MARINE BIOLOGY OF THE GOVERNMENT JETTIES IN THE GULF OF MEXICO BORDERING THE TEXAS COAST TJIIs IS All ORI .If Jf.U GINAL Jl!NtJSClUPT Ill NOT BE COPIED WITHOUT. . .!UTHOB'S PERMISSION , Approved: I I Approved: MARINE BIOLOGY OF THE GOVERNMENT JETTIES IN THE GULF OF MEXICO BORDERING THE TEXAS COAST THESIS Presented to the Faculty of the Graduate School of The University of Texas in Partial Fulfill-m.ent of the Requirements For the Degree of MASTER OF ARTS By Horace Logan Whitten, B. A. (Gladewater, Texas} Austin, Texas August, 1940 TABLE OF CONTENTS CHAPTER PAGE I. IlJTRODUCTION 1 Purpose of Thesis • • • • • • • • • • • • • • 1 Previous Literature • • • • • • • • • • • • • 1 Acknowledgements • • • • • • • • • • • • • • • 2 II. GEOGRAPHY AND TOPOGRAPHY OF THE JETTIES 3 III. COLLECTION AND CLASSIFICATION OF SPECIMENS • • 8 THE SABINE VfEST JETTY 15 TY• • • • • • • • • • • • • V • THE GALVESTON JETTIES . . . . . . . . . . . . 26 VI. THE FREEPORT JETTIES • • • • • . . • • • • • • 50 VII. THE PORT ARANSAS JETTIES • 65 VIII. THE PORT ISABEL JETTIES 89 IX. CONCLUSIONS 97 BIBLIOGRAPHY • • . . . . . . . . . . . . 104 APPENDIX: CHECK LIST OF SPECIES • . . . . . . 108 VITA ••• • • • • • • • • • • • • • • • • • • 123 iv LIST OF ILLUSTRATIONS AHD MAPS FIGURE PAGE I. Sabine West Jetty, Station 30-00 ••• • • •• 13 II. Camp Trailer Used on Collecting Trip • • • 13 III. Map No. I, Showing Jetties at Sabine, Texas • 14 I:V,A. Galveston North Jetty, Station 30-00 •••• 24 IV,B. Galveston South Jetty, Station 160-00 ••• 24 v. Map No. II, Showing Jetties at Galveston, Tex. 25 VI,A. Freeport North-East Jetty, Station 26-00 •• 48 VI,B. Freeport South-West Jetty, Station 47-00 •• 48 VII. Map No.III, Showing Jetties at Freeport, Tex • 49 VIII,A. Aransas Pass North Jetty, Station 90-50 •• 63 VIII,B. Aransas Pass South Jetty, Station 20-00 •• 63 IX. Map No. J:v, Showing Jetties at Port Aransas, Texas • • • • • • • • • • • • • • • • • • • • 64 X,A. Port Isabel North Jetty, Station 30-00 ••• 87 X,B. Port Isabel South Jetty, Station 25-00 ••• 87 XI. Map No. V, Showing Jetties Near Port Isabel, Texas • • • • • • • • • • • • • • • • • • • • 88 THE LIBF~ARY THE UNIVERSITY OF TEXAS CHAPTER I INTRODUCTION This thesis should be considered as a preliminary survey of the biology ·of the govern...~ent jetties of Texas, which may help to create interest in the various types of ecological problems not yet investigated. Nothing has been written about the fauna of the jetties, and very little concerning the open beach itself. In the words of Dr. Shoemaker, of the United States National Museum, "As far as I am aware, almost no collecting has been done on the Texas coast, and we know almost nothing of its amphipod fauna."1 1Personal letter from Dr. Shoemaker, May 31, 1940. Probably the most recent check list of any part of the area is a bulletin of the Texas College of Arts and Industries, Kingsville, Texas, by J. c. Cross and Hal B. Parks, entitled "Niarine Fauna and Sea-Side Flora of the Nueces River Basin and the Adjacent Islands." This bulletin presents a good cross-section of the great number of forms present in a small, definite area, but it do es not deal with the animals quan­titatively. The only other publications directly centered around the Gulf coast are bulletins of the United States Bureau of Fisheries and the works of Evermann and Kendall. The Fish­ eries Bulletins are concerned only with shrimp, oysters and a few fishes, while Evermann and Kendall limit their discussion to fishes of the region, about one hundred of 2 which are salt water species. 2Game, Fish and Oyster Connnission, Bulletin 5, "Fishes of Texas," (Austin, Texas, 1932), 5. Various marine publications and keys were used in preliminary identification, but for final verification of many species, the writer is indebted to experts con­nected with the Smithsonian Institution. Their names and departments are listed in Chapter III, and the specimens classified by the Museum are indicated in the check list in the appendix. Maps and necessary information concerning the jetties have been received from the office of the United States Engineer, Galveston, Texas, and elsewhere. The writer wishes to express his thanks to these organizations, and to individuals who have helped in various ways, including the members of the thesis committee. CHAPTER II GEOGRAPHY AND TOPOGRAPHY OF THE JETTIES There are numerous geographical and topographical conditions peculiar to the Gulf coast of Texas. Probably the most noteworthy of these conditions is the chain of islands separated from the mainland by several bays. These islands are also separated from each other by eight passes, distributed throughout the four hundred miles of coast line. It may be mentioned in passing that the fluctuating salinity in the bays, notably in Laguna Madre, destroys thousands of pounds of fish and other marine 1 life at intervals. For this reason, the dredging of mew 1Annual Report of the Game, Fish and Oyster Comm­ission of Texas, (Austin, Texas, fiscal year 1937-38), 31. artificial passes is being considered at present. The United States Government has constructed five sets of rubble-stone jetties along the Texas coast within the past sixty years. These jetties serve as breakwaters, and are located at the passes referred to above, except the Freeport jetties, which extend from the mainland. The other jetties are located at Sabine, Galveston, Aransas Pass and Port Isabel. Although there are several municipally-cwvned jetties, or breakwaters such as the one at Corpus Christi, this thesis deals only with the government jetties, all of which are located in the Gulf proper. These five sets of jetties are maintained by the government to protect the shipping channels along the coast. Another ecological problem which at once presents itself is that of comparing the life forms of the jetties within the bays with those on the Gulf. This problem has not yet been undertaken by the writer because there are many factors such as salinity, pollution, and turbidity, which would need much more consideration than that given them in this thesis. It is hoped, however, that this com­parison will be made some time in the near future. Due to wave action, settlement and scouring along the "toes of slope", or bases of the jetty rocks, repair work has been carried on almost continually during the past sixty years. These changes, however, affect the fauna of the jetties only slightly, since the stones are never removed from their original positions. At the present writing, the north jetty at Port Isabel and tre south jetty at Sabine are undergoing repairs at the extreme gulfward ends. During recent years concrete caps have been placed on portions of the jetties at Sabine, Galveston, Freeport, and Aransas Pass. Also, a section of the south jetty at Galveston has been covered with an asphaltic-concrete material as an experiment. A better understanding of the physical nature of the jetties may be had by referring to the maps preceding each chapter. The five maps included are reproduced by permission of the War Department of the United States, and are known 5 as project maps. From these maps it is possible to secure such information as the following; range of tide, mean low tide, streams affecting salinity, relation of jetties to surrounding land, length and structure of jetties, and location of points, or stations. Most of the information pertinent to this investigation will be included in the discussion of each station. The stations are not only helpful in referring to the maps, but while in the field they are invaluable in de­termining one's exact position. In most cases, the station numbers are painted on the jetty rocks or concrete caps, and are easily seen. For this reason, the station m.mb ers used in the maps will be used in this thesis, as well as other map information that is found to be practicable. The writer has attempted to divide all the jetties into ecologically similar areas, or sections. Each of these sections is located between two of the so-called stations, and each section usually has topographical differences de­scribed in the discussion. The stations are simply points on the jetty marked off in tens and hundreds of feet, separated by plus signs. For example, "Station 11+50" indicates a point on the jetty located at a distance eleven~hundred-fifty feet from the shoreward end. "Stations 11+50 to 11+60" simply means a section of the jetty ten feet long, located eleven-hundred-fifty feet from shore. The jetties themselves present an ecological condition even more outstanding than any of the other factors involved. There is an absence of rocky shores in Texas, and the jetties form an artificial habitat for many species of animals and plants which might even be absent from our outer coast if the typical sandy beaches alone were present. On the other hand, from an economic standpoint, the jetties might interfere with the shrimp and fish industries to some extent. It is probPble that some shrimp and fish spawn in the Gulf near the p2sses, and the larvae make their way into the bays to feed and to seek protection from wave action and their natural enemies in the animal kingdom. If so, it is the opinion of the writer that this migration is often checked or prevented entirely by the jetties extend­ing into the Gulf, sometimes a distance of five miles. If these animals spawn in the bays, the adults have the sa..~e problem in gaining entrance to these bays. In many cases, however, the animals have no difficulty in finding crevices between the rocks, at least during high tide. This is evident after each receding tide, as one may find an abund­ance of larval forms left in small pools beyond the seem­ingly impenetrable jetty walls. Still another condition resulting from the building of the jetties is evidenced in the fauna of the passes. Formerly these passes were shallow inlets to the bays, acted upon by the rough surf. Now, the passes between jetties are dredged to an average depth of thirty-four feet, for use as shipping channels. The species of animals in­ habiting these channels are necessarily different from those found in shallow water washed by waves of the open Gulf. Reference to this fact will necessarily be made elsewhere. CHAPTER III COLLECTION AND CLASSIFICATION OF SPECilvlENS In preparation for the writing of this thesis, specimens were collected during the months of June and July of the years 1938, 1939 and 1940. The collecting of the first two SULTu'TI.ers was done primarily to secure type specimens for taxonomic work. The field work of the present season was devoted mainly to observation of physical conditions and distributions, as well as col­lecting. In all cases an attempt has been made to treat the material from an ecological standpoint, and to con­sider the taxonomic work of secondary importance. Although the physical and chemical factors~fecting a region are of great ecolop.ical importance, they are only of relative significance in this investigation, because no comparisons have been made over a period of years. Unless otherwise specified, all observations were made on average days in June, 1940, as far as weather, salinity and other factors were concerned. The water temperature at the surface ranged between twenty-nine and thirty-one degrees centigrade, during daylight hours. The turbidity of the water at the time of collecting was about the same at all jetties except at Port Isabel, where turbidity was greater. "The average salinity of Aransas Bay, (and similar bays), throughout the year is 16 0/00, which means that one thousand parts of water contain 16 parts of salt. The salinity increases during July because of increased 1 evaporation.n Chemical analyses of the wat er were not 1 Annual Report of the Game, Fish and Oyster Com­mission of Texas, (Austin, Texas, fiscal year 1937-38), 34. made by the writer. All collecting was done during day­light hours unless otherwise stated. Results of storms and unusual disturbances were taken into account. Collections and observations of specimens were limited to the area on top of, and around, the jetties; and beneath the water to a point about five feet below mean low t:id e level. Dredging of the lower strata obviously would reveal forms not mentioned in this work, but the writer was unable . to secure dredging equipment suitable for use in such rocky areas. Various kinds of dip-nets were used, as well as round shrimp nets, regular shrimp nets and minnow seines. Some of the seining was done with the assistance of bait fishermen in motor boats. This was necessary in collecting fish near the ends of the jetties where the water was rough. The specimens collected during the two previous years were preserved in formalin, and arranged according to the station numbers at which they were collected. Then as already indicated, a preliminary classification was madie by the writer, who used keys and check lists such as those listed in the bibliography. During the past year, type specimens of the major part of the invertebrates collected were sent to the Smithsonian Institution for verification. Below are names of the various experts connected with the various departments of the museum, who personally classified the groups follOW'ing their names: Dr. Paul Bartsch, Curator of Mollusks, mollusks. Mr. Milton J. Lindner, of the United States Bureai of Fisheries, shrimp. Dr. c. Mc Lean Fraser, hydroids. Dr. Waldo L. Schmitt, decapods. Dr. Clarence R. Shoemaker, Assistant Curator, Division of Marine Invertebrates, jellyfish and amphipods. Mr. J. o. Maloney, isopods. Dr. Olga Hartman, annelids. Dr. R. s. Bassler, Head Curator of Geology, bryozoa. Mr. E. c. Leonard, plants. :Mr. Austin H. Clark, Curator of Echinoderms, echinoderms. Mr. I. E. Cornwall, barnacles. Mr. A. Wetmore, Assistant Secretary of the Smithoonian Institution, supervisor. The specimens identified by the Museum staff are in­ dicated in the check list in the appendix, and a number of specimens sent to the Smithsonian: Institution have not been classified to date. A complete classified set of specimens has been retained and may be used as proof in any question of identification. The writer will be responsible for all 2 other errors in taxonomy. 2several coelenterates sent to the Museum have not been sent out for verification because the specialist in that field is now in the war zone of Europe. In the study of the plants found, the only forms considered were the Sargassum plants left stranded among the rocks, and the dominant species of algae actually grow­ing. No attempt was made to classify the secondary algae, as only small patches were found, and a thorough search was not made for these less connnon forms. A master's thesis was written at the University of Texas in 1938, by Beulah s. Smit.h, entitled "A Study of the Algae of the G.ulf Coast of Texas•" Her thesis is a survey of the algae o:f the entire region, and may be consulted on questions of both classification and distribution. The only fish considered to be true jetty forms are those which were found inhabiting regions between the rocks in comparatively large numbers, because few fish actually inhabit the jetties. This is due to the fact that most of these fish prefer quieter waters, or water deeper than that investigated. It is true that many of the hundred or more salt water species found on the coast may be caught near the jetties, but they are usually only swimming around the rocks, or seeking shelter in lower strata. Hence, such fish cannot be said to inhabit the jetties, since their life histories substantiate the fact. The writer has seinai many areas bordering the jetties with a shrimp net, and ·has caught various species ordinarily found only in open water, (limnetic connnunities). These have been om.itted as ir­ relevant in cases where they are known to be strictly deep-water forms. The jetsam deposited on the jetties, consisting of the gulfweed, Sargassum, logs wedged between the rocks, and other debris has been included. Thus the reader may expect to find forms listed which are not permanent in­habitants, and others which are only seasonal. These in­clude certain hydroids, goose barnacles, pipefish, and many more species discussed later. Other specimens ordinarily associated with sandy beaches are necessarily listed, because the animal and plant communities formed by some jetties include parts of the sandy areas. This is clearly shown in the photo­graph of the Port Isabel south jetty, figure X.B. Some of these seashore forms were the sand dollar, starfish, certain bivalved mollusks, the "sea pen'', some algae, and others. Insects and birds of this region are also listed if actually observed in comparatively large numbers on the jetties, or if found to be regular influents. The main interest, however, is centered on marine invertebrates. WEST JETTY, SABINE Station 30+00 FIGURE II Camp Trailer Used on Collecting Trip 480625 14 CORPS OF ENGINEERS, U S ARMY WAR DEPARTMENT CHAPTER IV THE SABINE VlEST JETTY To the casual observer, the west jetty at Sabine, with its eroded concrete surface, would present very little of interest to the ecologist, as shown in figure I. On closer examination, however, even the section illustrated in the photograph is teeming with life. On this jetty alone, forty-odd species of marine fauna have been identified. This jetty extends southward into the Gulf a distance of 21,860 feet. Between it and the east jetty in Louis­iana, is located Sabine Pass. Water in this pass comes from Sabine Lake, a large body of water fed by the Sabine and Neches Rivers. The Sabine jetties are almost one-half mile apart, and the average depth of the channel between is thirty-six feet. The granite rocks of the jetties, which remain above low tide level, are cover rocks, ranging in weight from eight to twelve tons. The width of the jetties above sea level is only four to eight feet, while at the base, er toes of the jetties, the width is forty to eighty feet. (See cross-section of jetty in figure III). The range of tide along the Sabine west jetty is approximately one and one-half feet. Wave action varies at individual stations, as described in the discussion. STATIONS 0+?0 to 80+70 The littoral region to the west of the first station is a typical mud flat during low tide. During high tides lo and storms, water seeps under the concrete cap and ara.ind the west side of the jetty, converting the mud flat into a salt marsh. The fiddler crab-rush grass community, composed of the crabs Uca pugilator and Uca minax; and the seashore rush grass, Sporobolus virginicus, was found here. The jetty itself was not overlooked by these crabs, which could be seen scurrying from every crevice on the west wall to the more permanent shelter of holes in the mud among the rush grass. It may be mentioned that this was the only dominant strand -plant found to be associated with either of the jetties. The situation at this station affords a good opportunity for inter-tidal plant growth, but only the single species of plant has persisted. High on the leaf blades of approximately every twentieth plant could be found active specimens of the salt-marsh periwinkle, Littorina irrorata. On the west side of the jetty, there was a scattering of this large littorine in company with the more abundant but smaller Littorina ziczac Gmelin, on the jetty wall. The small littorines were numerous on both · sides of the concrete cap, numbering as high as one-hundred-fifty per square meter. Also numerous on both sides, in all strata of vertical distribution, was the swin:L~ing crab, Callinectes sapidus. At the writer's last visit to this jetty, young crabs measuring only two millimeters in length were so numerous on the west side of the jetty that a quart jar could easily be filled with them after two or three drags with a small dip-net. Young shrimp, (mysids), of the species Penaeus brasiliensis and Xiphopenaeus kroyeri were found together in the same area, though not plentiful. On the top and sides of the jetty near the shore regions, the large isopods, Ligyda exotica (Roux), were found to be abundant, their complete domination of the concrete cap being disturbed only by fishermen. At times, however, the ro?ber flies, Erax rufibarbus; and horse flies, Tabanus, sp., almost outnumbered the isopods. At least, in any ecological work of this station, these insects should not be overlooked. This also applies to at least two species of birds which frequented the jetty wall at this point. The great blue heron, Ardea herodias; and the willet, Catoptrophorus semipalmatus; though not nmnerous, were always present, searching for food on the shore side, especially for mullet, Mugil cephalus (Linnaeus). These fish were taken in schools near this and other jetties, but they are not strictly jetty fish. Common minnows, Gambusia, sp., were always present in the brackish water of this region. A salt-water strider similar to Hydrometra was also present. STATIONS 80+?0 to 131+?2 This area was somewhat like the preceding except for the absence of a muddy shore on the south side. The benthic area, a few feet below the surface at low tide, was easily explored, however, and it appeared that the dominant species of the past had been the oyster, Ostrea virginica Gmelin. The empty shells of this oyster were abundant, but the mud and silt had covered and smothered them some time ago. Other mollusk shells found bordering the jetties were as follows: the jackknife clam, Tagelus gibbus Spengler; the red oyster, Spondylus americanus Lamarck; worn specimens of the bivalves Noetia ponderosa Say and Donax tumida; a few jingle shells, Anomia glabra; and the bay form of the moon snail, Natica duplicata. On the walls of the jetty, washed by strong waves from both sides, the rock barnacles Balanus improvisus Darwin and Balanus eburneus Gould were making a desperate stand. Half of those examined proved to be empty shells, but in all, there were about fifty barnacles per square yard, most of which were above low tide level. Among these were only a few littorines, Littorina ziczac, and some of the small species Nerita versicolor Gmelin. STATIONS 131+72 to 157t80 This area was undergoing repairs to the concrete cap of the jetty, and was not examined by the writer in 1940. It has only one dominant community above the benthic area, however, and that is the Balanus-Littorina connnunity. These two forms become more and more numerous toward the end of the concrete cap, at station 157-80. STATIONS .157+80 to 218+60, (End of Jetty) Two species of gulfweed, Sargassum natans (L.) Meyen, and Sargassum fluitans Borg., are usually present as jetsam on rocks of the jetties after the tide recedes. At this section of the Sabine jetty, they are found in summer in large numbers. These Sargassum plants, when examined this season, revealed many interesting speci~ns. Two species of annelid worms, Nereis pelagica and Lumbrinereis tenuis, were the dominant forms in some of the Sargassum. Gelatinous masses, in which young worms were present, almost covered entire plants. Other gulf­weeds were decorated with the beautiful hydroid Aglaophenia minuta Fewkes, interspersed with smaller growths of Clythia cylindrica Agassiz, and Sertularia versluysi Nutting. A few were encrusted with the bryozoan Acanthodesia savartii Savigny-Audouin. Two types of nudibranch mollusks averaging one-half inch in length were rather numerous, as well as Sagartia luciae Verrill, a small gray sea anemone which was abund­ ant. One of the nudibranchs was found t _o be Aeolis, sp:., and the other has not been identified. Algae are not connnon on this jetty, although a few species may be found, including Enteromorpha lingulata J. Ag., and Cladophora fascicularis (Mertens) Kutz, as primary inhabitants. From an ecological viewpoint, the rocks of the area, as well as all other jetty rocks, may be considered as sub-climax connnunities, since they are relatively stable. The so-called cover rocks weigh from six to ten tons ea ch ' and have an average length and width of six feet. In a climax community, an area of approximately two square yards is known as a lociation, and in many cases one of these rocks may be referred to as such. In other cases, the rock surface is small enough to include only one-half square yard, and such a community may be called a clan. At the end stations of this jetty, lociations of the limpet, Siphonaria lineolata Orbigny, the barnacle Bala.nus improvisus Darwin, and the snail, Thais floridana Conrad, were found on each rock, with some algae present. There were often ten or more snails per lociation. The limret was not abundant her~ and was absent at most other stations on the Sabine jetty. In the water among the jetty rocks, about ten mantis shrimp, Squilla empusa, were caught along with other nore common shrimp • . Mullet were present in large numbers, but no typical jetty fish were collected. Five rock crabs, Menippe mercenaria, were observed in the area, wedged tightly between rocks just above water level. This number indicates that an abundance of this species was present. No other crabs and no isopods were collected at this end of the jetty above the benthic area, which is deep on both sides of the jetty. The extreme end of this jetty is characterized by rough water at times, since it extends so far into the Gulf. In the past, no dredging of a scientific nature has been done near this jetty. For this reason, it would be desir­ able to dredge the lower strata and make comparisons. No collecting was done on the east jetty,. since this jetty is in Louisiana. A comparison would probably reveal habitats and specimens similar to those of the west jetty at corresponding stations, except for the absence of a salt marsh and mud area. SUMMARY Note: Figures to the right of the specific names refer to the average number of individuals per square meter, unless otherwise specified within the parentheses. SABINE WEST JETTY STATIONS 0+?0 to 80470, West Side, (Mud flat during low tide and salt marsh during high tide; Uca-Sporobolus c onnnunity) • Number of Individuals Species Common Name Per Square Meter Sporobolus virginicus. Rush Grass (dense growth) Uca pugilator. Fiddler Crab 20 Uca minax. Fiddler Crab 15 Littorina irrorata. Littorine 1 Littorina ziczac Gmelin. Littorine 20 Callinectes sapidus. Crabs 2 Penaeus brasiliensis. Shrimp 1 Xiphopenaeus kroyeri. Sea-Bob 1 Ligyda exotica Roux. Isopod 30 Erax rufibarbus. Robber Flies O' to 20 Tabanus, sp. Horse Flies 1 Ardea herodias. Great Blue Heron (2 birds per thaisand ft.) Catoptrophorus semipalmatus. Willet (1 per thousand ft. ) Mugil cephalus Linnaeus. Mullet 1 to 20 Gambusia, sp. Minnow 1 Hydrometra?, sp. Salt-v'later Striders ( groups of 15 ) Mneiopsis, sp. Comb Jelly (few collected, 1938) STATIONS 80+70 to 131+72, East Side, (Water three to six feet deep at toes of jetty rocks). Empty Mollusk Shells found at Toes of Jetty: Spondylus americanus Lamarck. Red Oyster Ostrea virginica Gmelin. Connnon Oyster (abunlant) Tagelus gibbus Spengler. Jackknife Clam Noetia ponderosa Say. Bivalve Donax tumida. Bean Clam Anomia glabra. Jingle Shell Natica duplicata. Moon Snail Jetty Forms found on Rocks of Jetty: Balanus improvisus Darwin. Rock Barnacle 30 Balanus eburneus Gould. Barnacle 20 Littorina ziczac Gmelin. Littorine 6 Nerita versicolor Gmelin. Snail 1 STATIONS 15?+80 to 218+60, Both Sides, (Rock area extending into the deep water of the Gulf; water eight to twenty feet deep at toes of jetty). Specimens on Jetsam: Nereis pelagica. Nereis Worm (abundant on Sargassum) Lumbrinereis tenuis. Nereis Worm (30 collected) Aglaophenia minuta Fewkes. Hydroid (the dominant specie:> found in the Sargassum) Clythia cylindrica Agassiz. Hydroid (scarce) Sertularia versluysi Nutting. Hydroid (scarce) Acanthodesia savartii Savigny-Audouin. Bryozoan ( found on 3 plants) Aeolis, sp. Nudibranch Mollusk (2 per plant) Sagartia luciae Verrill. Sea Anemone. (1 per Sar&:lssum plant examined) Sargassum natans (L.) Meyen. Gulfweed Sargassum fluitans Borg. Gulfweed Jetty Forms: Enteromorpha lingulata J. Ag. Alga Cladophora fascicularis (Mertens) Kutz. Siphonaria lineolata Orbigny. Limpet Balanus improvisus Darwin. Barnacle Thais floridana Conrad. Snail Sguilla empusa. Mantis Shrimp Mugil cephalus. Mullet (Fish) Menippe mercenaria. Rock Crab (abundant) (abundant) (scarce) Alga (abundant) 10 30 10 (10 collected) 1 to 10 1 FIGURE IV ,A NORTH JETTY, GALVESTON Station 30+00. Concrete Cap Extending fron Bolivar Peninsul~ is Shovm in Background :FIGURE "IV , B SOUTH JETTY, GALVESTON Stetion 160+00, Showing Asphaltic Concrete Cap VAR DEPARTMENT CORPS OF ENGINEERS U. S. ARMY ~ a Ci ~ ~ (; I ~ 0 0 .. ~ Ili~!-i on ~­ ,,. ,, ! Typ1c.al Cro~s Se.c.tionof So .Jett.y Sta 191•50 tc S'..a :30->9 shoo.-n~ ~'Jl>haltic. Cuncrete C.ap SCALE I 80,00C 0 I -.plUll Cross Sec.t;on of Worth le•., :ta O•!'>B:i ~ Sta 2t1Qo sho"fie waterway listed below, Jetties at mouth of the river; a Diverc;ion Channel and Dom and necessary auxillary works including construction of Lock in Dam. NEW WORK MAINTENANCE CONT FUNDS TOTAL COSTS: To June 30 1939 was Pr~. 1us pr~iect' Ex1sf"1q project $ 147,098.43 $1, 217, 636.63 none $ 1,953,119.42 $1,086,025.00 $ 758,302 79 $1,233,123. 43 $ 3,929,058 84 1~ . 01 $1, 364,735 06 $ 1,953,11942 $I ,8 44,327.79 $5,1 62 ,1 82 .27 PROGRESS: The project is85% completed HEAD OF NAVIGATION : Diversion Dom, 2 miles above Freeport. COMMERCE : For calendar year 1938 was 222,108 tons valued at $ 3,~36,911.00 RANGE OF TIDE : 1.5 ft. FIGURE VII CHAPTER VI THE FREEPORT JETTIES The jetties at Freeport are comparatively short. The south jetty is the longer of the two, and lacks three­hundred-eighty feet being a mile long. These jetties are also closer together than any others, and the water between them is ordinarily smoother. At present, they are not fre­quented by fishermen, especially the south jetty, because of the laying of pipe lines across the road to this jetty. Although the coast line at this point extends somewhat into the Gulf, the jetties themselves are not often repaired, because they are so short. In this discussion, each jetty will be divided into two sections, the first section in each case being the part covered by a concrete cap. NORTH-EAST JETTY STATIONS 0~00 to 25+00, (End of Concrete) This section extends only a little beyond the shore line, and the area to the south is sandy and slopes down­ward to the beach at station 20+00. Thus, only the rocks on the south side support any marine life. The water in this channel averages twenty-five feet in depth. Since the jetties are not far apart, the water near them is re­latively deep, often reaching a depth of ten feet within six feet of the toes of the jetty rocks on the channel side. This situation was responsible for the fact that some deep­ water species were caught in this region. The photograph preceding this chapter, figure VI,A, was included to show the abundance of algal vegetation found on the rocks at all stations. There was a denser growth on the channel side due to calmer water. Of the numerous. species of algae present, the following formed the principal cormn.unities: Ulva lactuca L., Cladophora fascicularis, Enteromorpha lingulata J. Ag., Padina pavoni J. Ag., and several other species of these same genera. None grew in water deeper than one meter below low tide level. In the algae-covered area were found Caprella-Oarino­gammarus lociations, on almost every rock. Only one species of Amphipod was identified by experts, although there was a green Caprella present which may have been a variant. Those identified were the "skeleton shrimp", Caprella acuti­frons Latr.; and the "scud", Carinogammarus mucronatus. Males are much larger than females, and both hold to algae by prehensile hind legs. In moving about, they often p.ro­ceed in measuring-worm fashion. Those collected were obtain­ed by first removing the Cladophora from the rocks. These animals are among the most grotesque and unusual of thojse found on our Gulf coast. Secondary dominants were the musse:ls, Brachidontes {Ischadium) recurvus Raf.; the periwinkles, Littorina ziczac Gmelin; star-shaped barnacles, Balanus glandula; limpets, 52 Siphonaria lineolata Orbigny; snails, Thais floridana Conrad; and hermit crabs, Pagurus pollicaris. There was a much larger number of species living in the same habitat at this station than at any other single station on any jetty, probably because of the abundance of algae. Barnacles of this region were found at lower strata of the rocks than at other jetties where waves were stronger. That is to say, they were growing in the inter-tidal area only. The mussels had grown to only two centimeters in length at this place, and there were few present; while at other stations on this and other jetties they were the dominant species, a.nd were olde""'r and larger individuals. This indicated that there was a succession in operation at the first station. The algae seemed to have little in­fluenoe, however, as they were plentiful at all stations, even growing from the shells of all mollusks collected. Three species of annelid worms were found among the algae in small numbers. They have been identified as Lepidonotus polynoe, Nereis virens and Lumbrinereis tenuis. These are not always found in algae, although the writer found hundreds of the Lumbrinereis worms in floating Sar 1 -gassum. One annelid, Serpula vermicularis, is a typical 1 rt is regrettable that all the Hereis worms collected have not been identified by Professor Moore of the Uni­versity of Pennsylvania, who is an authority on these worms. beach worm which makes tubes on mollusk shells usually found 53 on beaches. This worm makes small, coiled, calcareous tubes which were usually empty when found. The worm, when observed, has feather-like gills which extend from the opening of its tube. Grinding action of the sand, caused by the waves, usually destroys these worms on open beaches. Those found were on the beach at station 20+00. Other beach forms found on the north side of the jetty rocks were unattached Thais eggs; tests of the sand dollar, or key-hole dollar, Encope michelini (L• .Agassiz); "sea bobs," Xylopenaeus kroyeri; Sargassum; sea beans; and empty rrnllusk shells. At the toes of the jetty rocks were found three species of burrowing sand crabs. After each wave receded, small jets of water, or depressions in the moist sand, revea'led the presence of one of these crabs or the bean clam, Donax variabilis Say. The most common crab was Emerita benedicti Schmitt, with a large number of Hippa talpoida interspersed among them. 1'he Emerita is oval and cylindrical, so that it may quickly burrow into the sand after each wave. The best method of collecting these crabs is to drag a net through the waves, walking parallel to the shore. In this manner, these crabs and the Donax clams may be taken before they burrow in. Both are used as food by curlews and willets, (shorebirds); and by certain fish which are said to swim into the breakers near shore in search of these crabs. The other crab, Lepidopa myops Stimpson, is called a spiny sand crab, and is shaped more like the well-knovn crab. 54 It has extremely long, feather-like antennules which are left extended, and parallel to each other while the animal is in the sand. These antennules thus form a breathing tube which may be seen above the sand. STATIONS 25+00 to 45+00, {End of ~etty) This last section was very similar to the first, ex­cept that both sides of the jetty were washed by waves which churned back and forth through large openings be­tween rocks. In these spaces young fish of three species were caught: tarpon, Tarpon atlanticus (Cuvier and Val­enciennes); mackerel, Scomberomorus maculatus (Mitchill); and redfish, Sciaenops ocellatus {Linnaeus). These fish were never observed over one meter below the water surface, although the area was sampled to the two-meter level. The water on both sides of the jetty at this section was approximately thirty feet deep. The first "jetty fish" discovered by the writer was found on the rocks of this area. This was the rock skipper, Rupiscartes atlanticus (Cuvier and Valenciennes). Large numbers were caught in a dip-net, without any special effort being made on the part of the collector to find them. These fish are tropical forms ranging from eight to sixteen centimeters in length. Their ventral and pectoral fins are equipped for holding them to the seaweed and rocks, where they are always found, rather than in open water.. A beautiful purple coelenterate, the sea pansy, Renilla amethystina Verrill, was found among the rocks at Freeport. The heart-shaped body, or rachis, of the colony contains about four hundred individuals. At night, if prodded, the coelenterate shows 1 uminescence. ·when caught, the individuals draw themselves into the rachis in the same manner as the tentacles of sea anemones are retracted. The only other coelenterate found was the sea anemone, Tealia crassicornis, which occurred in clans by itself on inner rocks of this area. Outside rocks had communities similar to those of the first station, except that the star-shaped barnacles became the dominant species. Insects were scarce on the Freeport jetties, and no isopods were found. The algal growth continued abundant to the end of the jetties. A few large moon snails, Polinices duplicata Say, were found here, as were their shells, occupied by hermit crabs. When approached, the crabs dropped off into the water, leaving only the snails attached. In this way it was easy to determine ·which were snails and which were crabs. Those Polinices snails found here were in Balanus­Thais clans. It was interesting to observe that all com­munities were thickly populated. In some instances, clans of large Brachidontes mussels were found here as dominants on certain rocks, as already mentioned. A few large purple sea urchins, Arbacia punctulata (Lamarck), were found in deep crevices, one meter deep, between the rocks of station 40+00. Sea urchins were never numerous at any jetty. SOUTH-WEST JETTY STATIONS O+OO to 46tOO, (End of Concrete) The sand in the area to the south of this jetty section was inhabited by the sand crab Ocypode albicans Bose., but these crabs were seldom on the jetty, and then only at night. Callinectes crabs were numerous en the channel side. The beach area at station 40+00 was similar to the corresponding area on the north jetty. The sand, which was even with the concrete top of the jetty at station o+oo gradually sloped to the water's edge at station 40+00. From this point to station 46f00, the water in­ creased in depth to thirteen feet on the north side and twenty feet on the south side. Empty mollusk shells collected at the toes of the rocks were as follows: the jack-knife clam, Solen vagina; small angelwings, Petricola pholidiformis; many large angelwings, Barnea costata Linne; venus shells, Venus mercenaria Linn~, and the larger venus, Venus campechiensis Gmelin; the heart shell, Trachycardium (Dinocardium) robustum Solander; the discus shells, Dosinia discus Linne and Dosinia ponderosa; and the turret shell, Turritella varigata, sometimes occupied by small hermit crabs. .Amphipods were abundant on rocks of this section as on the north-east jetty, but it was observed that they preferred the north (channel) side of the jetty. The "sea liver" Renilla was caught here, and several small hermit crabs on the jetty were found to be occupying mitre shells, Mitra cinctella; and turret shells, Turritella varigata. A purple crab, Randallia ornata, was caught in com­paratively large numbers in the deep water, (over two meters deep). This is a spider crab of the lower strata, col­lected exclusively at this station. It differs from :roost spider crabs in being purple. Although this species is not rare, the writer has not seen specimens from any other locality on the coast. Besides the young fish already mentioned, the mull.et, Mugil cephalus (Linnaeus), was found in schools near the surface. STATIONS 46i00 to 49+00. (End of Jetty) This last station was the shortest thus far cons:idered. It was characterized by lociations of Balanus barnacle=s and Thais snails, with secondary dominants Littorina irrorata, and at times, Brachidontes (Ischadium) recurvus Raf. The limpet, Siphonaria lineolata Orbigny, was also abundant, as were the algae already discussed. The rock skipper, Rupiscartes atlanticus, was most plentiful here, and could at least be classed as an impor­ tant influent. Other full-grown fish collected were the pompano, Trachinotus carolinus (Linnaeus); the swell-fish, Spheroides spengleri (Bloch); and a beautiful species known as the bank butterfly fish, Chaetodon ocellatus (Bloch), found only in the Gulf of Mexico, and collected by the writer only at this station. Hermit crabs and some swimming crabs were present, as were three clans of large sea anemones, Tealia craffii­cornis. On a few rocks could still be found both species of Caprella. Ther~ as at other stations, were several laughing gulls, Larus atricilla. The scarcity of bays and marshes accounted for the absence of shorebirds. Insects, (and dead fish), were absent in this region, as far as the fauna of the jetties was concerned. SUMMARY Note; In the summaries, every species found at a given station is listed. Some forms may be accidental or rare species. The word "abundant" following species of algae indicates that these plants completely covered the inter-tidal rock surfaces of the area. FREEPORT NORTH-EAST J"ETTY STATIONS OTOO to 25+00, South Side, (Algae-covered rocks, forming Caprella-Carinogammarus lociations). Species Common Name Number per Square Meter Enteromor;eha lin~ulata J. Ag. Alga (abundant) Padina pavoni J. Ag. Alga (abundant) Cladophora fascicularis. Alga (abundant) Ulva lactuca L. Sea Lettuce: Alga (abundant) Caprella acutifrons Latr. Skeleton Shrimp 40 Caprella, sp. Aunt Fanny; Skeleton Shrimp 10 carinogannnarus mucronatus. Scud 30 Brachidontes (Iscadium) recurvus Raf. Mussel O to 20 Littorina ziczac Gmelin. Littorine 20 Balanus glandula. Barnacle 10 Siphonaria lineolata Orbigny. Limpet 10 Thais f loridana Conrad. Snail 7 Pagurus pollicaris. Hermit Crab O to 10 Lepidonotus polynoe. Annelids (5 collected) Nereis virens. Nereis Worm 1 Lum.brinereis tenuis. Nereis Worm 10 STATIONS 20t00 to 2ltOO, North Side, (Beach area). Serpula vermicularis. Worm tubes (on 10 shells) Eggs of Thais Snail (1 string) Encope michelini (L. Agassiz). Sand Dollar 3 (tests) Sargassum natans (L.) Meyen. Gulfweed 2 Sargassum fluitans Borg. Gulfweed 1 Entata gigas. Large "Sea Beans" 1 Mucuna sloanei. Small "Sea Beans" 1 Donax variabilis. Bean Clam 20 Emerita benedicti Schmitt. Sand Crab 6 Hippa talpoida. Sand Crab 2 Lepidopa myops Stimpson. Spiny Sand Crab 1 Empty Shells: Petricola pholidiformis. Angelwing 2 Solen vagina. Jack-Knife Clam 1 60 Barnea oostata Linn~. Large Angelwing 2 Venus meroenaria Linne. Venus Shell 3 Venus oampechiensis Gmelin. Venus 1 Traohyoardium robustum. Heart Shell 2 Dosinia discus Linne. Discus Shell 4 Dosinia ponderosa. Heavy Dosinia 1 Turritella varigata. Turret Shell 3 STATIONS 25t00 to 45fOO, Both Sides, (RockGulf; water thirty feet deep in some areas the toes of the jetty rocks themselves}. area in opEn not far from Tarpon atlanticus (Cuvier and Valenciennes). 5 Tarpon Scomberomorus maculatus (Mitchill).(school of 20) Mackerel Soiaenops ocellatus (Linnaeus). Redfish (schools of 10) Rupisoartes atlanticus (Cuvier and Valenciennes). Rock Skipper 1 Renilla amethystina Verrill. Sea Pansy 1 Tealia crassicornis. Sea Anemone (clans of 6 to 10} Polinices duplicata Say. Moon Snail 2 Arbacia punctulata {Lamarck). Sea Urchin 1 carinogannnarus mucronatus. Scud 10 Brachidontes recurvus Raf. Mussel O to 20 Littorina ziczac Gmelin. Littorine 15 Balanus glandula. Barnacle 30 Siphonaria lineolata Orbigny. Snail Limpet 5 Thais floridana Conrad. Thais Snail 5 FREEPORT SOUTH-WEST JETTY STATIONS o+oo to 46+00, at edge of beach). South Side, (Sand area, ending Ocypode albicans Bose. Sand Crab 1 Callinectes sapidus. Swimming Crab 1 Emerita benedicti Schmitt. Burrowing Crab 6 Empty Shells, etc.: Solen vagina. Jack-Knife Clam 3 Venus mercenaria LinnEf. Venus Shell 1 Dosinia discus Linne. Discus Shell 5 Dosinia ponderosa. Dosinia Shell 2 Astrangia, sp. Coral, small pieces 1 Sargassum, sps. Gulfweed, washed ashore 4 STATIONS O+OO to 46+00, North Side, (Algae-Caprella­Carinogannnarus lociations). Mugil cephalus Linnaeus. Mullet (schools of 40} Randallia ornata. Purple Crab 2 Tarpon atlanticus (Cuvier and Valenciennes).10 Tarpon Sciaenops ocellatus (Linnaeus). Redfish 10 Callinectes sapidus. Swimming Crabs 1 Penaeus brasiliensis. Shrimp 3 Caprella, all species. Skeleton Shrimp 30 Carinogannnarus mucronatus. Scud 25 Brachidontes recurvus Raf. Mussel 0 to 20 Littorina ziczac Gmelin. Littorine 25 Balanus glandula. Barnacle 20 Lum.brinerais tenuis. Nereis Worm 10 62 Thais floridana Conrad. Snail 30 Pagurus pollicaris. Hermit Crab 5 Various species of Algae (abundant) STATIONS 46f00 to 49+00, Both Sides, (Rock area in openGulf; water thirteen to thirty feet deep). Thais floridana Conrad. Snail 30 Balanus glandula. Barnacle 30 Littorina irrorata. Littorine 3 Littorina ziczac Gmelin. Littorine 20 Brachidontes recurvus Raf. Mussel 10 Siphonaria lineolata Orbigny. Limpet 20 Rupiscartes atlanticus. Rock Skipper 3 Trachinotus carolinus (Linnaeus). Pompano 1 Spheroides spengleri (Bloch). Swell-Fish 2 Chaetodon ocellatus (Bloch). Butterfly Fish (2 collected) Pagurus, sps. Hermit Crab 3 Callinectes sapidus. Swim.ming Crab 2 Tealia crassicornis. Sea Anemone 2 Caprella acutifrons Latr. Skeleton Shrimp 3 Larus atricilla. Laughing Gull 2 Various species of Algae (abundant) Amphitoe, sp. Amphipod 1 J"assa marmora.ta Holmes. A..mphipod (10 collected) FIGURE VIII,A NORTH JETTY, ARANSAS PASS Station 90+50, on st. Joseph Island FIGURE VIII ,B SOUTH JETTY, ARANSAS PASS Station 20+00, on Mustang Island 64 CORPS OF ENGINEERS,U.S.ARMY PRQ6R[55: ~70% compkk ---~·-M.L.T~ 1iz;J~c4'~ COSTS: To June 3Q 1939 was T NEW WORK MAINTENANCE C.ONT FUNDS TOTAL YP. SEC : ~f-SP~RS Previous Project $I, 372,534.43 $ 62,451.86 .$ 411, 493.11 S t, 846, 479 4-0 SCALE· • SC £xi~tmgProject $4895.820~ J5,653,SBl.75 $1.52,555.09 $/J,7Jt,957.30 $G, 268 354 83 $ 5, 716 I 0 33 .6/ J564,048.20 1>12,548,486 70 , ;) '.. \'l • Sen:; ~p 0 DEPTH:Avo!lahle on Seti 30.1939 of M LT_ .. ' "" _T ~- Vlcmdy of Porl Aransas 35 /'I. .. ... 70 Ct5rpu5 Chri.sfi zq f'f ,, . ,­·\'' y( ,,, ' . . <:: .l.. R.MOt: or riot:.: 1.1 rl: 1 p·ci..L ss::. ot-• E r1£s sh:n.. ·,~ :JN: cA.P ~y;i C.~-;E:. '.; E "' Y So Je~t)'·Sto '.\ ·o~ ';..o S~ 31•SC s·.) :a• o ·...:i s:a 3;. 34 3 No. ' . y:;• 943 '.D • ot. •!>:l Sea~ • • S:>' l Seal~ l' · s~ · COMMt:..Rce.: FOr .'.935 . i .J ... /.~" 552, 912 kin,, valued of $ 18~ 880, G/9.JO MAP No.IV 1-£..NG TH : North, 1/,1,0 f'f. So" tp, , l,C!Oft. PORT ARANSAS-CORPUS CHRISTI WATERWAY TEX. CONDITIO~: SEPTEMBER 30,1939 SCALE : 1: 137,000 5000 1 0 ' ~-­ @ FIGURE IX CHAprfER VII THE PORT .ARANSAS JETTIES The jetties at Port Aransas protect Aransas Pass, which separates St. Joseph Island from Mustang Island. The pass connects the Gulf with Aransas Bay, viThich is an im­portant shrimp-fishing ground. The jetties, and the Aransas area in general, contain a greater variety of marine species, as a whole, than the other jetties discussed. This is partly due to the great nu1nber of inland bays of the area, shovm in figure IX. These bays are the habitats of VCJr ious animals, such as oysters, which are not found in the Gulf proper. Another factor is that Aransas Pass, being centrally located as it is, must necessarily be affected by many coastal storms and Gulf disturbances. Thus, many rare and "foreign'' specimens are sometimes collected in this region. NORTH JETTY STATIONS OtOO to 35+94, (Narrow Concrete Area) In order to reach the north jetty, it is necessary to take a boat to St. Joseph Island, which borders the first section of the jetty on the north. Marine specimens were collected, therefore, only on the south side. The fauna of this area vms limited to the barnacles Bala.nus impro visu,s Darwin, Bala.nus eburneus, and some Bala.nus balanoides (Stimp.); as well as the ubiquitous littorines, Littorina irrorata. The Balanus community was small, however, and as usual, the number of specimens per unit area increased as one approached the end of the region. A species of mollusk which had not been collected previously was abundant here. It vvas a small species called the bubble shell, Bulla occidentalis. It inhabited only rocks on which Cladophora was growing, but egg masses were found on loose stems of eelgrass, Zostera marina, which had floated in from another locality. This mollusk is one of the type which appears to have more body than it can draw back into its shell. In fact, as it grows older its body gradually engulfs the shell, which is well-formed, until this mollusk resembles the true nudibranchs, its near relatives. A tube-dwelling annelid was collected from floating eelgrass blades, as well as from Sargassum fronds. This was the minute worm Spirorbis spirillu.m, whose coiled tubes were only one millimeter across. Often there were over one hundred tubes on a single leaf blade. On empty shells found in the area were empty tubes of another annelid, Serpula vermicularis. These are much larger and thicker tubes than those made by Spirorbis. Some shells collected also had colonies of the bryo­ zoan Acanthodesia savartii. These bryozoans belong to the phylum Molluscoidea, which contains many animals of un­ certain classification. Another bryozoan, Membranipora tehuelcha, was found incrusted on a dead stem. A rock, taken from between the boulders at a station much farther out on the jetty, was covered with live bryozoans classi­fied as Membranipora m€1nbranaceae (Linnaeus). This colony was six centimeters in diameter, and had the texture of a sea anemone. It was the only living colony found. Another interesting but rare species seen here wa~ the small "wing-footed" pelagic mollusk, Clione papillion­aceae. This species has no shell nor mantle, and is trans­parent. The wing-like appendages are lobes of the foot. Only three specimens were collected. Sargassum washed in at this station contained many of the unidentified nudibranch mollusks found at Sabine, and also some eggs of the snails. Also abundant was the smaller nudibranch, Aeolis, sp. The small sea anemone, Sagartia luciae Verrill, was found on most of the Sargas­sum, as was the annelid Lumbrinereis tenuis. The sea horse, Hippocampus stylifer (Jordan and Gil­bert); the pipefish, Syngnathus floridae (Jordan and Gil­bert); and the sargassum fish, Histrio histrio (Linn.), were all found in the gulfweed which was unusually abundant among the rocks. Pipefish were nu.i~erous, but only a few of the other fish listed were caught. All these fish are easily caught by bringing a fine-meshed dip-net up from beneath the water, collecting the gulfweed with the fish intact. Pipefish jerk themselves free from the Sargassum when it is raised out of the water, and resemble small arrows shot out in all directions. The sargassurn fish is 68 a peculiar fish found only in Sarga.ssum, and those specimens collected were small ; climbing about among the gulfweed and resembling frogs. Their fins are modified for this purpose. A related species is called the frog fish, Antennarius ocellatus. No other fish were caught at this station. This section of the jetty was often the "landing field" for the brovm pelican, Peleca.nus occidentalis, although these birds do not feed near the jetties. Birds which were always present were the cormnon tern, Sterna hirundo; and the laughing gull, Larus atricilla. Tiger beetles, Cicindela dorsalis, were common but were not as plentiful as they had been on the asphalt cap of the Galveston jetty. STATIONS 35+94 to 64t50, (Wide Concrete Area). The flora and fauna of this area were similar to that of the preceding section. The only condition of topography that was different in this area was the opat water to the north replacing the sand on St. Joseph Island which was typical of that section. No new species were found, and the communities remained unchanged. STATIONS 64+00 to 119-t50, (Rock Area) This large section was taken as a unit because the life forms were the same over the entire forty-five-hundred feet to the end. One difference in structure of the jetty at this point is a group of spurs, shown in figure IX. These spurs are of various lengths, the maximum being two­hundred-fifty feet. The purpose of these small break­waters is to protect the jetty proper, which was at one time threatened by the natural deepening of the channel too near the toes of the north jetty. These spurs are composed of the same granite rock that forms the main jetty, and therefore the fauna is not changed by them. There was considerably more drift on the spurs than on the jetty when the writer last collected there, but this was due to a recent squall on the Gulf. The greater abundance of Sargassum was also caused by this squall. In this area were found purple floats of many Portu­guese man-of-war jellyfish, Physalia physalis (Linn.). Those collected were still alive and ranged in length from four to sixteen centimeters. These coelenterates were more numerous on the beaches at Aransas Pass, along with the "cabbage-head" jellyfish, Stomolophus meleagris. Both of these species are pelagic forms. Other jellyfish collected included three species of Aurelia. The only one classified was Aurelia aurita (Linnaeus), which was found in quieter water between the rocks. ::Phe comb jelly, Bolinopsis microptera (L. Agassiz), was also found in small numbers. Several tangled masses of red and yellow coral-like animals, (two species), commonly known as "sea whips'' were found stranded among the rocks. These colonial sea whips had floated in, but many species of animals worthy of ob­ servation were found attached to them. Large goose barn­ ?O acles, Lepas anatifera Linnaeus, ·which measured four centimeters in length, were collected. Lepas pectinata was growing on several of the "whips". One box-crab Of the genus Lopholithodes, and several young crabs were engaged in freeing themselves from the tangled "whip". A few Omphid worm tubes had attached themselves to it. Three echinoderms were collected in crevices of the jetty rocks. The most plentiful were the light-colored sand stars, Astropecten antillensis Lutken, which also covered the strand area after each high tide. The purple sea urchin, Arbacia punctulata {Lamarck), and living speci­mens of the sand dollar, Encope michelini (L. Agassiz), were found. Actually only the sea urchin lives on the jetty, while the other forms are brought in by the tides. Ecologically, this rocky area was a Balanus-Littorina community. Certain atations closely resembled the algae­covered rocks of Freeport. Besides the barnacles and lit­torines, the horse mussel, Mytilus hai"Ilatus; the limpet, Siphonaria lineolata Orbigny; and the abundant alga Padina pavoni, J. Ag., should be listed as secondary dominants. The arnphipod, Carinogarmnarus mucronatus was often pres­ent where Cladophora was growing. No isopods were fotnd. Few hermit crabs were seen, but the rock crab Menippe ~­cenaria was abundant. On the average, one of these crabs was seen about every six meters of the entire rock area of the jetty. Swimming crabs, or blue crabs, Callinectes sapidus; ?l and Arenaeus cribrarius Lamarck, were seen at intervals. Both adult and young shrimp of several species could be taken with a dip-net. Arnone those collected were the less familiar mantis shrimp, Squilla empusa. One species of spider crab, not yet identified, was also caught. This region contained an abundance of empty mollusk shells of the various species common to the beaches. Those collected from low pockets between rocks were as follows: the jingle shell, Anemia glabra; the bubble shell, Bulla occidentalis; the tooth shel~ Dentaliu.i.~ entalis; the bivalves Barbatia barbata L., and Lucina pennsylvanica Linne; and the oyster, Ostrea virginica Gmelin. The fol­lowing shells, when collected, usually contained hermit crabs: mitre shells, Mitra 'cinctella; turret shells, Tur­itella varigata; moon snails, Polinices duplicata Say~ dog whelks, Nassa acuta; lightning shells, Busycon per- L. / versum inne and Busycon pyrum Dillwyn; and the oyster drill shells Thais floridana Conrad, and Ursosalpinx cinerens. Beautiful floating shells of the purple snail were often collected in this area. The species Janthina communis was more abundant than the larger species, Janthina ezlobosa. This is a pelagic mollusk, having a very thin shell. The snail secretes a bubble-like gelatinous raft which keeps it afloat. It is a gregarious animal, and one usually f:inds it either abundant or entirely absent in a given locality. Those collected were living, although empty shells were numerous on the nearby beach. 712 One large nudibranch, Navinax inermis, was found on a rock of the jetty, and another was caught with a net in the same locality by a shrimp fisherman. Both specimens were ten centimeters long, eight centimeters broa~ and eight centimeters high. On several occasions, the writer seined the water adjacent to both sides of the jetty at this section. This was done with the assistance of "Scotty" Ulch, a fisherman who was familiar with the fauna of the area. An effort was made to collect only the specimens near the jetties, but the following list of species collected includes sev­eral pelagic fish: The most numerous species were the mullet, Ivfugil c eph­alus Linnaeus; the moonfish, Vomer setapinnis Mitchill; the porgy, Calamus arctifrons Goode and Bean; the pompano, Trachinotus carolinus (Linnaeus); and small specimens of drum, Pogonias cromis (Linnaeus), and tarpon, 'I1arpon atlantic­~ (Cuvier and Valenciennes). Other species represented by 1 smaller numbers were: the lookdown, Selene vomer; the 1At least five fish of each of the species listed were collected at this station. triggerfish, Balistes capriscus (Gmelin); the batfish, Ogcocephalus, sp.; the striped sole, Achirus lineatus Lin­naeus; the flounder, Paralichthys lethostigmus (Jordan and Gilbert); the angelfish, Chaetodiuterus faber {Broussonet); 73 the ribbonfish, Trichinurus lepturus Linnaeus; the common skate, Raja erinacea Mitchill; the round stingray, Urobatis sloani (Blainville); the sea robin, Prionotus pectoralis· (Nichols and Breder); the cowfish, Lactophrys tricornis Linnaeus; the spiny boxfish, Chilomycterus schoepfin (Wal­baum); and the swellfish, Spheroides spengleri (Bloch). Common arthropods in this collection included the red-tailed shrimp, Penaeus brasiliensis; the common shrimp, Penaeus setiferus; and other shrimp, Penaeus aztecus, 1a.nd Xiphopenaeus kroyeri; and the crabs Callinectes sapidus, Arenaeus cribrarius, Ovalipes ocellatus, and Portunis pan-amensis. Less familiar species were the small decorator crab, Oregonia gracilis; an unidentified species of "Calico" crab; a large red hermit in a Busycon shell; and the mantis shrimp, Squilla (Chlorodella) empusa. Concerning the arthropods of the area, it is well to point out that the common shrimp is the only animal which has ever been scientifically investigated on the Gulf coast of Texas. For the past ten years the United States Bureau of Fisheries has carried on this investigation with the cooperation of the Game, Fish and Oyster Commission of Texas and similar commissions of other Gulf states. Most of the work has been done in the Aransas area. The other inffide shrimp-fishing grounds are located at Matagorda Bay, San Antonio Bay, Corpus Christi Bay, and West Bay. This is im­portant, since eighty per cent of the total catch of sea­ 74 2 foods of the Gulf in 1937 were shrimp. 2 · united States Department t>f Commerce, Bureau of Fish­eries Statistical Bulletins Nos. 1332 and 1344, (Washington, 1937). The chief factor of the Fisheries investigation center­ed around the distribution of shrimp in relation to salinity of the water. The red-tailed shrimp, Penaeus brasiliensis, was a typical shrimp investigated, and probably more is known of its life history at present than of any other species of animal found in the Gulf of Mexico. In Aransas Bay, young shrimp of this species come in from March until June, and then return to the Gulf by July. By June, young shrimp of the commercial species, Penaeus setiferus, are coming in. This species stays in Aransas Bay until fall. According to the technical investigations: (1) As shrimp grow larger, they seem to seek more and more salty water. This is what helps them in finding their way back to the Gulf which is their normal hab­itat as adults. (2) Only when actually moving from one place to another will they be found in any ~ype of bottom except that in which mud predominates. 3Annual Report of the Game, Fish and Oyster Commission, (Austin, Texas, fiscal year 1937-38), 32. The oyster situation is also being investigated, and results already obtained shnw that the oyster reefs have been 75 4 over-fished during the past thirty years. The writer is 4 Ibid., 29. cognizant of this fact from observation of the deposits of empty shells in several regions, as already mentioned. The jetties are not the natural habitat of the oyster, since oysters prefer a muddy bottom, but some marine inhabitants of the jetties have certainly helped the fishermen in de­stroying oysters of the region. These are the various snails such as Thais and Busycon, which include oysters in their diets. Floods should not be under-estimated, since they lower the salinity in some of the bays until these bi­valves are killed. Squalls, on the other hand, cover the oysters with mud and silt and suffocate them. It is evident that the oyster population will become diminished until steps are taken to cultivate oyster reefs as they should be. SOUTH JETTY STATIONS O+OO to 31+50, (End of Concrete) This section of the jetty on Mustang Island is border­ed on the south by the sandy shore, and capped with concrete. The concrete is widest from stations 14+60 to 31+50, and this section extends into the Gulf. As on the north jetty, however, there was no great difference in the abundance of any species found on the concrete section when compared with the rock area. The area capped with concrete was another typical 5 tidal, or intertidal, community composed of Balanus 5shelford prefers the term "tidal", since such a community "is evidently adjusted to, and probably requires, tidal rhythm." Frederic E. Clements and Victor E. Shelford, Bio-Ecology, (New York, 1939), 324. barnacles and Littorina irrorata snails. There were less than one hundred individuals of each genus per square meter. No algae were present, but other animals collected were the less common Littorj_na angulifera; the very small snail, Nerita versicolor Gmelin; and the limpet, Siphonaria lineolata Orbigny. There were never more than twenty in­dividuals of these species per square meter. A few large isopods, Ligyda exotica (Roux), were ob­served halfway out on this secti-on, but otherwise there were no important influents. Small fish, such as mullet and drum; and young shrimp of several species, could be caught in net-fuls. Gulls and terns were doing their part of the fishing for these young animals. Holes of the sand crab, Ocypode albicans, were found to be approximately one meter apart in every direction over the entire sandy area to the south. A few old wooden piles, protruding above water in this area, contained many holes, and when the wood was cut into with a knife, the mollusk, Martesia cuneiformis Say, w1s often found. A few specimens of the wood-boring isopod, Sphaeroma destructor, were also present. This was not the 77 same species as the one discovered at Galveston, but either species could probably be found in both localities, if a suitable type of wood were present. On the beach area to the south were found shells s imilar to those collected between the rocks of the north jetty. Some shells were incrusted with the corals, Astrangia, sps. Tests of sand dollars and starfish were plentiful; and several floats of Physalia physalis and Velella velella were collected at the toes of the jetty. There were several strings of capsules of the knoo bed conch, Busycon, sp., and ·dry clumps of so-called "red­grass" egg masses of Ursosalpinx, sps. The small been clam was plentiful. The species Donax variabilis, as its name suggests, was found in many color patterns. A few burrow­ing crabs, Emerita benedicti, were also collected. As indicated by small, smooth holes near the hinges, several bivalves had fallen prey to the oyster drill snails, Ursosalpinx and Thais. A check-up revealed that the three genera most molested were Arca, sps., Dosinia, sps., and Tellina, sp. It was further observed that egg cases of Ursosalpinx, sp. were fastened to some of these shells. Two less common mollusk shells found in this region were the olive shell, Oliva sayana Ravenel; and the sun dial shell, Solarium granulatum Lamarck. Insects formed a definite part of the animal population as far as station 31+50. Those found in appreciable numbers were green-eyed flies, Tabanus costalis; robber flies, Erax rufibarbus; tiger beetles, Cicindela dorsalis; and house flies, Musca domestica. STATIONS 31+50 to 86+50, (End of Jetty) The growth of algae increased gradually as one pro­ceeded toward the end of the jetty, the dominant species being Padina pavoni and Ulva lactuca. This was the f:ir st jetty where Ulva was found to be abundant. Some amphipods were found in the algae, and many small hermit crabs were present. Rocks of this area supported Balanus-Littorina­Mytilus lociations. It is interesting to note that one species of barnacle, Balanus balanoides Linne, is not found anywhere in the south except on rock jetties. All other species are commonly found on wood, as well as on rock surface. The principal inhabitants of rock crevices were the rock crab, Menippe mercenaria; and the sea anemone, Tealia crassicornis. Sargassum and other jetsam contained the same flora and fauna discussed previously. Floating spiral shells, Spirula spirula Linn{, were abundant in the debris. These empty shells were chambered in the same manner as the chambered nautilus. No living specimens were found, and some had floated so long that small goose barnacles had attached themselves to the shells. A small number of Thais snails inhabited rocks of this whole area, and many of their shells were used by hermit crabs. Several annelids were collected, but the 79 writer was unable to have them properly classified. The only species found in significant numbers, however, was Lumbrinereis tenuis. A few small jellyfish, Gonionemus murbachii, were caught. near station 70+50. A single species of striped jellyfish, Dactylometra quinquecirrha Desor, was also collected. This is a larger jellyfish having sixteen radiating, reddish-brown stripes. :F'ree-swimming arthropods and fish of this area were similar to those found at the end of the north jetty. They are omitted here to avoid repetition. SUMMARY PORT ARANSAS NORTH JETTY STATIONS 0+00 to 35+94, (Section of concrete-capped jetty having only the south side rocks exposed to water, five to fifteen feet deep). Species Common Name Number per Square Meter Balanus im:12rovisus Darwin. Barnacle 10 to 80 Balanus eburneus. Barnacle 2 to 30 Balanus balanoides (Stimp. ) • Barnacle 0 to 10 Littorina irrorata. Littorine 60 Bulla occidentalis. Snail 20 Clado;Ehora, sps. Alga (scarce) Spirorbis spirillum. Annelid tubes (100 tubes p~r leaf) Serpula vermicularis.Annelid tubes (on 10 shells) Acanthodesia savartii. Bryozoan (3 colonies) Membranipora tehuelcha. Bryozoan (on 4 stems) Membranipora membranaceae (Linn.) Bryozoan (on 1 rock) Floating Specimens: Clione papillionaceae. Wing-Foot Mollusk (3 collected) Sargassum, sps. Gulfweed (abundant) Unidentified Nudibranch 5 Aeolis, sp. Nudibranch 10 Sagartia luciae Verrill. Sea Anemone 15 Lumbrinereis tenuis. 30 Hippocampus stylifer(Jorda.n and Gilbert). Sea Horse (3 collected) Syngnathus floridae (Jordan and Gilbert). Pipefish 10 Histrio histrio (Linnaeus). Sargassum Fish (1 collected) Birds: Pelecanus occidentalis. Pelican (occasional) Sterna hirundo. Tern 6 Larus atricilla. Laughing Gull 6 Insects: Cicindela dorsalis. Tiger Beetle 10 STATIONS 35+94 to 64+50, [Section of wide concrete support­ ing identical life forms found in preceding area. Refer to above list of species, (Stations 0+00 to 35~94)]. STATIONS 64+50 to 119+50, (Rock area of north jetty extend­ ing into the open Gulf; water gradually increasing in depthfrom four feet to twenty-five feet at end of jetty}. Sargassum, sps. Gulfweed 4 Physalia physalis (Linn.) Man-of-War (dead specimens) Stomolophus meleagris. Jellyfish (dead spec:hnens) Aurelia aurita Linnaeus. Jellyfish 1 Aurelia, sp. Jellyfish ( 4 collected) 81 Bolinopsis microptera (L. Agassiz).(Jellyfish;} Comb Jelly ( 1 collected) Unidentified species, Sea Whip (3 large masses) 2 sps. Lepas pectinata. Goose Barnacle (covered one side of pl.ank which had washed ashore) Lepas anatifera. Goose Barnacle {16 collected) Lopholithodes, sp. Boi Crab (1 collected) Various species, young Crabs 1 Omphid, sp. ·worm tubes 1 Astropecten antillensis Lutken. Sand Star 20 Arbacia punctulata (Lamarck). Sea Urchin 2 Encope michelini (L. Agassiz).{Sand Dollar;) Key-Hole Dollar (5 living specimens collected) Balanus improvisus and B. eburneus. Barnacles 30 to 100 Littorina, sps., mostly L. irrorata.LittorineslO to 80 :Mytilus hamatus. Horse Mussel 10 to 50 Siphonaria lineolata Orbigny. Limpet 20 Padina pavoni J. Ag. Alga (abundant) carinogammarus mucronatus. Scud (10 per sq. meter in certain areas only) Menippe mercenaria. Rock Crab (1 every six meters) Callinectes sapidus. Swimming Crab 1 Arenaeus cribrarius Lamarck. Crab 1 Squilla empusa. Mantis Shrimp l unidentified Spider Crab (1 collected) Navinax inermis. Nudibranch (2 collected) Oregonia gracilis. Decorator Crab 1 Penaeus brasiliensis. Shrimp 10 Hepatus epheliticus. Spotted Crab (5 collected} Penaeus setiferus. Shrimp 6 Unidentified, large Hermit Crab (1 collected) Empty Mollusk Shells: Anomia glabra. Bulla occidentalis. Dentalium entales. Barbatia barbata L. Lucina pensylvanica Linn~. Ostrea virginica Gmelin. Mitra cinctella. Turritella varigata. Polinices duplicata Say. Nassa acuta. L. ~ Busycon perversum inne. Busycon pyrum Dillwyn. Thais floridana Conrad. Ursosalpinx cinereus. Janthina communis. Janthina globosa. Jingle Shell Bubble Shell Tooth Shell Bivalve Bivalve; Lucine Oyster Miter Shell; Mitra Turret Shell I\!Ioon Snail Dog Vlhelk Lightning Shell Lightning Shell Snail Snail Purple Floating Shell Large Purple Shell Pelagic Fish, caught within three meters off the jetty: Mugil cephalus Linnaeus. M:ullet Vomer setapinnis Eitchill. Moonfish Calamus arctifrons Goode and Bean. Porgy Thachinotus carolinus (Linnaeus). Pompano Pogonias cromis (Linnaeus). Drum Tarpon atlanticus (Cuvier and Valenciennes). Tarpon 83 Selene vomer. Lookdown Balistes capriscus (Gmelin). Triggerfish Ogcooephalus, sp. Batfish Achirus lineatus (Linnaeus). Striped Sole Paralichtys lethostigmus (Jordan and Gilbert). Flounder Chaetddipterus.faber {Broussonet). Angelfish Trichiurus lepturus Linnaeus. Ribbonfish Raja erinacea :Mitchill. Common Skate Urobatis sloani ·(Blainville). Round Stingray Prionotus pectoralis (Nichols and Breder). Sea Robin Lactophrys tricornis Linnaeus. Cowfish Chilomycterus schoepfin (Walbaum). Spiny Boxfish Spheroides spengleri (Bloch). Swellfish; Blowfish PORT ARANSAS SOUTH JETTY STATIONS 0+00 to 31+50, (Balanus-Littorina community on north side; sandy beach area on south side). Callinectes sapidus. Swimming Crab l Balanus improvisus. Barnacle 80 Littorina irrorata. Littorines 50 Littorina angulifera.Littorines 10 Nerita versicolor Gmelin. Snail 2 Siphonaria lineolata Orbigny. Limpet 20 Ligyda exotica. Isopod 1 various species of young Shrimp 10 Various species of Gulls 3 Tealia crassicornis. Sea Anemune (few collected, 1938) Arbacia punctulata. Sea Urchin (few collected, 1938, 1939) Penaeus brasiliensis. Shrimp 6 Astropecten antillensis Lutken. Starfish 16 Mugil cephalus. young Mullet 12 Various species of Terns 2 Wood Borers: Martesia cuneiformis. Isopod (10 per cubic foot of wood) Sphaeroma destructor. Isopod (14 collected) Empty Mollusk Shells: Oliva sayana Ravenel. Olive Shell; Purple Olive Solarium granulatum. Sundial Shell Anomia glabra. Jingle Shell Bulla occidentalis. Bubble Shell Lucina pennsylvanica Linne. Lucine Ostrea virginica Gmelin. Oyster Mitra cinctella. Miter Shell Turritella varigata. Turret Shell Polinices duplicata Say. Moon Snail; Shark Eye Nassa acuta.. Dog Whelk Shell Busycon perversum Linne. Lightning Shell; Oyster Drill Thais floridana Conrad. Snail Littorina irrorata. Littorine; Periwinkle Ursosalpinx cinereus. Snail Janthina communis. Small Purple Snail Janthina globosa. Large Purple Snail Beach lPorms: Donax variabilis. Bean Clam 30 Emerita benedict-i. Burrowing Crab 1 (more plentiful in 1938) Astropecten antillensis Lutken. (few living specimens) Starfish; Sand Star Encope michelini, Sand DolYar tests 3 Astrangia, sp. Coral . (incrusted on 10 shells) Physalia physalis. Man-of-War Jellyfish 1 Velella velella. Jellyfish floats 1 Busycon, sp. Snail eggs (15 strings observed) Ursosalpinx, sp. Snail eggs (numerous) Insects: Tabanus costalis. Green-Eyed Fly ·3 Erax rufibarbus. Robber Fly 3 Cicindela dorsalis. Tiger Beetle 10 Musca domestica, Housefly 0 to 60 STATIONS 31+50 to 86+50, {Rock area extending into the Gulf). Balanus balanoides Linne. Barnacles 10 Balanus improvisus. Barnacles 90 Littorina irrorata. Littorines 80 Padina pavoni. Alga (abundant) Ulva lactuca. Alga; Sea Lettuce (most abundant Alga) Carinogammarus mucronatus. Scud 11 Pagurus, sps. Hermit Crabs 1 Menippe mercenaria. Rock Crab 1 Dactylometra quinquecirrha Desor. Jellyfish (1 collected) Tealia crassicornis. Sea Anemone (clans of 8 to 10) Astropecten antillensis. Sand Star tests 1 86 Spirula spirula Linne'. Spiral Shell 1 Thais floridana. Snail 8 Lumbrinereis tenuis. Nereis Worm 1 Gonionemus murbachii. Jellyfish (5 collected) Unidentified Luminescent Bacteria or Protozoa (observed at night on jetty rocks) Note: This area was not seined, as was the correspond­ing area around the north jetty. Pelagic forms would prob­ably be the same in both regions. In 1939, the writer caught six squids of the species Loligo brevipennis, in this area. In 1938, the colonial disc-shaped coelenterate knovm as "sea pansy", or "sea liver", Renilla amethystina, was present in small numbers in the Aransas area, but not in the immediate vicinity of the jetty. The writer found neither of these species in 1940 at any jetty, except the Renilla at Freeport. 87 FIGURE X,A NORTH JETTY, PORT ISABEL Station 30•00, on Padre Island (Jetty Undergoine Repairs at Extrene End) FIGURE X,B SOUTH JETTY, PORT ISABEL station 25+00; Brazos Island Beach, Foreground CORPS OF ENGINEERS U.S.ARMY PT. ISABEL ISLAND JETTY 5330 FT LG. ISLAND JETTY 5092 FT. LG. :::;."'. :..""'. . . . . ~: · -P. ~-...· :. 0 .. , . . ·. /~~ ,:~ ..~ -..':;!f-'f.~1' D ·~­ ·~y.:. .. r'--,. >·'> .> "~.... .. :7:?}1{j ·:· '-~ \_/·· .: . -.::.;-J ),f .. ' . . ' .·'. .. 0;· ' . I ~·-~ ··' ~ :#~ - . . MAP No.v BRAZOS ISLAND HARBOR, TEX. CONDITION SEPTEMBER 30, 1939 SCALE IN MILE.S ~--k---l_ 1 ~ J@ FIGURE XI CHAPTER VIII THE PORT ISABEL JETTIES The Port Isabel jetties are approximately one-hundred­f ifty miles due south of the Port Aransas jetties. The Brazos-Santiago Pass, which these jetties protect, is located between Padre Island and Brazos Island. This is the first pass encountered south of Corpus Christi Bay, and is therefore the only southern pass between the Gulf of Mex­ico and Laguna l\1adre. Contrary to the popular belief of many people, the Rio Grande {River) does not flow into the Laguna Madre and thence through the Brazos-Santiago Pass. Instead, the mouth of this river is located on the Gulf itself, ten miles south of the Port Isabel jetties. NORT:rI JETTY As the accompanying map, figure XI, indicates, the north jetty is reached only by boat from Port Isabel or from Brazos Island. This jetty, extending due east into the Gulf, is approximately one mile long, and has no part capped with concrete. Both jetties have cross-ties and rails alone their entire lengths, supported by creosoted piles, as shown in figures X,A, and X,B. At the time of this 1Nriting, the track on the north jetty is being used to carry new granite cover rocks to a station near the gulfward end of the jetty. According to the engineer in charge of this repair work, these jetties require more repairs than any of the others. It was easy to see why this was the case, because in general, the undertow action of the waves was greater here than anywhere else on the Texas coast. This was part­ ly due to the fact that the Port Isabel jetties are geo­ graphically farther out in the Gulf. The range of tide was no greater than that of the other jetties, however, averaging one and one-half feet. One of the worst results of the strong wave action was the extreme turbidity of the water. It was at once apparent that the flora and fauna would be affected greatly. It was also learned that the fishing done in the area was mostly off-shore fishing. When repairs were in progress, fishing from the jetties was prohibited. The species of fish usually caught were trout, mackerel, tarpon, flounder, jev!f'ish and redfish. STATIONS O+OO to 10+00 The first thousand feet of the jetty borders Padre Island on the north, servinr, as a seawall. On the north side of the jetty, the only inhabitants of the sand were a few sand crabs, Ocypode albicans Bose.; and some Staphy­ linid scavenger beetles found near a dead fish. The area on the channel side was the most protected section of either of the Port Isabel jetties. The rocks, however, were acted upon by the sand in the extremely turbid water until they supported little life. A few periwinkles, Littorina ziczac Gmelin, were discovered, high above the level of the average wave, probably seeking to keep themselves protected from the grinding action of the sandy water. The only other species at this station was the edible crab, Callinectes sapidus, which did not seem to mind the turbid water. On the backs of six of these crabs were found large ivory barnacles, never more than two per crab. These barnacles measured three centimeters across, and were possibly of the species Balanus eburneus. STATIONS 10+00 to 10+15 This small section formed the beach area on the north side of the rocks. A domirnmt influent was the burrowing sand crab, Emerita benedicti (Sclh~itt). Yo1L~g specimens comprised about half the sand crab population. Only this single species of crab was collected here. A few bean clams, Donax variabilis Say, were collected. Three species of isopods were caught by seining the breakers as they washed the shore. These were Ancinus, sp., Sphaeroma destructor, and Sphaeroma quadridentatmn Say. Neither species was abundant, and all had their character­ istic folded-up appearance which was similar to that of the land species known as "pill bug". The writer made an effort to find these borers in the wooden parts of the railroad foundation, but since the piles were comparatively new, and had been creosoted, none were found. 'l'hree Portuguese man-of-war jellyfish, Physalia ~­ salis Linn., were stranded on the beach at this station; a few teats of the sand dollar, Encope michelini (L. Agassiz), were also present; and a beer bottle washed ashore was covered on one side with barnacles, Lepas anatifera Linn­ae1J.S. On some empty mollusk shells were found the coral, . AS~ t rang1a, sp.; while broken, loose pieces of another coral, Astrae argus, were dug out of the beach sand. STATIOiTS 10+15 to 53+30, {End of Jetty) The greatest difference in fauna of any region was observed at this section. lnstead of the usual abundance of Balanus and Littorina, there were only a few, scattered individuals of each, and they were all on inside rocks. Many of the Balanus improvisus Darwin specimens ex&1nined were found to be only empty shells, but they were usually large. On the entire jetty, only about thirty Thais snails were seen, and about the saJlle number of hermit crabs, Pagurus pollicaris. ·At the end of the jetty there vms a slight growth of Cladophora fascicularis (;j_ertens) Kutz. Repair work was in progress at the extreme gulfvmrd end. Two species of living mollusks were collected at this station v1hich had not been seen at any other jetty. One is knovm as a helmet snail, Cassis sulcosa, and the other a bandshell, Fasciblaria distans Lamarck. Both are prized by souvenir collectors, and this is one reason why they are seldom seen on the beach. They are also less comrron than most species found near the shore. Empty mollusk shells found on the beach and ainong 93 the jetty rocks, at intervals, were as follows: the moon shell, Polinices duplicata Say; the olive shell, Oliva sayana Ravenel; the bandshell, Fasciolaria distans, in broken fragments; the helmet, .Cassis sulcosa; the conch shell, Thais floridana Conrad; the lightning shell, Busycon perversum Linne, and its egg capsules; the ear shell, Sigaretus perspectivus Say; the heart shell, Cardita floridana; dosinia shells, Dosinia discus Linne, Dosinia ponderosa, and Dosinia elegans Conrad; the ark shells, Arca transversa Say, Arca camnechiensis Gmelin, and Arca elegans Conrad; and other bivalves, Lucina crenulata Con­rad, Anatina plicatella Lamarck, Asaphis deflorata Linne, Lucina pensylvanica Linne, Noetia ponderosa Say, and Plagiocteniurn gibbus Linne. SOlmi JETTY The south jetty is approximately two thousend feet south of, and runs parallel with, the north jetty. The jetties are identical except that the south jetty is two­hundred-forty feet shorter. Examination of the life on this jetty indicated that it was similar to that on the north jetty, and although the writer made close observations, no new forms were found on the south jetty. For this reason, a repetition of the life forms of the north jetty will not be made here. Stations' numbers are comparable, except that the beach area of the south jetty is between stations 9+?0 and 9+80. SUMMARY PORT ISABEL JETTIES STATIONS 0+00 to 10+00, North Jetty, (Sandy area on north side and channel area on south side; water five to ten feet deep on channel side, STATIONS O+OO to 9+70 form corresponding areas on South Jetty). Species Common Names Number per Square Meter Ocypode albicans. Sand Crab 1 Staphylinid Beetles (25 observed) Littorina ziczac Gmelin. Littorine 5 Callinectes sapidus. Swimming Crab 1 Balanus eburneus. Barnacle (10 collected) Balanus_improvisus Darwin. Barnacle 1 STATIONS 10+00 to 10+15, North Jetty, (Beach area on north side. STATIONS 9t70 to 9t80 form corresponding areas on South Jetty). Emerita benedicti (Schmitt). Burrowing Crab 10 Donax variabilis Say. Bean Clam 2 Ancinus, sp. Isopod 6 Sphaeroma quadridentaturn Say, Isopod 1 Sphaeroma destructor. Isopod (3 collected) Physalis physalis Linn. Man-of-War (3 collected) Jellyfish. Encope michelini (J. Agassiz) Sand Dollar 1 Le;pas anatifera Linnaeus. (80 on floating bottle) Goose Barnacle Astrangia, sp. Coral (on l? shells collected) Astrae argus. Coral (3 pieces collected) Empty Mollusk Shells: Lucina crenulata Conrad, Lucine Shell Anatina plicatella Lamarck. Asaphis deflorata Linne. Cardita floridana. Lucina pensylvanica Linne. Sigaretus perspectivus Say. Noetia nonderosa Say. ,, Plagioctenium gibbus Linne. Arca transversa Say. Arca campechiensis Gmelin. Arca incongrua Say. Dosinia discus Linne. Dosinia ponderosa. Dosinia elegans Conrad. Busycon perversum Linnl. Busycon, sp. egg capsules Thais floridana Conrad. Polinices duplicata Say. Oliva sayana Ravenel. Fasciolaria distans. Cassis sulcosa. Anatina Shell Bivalve Heart Shell Lucine Shell Ear Shell Bivalve Bivalve Transverse Ark Ark Shell Ark Shell Discus Shell Heavy Dosinia Dosinia Shell Lightning Shell Lightning Shell Snail Moon Snail Olive Shell Bandshell fragments Helmet Shell Two unidentified specimens of bivalves Note: Arca and Dosinia were the only genera represent­ed by great numbers of shells. STATIONS 10+15 to 53f30, North Jetty, (Rock area in open Gulf; water ranging in depth from six to twenty feet. STATIONS 9t80 to 50+92 form corresponding areas on South JettyJ. 96 Littorina ziczac Gmelin. Littorine 3 Balanus improvisus Darwin. Barnacle 8 Cladophora fasciolaris. Alga (scarce) Cassis sulcosa. Helmet Snail 1 Fasciolaria distans Lamarck. Bandshell (10 collected) Thais floridana Conrad. Snail (30 observed) Pagurus pollicaris. Hermit Crab (20 observed) CHAPTER IX CONCLUSIONS From the study of all available literature on the sub­ject, one is forced to conclude that the ecological surveys of marine communities in North America have been confined largely to the Pacific coast. The surveys on the Atlantic coast have been made almost invariably in the north. These investigations have been carried on by Shelford, Allee, Beauchamp, Colton, Pearse, and others, using various methods of interpreting results. Shelford prefers the stressing of large units and their subdivisions, while others emphasize 1 small units, or the habitat as a unit. It is apparent 1v.E. Shelford, "Some Marine Biotic Communities of the Pacific Coast of North America," Reprint from Ecological Monographs 5: 249-354, July 1935, p. 325. that data taken from such investigators have proved difficult of comparison. In the case of this thesis, the ·writer finds his ovm data hard to compare with those of other investigators for the following reasons: 1. The range of tide along the entire Texas coast is slightly above one and one-half feet. On the Pacific coast the range of tide is much greater, affording a large inter-tidal, or strand area. 2. The biotic communities on the Pacific coast include some natural rocky areas; while the jetties produce second­ary, or man-made communities differing from any natural habitats found on the Gulf bordering Texas. 3. The coast of the Gulf of Mexico now being considered borders an inclosed gulf .which differs from any other, es­pecially in its wind currents and gulf-tide currents. Thus, the geographical and topographical conditions are very un­like those investigated by Shelford and others. 4. The jetties themselves are isolated units, which, although similar in construction, cannot be discussed in ecological terms which designate one entire region as a unit. Furthermore, the area of each jetty is too small to be ex­pressed by an ecologic·al term comparable to terms ordinarily 98 2 applied to larger areas on the Pacific coast, for exampie. &v-. E. Shelford, "Basic Principles of Classification of Communities and Habitats and the Use of Terms," Reprint from Ecology, Vol. XIII, No. 2, April, 1932, p. 111. The writer, therefore, has used only the term "community", unless the animals being considered were found in separate, small, tidal or subtidal areas. In such cases, the term "clan" and "lociation" have been used, and when used they include mainly sedentary and sessile forms. 5. The entire littoral region of the Gulf coast, if examined ecologically, would necessarily be discussed as a sandy area; and in comparing it with another large region, the rocky jetties would play a minor part. This thesis, on the other hand, was written primarily to describe these rocky areas, and thus it must refer to beach forms as in­fluents on the jetties, although they are dominant forms of the Texas coast. With the above limitations in mind, the writer feels free to designate each jetty as a Balanus-Littorina can­munity, which was in most cases stable. In time, these jetties may become climax communities composed of at least these two genera of animals. This is more probable in Texas than in many other places because of the range of tide. It is undoubtedly true that many sessile barnacles of other regions are killed by desiccation due to extreme tidal fluctuations; but the writer has concluded that those barnacles found dead on rocks of the jetties investigated had been killed by excessive turbidity caused by strong wave action on sand. This was especially noticeable on the Port Isabel jetties, where turbidity was greatest, and Balanus population smallest, of any jetty investigated. In listing principal subdominants, those observed at various stations of the different jetties were found tru fluctuate both quantitatively and qualitatively. It is possible, however, to list the following species as being "always present" as subdominants: the rock crab, Menippe mercenaria; the swimming crab, Callinectes sapidus; the hermit crabs, Pagurus, sps.; the snail, Thais floridana; the limpet, Siphonaria lineolata; and several species of Cladophora and Enteromorpha algae. Occasional and rare species, although plentiful at times, play no important part in determining the fauna of large communities; but for the benefit of the reader, a complete check list of the species collected has been included in the appendix. The "occasional" species mentioned above may be pres­ent because of recent storms, spawning periods, seasonal migrations, changes in direction of wind or tidal currents, and unusual abundance of Sargassum. on the jetty rocks. Some of these forms may remain alive for weeks within pockets formed among the rocks, and one wonders whether or not it may be possible that a few have drifted from long distances, even as far as the Caribbean Sea. A number of species included were those found in the ecotone, or transition community between the pelagic and benthic areas of the Gulf. Some animals in this category are the shrimp, which have already been discussed in regard to their migration at spmvning time; and fish, many of which are in the larval stage when collected. Thus, ecotones may exist in both vertical and horizontal distributions, as in­ dicated above; but the writer has used the term "tidal" to apply to all cormnunities of non-motile forms which were found in the inter-tidal region. Few of the mollusk shells included in the lists belonged to littoral animals. Many of them may have been washed in from long distances, or from great depths. These shells are included, however, because in some cases they are indicative of the mollusks inhabiting the benthic area surrounding the jetties. This also applies to the tests of certain echinoderms and 'WOrm tubes found on beaches. The benthic area of the jetties, located in lower strata than the writer investigated, is a definite part of any complete survey, and the deep-water species included in the check-list are indicative of other similar forms which could be collected with dredging equipment suitable fa: use in water twenty feet deep. I.1ethods of sampling the sea-bottom in our country are now largely in the experiment al stage and expensive to undertake. The reader is referred to an article by :B'rances Kirsop, who makes the following 3 statement: 3Frances Mullis Kirsop, "Preliminary Study of Methods of Examining the Life of the Sea Bottom," Publication of the Puget Sound Biological Station, Vol. 3, Ho. 64, p. 129. We know of few attempts in American waters to gain accurate knowledge of the quantity of life per unit area of sea bottom. A systematic survey for quantity would likely lead to results as valuable as those secured by the Danish Biological Station at which extensive studies have been carried on••• Naturally this prel:iminary work is largely a matter of apparatus and methods. It is hoped that the benthic areas of the Gulf coast of Texas may be investigated by use of diving suits and dredges; but as pointed out in the above article by Frances 102 Kirsop, unless definite contour lines are laid off, and samples taken under prescribed scientific directions, very 4 little quantitative data can be obtained from benthic areas. 4 Ibid., 131. Bottom sampling is only one of the many fields waiting for investigation in the Texas area. Other studies for the ecologist include: Effects of salinity fluctuations on animals of the bays, including floods and Gulf disturbances. Salinity tolerance of fresh-water and brackish-water species encountered on the coast. Effects of turbidity on certain animals inhabiting the bays, especially the sessile forms. Effects of temperature and seasonal changes on the lives and activities of jetty forms. Life histories, including the spawning habits, of cer­tain animals in the area, (such as the studies already made of the common shrimp, as already described). Life histories of animals found exclusively on rocks, such as Balanus balanoides. Comparisons of jetty habitats with Gulf and bay habitats. Advantages and disadvantages of the jetties to fish and other animals in the immediate vicinities. Interactions and coactions of the flora and fauna of the region. All of these are broad subjects; any one would prove to be an interesting and useful piece of research which has not been undertaken in this area. If and when a biological station is established on the Texas coast for such investigations of marine life, the writer is inalined to prefer the Port Aransas area to any other on the Gulf proper. The greater number of species and individuals in the region is mainly due to the geogra­ phy and topography of the area; especially noticeable in the number of bays and passes near at hand. In conclusion, it is well to point out that the gov­ernment jetties, although built by man, supply rocky hab­itats for certain communities of animals and plants which would otherwise find no rocks for attachment and growth. Even though the jetties were constructed in comparatively recent years, they are to be maintained as permanent breakwaters; and no doubt, they will remain the exclusive rock communities of the Texas outer coast for years to come. For this reason, it is logical to assume that nnny future ecological studies will be centered around these jetties; and it is the hope of the writer that these in­ vestigations will not be delayed further. 104 BIBLIOGRAPHY Primary Sources Books Breder, Charles M., Jr., Field Book of Marine Fishes of the Atlantic Coast from Labrador to Texas, New York. lQ: P. Putnam's SonS-,,-1929, ~ Clements, Frederic E., and Victor E. Shelford, Bio-Ecology, New York. (John Wiley and Sons, Inc.}, 19"5'9:' Johnson, Myrtle E., and Harry J. Snook, Seashore Animals of the Pacific Coast, New York. (The Macmillan Company), 1927. Ricketts, Edward F., and Jack Calvin, Between Pacific Tides, Stanford University, California. (Stanford University Press), 1939. Bulletins and Yearbooks Cross, J. c., and Hal B. Parks, "Marine Fauna and Sea-Side Flora of the :Nueces River Basin and Adjacent Islands," Bulletin of the Texas College of Arts and Industries, Kingsville, Texas, March, 1937. Dall, William Healey, "A Preliminary Catalog of the Shell­Bearing Marine Mollusks and Brachiopods of the South­Eastern Coast of the United States, with Illustrations,m Bulletin of the United States National Museum, Wash­ington. \Government Printing Office), 1889. Game, Fish and Oyster Commission of Texas, Annual Report for the Fiscal Year 1937-38, Austin, Texas, 1938. Kirsop, Frances Mullis, "Preliminary Study of Methods of Examining the Life of the Sea Bottom," Puget Sound, Publication of the Puget Sound Biological1 Station, vol. 3, No. 64, 1922. Shelford, V. E., et. al., "Some Marine Biotic Communities of the Pacific Coast of North America," Ecological Monographs, 5: 251-345. (University of Illinois), 1935. Shelford, V. E., "Ways and Means of Improving the Quality of Investigations and Publications in Animal Ecology," Reprint from Ecology, Vol. XI, No. 1, (University of Illinois), 1939, 105 Shelford, v. E., "Geographic Extent and Succession in Pacific North .American Intertidal (Balanus) Com­munities," Contribution from the Zoolorical Lab­oratory of Illinois University, 363. University of Illinois), 1939. Shelford, v. E., "Basic Principles of the Classification of Connnunities and Habitats and the Use of Terms," Reprint from Ecolog)' Vol. XIII, No. 2. (Uni­versity of Illinois , 1932. United States Department of Connnerce, Memorandum I-134C, "Fish and Shell-l!'ish of the Gulf States," Washington. (Government Printing Office), 193?. United States Department of Commerce, Statistical Bulletin 1332, Vlashington. (Government Printing Office), 1937. Tinited States Department of the Interior, Statistical Bulletin 1344, Washington. (Government Printing Office), 1938. Maps Gulf Ii'ishgide Ivlaps, Gulf Oil Company Fishgide Bureau, Houston, Texas. Project Maps of the United States War Department, Office of the District Engineer, Galveston, Texas. Reprints by E. G. Cain Blueprint Company, Galveston, Texas. Letters Personal Letters from Staff of the Smithsonian Institution: Letters from Dr. Clarence R. Shoemaker, ·dashington, D. c., May 23 and May 31, 1940. Secondary Sources Books Arnold, Augusta 1!"1oote, The Sea-Beach at Ebb-Tide, New York. (The Century Company), 1901. Binney, w. G., A Manual of American_Land Shells, Washington.(Govermnent Printing Office), 1885. Buchsbaum, Ralph, Animals Without Backbones, Chicago. (Uni­versity of Chicago Press), 1938. Crowder, William, Dwellers of the Sea and Shore, New York. (The Macmillan CompanyT, l935-.-­ Hesse, Richard, w. c. Allee, and Karl P. Schmidt, Ecological Animal Geography, New York. (John Wiley and Sons, Inc.), 1937. Jordan, David Starr, and Barton w. Evermann, .American Food and Game Fishes, Hew York. (Doubleday, Page and Coll­panyl,1905. Mayer, A. G., Ctenophores of the Atlantic Coast of North America, Washington, D. c. (Carnegie Institution), 1912. Murray, George, An Introduction to the Study of Seaweeds, New York. ""{Macmillan and Company), l895-.- Miall, L. c., The Natural History of Aquatic Insects, London. (Macmillan and Company, Limited), 1912. Richards, Horace G., Ailimals . of the Seashore, Boston. (BruceHumphries, Inc.), 1938. ---~­ Stephenson, Thomas A., British Sea Anemones, Volumes I and II, London. (Printed for the Ray Society), 1935. Stebbing, T. R. R., Das Tierreich, 21: Amphi~oda, Berlin. (Verlag von R. Friedl~nder und Sohn), 1 06. Taylor, William R. , The Iviarine Algae of Florida with syecial Reference to the Dry Tortugas, v'Vashington, D.C. The Carnegie Institution), 1928. Bulletins and Unpublished Theses Bush, Mildred, "Revised Key to the Echinoderms of Friday Harbor," Publication of the Puget Sound Biological Station, 2: 17-44, Friday Harbor, Washington, 191B. Collier, R. G., "A Survey of the Vlater Fauna of Houston and Its Vicinity and an 1'\.nalytical Study of Its Use in rreaching Biology," Unpublished Master's Thesis, Austin, Texas. (University of Texas Library), 1939. Evermann, Barton w., and William c. Kendall, "The Fishes of Texas and the Rio Grande Basin Considered Chiefly with Reference to their Geographic Distribution," Published in Volume XII, Bulletin of the United States Fish Commission, Washington, ~c:---rGovernment Printing Office), 1894. 107 Gowanloch, J. N., "Fishes and Fishing in Louisiana," Bulletin 23, Louisiana Department of Conservation, New Orleans, Louisiana, 1933. Johnson, Charles Willison, "List of Marine Mollusca of the Atlantic Coast from Labrador to Texas," Pro­ceedings of the Boston Society of Natural History, vol. 40,No.l, Boston, 1934. Jordan, D. s., Barton w. Evermann, and H. w. Clark, "Check List of Fishes and Fishlike Verte~rates of North and Middle .America, North of the Northern Boundary of Venezuela and Colombia," Renert of the Commissioner of Fisheries, Part II, Washington,15:" c. (Government Printing Office), 1928. Pilsbry, Henry A., and E. G. Vanatta, "Marine Mollusca," Proceedings of the Washington Academy of Sciences, Volume N, Washington, D.C. (The Academy), 1902. Smith, Beulah s., "A Study of the Algae of the Gulf Coast of Texas," Unpublished Master's Thesis, Austin, Texas. (University of Texas Library), 1939. Shelford, V. E., and E. D. Towler, "Animal Communities of the San Juan Channel and Adjacent Areas," Contri­butions from the Puget Sound niological Station and the university of Illinois, 269. (University of --­Illinois), n.d.~ Tharp, B. c., "Structure of Texas Vegetation East of the 98th. Meridian," University of Texas Bulletin 2606, (University of Texas), 1926.~ Texas Game, Fish and Oyster Commission Bulletin 5, "Fishes of Texas," Austin, Texas, 1932. United States Department of Commerce, Investigational Re­ port 21, "Shrimp Industry of the South Atlantic and Gulf States," VIashington, D.C. (Govermnent Printing Office), 1934. United States Department of Commerce, Administrative Report 35, "Progress in :Biological Inquiries," Washington, D. c., (Government Printing Office), 1938. United States Department of Commerce, Bureau of Fisheries Document 890, "The Oyster and the Oysterindustry of the Atlantic and Gulf Coasts,n Washington, D. c. (Government Printing Office), 1920. Webb, Walter F., "A Handbook for Shell Collectors,'' Bulletin, Rochester, New York. (n. p.), 1935. APPENDIX CHECK LIST OF SPECIES Note: Species preceded by an asterisk (*) were verified by the Smithsonian Institution, Vlashington, D. c., 1940. Only specimens collected by the writer are listed. ANTh1AL KINGDOM PHYLUM PORIFERA (Unidentified "rock sponge") PHYLUM COELENTERATA Class Hydrozoa Order Leptoliniae :Family Campanulariidae Obelia dichotoma (L.) Hydroids *Clythia cylindrica Agassiz. Family Sertulariidae *sertularia versluysi :i>Jutting. Hydroid Family Plumulariidae *Aglaophenia minuta 111ewkes. Hydroid Order Trachomedusa Family Petasidae Gonionemus murbachii. Jellyfish Order Siphonophorae Fan1ily Velellidae *velella velella (Linn.) Sail Jellyfish Family Porpitidae Porpita linneana. Sea Pansy Family Physaliidae *Physalia physalis (Linn.) Portuguese Ivian-of-War Jellyfish. Class Scyphozoa Order Discophora Family Pelagiidae Dactylometra quinquecirrha Desor. Striped Jellyfish Family Stomolophiidae Stomolophus meleagris. Jellyfish Stomolophus, sp. Family Aureliidae Aurelia aurita (Linnaeus). Jellyfish Aurelia, sps. Class Anthozoa Order Pennatulacea {Unidentified "sea pen" or "sea whip") Yellow and Purple Species. Family Renillidae Renilla amethystina Verrill. Sea Liver; Sea Pansy Order Gorgonaceae Family Plexauridae Eunicea, sp. Gorgonian Coral Order Actiniaria Fa.~ily Sagartidae Tealia crassiformis. Sea Anemones Tealia, sp. Sagartia luciae Verrill? sagartia, sp. Order Madreporaria Family Astrangidae Astrangia danae. Coral *Astrangia, sp. Astrae argus Class Ctenophora (PHYLUM CTENOPHORA) Order Lobata Family Bolinopsidae Comb J"ellies Bolinopsis microptera {L. Agassiz)? Mneiopsis, sp. PHYLUM MOLLUSCOIDEA Class Bryozoa (Polyzoa) Order Chilostomata {Gymnolaemata) Family Bicellariidae Bugula turrita. Bryozoan Family Membraniporidae Membranipora mern.branaceae (Linnaeus) Membranipora tehuelcha *Acanthodesia savartii Savigny-Audouin PHYLUM ANNELIDA (.Al-Il'IULATA ) Class Chaetopoda Order Polychaeta Family Nereidae Lumbrinereis tenuis. Hereis Worms Nereis pelagica Nereis virens Nereis, s:ps. Family Polynoidae Lenidonotus polynoe. Le,pidonotus Worms Lepidonotus, sps. Family Leodicidae *Omphid, sp. (tubes). Tube Vlorm Family Serpulidae Serpula vermicularis. Spiral-Tube Worms *Serpula, sp. *Spirorbis spirillum? PHYLUM MOLLUSCA Class Pelecypode Order Prionodesmacea Family Ostreidae *Ostrea virginica Gmelin. Common Oyster Family Pectinidae Pecten gibbus (Linn6). Scallop *Plagioctenium gibbus Linne Family Aviculidae Pinna seminuda. Fan Shell Family Anomiidae Anomia glabra. Jingle Shell *Spondylus americanus Lamarck Family Mytilidae Mytilus hamatus. Horse Mussel *Brachidontes (Ischadium) recurvus Raf. Lithophaga plumula Henley. Date Mussel Family Carditidae Cardita floridana. Heart Shell Family Cardiidae *Trachycardimn (Dinocardium) robustum Selander. Cockle Shell Cardium magn.um. Cardium serratum. Family Tellinidae *Tellina alternata Say. Sun Shell Family Vereridae Dosinia ponderosa. Heavy Dosinia Dosinia elegans Conrad. *Dosinia discus Linne. Discus Shell *venus campechiensis Gmelin. Venus Shell venus mercenaria Linne. Family Petricolidae Petricola pholidiformis. Small Angelwing Family Arcidae *Arca campechiensis Gmelin. Ark Shells *Arca transversa Say *Arca incongrua Say *Barbatia barbata L. *Noetia ponderosa Say Family· Donacidae Donax tumida. Bean Clam *Donax variabilis Say *Asaphis deflorata Linne Family Psammobiidae *Tagelus gibbus Spengler. Jack-Knife Clam Family Solenidae Solen vagina. Clam Family Pholadidae *Barnea costata Linne'. Large Angelwing *liAartesia cuneiformis Say. Boring Mollusk Family Teredidae *Bankia (Bankiella) gouldi Bartsch. Shipworm Family Lucinidae *Lucina pensylvanica Linn~. Lucine Lucina crenulata Conrad Suborder Anatinacea Family Anatinidae *Anatina plicatella La..111arck Class Scaphopoda Family Dentaliidae Dentalium entales. Tooth Shell Class Gastropoda Order Fteropoda Family Clionidae Clione papillionacea. Vling-Foot Mollusk Order Opisthobranchiata Family Bullariidae Bulla occidentalis. Bubble Shell Family Aglajidae Navanax inermis (Cooper). Striped Mollusk Suborder Nudibranchiata Family Aeolidiadae Aeolis, sp. Nudibranch (Unidentified nudibranch) Order Pulmonata Suborder Geophila Family Helicidae *Polygyra texasiana Morie. Land Snail Suborder Orthodonta Family Olividae Oliva littera.ta (Lam. ) Olive Shell *Oliva sayana Ravenel Family Mitridae Mitra cinctella. Miter Shell *Anachis, sp. Family Fasciolariidae Fasciolaria distans Lamarck Family Nassidae Nassa acuta (S.) Dog ·whelk Family Cassididae Cassis sulcosa. Helmet Family Turbinellidae *Busycon (Fulgar) perversum Linne. Whelks *Busycon {Fulgar) pyrum DillWYn Family Muricidae Purpura haemostoma. Oyster Drill Snail Order Ctenobranchiata Suborder Orthodonta Family Muricidae Ursosalpinx cinereus (Say). Oyster Drill *Thais floridana Conrad. Suborder Streptodonta Family Naticidae Sigaretus perspectivus Say. Ear Shell Family Janthinidae Janthina communis. Violet Snail Janthina globosa. Large Violet Snail Suborder Pectinibranchiata Family Turritellidae Turritella varigata. Tower Shell Family Cypraeidae Cypraea gangraenosa Selander. Covrry Family Littorinidae Littorina irrorata. Littorine; Periwinkle *Littorina ziczac Gmelin *Littorina angulifera Lamarck Family Crepidulide.e Crepidula plana. Slipper Shell Family Naticidae *Polinices duplicata Say. Moon Snail; Shark Eye. Family Acmaeidae Acmaea scabra Gould. Limpets *Siphonaria lineolata Orbigny Family Solariidae Solarium granulatum Lamarck. Sun-Dial Family Neritidae *Nerita versicolor Gmelin Class Cephalopoda Order Dibranchiata Family Sepiolidae *Sthenotheuthis bartramii Lesueur. Squid Family Loliguidae Loligo brevipennis. Squid Order Decapoda Family Spirulidae *Spirula spirula Linne. Spiral Shell PHYLUM: ARTHROPODA Class Crustacea Order Cirripedia Family Lepadidae *Lepas anatifera Linnaeus. Goose Barnacles *Lepas pectinata Spengler. Family Balanidae *Balanus improvisus Darwin. Barnacles *Balanus eburneus Gould. Balanus balanoides. Balanus glandula Darwin. Order .Am.phipoda Family Gammaridae *Melita nitida Smith. Amphipod *Gammarus, sp. Gammarus Carinogammarus mucronatus. Scud Family Talitridae *Hyale hawaiensis {Dana). Amphipod orchestia agilis. Beach Flea; Beach Hopper Family .Amphithoidae *Ampithoe, sp. Amphipods Family Jassidae *Jassa marmorata Holmes. Amphipod Suborder Caprellidae *Caprella acutifrons, Latr. Skeleton Shrimp; Aunt Fanny Caprella, sp. Order Isopoda Superfamily Flabellifera *Sphaeroma quadridentatum Say. Isopod; Wood Borer· Sphaeroma destructor. *Ancinus, sp. Superfamily Oniscoidea *Ligyda exotica (Roux.) Isopod Order Stomatopoda Family Squillidae Squilla (Chloridella} empusa. Mud Shrimp Mantis Shrimp Order Decapoda Family Penaeidae *Penaeus aztecus Ives. ShrimpPenaeus setiferus. Common Shrimp Penaeus brasiliensis. Grooved Shrimp X.ylopenaeus kroyeri. Sea Bob Family Palaemonidae Palaemonetes vulgaris. Sargassum Shrimp; Grass Shrimp Tribe Anomura Family Paguridae Pagurus hirsutiusculus. Hairy Hermit Crab Pagurus pollicaris. Hermit Crab Clibinarius vittatus. Green Hermit Crab Holopagurus pilosus? Family Lithodidae Lopholithodes, sp. Box Crab Family Hippidae *Emerita benedicti· Schmitt. Burrowing Sand Crab Hippa talpoida Family Albuneidae Lepidopa myops Stimpson. Spiny Sand Crab Tribe Brachyura Subtribe Oxystomata Family Leucosiidae Randallia ornata (Randall). Purple Crab Subtribe Brachygnatha Superfamily Oxyrhyncha Family Inachida.e Oregonia gracilis Dana. Decorator Crab Loxorhynchus, sp. Spider Crab Superfamily Portunidae Portunis xantusii (Stimpson)? SE~~ing *Arenaeus cribrarius. Calico Crab Ovalipes ocellatus. Lady Crab Callinectes sapidus. Blue Crab Family Grapsidae Planes minutus Linnaeus. Pelagic Crab; "Shore Crab" Family Ocypodidae *Ocypode albicans Bose. Sand Crab *Uca pugilator (Bose.) Fiddler Crab; Uca minax. Sand Fiddler Uca, sp. Family Cancroidae Menippe mercenaria. Rock Crab Class Insecta Cicindela dorsalis. Tiger Beetle Staphylinid Scavenger Beetle Hydrometra?, sp. Salt-Vlater Strider Erax rufibarbus. Robber Fly Tabanus, sp. Botfly; Horsefly Tabanus costalis. Green-Eyed Fly Musca domestica Linn. Housefly Mormia, sp. Blaclr Blowfly PHYLUM: ECHINODERMATA Class Asteroidea Order Phanerozonia Family Astropectinidae *Astropecten antillensis Lutken. Sand Star; Astropecten, sp. Starfish Class Echinoidea Order Demosticha (Regularia) Family Arbacidae *Arbacia punctulata (Lamarck). Sea Urchin coeloplerus, sp. Order Clypeastroida Family Scutellidae *Encope michelini (L. Agassiz) •. Sand Dollar; Key-Hole Dollar PHYLUM CHORDATA SUBPHYLUM VERTEBRATA Class Elasmobranchii Order Batoidea Family Rajidae Raja erinaceae Mitchill. Common Skate Family Dasyatidae Urobatis sloani (Blainville). Round Sting Ray Class Pisces Order Isospondyli Family Megalopidae Tarpon atlanticus (Cuvier and Valenciennes). Tarpon Family Clupeidae Brevoortia patronus (Goode). Gulf Menhaden Order Colocephali Family Muraenidae Gymnothorax moringa (Cuvier). Spotted Moray Order Synentognathi Family Belonidae Strongylura marina (Walbaum). Needle Fish 120 Order Thoracostei Family Syngna.thidae Syngnathus floridae (Jordan and Gilbert) • Pipe Fish Hippocampus stylifer (Jordan and Gilbert). Sea Horse Order Percomorphi Family Mugilidae Mugil cephalus (Linnaeus). Mullet Family Cybiidae Scomberomorus maculatus (Mitchill). Mackerel Family Trichiuridae Trichiurus lepturus (Linnaeus). Ribbon Fish Family Carangidae Vomer setapinnis (Mitchill). Moon Fish Selene vomer. .. Lookdown Trachinotus carolinus (Linnaeus). Pompano Family Sparidae Arohosargus probatooephalus (Walbaum). Sheepshead Calamus arctifrons (Goode and Bean). Porgy Family Sciaenidae (Linnaeus) Pogonias cromis (Linnaeus). Drum Soiaenops ocellatus (Linnaeus). Redfish Family Ephippidae Chaetodipterus faber (Broussonet). Angel Fish Chaetodon ocellatus Bloch. Butterfly Fish Order Cataphracti Family Triglidae Prionotus pectoralis (Nichols and Breder). Sea Robin. Order Plectognathi Family Balistidae Balistes capriscus Gm~lin. Trigger Fish Family Ostraciidae Lactophrys tricor.nis {Linnaeus). Cow Fish Family Diodontidae Chilomycterus schoepfin (Walbaum). Spiny Boxfish Family Tetraodontidae Spheroides spengleri {Bloch). Swellfish; Blow Fish Family Blenniidae Rupiscartes atlanticus (Cuvier and Valenciennes). Rock Skipper Order Pediculati Family Antennaridae Histrio histrio {Linnaeus). Sargassum Fish Family Ogcocephalidae Ogcocephalus vespertilio (Linnaeus). Bat Fish Family Pleuronectidae Paralichthys lethostigmus Jordan and Gilbert. Fluke Paralichthys albiguttus Jordan and Gilbert. Gulf ]'luke Family Soleidae Achirus lineatus (Linnaeus). Striped Sole Class Aves Hydranassa tricolor. Louisiana Heron Ardea herodias. Great Blue Heron Egretta thula. Snowy Egret 122 Catoptrophorus semipalmatus. Willet Nurnenius longirostris VVils. Long-BillOO. curlew Larus atricilla. Laughing Gull Sterna hirundo. Common Tern Pelecanus 9ccidentalis. Brovm Pelican PLANT KINGDOM PHYLUM THALLOPHYTA Sargassum f luitans Borg. Gulfweed Sargassum natans (L.) Meyen. Gulfweed" .Ulva lactuca L. Alga; Sea Lettuce Cladophora fascicularis (Mertens) Kutz. AlgaEnteromorpha lingulata J. Ag. Alga Padina pavoni J. Ag. Alga PHYLUM SPERM.ATOPHYTA Sporobolus virginicus. Rush Grass Zostera marina. Eel Grass Entada gigas. Large Sea Bean Mucuna sloanei. Small Sea Bean. VITA This digitized document does not include the vita page from the original.