EFFECT OF FRESHWATER INFLOW ON MACROBENTHOS PRODUCTIVITY IN MINOR BAY AND RIVER-DOMINATED ESTUARIES - FYOl Paul A. Montagna, Principal Investigator TWDB Contract No. 2001-483-362 Technical Report Number TR/01-002 December 2001 I I I I 1 I , I I ~1 I I I I I I I I FINAL REPORT EFFECT OF FRESHWATER INFLOW ON MACROBENTHOS PRODUCTIVITY IN MINOR BAY AND RIVER-DOMINATED ESTUARIES FYOl by Paul A. Montagna, Principal Investigator from University of Texas at Austin Marine Science Institute 750 Channelview Drive Port Aransas, Texas 78373 to Texas Water Development Board P.O. Box 13231, Capital Station 1700 N. Congress Ave., Rm. 462 Austin, TX 78711-3231 Interagency Cooperative Contract TWDB Contract No. 2001-483-362 The University of Texas Marine Science Institute Technical Report Number TR/O1-002 October 2001 I I TABLE OF CONTENTS I LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii I PREFACE ...... . .. . . .. ................ .. . . ................................. iv I ACKNOWLEDGMENTS . .. .. . . . .................................... . .... . .. . .. v I INTRODUCTION ... .. .. . ...................................... .... ........... 1 I I METHODS ..... ; .......... . .... . ............................................ 2 Study Design and Area ....... . ............................................ 2 Hydrographic Measurements ............................................... 4 Chlorophyll and Nutrient Measurements ...................................... 5 Geological Measurements ................................................. 5 Biological Measurements .................................................. 5 Sediment Nitrogen Measurements . ....................................... . .. 6 RESULTS .... . .................................................... ... .. .. ... 7 Brazos River, Rio Grande, and South Bay .............................. . .... . . 7 Macrofauna in East Matagorda 'Bay ......................................... 10 Sediment Nitrogen in East Matagorda Bay ...................... . . . . . . ... .... 20 DISCUSSION ................ . .............................................. 27 Benthos in East Matagorda Bay ............................................ 27 Nitrogen Losses in East Matagorda Bay ..................................... 30 REFERENCES .... ........................................................... 31 I DATA APPENDICES .......... . .............................................. 33 Hydrography . .. . . . . . .. . ................................................ 33 Nutrients .. .. . .. . . . . ... . ............................................ ... 35 I Macrofaunal Abundance and Biomass ................................ . ... . . 37 Macrofaunal Community Structure ......... .. ............. . ... .. ....... . ... 43 I TWDB REVIEW .. . .. . . . ...... ... ........ . ....... . . . ................. . ..... .. 60 I I I I I I LIST OF FIGURES I Figure 1. Sampling locations within East Matagorda Bay, Texas . .. .. ................... 4 I Figure 2. Salinity in the Brazos River and Rio Grande ..... . .. . . . ...................... 8 Figure 3. Macrofauna biomass in the Brazos River and Rio Grande ................ . . .... 9 I Figure 4. Salinity and temperature at stations in East Matagorda Bay ........ . ... . . . .. ... 11 Figure 5. Biomass and abundance of macrofauna at stations in East Matagorda Bay ... . .... 12 I Figure 6. Biotic and abiotic characteristics average over all stations East Matagorda Bay .... 13 Figure 7. Plot of species loadings from a principal components analysis of macrofauna species in I East Matagorda Bay ..................................................... 14 Figure 8. Plot of stations scores from a principal components analysis of macrofauna species in ii East Matagorda Bay ... . ... . .. . ... ... .. . .. .... . . . ... ..................... 15 Figure 9. Nitrogen content of East Matagorda Bay sediments .. . ........ . . . ... . . . ...... 21 I Figure 10. Carbon content of East Matagorda Bay sediments ...... ... ................. 22 :I Figure 11. Average nitrogen and carbon content in East Matagorda Bay sediments ......... 23 I Figure 12. Profile of nitrogen (o 15N) isotope values in East Matagorda Bay sediments ...... 24 Figure 13. Profile of carbon (0 13C) isotope values in East Matagorda Bay sediments ....... 25I Figure 14. Average of nitrogen ( o15N)and carbon ( o13C)isotope values in East Matagorda Bay sediments ................................ .. . ..... ..................... 26 Figure 15. Salinity and dissolved oxygen (DO) in East Matagorda Bay in April 2000 ..... . .. 29 I I I I I I I 11 I LIST OF TABLES I Table 1. Long-term schedule for sampling minor bay and river-dominated systems ...... .... 2 I Table 2. Locations are given in degrees and decimal seconds format. .. ........ . .......... 3 Table 3. Systematic list of species found in East Matagorda Bay during the study period ... .. 16 I Table 4. Species dominance in East Matagorda Bay ............. . ... . ......... . ... ... 19 Table 5. Hydrographic data ... . ......... . . ... .. .. .. .. ... .. ......... . . . ......... . 33 I Table 6. Nutrient and chlorophyll data .. ..... .. . : .·............ : .............. . . ... 35 Table 7. Taxa abundance and biomass data . .. .. . . ...... . ...... . . . ...... ... . ..... .. 37 I Table 8. Species abundance data ... .............. ... .. .... ... ... ....... . . . . . ... .. 43 I I I ~~· · 1 I I I I I I I I 111 I PREFACE I The current contract is the first of a planned five-year study with the goal to determine the I importance of freshwater inflow in maintaining benthic productivity in minor bays and river dominated systems. Minor bays are defined as those small bays that do not have direct I freshwater inflow via a major river, but do have inflow from runoff or other indirect sources. Only a few rivers in Texas flow directly into the Gulf of Mexico, and these are also part of the I subject study. The current project follows successful completion of a long-term study of large, or major open bays in Texas. I The focus of this final report is on East Matagorda Bay. Biological data is added to a II previous sediment study on nitrogen losses to compile a complete view of that system. Sampling was also begun for a long-term study of two river-dominated systems, the Rio Grande and Brazos I River. The current report goes into lesser detail for this data as it will be subject to a fuller treatment in future. I ­ I 10 ····· ··· ·· ········· ·· ···· ···O I 0 Oct-2000 Jan-2001 Apr-2001 Jul-2001 Oct-2001 Date Figure 2. Salinity in the Brazos River and Rio Grande. Average over all stations at all sampling periods. I I I I I I I 8 I I I 6 0. I Brazos River ·· ·O ·· --Rio Grande 5 ·o I .0 .--.. 4 I <)! E CJ) ..__... 0 I (/) 3 (/) co E .Q I en 2 I 1 I 2001 2002 Year I Figure 3. Macrofauna biomass in the Brazos River and Rio Grande. Average over all stations at all sampling periods. I I I I I I 9 I I Macrofauna in East Matagorda Bay I Salinity was consistently lowest at station F, and highest at station B through out the entire sampling period (Figure 4). Stations B and C were slightly hypersaline in October 2000, indicating very little inflow from the Colorado River. The salinity pattern indicates that most I freshwater inflow is coming from the northeastern part of the bay. Temperature was the same at I all stations and followed a typical seasonal trend with lowest temperatures in winter. Macrofauna biomass generally increased from the northeastern part of the bay to the southwestern part of the bay (Figure 5). The only exception was in April 2001, when biomass at I stations Band C were the same. Abundance also generally increased from the northeastern part of the bay to the southwestern part of the bay . Station F always had the lo_west biomass and abundance. Biomass and abundance average over the whole bay followed the same temporal trend, with highest values in January 2001 (Figure 6). The highest organismal response correlated with I I the highest dissolved oxygen levels (near 8.5 mg 1-1), brackish salinities (near 20 ppt), and lowest temperatures (near 10 °C). Temperature and dissolved oxygen appeared to be more important than salinity when correlated to macrofauna biomass and abundance. A total of 52 species was found in East Matagorda Bay (Table 3). Polychaetes dominated the species list (29 species in all), followed by one-third as many Crustacea (10 species) and I Mollusca (9 species). The dominant species was Mediomastus ambiseta, a deposit-feeding polychaete (Table 4). Except for the clam Mulinia lateralis, the 10 most dominant species were all polychaetes. I The dominant species comprised 49% of the fauna overall. The eight most dominant species combined for a total of 82.93 of the individuals found. The remaining 44 species were relatively rare, comprising less than 2% of the individuals found. I A principal components (PC) analysis was performed on the eight most dominant species I (Figure 7). Five species loaded very strongly on the first PC axis (PCl): Lumbrineris parvapedata, Cirrophorus lyra, Mediomastus ambiseta, Aricidea catharinae, and Branchioasychis americana. Two species loaded strongly negative on PCl: Streblospio I benedicti, Cossura delta. The inverse loading on PCl indicates that those two species groups tend to not co-occur. Only one species, Mulinia lateralis, loaded on the second PC axis (PC2), I indicating this species does not tend to co-occur with any species on the PCl axis. The PC species loadings allow for interpretation of the PC scores for stations and sampling dates (Figure 8). Station F was the most distinct station, not sharing PCl space with I either of stations B and C, which had a great deal of overlap. This indicates that the community in station F, the most northeastern station was distinct from the stations in the middle (C) and southwestern (B) parts of the bay. Station F was dominated by S. benedicti and C. delta (Table 4, Figure 8). Mulinia lateralis occurred primarily in station B, and was most dominant in October 2000 and January 2001. Temporal succession appeared to have occurred. The communities in I October 2000 and April 2001 were very similar, but distinct from the July 2001 community. The highest diversity occurred in January 2001, which encompassed the entire species loading space. I I I 10 East Matagorda Bay 45 I 40 I 35 - Q. I ­ Q. 30 .__, I >­ ;t::: c 25 co (/) I 20 I 15 I 10 I 35 :I 30 •. I - 25 0 0.__, Q) ..... ::::I -co 20 I ..... Q) I E Q. Q) I-15 I 10 I 5 I Station F ~ a ,.,., ,.,., ---"' \ \ ....... \ \ \ \ \ \ \ \ \ ......... ........ ........ ........ -.....4 / APR2000 OCT2000 JAN2001 APR2001 JUL2001 Station F ~ APR2000 OCT2000 JAN2001 APR2001 JUL2001 Date I Figure 4. Salinity and temperature at stations in East Matagorda Bay. I 11 30 25 ....-. C)I 20 E O> ..__. (/) (/) 15 ro E 0 10 ~ en I 5 I 0 I 28000 26000 24000 22000 ....-. I C)I E 20000 c ..__. Q) 18000 I (.) c ro 16000 "'O c I :::l 14000 ..0 . 15 c ell Cl) 10 5 -e-Abundance -e-Biomass APR2000 OCT2000 JAN2001 APR2001 JUL2001 0 0 .. 0 ·o APR2000 OCT2000 JAN2001 APR2001 JUL2001 16 15 14 13 12 11 10 9 8 9.0 8.5 8.0 7.5 7.0 6.5 6.0 'l'­ E ~ (/) (/) ro E 0 ffi - en E - c Q) en >. x 0 "O Q) > 0 (/) (/) 0 Figure 6. Biotic and abiotic characteristics average over all stations East Matagorda Bay. I I 13 0 1 a.. I !I i I I -1.0 -0.5 0.0 0.5 1.0 I PC2 I Figure 7. Plot of species loadings from a principal components analysis of macrofauna species in I East Matagorda Bay. Abbreviations: Ma = Mediomastus ambiseta, CI = Cirrophorus lyra, Ac = Aricidea catharinae, Ml= Mulinia lateralis, Lp = Lumbrineris parvapedata, Sb= Streblospio benedicti, Cd= Cossura delta, and Ba= Branchioasychis americana. I I I 14 I I 2 I 1 I I ~ 0 0 0... I I -1 I -2 -2 -1 0 1 2 I PC2 2 I '' ' I 1 I 0 0 0... ,I ~ I -1 I I -2 -2 -1 0 2 I PC2 I Figure 8. Plot of stations scores from a principal components analysis of macrofauna species in East Matagorda Bay. I 15 I I Table 3. Systematic list of species found in East Matagorda Bay during the study period. Average abundance (n m-2) over all samples and sampling dates (October 2000 through July I 2001). Taxonomic name Abundance I I I I I I I ·,• ·,.1 I I I I ,I II i ;1 i ' !I Cnidaria Anthozoa Anthozoa (unidentified) Platyhelminthes Turbe Ilaria Turbellaria (unidentified) Rynchocoela Rhynchocoela (unidentified) Phoronida Phoronis architecta Mollusca Gastropoda Cuvier,1797 Acteocinidae Acteocina canaliculata Ctenobranchia Schweigger, 1820 Vitrinellidae Vitrinellidae (unidentified) Caecidae Gray, 1850 Caecum johnsoni Nassariidae Nassarius acutus Eritomotaeniata Cossman, 1896 Pyramidellidae Pyrgiscus sp. Pelecypoda Hippuritoidea Newell, 1965 Kelliidae Forbes & Hanley,1848 Aligena texasiana Leptonidae Mysella planulata Mactridae Mulinia lateralis Pholadomyoidea Newell, 1965 Pandoridae Pandora trilineata Annelida Polychaeta Polynoidae Malmgreniella taylori Phyllodocidae Paranaitis speciosa Pilargiidae 16 16 55 173 95 32 8 55 16 55 126 87 741 8 8 8 I I Pilargis berkelyae 8 Ancistrosyllis sp. 16I Hesionidae I Gyptis vittata 228 Nereidae Ceratonereis irritabilis 8 I Nereidae (unidentified) 8 Glyceridae I Glycera americana 32 Goniadidae Glycinde solitaria 95 I Lumbrineridae Lumbrineris parvapedata 559 Arabellidae Drilonereis magna 8 Spionidae I Paraprionospio pinnata 236 I Streblospio benedicti 496 Polydora caulleryi 158 Chaetopteridae Spiochaetopterus costarum 32 CirratulidaeI Tharyx setigera 32 Cossuridae Cossura delta 410 ~1 I -Drbiniidae Haploscoloplos fragilis 16 Paraonidae I Cirrophorus Lyra 1536 Aricidea catharinae 827 Capitellidae I Mediomastus ambiseta 7217 Maldanidae Branchioasychis americana 347 Clymenella torquata 126 Euclymene sp. B 24I Axiothells sp. A 134 Ampharetidae Melinna maculata 71I Sabellidae Megalomma bioculatum 16 Serpulidae I Eupomatus protulicola 142 I Oligochaeta Oligochaetes (unidentified) 16 Crustacea I 17 I I Copepoda CyclopoidaI Cyclopidae Hemicyclops sp. LichomolgidaeI Cyclopoid copepod (commensal) Malacostraca ReptantiaI Pinnotheridae I Pinnixa sp. Cumacea Oxyurostylis sp. I Leucon sp. Amphipoda Ampeliscidae Ampelisca abdita I Corophiidae I Corophium sp. Microprotopus sp. Liljeborgiidae Listriella barnardi Echinodermata I Ophiuroidea Ophiuroidea (unidentified) 16 24 8 8 47 32 8 8 8 189 "I I II I I I I I I I l8 Table 4. Species dominance in East Matagorda Bay. Mean abundance (n m-2) and per cent com.eosition of s.eecies over all sam.eles. I S.eecies B c F Mean PCT Mediomastus ambiseta 8,320 8,249 5,082 7,217 49.33 Cirrophorus Lyra 2,695 1,844 71 1,536 10.50 I Aricidea catharinae 473 1,300 709 827 5.66 Mulinia lateralis 1,371 591 260 741 5.06 Lumbrineris parvapedata 898 756 24 559 3.82I Streblospio benedicti 0 189 1,300 496 3.39 Cossura delta 284 95 851 410 2.80 Branchioasychis americana 165 804 71 347 2.37I Paraprionospio pinnata 95 378 236 236 1.62 I Gyptis vittata 355 331 0 228 1.56 Ophiuroidea (unidentified) 331 189 47 189 1.29 Rhynchocoela (unidentified) 95 260 165 173 1.18 I I Polydora caulleryi 189 95 189 158 1.08 Eupomatus protulicola 0 0 425 142 0.97 Axiothells sp. A 95 213 95 134 0.92 Aligena texasiana 355 0 24 126 0.86 Clymenella torquata 236 0 142 126 0.86 I Glycinde solitaria 118 71 95 95 0.65 Phoronis architecta 165 118 0 95 0.65 Mysella planulata 189 24 47 87 0.59 Melinna maculata 47 95 71 71 0.48 Caecum johnsoni 165 0 0 55 0.38 I Turbellaria (unidentified) 118 0 47 55 0.38 ,1 Pyrgiscus sp. 71 95 0 55 0.38 Leucon sp. 47 95 0 47 0.32 Spiochaetopterus costarum 95 0 0 32 0.22 Tharyx setigera 47 0 47 32 0.22 Acteocina canaliculata 0 95 0 32 0.22 I Glycera americana 0 95 0 32 0.22 I Ampelisca abdita 0 95 0 32 0.22 Cyclopoid copepod (commensal) 24 47 0 24 0.16 Euclymene sp. B 0 71 0 24 0.16 I I Hemicyclops sp. 47 0 0 16 0.11 Nassarius acutus 0 24 24 16 0.11 Anthozoa (unidentified) 0 0 47 16 0.11 Ancistrosyllis sp. 0 0 47 16 0.11 Haploscoloplos fragilis 0 0 47 16 0.11 I Megalomma bioculatum 0 0 47 16 0.11 Oligochaetes (unidentified) 0 0 47 16 0.11 Pandora trilineata 24 0 0 8 0.05 Malmgreniella taylori 24 0 0 8 0.05 Nereidae (unidentified) 24 0 0 8 0.05 I Oxyurostylis sp. 24 0 0 8 0.05 I 19 Microprotopus sp. 24 0 0 8 0.05 Paranaitis speciosa 0 24 0 8 0.05 I Pilargis berkelyae 0 24 0 8 0.05 Ceratonereis irritabilis 0 24 0 8 0.05 Pinnixa sp. 0 24 0 8 0.05I Vitrinellidae (unidentified) 0 0 24 8 0.05 Drilonereis magna 0 0 24 8 0.05 Corophium sp. 0 0 24 8 0.05I Listriella barnardi 0 0 24 8 0.05 Total 17,207 16,309 10,353 14,629 100.00 I I Sediment Nitrogen in East Matagorda Bay The highest concentrations of nitrogen (Figure 9) and carbon (Figure 10) in sediment appear to be at station A, which is the station nearest the Colorado River. On average, there is a strong decrease in carbon and nitrogen .values in the top 20 cm of sediment, and then values are relatively constant to 100 cm depth (Fig. 11). Nitrogen content in East Matagorda Bay sediment is about 0.07 % at the surface and declining to 0.05 to 0.04 % in the subsurface layer. I East Matagorda Bay had lowest nitrogen stable isotope ( o15N) values in station A nearest the Colorado River (Fig. 12) and highest carbon stable istope (o 13C) isotope values (Fig. 13) nearest the river in the top 20 cm of sediment. On average, the vertical profile of nitrogen values declined 2 parts per thousand (%0) indicating a change through the sediment profile (Fig. 14). On average, the vertical profile of carbon values varied 2 %0, decreasing mostly in the top 3 cm of sediment then increasing gradually to surface values. I I I I I I I 20 I East Matagorda Bay I I 0 V--.... . ··• •> I I ,-. 5 ....... 0... 0... 7.6 c a.> ..._.. C> >. I >. x ."!::::: 0 c 1:J 7.4 a.> ~ > (J) 0 I en en 0 7.2 I 7.0 I 6.8 A B E F \'I I Figure 15. Salinity and dissolved oxygen (DO) in East Matagorda Bay in April 2000. I I I I I I 1 29 I Nitrogen Losses in East Matagorda Bay I A great deal of nitrogen enters bays via river inflow. If this nitrogen is buried, then we would expect higher nitrogen values in sediments at the head of estuaries. This is because rivers empty into the secondary bay, and more nitrogen should be trapped in the upper reaches of the I bay. The trends in all Texas estuaries confirm this hypothesis (Montagna 1997). East Matagorda Bay has little or no river influence. Although recent salinity data (2000 -2001) indicates inflow is predominantly from Caney Creek, the elemental sediment composition indicates that I historically, overflow from the Colorado River was more important because both nitrogen I (Figure 9) and carbon (Figure 10) appear to have highest concentrations in sediments in at station A, nearest the Colorado River. It is likely that the sediments are influences by large floods, where overbanking of the Colorado could have an enormous influence. I Ifnitrogen is utilized, or transformed in the biologically active labile zone, then there should be higher values in upper layers of sediment and lower values at lower layers in the refractory zone. This hypothesis is confirmed by the trends seen in the estuary-wide average nitrogen content. On average, there is a strong decrease in carbon and nitrogen values in the top I 20 cm of sediment, and then values are relatively constant to 100 cm depth (Fig. 11). Thus, the labile zone appears to be limited to between 0 and 20 cm in East Matagorda Bay as it is in most Texas estuaries (Montagna,1997). Nitrogen content in most Texas estuarine sediment is 0.08 to I 0.15 percent(%) at the surface, and declines to 0.04 to 0.08 %. East Matagorda Bay sediment is similar with about 0.07 % at the surface and declining to 0.05 to 0.04 %. Man can influence another key component that affects nitrogen loss. In general, it is I thought that the sedimentation rate in Texas estuaries is about 1 cm per 100 years (Behrens, 1980). However, recent water projects, particularly dams, have probably decreased this rate. An average nitrogen background level, i.e., the average content at about 40 cm is about 0.05 %. The average surface nitrogen content is about 0.1 %, so the change between the labile and refractory zone is a factor of 2. This implies that half of the nitrogen arriving at the sediment surface is lost I to the system via burial. The change in stable isotope values at the surface verifies that the biogenic labile zone, which is dominated by fresh plant detritus, is limited to the top 20 cm. East Matagorda Bay had lowest nitrogen (o 15N) values in station A nearest the Colorado River (Fig. 12) and highest I I carbon (o 13C) isotope values (Fig. 13) nearest the river in the top 20 cm of sediment. The differences indicate the importance of primary production in producing depositional particulates in the bay. On average, the vertical profile of nitrogen values declined 2 parts per thousand (%0) indicating a change through the sediment (Fig. 14). On average, the vertical profile of carbon values varied 2 %0, decreasing mostly in the top 3 cm of sediment then increasing gradually to I surface values. These trends occur because the surface is biologically active. I I I I 30 I REFERENCES Behrens, E.W. 1980. On sedimentation rates and porosity. Marine Geology Letters, 35:Mll­ I Ml6. Folk, R. L. 1964. Petrology of sedimentary rocks. Hemphill's Press. Austin, TX. 155 pp. I Jones, R.S., J.J. Cullen, R.G. Lane, W. Yoon, R.A. Rosson, R.D. Kalke, S.A. Holt and C.R. I Arnold. 1986. Studies of freshwater inflow effects on the Lavaca River Delta and Lavaca Bay, TX. Report to the Texas Water Development Board. The University of Texas Marine Science Institute, Port Aransas, TX. 423 pp. I Kalke, RD. and Montagna, P.A. 1991. The effect of freshwater inflow on macrobenthos in the Lavaca River Delta and Upper Lavaca Bay, Texas. Contributions in Marine Science, I 32:49-71. Montagna, P.A. 1989. Nitrogen Process Studies (NIPS): the effect of freshwater inflow on benthos communities and dynamics. Technical Report No. TR/89-011, Marine Science I Institute, The University of Texas, Port Aransas, TX, 370 pp. Montagna, P.A. 1991. Predicting long-term effects of freshwater inflow on macrobenthos in the Lavaca-Colorado and Guadalupe Estuaries. Year 2. Technical Report No. TR/91-004, Marine Science Institute, The University of Texas, Port Aransas, TX, 78 pp. Montagna, P.A. 1997. Effect of freshwater inflow on macrobenthos productivity and nitrogen I losses in Texas estuaries. Final report to Texas Water Development Board, Contract No. 97-483-199, University of Texas Marine Science Institute Technical Report Number TR/97-02, Port Aransas, Texas. 157 pp. I Montagna, P.A. 1998. Effect of freshwater inflow on macrobenthos productivity and nitrogen losses in Texas estuaries. Final report to Texas Water Development Board, Contract No. 98-483-233, University of Texas Marine Science Institute Technical Report Number TR/98-03, Port Aransas, Texas. 62 pp. I Montagna, P.A. 1999. Predicting long-term effects of freshwater inflow on macrobenthos and nitrogen losses in the Lavaca-Colorado and Guadalupe Estuaries. Final Report to Texas Water Development Board. Technical Report No. TR/99-001, Marine Science Institute, I The University of Texas, Port Aransas, TX, 68 pp. Montagna, P.A. 2000. Effect of freshwater inflow on macrobenthos productivity and nitrogen losses in Texas estuaries. Final report to Texas Water Development Board, Contract No. 2000-483-323, University of Texas Marine Science Institute Technical Report Number I TR/00-03, Port Aransas, Texas. 78 pp. I Montagna, P.A. and R.D. Kalke. 1992. The Effect of Freshwater Inflow on Meiofaunal and Macrofaunal'Populations in the Guadalupe and Nueces Estuaries, Texas. Estuaries, 15:307-326. Montagna, P.A. and R.D. Kalke. 1995. Ecology of infauna! Mollusca in south Texas estuaries. American Malacological Bulletin 11:163-175. I Montagna, P.A., and Li, J. 1996. Modeling and monitoring long-term change in macrobenthos in Texas estuaries. Final Report to the Texas Water Devlopment Board. University of Texas at Austin, Marine Science Institute, Technical Report No. TR/96-001, Port I Aransas, Texas, 149 pp. Montagna, P.A. and W.B. Yoon. 1991. The effect of freshwater inflow on meiofaunal consumption of sediment bacteria and microphytobenthos in San Antonio Bay, Texas I USA. Estuarine and Coastal Shelf Science, 33:529-547. I 31 I SAS Institute, Incorporated. 1985. SAS/STAT Guide for Personal Computers, Version 6 Edition. Cary, NC:SAS Institute Inc., 378 pp. I Texas Department of Water Resources. 1980a. Lavaca-Tres Palacios Estuary: A study of influence of freshwater inflows. Publication LP-106. Texas Department of Water Resources, Austin, Texas. 325 p.I Texas Department of Water Resources. 1980b. Guadalupe Estuary: A study of influence of I freshwater inflows. Texas Department of Water Resources, Austin, Texas. Publication LP-107. 321 p. Welschmeyer, N. A. 1994. Fluorometric analysis of chlorophyll a in the presence of chlorophyll band pheopigments. Limnol. Oceanogr., 39:1985-1992. I I I I I ;I I I I I I I I I 32 I DATA APPENDICES I Hydrography Table 5. Hydrographic data. Abbreviations: Bay (East Matagorda Bay= EM, Brazos River=I BR, Rio Grande= RG, South Bay= SB), STA= station, z =depth (m), SAL(R) =salinity by refractometer (ppt), SAL(M) =salinity by meter (psu), COND =conductivity (uS/cm), TEMP= tem~erature (°C), DO = dissolved oxygen (mg/l). I Bay Date STA z SAL(R) SAL(M) COND TEMP EH DO EM 19APR2000 A 0.00 32 33.9 51.66 25.83 7.98 7.39 EM 19APR2000 A 1.20 33.9 51.63 25.84 7.98 6.62 I EM 19APR2000 B 0.00 32 34.2 52.00 26.02 7.95 7.52 I EM 19APR2000 B 1.20 34.2 52.00 25.96 7.94 6.65 EM 19APR2000 c 0.00 30 31.8 48.83 26.26 8.01 7.77 EM 19APR2000 c 1.30 31.9 48.85 26.22 8.00 6.83 EM 19APR2000 D 0.00 29 31.3 48.04 26.80 8.13 8.08 EM 19APR2000 D 1.10 31.3 48.08 26.71 8.14 6.67 EM 19APR2000 E 0.00 28 30.0 46.40 27.32 8.20 8.55I EM 19APR2000 E 0.70 30.0 46.38 27.35 8.21 7.52 I I EM 19APR2000 F 0.00 28 29.5 45.75 28.54 8.19 9.38 EM 19APR2000 F 0.70 29.5 45.69 28.51 8.19 6.57 EM 190CT2000 B 0.00 36 39.6 59.14 24.23 7.95 6.67 EM 190 CT2000 B 1.20 39.6 59.14 24.19 7.93 6.43 EM 190 CT2000 c 0.00 35 37.4 56.26 23 .85 8.09 7.35 EM 190 CT2000 c 1.40 39.3 58.73 23.02 8.00 6.56 EM 190CT2000 F 0.00 30 32.6 49.75 23 .24 8.14 8.10 I EM 190CT2000 F 0.80 32.7 49.85 23.25 8.17 6.53 EM 09JAN2001 B 0.00 22 23.3 36.97 10.60 8.30 8.16 '~I EM 09JAN2001 B 1.00 24.0 37.75 10.84 8.31 8.54 EM 09JAN2001 c 0.00 20 21.9 34.89 11.24 8.37 8.31 EM 09JAN2001 c 1.00 22.9 36.25 11.37 8.34 7.63 EM 09JAN2001 F 0.00 15 17.0 27.71 11.78 8.54 9.76 EM 09JAN2001 F 0.47 17.1 27.81 11.77 8.53 9.10 EM 09APR2001 B 0.00 16 17.8 28.89 25.58 7.90 7.71 EM 09APR2001 B 1.39 17.8 28.89 25.27 7.87 7.08 I EM 09APR2001 c 0.00 12 13.7 22.73 25.55 8.05 7.78 I EM 09APR2001 c 1.49 14.4 23.86 24.61 7.95 6.26 EM 09APR2001 F 0.00 11 13.3 22.08 26.20 7.93 7.88 EM 09APR2001 F 0.83 14.l 23 .32 24.91 7.87 6.76 EM 11JUL2001 B 0.00 20 23.3 37.00 30.21 8.06 6.52 EM 11JUL2001 B 1.00 23 .3 37.00 30.04 8.03 6.24 EM 11JUL2001 c 0.00 20 22.l 35.30 30.44 8.15 6.62I EM 11JUL2001 c 1.00 22.l 36.31 30.21 8.12 6.34 I EM 11JUL2001 F 0.00 20 23.l 36.82 31.05 8.10 6.87 EM 11JUL2001 F 0.50 23.l 36.82 31.01 8.09 6.76 BR 180CT2000 A 0.00 24.8 39.04 26.50 8.09 10.00 BR 180CT2000 A 3.30 31.7 48.71 26.71 7.59 5.61 BR 180CT2000 B 0.00 22 26.0 40.79 26.68 8.04 9.43 BR 180CT2000 B 2.80 29.l 45.10 26.29 7.86 7.86I BR 180CT2000 c 0.00 25 28.4 43.97 25.42 8.04 7.64 I BR 180CT2000 c 3.00 29.2 45 .20 25.04 7.99 6.57 BR 10JAN2001 A 0.00 0 3.1 5.69 8.74 8.01 10.28 BR 10JAN2001 A 2.60 3.2 5.82 8.75 7.95 9.32 BR 10JAN2001 B 0.00 0 3.7 6.76 8.85 8.00 9.70 I 33 I I BR 10JAN2001 B 2.80 3.7 6.77 8.84 7.98 9.13 BR 10JAN2001 c 0.00 0 3.9 7.04 8.85 8.01 9.73 BR 10JAN2001 c 2.40 3.9 7.13 8.84 7.99 8.97 BR 10APR2001 A 0.00 0 1.6 3.10 22.60 7.95 7.72 BR 10APR2001 A 2.50 1.7 3.26 22.60 7.92 7.69 BR 10APR2001 B 0.00 0 2.1 3.95 22.63 7.92 7.93I BR 10APR2001 B 1.60 2.1 3.96 22.57 7.91 7.90 I BR 10APR2001 c 0.00 0 2.2 4.22 22.76 7.95 8.06 BR 10APR2001 c 2.60 2.4 4.60 22.75 7.91 7.94 BR llJUL2001 A 0.00 1 3.1 5.86 32.47 7.72 5.78 BR 11JUL2001 A 3.10 24.2 38.37 32.34 7.30 2.81 BR 11JUL2001 B 0.00 2 4.6 8.37 32.96 7.88 6.66 BR l 1JUL2001 B 1.90 7.4 14.41 32.43 7.74 5.60I BR 11JUL2001 c 0.00 5 6.7 11.82 32.87 7.88 6.53 I I BR 11JUL2001 c 1.60 19.6 32.70 31.30 7.80 5.76 RG 240CT2000 A 0.00 3 4.8 8.59 26.43 8.94 11.87 RG 240CT2000 A 0.38 4.8 8.58 26.46 8.93 11.34 RG 240CT2000 B 0.00 5.5 9.80 26.84 8.90 10.56 RG 240CT2000 B 0.28 5.5 9.89 26.74 8.90 9.79 RG 240CT2000 c 0.00 6 7.7 13.50 27.48 8.40 9.54 RG 240CT2000 c 0.32 7.8 13.50 27.48 8.38 8.77 I I RG 10JAN2001 A 0.20 4.5 15.48 8.45 10.23 RG 10JAN2001 A 0.80 4.5 15.46 8.57 9.65 RG 10JAN2001 B 0.20 5.0 15.19 8.20 9.65 RG 10JAN2001 B 0.75 5.0 15.14 8.38 9.55 RG 10JAN2001 c 0.50 8.6 18.13 8.75 9.70 RG 10JAN2001 c 0.64 8.6 18.13 8.80 8.40 RG 14APR2001 A 1.4 27.08 8.69 5.98 RG 14APR2001 .A 0.60 1.4 27.08 8.65 6.62 RG 14APR2001 B 1.5 26.63 8.64 6.41I RG 14APR-2001 B 0.60 1.5 26.66 8.60 6.55 I RG 14APR2001 c 2.3 26.19 8.42 4.82 RG 14APR2001 c 0.60 2.3 26.18 8.36 5.68 RG 07JUL2001 A 0.65 0.7 12.96 30.18 8.44 6.99 RG 07JUL2001 A 0.65 0.7 12.96 30.17 8.44 6.71 RG 07JUL2001 B 0.61 0.7 13.08 29.62 8.45 7.12 RG 07JUL2001 B 0.61 0.7 13.07 29.61 8.46 6.74I RG 07JUL2001 c 0.60 0.9 1.76 28.46 8.44 5.62 I RG 07JUL2001 c 0.60 0.9 1.76 28.42 8.41 5.02 SB 240CT2000 A 0.00 35 37.4 56.36 25.98 8.13 6.90 SB 240CT2000 A 0.98 40.0 59.61 26.45 8.14 3.24 SB 240CT2000 B 0.00 32 35.2 53.33 24.94 8.04 6.85 SB 240CT2000 B 0.80 35.2 53.33 24.95 8.04 4.99 I SB 10JAN2001 A 0.00 38.9 17.14 8.14 8.72 SB 10JAN2001 A 0.85 39.0 17.12 8.20 8.59 I I SB 10JAN2001 B 0.00 35.7 14.22 8.05 7.30 SB 10JAN2001 B 0.60 35.7 14.19 8.06 7.27 SB 14APR2001 A 0.00 37.4 27.90 7.89 7.12 SB 14APR2001 A 1.00 38.6 28.26 7.94 8.26 SB 14APR2001 B 0.00 35.7 23.83 7.96 6.81 SB 14APR2001 B 0.80 35.8 23.82 7.97 6.79 SB 07JUL2001 A 0.00 37.2 30.78 8.24 8.12 I SB 07JUL2001 A 0.50 37.3 31.12 8.29 7.82 SB 07JUL2001 B 0.00 37.2 29.50 8.16 7.52 SB 07II TI 200 I B a 70 37 2 29 52 8 I 8 7 so 1 34 I I I Nutrients I Table 6. Nutrient and chlorophyll data. Abbreviations: Bay (East Matagorda Bay = EM, Brazos River= BR, Rio Grande= RG, South Bay= SB), STA= station, N+N =nitrate plus nitrite, Chl I =chlorophyll a. Water depth is in m. Nutrient concentrations are in umol/l. Chlorophyll concentrations in ug/l. I I Ba~ Date STA Deeth PO! SIO! N+N NH~ Chi EM 190CT2000 B 0 1.668 49 0.000 1.937 EM 190CT2000 B 1.598 49 0.000 1.818 EM 190CT2000 c 1.746 42 0.000 1.914 EM 190CT2000 c 0 1.633 31 0.000 1.652 I EM 190CT2000 F 1.046 16 0.000 0.994 EM 190CT2000 F 0 1.132 15 0.160 1.129 EM 09JAN2001 B 0.680 73 5.490 2.25 1.730 EM 09JAN2001 B 0 0.370 82 5.020 2.56 2.680 I EM 09JAN2001 c 0.470 130 10.31 14.78 2.730 EM 09JAN2001 c 0 0.390 133 10.91 9.75 2.240 EM 09JAN2001 F 0.600 147 11.62 16.19 0.210 I EM 09JAN2001 F 0 0.760 147 12.51 15.60 0.610 EM 09APR2001 B 0.740 202 1.600 8.85 0.150 EM 09APR2001 B 0 0.520 183 0.810 7.93 1.570 EM 09APR2001 c 0.650 170 4.970 16.98 1.040 EM 09APR2001 c 0 0.600 172 6.120 15.03 0.850 EM 09APR2001 F 1.320 204 19.96 9.48 5.370 I EM 09APR2001 F 0 1.110 178 17.77 5.55 4.520 EM 11JUL2001 B 1.940 262 1.880 11.43 0.260 EM 11JUL2001 B 0 1.810 276 2.470 8.88 0.000 EM U_JUL2001 c 2.060 153 1.310 11.13 0.250 '::I EM 11JUL2001 c 0 1.860 157 1.730 8.70 1.180 EM 11JUL2001 F 1.720 199 1.720 18.23 0.000 EM 11JUL2001 F 0 1.480 198 1.560 16.18 0.000 I BR 180 CT2000 A 1.917 45 36.56 15.744 I I BR 180 CT2000 A 0 1.646 62 37.66 5.396 BR 180CT2000 B 2.164 45 35.90 . 15.063 BR 180 CT2000 B 0 0.688 32 30.79 3.668 BR 180CT2000 c 1.207 31 22.42 16.031 BR 180CT2000 c 0 1.310 42 26.15 15.880 BR 10JAN2001 A 2.030 284 29.57 10.26 7.390 BR 10JAN2001 A 0 1.740 237 32.58 3.24 6.760 I BR 10JAN2001 , B 2.81 BR 10JAN2001 B 0 1.660 287 25.49 5.71 6.990 BR 10JAN2001 c 1.740 286 37.24 6.90 6.960 BR 10JAN2001 c 0 1.490 307 21.53 3.53 6.560 I BR 10APR2001 A 1.200 318 51.31 5.58 3.890 BR 10APR2001 A 0 11.18 233 57.40 5.14 4.050 BR 10APR2001 B 1.260 324 56.89 3.62 4.810 BR 10APR2001 B 0 0.000 362 54.36 6.03 4.820 BR 10APR2001 c 1.550 349 59.46 5.45 4.970 I BR 10APR2001 c 0 1.330 250 59.46 4.52 4.510 I BR l IJUL2001 A 4.340 156 11.15 23.90 25.550 BR 11JUL2001 A 0 3.310 349 9.3 80 5.84 4.630 BR l 1JUL2001 B 3.150 330 4.180 7.20 2.090 BR l 1JUL2001 B 0 3.480 335 4.230 6.46 5.170 I 35 I I BR 11JUL2001 c 3.930 214 46.83 21.67 8.310 BR l 1JUL2001 c 0 3.490 350 66.65 7.94 5.100 BR 120CT2001 A BR 120CT2001 A 0 BR 120CT2001 B BR 120CT2001 B 0 I BR 120CT2001 c I BR 120CT2001 c 0 RG 240CT2000 A 4.504 145 0.000 58.88 0.802 RG 240CT2000 A 0 4.432 149 0.000 66.64 0.826 RG 240CT2000 B 6.558 156 0.000 33.19 0.817 RG 240CT2000 B 0 6.486 169 0.000 33.45 0.841 RG 240CT2000 c 6.651 181 0.000 17.17 0.960 RG 240CT2000 c 0 6.630 178 0.000 17.96 0.778 I RG 10JAN2001 A 9.240 198 37.48 55.96 0.480 RG 10JAN2001 A 0 8.820 I 188 37.24 50.11 0.700 RG 10JAN2001 B 6.860 178 22.37 38.15 1.060 RG 10JAN2001 B 0 6.480 183 23.58 37.65 1.030 RG 25JAN2001 c I 21.11 RG 25JAN2001 c 0 20.35 RG 14APR2001 A 36.76 RG 14APR2001 A 0 40.57 RG 14APR2001 B I 33.58 RG 14APR2001 B 0 37.26 RG 14APR2001 c 37.65 RG 14APR2001 c 0 I 37.01 RG 07JUL2001 A 14.73 RG 07JUL2001 A 0 13.56 RG 07JUL2001 B 17.32 RG 07JUL2001 B 0 17.25 •t ·>1 RG 07JUL2001 c 27.12 RG 07JUL2001 c 0 25.84 SB 240CT2000 A I 0.555 13 0.000 2.93 1.453 SB 240CT2000 A 0 0.433 6 0.000 1.08 0.668 SB 240CT2000 B 9 0.760 0.000 2.59 1.152 SB 240CT2000 B 0 0.631 I 7 0.000 2.63 1.033 SB 10JAN2001 A 0.140 6 1.940 2.35 0.190 SB 10JAN2001 A 0 0.140 8 2.260 1.59 0.460 SB 10JAN2001 B 26 0.280 1.860 4.20 0.650 SB 10JAN2001 B 0 0.240 I 31 1.910 3.12 0.670 SB 14APR2001 A 2.07 SB 14APR2001 A 0 1.40 SB 14APR2001' B 6.14 SB 14APR2001 B 0 I 8.62 SB 07JUL2001 A 4.90 SB 07JUL2001 A 0 1.69 SB 07JUL2001 B I 3.57 SB 07JUL2001 B 0 3.42 I I I 36 I I Macrofaunal Abundance and Biomass I Table 7. Taxa abundance and biomass data. Abbreviations: Bay (East Matagorda Bay= EM, Brazos River= BR, Rio Grande= RG, South Bay= SB), REP= replicate, n =number of individuals. Core area is 35.3 cm2, multiply by 283 to obtain nor mg per m2• I Bay Date Station REP Taxa n/core m&'._core EM 190CT2000 B Mollusca 6 19.51I EM 190CT2000 B Ophiuroidea 2 125.01 I EM 190CT2000 B 1 Polychaeta 34 3.91 EM 190CT2000 B 2 Mollusca 13 51 .23 EM 190CT2000 B 2 Ophiuroidea 1 0.29 EM 190CT2000 B 2 Polychaeta 44 7.10 EM 190CT2000 B 3 Crustacea 2 0.02 EM 190CT2000 B 3 Mollusca 10 20.27I EM 190CT2000 B 3 Other 3 0.56 EM 190CT2000 B 3 Ophiuroidea 1 10.01 EM 190CT2000 B 3 Polychaeta 33 10.17 ·1 EM 190CT2000 c Mollusca 1 0.07 I EM 190CT2000 c Ophiuroidea 1 7.48 EM 190CT2000 c 1 Polychaeta 19 5.01 EM 190CT2000 c 2 Mollusca 7 17.10 EM 190CT2000 c 2 Rhynchocoela 2 0.85 I EM 190CT2000 c 2 Other 1 2.28 EM 190CT2000 c 2 Polychaeta 48 11.89 EM 190CT2000 c 3 Crustacea 2 0.63 EM 190CT2000 c 3 Mollusca 2 13.04 EM 190CT2000 c 3 Ophiuroidea 1 0.03 EM 190CT2000 c 3 Polychaeta 26 7.59 :~1 EM 190-CT2000 F 1 Crustacea 1 0.03 EM 190CT2000 F 1 Mollusca 3 0.05 EM 190CT2000 F 1 Rhynchocoela 1 0.01I EM 190CT2000 F 1 Polychaeta 35 18.84 EM 190CT2000 F 2 Mollusca 0.06 EM 190CT2000 F 2 Rhynchocoela 3.50 EM 190CT2000 F 2 Other 0.04 EM 190CT2000 F 2 Ophiuroidea 1 4.82 ;.I EM 190CT2000 F 2 Polychaeta 30 3.11 EM 190CT2000 F 3 Mollusca 1 0.47I EM 190CT2000 F 3 Rhynchocoela 0.32 I EM 190CT2000 F 3 Ophiuroidea 1 0.08 EM 190CT2000 F 3 Polychaeta 29 6.36 EM 09JAN2001 B Mollusca 16 43.76 EM 09JAN2001 B Other 1 0.02 EM 09JAN2001 B Ophiuroidea 1 11.47 EM 09JAN2001 B Polychaeta 50 9.69 I EM 09JAN2001 B 2 Mollusca 7 26.29 I I EM 09JAN2001 B 2 Rhynchocoela 1 0.26 EM 09JAN2001 B 2 Other 0.35 EM 09JAN2001 B 2 Ophiuroidea 49.09 EM 09JAN2001 B 2 Polychaeta 48 6.27 EM 09JAN2001 B 3 Crustacea 2 0.04 EM 09JAN2001 B 3 Mollusca 10 38.85 EM 09JAN2001 B 3 Other 0.05 37 I I I I EM 09JAN2001 B 3 Ophiuroidea l 108.94 EM 09JAN2001 B 3 Polychaeta 116 9.72 EM 09JAN2001 c Crustacea l 0.05 EM 09JAN2001 c Ophiuroidea l 9.86 EM 09JAN2001 c Polychaeta 49 14.17 EM 09JAN2001 c 2 Mollusca 2 3.92 EM 09JAN2001 c 2 Rhynchocoela 2 4.61 I EM 09JAN2001 c 2 Other 0.10 EM 09JAN2001 c 2 Ophiuroidea 14.70 EM 09JAN2001 c 2 Polychaeta 105 34.44 I EM 09JAN2001 c 3 Rhynchocoela 1 0.10 EM 09JAN2001 c 3 Other 2 0.08 EM 09JAN2001 c 3 Ophiuroidea 2 67.09 EM 09JAN2001 c 3 Polychaeta 99 10.88 EM 09JAN2001 F Mollusca 1 0.45 EM 09JAN2001 F 1 Polychaeta 20 6.05 I EM 09JAN2001 F 2 Crustacea l 0.07 I EM 09JAN2001 F 2 Polychaeta 42 7.90 EM 09JAN2001 F 3 Polychaeta 36 3.63 EM 09APR2001 B Crustacea l 0.17 EM 09APR2001 B Mollusca 1 0.03 EM 09APR2001 B Other 2 0.38 EM 09APR2001 B Ophiuroidea 1 64.03I EM 09APR2001 B 1 Polychaeta 47 8.87 I EM 09APR2001 B 2 Mollusca 3 0.08 EM 09APR2001 B 2 Polychaeta 35 5.43 EM 09APR2001 B 3 Mollusca 4 0.19 EM 09APR2001 B 3 Rhynchocoela 1 1.08 EM 09APR2001 · B 3 Other 3 0.45 EM 09APR2001 B 3 Ophiuroidea 1 12.00 ·(1 I I EM 09APR2001 B 3 Polychaeta 67 14.32 EM 09APR2001 c Crustacea 2 0.02 EM 09APR2001 c Mollusca 5 0.93 EM 09APR2001 c Ophiuroidea l 18.95 EM 09APR2001 c 1 Polychaeta 55 22.07 EM 09APR2001 c 2 Crustacea 4 0.08 .EM 09APR2001 c 2 Mollusca 6 1.41 EM 09APR2001 c 2 Rhynchocoela 3 1.07 EM 09APR2001 c 2 Ophiuroidea l 5.64 EM 09APR2001 c 2 Polychaeta 89 37.78 I EM 09APR2001 c 3 Crustacea 1 0.03 I EM 09APR2001 c 3 Mollusca 13 4.22 EM 09APR2001 ' c 3 Other l 0.12 EM 09APR2001 c 3 Polychaeta 59 34.09 EM 09APR2001 F Other l 0.03 EM 09APR2001 F 1 Polychaeta 35 7.35 EM 09APR2001 F 2 Mollusca 2 0.02I EM 09APR2001 F 2 Rhynchocoela 1 5.62 I EM 09APR2001 F 2 Other 2 4.27 EM 09APR2001 F 2 Polychaeta 58 19.58 EM 09APR2001 F 3 Mollusca 5 4.29 EM 09APR2001 F 3 Rhynchocoela 2 0.20 EM 09APR2001 F 3 Polychaeta 39 4.62 EM l 1JUL2001 B Crustacea 0.01I EM 11JUL2001 B Mollusca 17 2.84 I 38 I I EM l 1JUL2001 B ' Rhynchocoela 0.65 EM l 1JUL2001 B Other 0.41 EM 11JUL2001 B Ophiuroidea 94.78 EM 11JUL2001 B l Polychaeta 74 16.41 EM 11JUL2001 B 2 Mollusca 4 0.65 EM 11JUL2001 B 2 Ophiuroidea 2 23.40I EM 11JUL2001 B 2 Polychaeta 53 14.32 I EM 11JUL2001 B 3 Crustacea 0.01 EM llJUL2001 B 3 Mollusca 0.26 EM llJUL2001 B 3 Rhynchocoela l 0.02 EM 11JUL2001 B 3 Ophiuroidea 2 27.86 EM llJUL2001 B 3 Polychaeta 48 9.32 EM 11JUL2001 c Crustacea 1 0.02I EM llJUL2001 c Rhynchocoela 0.39 I I EM llJUL2001 c 1 Polychaeta 13 8.76 EM 11JUL2001 c 2 Polychaeta 21 6.46 EM llJUL2001 c 3 Rhynchocoela 0.03 EM 11JUL2001 c 3 Ophiuroidea 24.00 EM llJUL2001 c 3 Polychaeta 42 26.92 EM 11JUL2001 F Mollusca 2 0.07 EM 11JUL2001 F Rhynchocoela l 0.37 I EM llJUL2001 F Polychaeta 20 4.39 EM llJUL2001 F 2 Polychaeta 36 4.20 EM llJUL2001 F 3 Polychaeta 28 2.97 I BR 180CT2000 A 1 Polychaeta 41 2.17 BR 180CT2000 A 2 Polychaeta 41 3.27 BR 180CT2000 A 3 Polychaeta 11 1.44 BR 180CT2000 B Polychaeta 16 6.55 BR 180CT2000 . B 2 Mollusca l 0.03;I BR 180 CT2000 B 2 Polychaeta 16 0.39 I BR 180CT2000 B 3 Polychaeta 14 0.41 BR 180CT2000 c Polychaeta 6 0.55 BR 180CT2000 c 2 Polychaeta 5 2.43 BR 180CT2000 c 3 Polychaeta 4 1.00 BR 10JAN2001 A l Polychaeta 13 3.50 BR 10JAN2001 A 2 Other 0.10 BR 10JAN2001 A 2 Polychaeta 10 2.50I BR 10JAN2001 A 3 Polychaeta 12 1.10 I I BR 10JAN2001 B 1 Polychaeta 19 1.40 BR 10JAN2001 B 2 Polychaeta 22 1.73 BR 10JAN2001 B 3 Polychaeta 36 2.00 BR 10JAN2001 c Rhynchocoela 0.07 BR 10JAN2001 c Polychaeta 14 3.35 BR 10JAN2001 c 2 Polychaeta 12 4.97 BR 10JAN2001 c 3 Polychaeta 12 2.03 BR 10APR2001 A Crustacea 0.03 BR 10APR2001 A Chironomid larvae 0.29 I BR 10APR2001 A Polychaeta 14 6.49 I BR 10APR2001 A 2 Chironomid larvae 1 O.Ql BR 10APR2001 A 2 Polychaeta 10 0.52 BR 10APR2001 A 3 Rhynchocoela 2 2.83 BR 10APR2001 A 3 Polychaeta 11 1.71 BR 10APR2001 B Chironomid larvae 2 0.02 BR 10APR2001 B I Polychaeta 28 6.39 I BR 10APR2001 B 2 Chironomid larvae 0.07 I 39 I I BR 10APR2001 B 2 Polychaeta 33 5.50 BR 10APR2001 B 3 Polychaeta 34 4.31 BR 10APR2001 c Polychaeta 12 13.89 BR 10APR2001 c 2 Polychaeta 7 2.73 BR 10APR2001 c 3 Polychaeta 33 10.81 BR l 1JUL2001 A 1 Polychaeta 5 0.34I BR 11JUL2001 A 2 Polychaeta 3 0.35 I I BR 11JUL2001 A 3 Polychaeta 3 0.67 BR 11JUL2001 B 1 Crustacea 1 0.03 BR l 1JUL2001 B 1 Rhynchocoela 4 0.18 BR l 1JUL2001 B 1 Polychaeta 20 2.13 BR 11JUL2001 B 2 Polychaeta 18 2.85 BR 11JUL2001 B 3 Crustacea 1 0.26 BR 11JUL2001 B 3 Polychaeta 11 2.29 I BR 11JUL2001 c 1 Polychaeta 30 1.74 BR 11JUL2001 c 2 Crustacea 1 0.27 BR 11JUL2001 c 2 Polychaeta 13 3.64 I BR 11JUL2001 c 3 Polychaeta 24 6.20 RG 240CT2000 A Chironomid larvae 3 0.30 RG 240CT2000 A Mollusca 5 19.26 RG 240CT2000 A Rhynchocoela 6 0.64 RG 240CT2000 A 1 Polychaeta 28 2.79 RG 240CT2000 A 2 Chironomid larvae 3 0.27I RG 240CT2000 A 2 Mollusca 5 0.67 I RG 240CT2000 A 2 Rhynchocoela 6 0.71 RG 240CT2000 A 2 Polychaeta 50 4.02 RG 240CT2000 A 3 Chironomid larvae 2 0.17 RG 240CT2000 A 3 Mollusca 5 0.28 'I RG 240CT2000 A 3 Rhynchocoela 7 0.43 RG 240CT2000 A 3 Polychaeta 50 4.18 RG 240CT2000 B Mollusca 3 49.50 I I RG 240 CT2000 B Rhynchocoela 1 0.04 RG 240CT2000 B 1 Polychaeta 16 1.49 RG 240CT2000 B 2 Chironomid larvae 4 0.18 RG 240CT2000 B 2 Mollusca 13.46 RG 240 CT2000 B 2 Rhynchocoela 1 0.06 RG 240CT2000 B 2 Polychaeta 27 3.10 RG 240CT2000 B 3 Mollusca 5 70.37 I I RG 240CT2000 B 3 Rhynchocoela 5 0.18 RG 240CT2000 B 3 Polychaeta 12 1.72 RG 240CT2000 c Crustacea 1 0.62 RG 240CT2000 c Rhynchocoela 2 0.97 RG 240CT2000 ' c Polychaeta 18 0.28 RG 240CT2000 c 2 Crustacea 0.15 RG 240CT2000 c 2 Rhynchocoela 2 0.27 I RG 240CT2000 c 2 Polychaeta 114 2.21 RG 240CT2000 c 3 Mollusca 1 0.64 RG 240CT2000 c 3 Polychaeta 2 0.20 I RG 10JAN2001 A Chironomid larvae 7 0.32 RG 10JAN2001 A Mollusca 6 1.27 RG 10JAN2001 A Rhynchocoela 2 0.14 RG 10JAN2001 A Polychaeta 48 2.44 RG 10JAN2001 A 2 Chironomid larvae 5 0.28 RG 10JAN2001 A 2 Mollusca 6 1.55I RG 10JAN2001 A 2 Rhynchocoela 3 0.81 I 40 I I I RG 10JAN2001 A 2 Polychaeta 39 3.34 RG 10JAN2001 A 3 Chironomid larvae 11 0.51 RG 10JAN2001 A 3 Mollusca 5 2.37 RG 10JAN2001 A 3 Rhynchocoela 4 0.56 RG 10JAN2001 A 3 Polychaeta 53 2.61 RG 10JAN2001 B Chironomid larvae 8 0.39 RG 10JAN2001 B Mollusca l 33.78 I RG 10JAN2001 B Rhynchocoela 5 0.52 RG 10JAN2001 B l Polychaeta 33 2.36 RG 10JAN2001 B 2 Chironomid larvae 2 0.11 I RG 10JAN2001 B 2 Mollusca 4 65.69 RG 10JAN2001 B 2 Rhynchocoela 1 0.01 RG 10JAN2001 B 2 Polychaeta 26 3.18 RG 10JAN2001 B 3 Chironomid larvae 3 0.22 RG 10JAN2001 B 3 Mollusca 3 0.35 RG 10JAN2001 B 3 Rhynchocoela 2 0.38I RG 10JAN2001 B 3 Polychaeta 20 1.44 I RG 10JAN2001 c 1 Chironomid larvae 4 0.35 RG 10JAN2001 c 1 Mollusca 7 1.56 RG 10JAN2001 c Rhynchocoela 1 0.16 RG 10JAN2001 c Polychaeta 60 8.04 RG 10JAN2001 c 2 Crustacea 3 0.22 RG 10JAN2001 c 2 Chironomid larvae 2 0.49I RG 10JAN2001 c 2 Mollusca 7 2.80 I RG 10JAN2001 c 2 Rhynchocoela 4 0.96 RG 10JAN2001 c 2 Polychaeta 75 8.08 RG 10JAN2001 c 3 Crustacea 1 0.03 RG 10JAN2001 c 3 Chironomid larvae 3 0.40 RG 10JAN2001 . c 3 Mollusca 8 1.04 RG 10JAN2001 c 3 Rhynchocoela 3 1.03 RG 10JAN2001 c 3 Polychaeta 56 3.67 '·I I I RG 14APR2001 A 1 Chironomid larvae 23 1.19 RG 14APR2001 A 1 Mollusca 1 0.06 RG 14APR2001 A 1 Polychaeta 28 2.60 RG 14APR2001 A 2 Crustacea 1 0.06 RG 14APR2001 A 2 Chironomid larvae 34 1.34 RG 14APR2001 A 2 Polychaeta 27 3.02 RG 14APR2001 A 3 Chironomid larvae 31 1.47 RG 14APR2001 A 3 Rhynchocoela 4 1.19 RG 14APR2001 A 3 Polychaeta 44 4.61 I RG 14APR2001 B Chironomid larvae 17 4.25 I RG 14APR2001 B Mollusca 1 0.78 RG 14APR2001 ' B 1 Polychaeta 16 1.50 RG 14APR2001 B 2 Chironomid larvae 27 2.42 RG 14APR2001 B 2 Polychaeta 30 2.40 RG 14APR2001 B 3 Chironomid larvae 15 1.13 RG 14APR2001 B 3 Mollusca 0.13 I RG 14APR2001 B 3 Rhynchocoela 2 0.43 I RG 14APR2001 B 3 Polychaeta 20 2.16 RG 14APR2001 c Chironomid larvae 20 4.57 RG 14APR2001 c Mollusca 2 23 .91 RG 14APR2001 c Rhynchocoela 2 0.66 RG 14APR2001 c Polychaeta 66 5.38 RG 14APR2001 c 2 Chironomid larvae 12 1.26I RG 14APR2001 c 2 Mollusca 3 2.62 I 41 I I RG 14APR2001 c 2 Rhynchocoela 1 0.31 RG 14APR2001 c 2 Polychaeta 36 1.77 RG 14APR2001 c 3 Chironomid larvae 19 1.47 RG 14APR2001 c 3 Mollusca 2 24.81 RG 14APR2001 c 3 Rhynchocoela 1 0.51 RG 14APR2001 c 3 Polychaeta 30 2.45I RG 07JUL2001 A Chironomid larvae 12 0.23 I I RG 07JUL2001 A 1 Mollusca 0.23 RG 07JUL2001 A 1 Rhynchocoela 2 1.50 RG 07JUL2001 A 1 Polychaeta 37 1.57 RG 07JUL2001 A 2 Chironomid larvae 3 0.49 RG 07JUL2001 A 2 Mollusca 1 0.21 RG 07JUL2001 A 2 Polychaeta 24 1.79 RG 07JUL2001 A 3 Chironomid larvae 2 0.04 I RG 07JUL2001 A 3 Mollusca 1 2.48 RG 07JUL2001 A 3 Polychaeta 8 1.60 RG 07JUL2001 B 1 Chironomid larvae 4 0.15 I RG 07JUL2001 B 1 Polychaeta 19 1.42 RG 07JUL2001 B 2 Chironomid larvae 4 0.11 RG 07JUL2001 B 2 Mollusca 1 28.73 RG 07JUL2001 B 2 Polychaeta 16 1.20 I RG 07JUL2001 B 3 Chironomid larvae 6 0.40 RG 07JUL2001 B 3 Mollusca 3 84.24 RG 07JUL2001 B 3 Polychaeta 14 1.15 I RG 07JUL2001 c Chironomid larvae 5 3.04 RG 07JUL2001 c 1 Polychaeta 7 0.34 RG 07JUL2001 c 2 Chironomid larvae 2.08 RG 07JUL2001 c 2 Rhynchocoela 1 0.20 RG 07JUL2001 . c 2 Polychaeta 1 0.07 RG 07JUL2001 c 3 Chironomid larvae 4 0.36 ;,;I I RG 07JUL2001 c 3 Rhynchocoela 1 1.64 RG 07JUL2001 c 3 Other 1 0.01 RG 07JUL2001 c 3 Polychaeta 3 2.92 SB 240CT2000 A Crustacea 5 12.40 SB 240CT2000 A 1 Mollusca 3 0.85 SB 240CT2000 A 1 Rhynchocoela 1 0.02 SB 240CT2000 A 1 Polychaeta 80 5.06I SB 240CT2000 A 2 Rhynchocoela 2.26 I SB 240CT2000 A 2 Polychaeta 17 5.84 SB 240CT2000 A 3 Crustacea 1 0.02 SB 240CT2000 A 3 Polychaeta 51 12.90 SB 240CT2000 B Polychaeta 54 1.21 I I SB 240CT2000 B 2 Crustacea 5 0.08 SB 240CT2000 B 2 Rhynchocoela 1 0.12 SB 240CT2000 B 2 Polychaeta 36 1.23 I SB 240CT2000 B 3 Crustacea 4 0.43 SB 240CT2000 B 3 Polychaeta 53 2.56 SB 10JAN2001 A Crustacea 13 0.48 I SB 10JAN2001 A Rhynchocoela 0.01 SB 10JAN2001 A 1 Polychaeta 221 55.05 SB 10JAN2001 A 2 Crustacea 20 1.53 SB 10JAN2001 A 2 Mollusca 3 1.92 I SB 10JAN2001 A 2 Rhynchocoela 4 0.15 SB 10JAN2001 A 2 Other 0.27 SB IOJAN2001 A 2 Polychaeta 231 21.42 I 42 I I SB 10JAN2001 A 3 Crustacea 9 0.46 SB 10JAN2001 A 3 Mollusca l 0.59 SB 10JAN2001 A 3 Rhynchocoela 2 0.03 SB 10JAN2001 A 3 Polychaeta 176 96.32 SB 10JAN2001 B l Crustacea 2 0.03 SB 10JAN2001 B Mollusca 12 4.57I SB 10JAN2001 B Polychaeta 60 3.28 I SB 10JAN2001 B 2 Crustacea 2 0.46 SB 10JAN2001 B 2 Mollusca 13 0.55 SB 10JAN2001 B 2 Other 2 0.07 SB 10JAN2001 B 2 Polychaeta 95 7.71 SB 10JAN2001 B 3 Crustacea 7 0.44 SB 10JAN2001 B 3 Mollusca 16 2.03 I SB 10JAN2001 B 3 Pol)'chaeta 128 11.73 I Macrofaunal Community Structure I Table 8. Species abundance data. Abbreviations: Bay (East Matagorda Bay = EM, Brazos River =BR, Rio Grande= RG, South Bay= SB), REP= replicate, n =number of individuals. Sample core area is 35.3 cm2, multiply by 283 to obtain n m2• I Bay Date STA REP SEecies n/core EM 190CT2000 B 1 Amphiodia atra 2 I EM 190CT2000 B Aricidea catharinae 4 EM 190CT2000 B Cirrophorus lyra 2 EM 190CT2000 . B Lumbrineris parvapedata 1 EM 190CT2000 B Malmgreniella taylori 1"I EM 190CT2000 B Mediomastus ambiseta 26 I EM 190CT2000 B Mulinia lateralis 5 EM 190CT2000 B 1 Pandora trilineata 1 EM 190CT2000 B 2 Amphiodia atra 1 EM 190CT2000 B 2 Cirrophorus l yra 6 EM 190CT2000 B 2 Clymenella torquata 2 EM 190CT2000 B 2 Cossura delta I EM 190CT2000 B 2 Glycinde solitaria I EM 190CT2000 B 2 Gyptis vittata 2 EM 190CT2000 B 2 Lumbrineris parvapedata 2 EM 190CT2000 B 2 Mediomastus ambiseta 29 EM 190CT2000 B 2 Melinna maculata EM 190CT2000 ' B 2 Mulinia lateralis 13 EM 190CT2000 B 3 Aligena texasiana 3I EM 190CT2000 B 3 Amphiodia atra 1 EM 190CT2000 B 3 Cirrophorus lyra 8 EM 190CT2000 B 3 Clymenella torquata 2 I EM 190CT2000 B 3 Glycinde solitaria 1 EM 190CT2000 B 3 Gyptis vittata 3 EM 190CT2000 B 3 Hemicyclops sp. 2 EM 190CT2000 B Lumbrineris parvapedata EM 190CT2000 B 3 Mediomastus ambiseta 14 I 3 3 I EM 190CT2000 B 3 Mulinia lateralis 5 EM 190CT2000 B 3 Mysella planulata EM 190CT2000 B 3 Phoronis architecta 3 EM 190CT2000 B 3 Pyrgiscus sp. I 43 I I I EM 190CT2000 B 3 Spiochaetopterus costarum EM 190CT2000 B 3 Tharyx setigera EM 190CT2000 c Amphiodia atra l EM 190CT2000 c Aricidea catharinae 3 EM 190CT2000 c Branchioasychis americana I EM 190CT2000 c Cirrophorus lyra l EM 190CT2000 c Lumbrineris parvapedata l I I EM 190CT2000 c Mediomastus ambiseta 13 EM 190CT2000 c Pyrgiscus sp. l EM 190CT2000 c 2 Acteocina canaliculata 1 EM 190CT2000 c 2 Aricidea catharinae 10 EM 190CT2000 c 2 Branchioasychis americana 3 EM 190CT2000 c 2 Cossura delta 1 EM 190CT2000 c 2 Euclymene sp. B 1 EM 190CT2000 c 2 Glycinde solitaria 1 EM 190CT2000 c 2 Gyptis vittata 1 I EM 190CT2000 c 2 Lumbrineris parvapedata 2 I EM 190CT2000 c 2 Mediomastus ambiseta 27 EM 190CT2000 c 2 Melinna maculata 1 EM 190CT2000 c 2 Mulinia lateralis 3 EM 190CT2000 c 2 Mysella planulata 1 EM 190CT2000 c 2 Paraprionospio pinnata 1 EM 190CT2000 c 2 Phoronis architecta 1I EM 190CT2000 c 2 Pyrgiscus sp. 2 I EM 190CT2000 c 2 Rhynchocoela (unidentified) 2 EM 190CT2000 c 3 Amphiodia atra 1 EM 190CT2000 c 3 Aricidea catharinae 1 EM 190CT2000 c 3 Branchioasychis americana EM 190CT2000 c 3 Cyclopoid copepod (commensal) 1 EM 190CT2000 c 3 Euclymerie sp. B 2 !:.""' I I <.I EM 190CT2000 c 3 Glycinde solitaria 1 EM 190CT2000 c 3 Lumbrineris parvapedata 3 EM 190CT2000 c 3 Mediomastus ambiseta 18 EM 190 CT2000 c 3 Mulinia lateralis 2 EM 190CT2000 c 3 Pinnixa sp. 1 EM 190CT2000 F Aricidea catharinae 4 EM 190CT2000 F Branchioasychis americana EM 190CT2000 F Cossura delta 2 EM 190CT2000 F Listriella barnardi EM 190CT2000 F Lumbrineris parvapedata 1I EM 190CT2000 F 1 Mediomastus ambiseta 22 I EM 190CT2000 F Megalomma bioculatum 1 EM 190CT2000 ' F Mulinia lateralis 1 EM 190CT2000 F Mysella planulata 2 EM 190CT2000 F Polydora caulleryi 4 EM 190CT2000 F 1 Rhynchocoela (unidentified) 1 EM 190CT2000 F 2 Amphiodia atra I EM 190CT2000 F 2 Aricidea catharinae 7 I EM 190CT2000 F 2 Cossura delta EM 190CT2000 F 2 Mediomastus ambiseta 20 EM 190CT2000 F 2 Mulinia lateralis l EM 190CT2000 F 2 Polydora caulleryi 2 EM 190CT2000 F 2 Rhynchocoela (unidentified) EM 190CT2000 F 2 Turbellaria (unidentified) I EM 190CT2000 F 3 Amphiodia atra I 44 I I EM 190 CT2000 F 3 Aricidea catharinae 6 EM 190CT2000 F 3 Cossura delta EM 190CT2000 F 3 Mediomastus ambiseta 17 I EM 190CT2000 F 3 Megalomma bioculatum l EM 190CT2000 F 3 Nassarius acutus l EM 190CT2000 F 3 Paraprionospio pinnata 2 EM 190CT2000 F 3 Polydora caulleryi 2 I EM 190CT2000 F 3 Rhynchocoela (unidentified) l EM 09JAN2001 B l Aligena texasiana l EM 09JAN2001 B l Amphiodia atra 1 I EM 09JAN2001 B l Axiothells sp. A l EM 09JAN2001 B l Cirrophorus lyra 14 EM 09JAN2001 B l Glycinde solitaria 1 EM 09JAN2001 B Gyptis vittata EM 09JAN2001 B Lumbrineris parvapedata 2 EM 09JAN2001 B Mediomastus ambiseta 30 I EM 09JAN2001 B Mulinia lateralis 11 I EM 09JAN2001 B Mysella planulata 4 EM 09JAN2001 B Polydora caulleryi 1 EM 09JAN2001 B Turbellaria (unidentified) 1 EM 09JAN2001 B 2 Amphiodia atra l I EM 09JAN2001 B 2 Aricidea catharinae 3 EM 09JAN2001 B 2 Cirrophorus lyra 2 EM 09JAN2001 B 2 Cossura delta 4 I EM 09JAN2001 B 2 Glycinde solitaria EM 09JAN2001 B 2 Lumbrineris parvapedata 2 EM 09JAN2001 B 2 Mediomastus ambiseta 35 ·1 EM 09JAN2001 B 2 Mulinia lateralis 7 EM 09JAN2001 · B 2 Paraprionospio pinnata 1 EM 09JAN2001 B 2 Phoronis architecta 1 EM 09JAN2001 B 2 Rhynchocoela (unidentified) 1 I EM . 09JAN2001 B 3 Amphiodia atra EM 09JAN2001 B 3 Cirrophorus lyra 2 EM 09JAN2001 B 3 Cyclopoid copepod (commensal) 1 I EM 09JAN2001 B 3 Leucon sp. l EM 09JAN2001 B 3 Lumbrineris parvapedata 4 EM 09JAN2001 B 3 Mediomastus ambiseta 59 EM 09JAN2001 B 3 Mulinia lateralis 9 EM 09JAN2001 B 3 Pyrgiscus sp. 1 EM 09JAN2001 B 3 Spiochaetopterus costarum I EM 09JAN2001 B 3 Turbellaria (unidentified) 1 EM 09JAN2001 c l Amphiodia atra 1 EM 09JAN2001 c 1 Aricidea catharinae 3 EM 09JAN2001 c 1 Branchioasychis americana EM 09JAN2001 c 1 Ceratonereis irritabilis I 1 EM 09JAN2001 c 1 Cirrophorus lyra l EM 09JAN2001 c Cossura delta 2I EM 09JAN2001 c Glycinde solitaria I EM 09JAN2001 c Leucon sp. 1 EM 09JAN2001 c Lumbrineris parvapedata 3 EM 09JAN2001 c Mediomastus ambiseta 36 I EM 09JAN2001 c Paraprionospio pinnata EM 09JAN2001 c 2 Acteocina canaliculata EM 09JAN200l c 2 Amphiodia atra EM 09JAN200l c 2 Aricidea catharinae 4 I 45 I I EM 09JAN2001 c 2 Branchioasychis americana 7 EM 09JAN2001 c 2 Ceratonereis irritabilis EM 09JAN2001 c 2 Cirrophorus lyra 15 I EM 09JAN2001 c 2 Glycera americana EM 09JAN2001 c 2 Gyptis vittata 4 EM 09JAN2001 c 2 Mediomastus ambiseta 65 EM 09JAN2001 c 2 Nassarius acutus 1 I I EM 09JAN2001 c 2 Paraprionospio pinnata 6 EM 09JAN2001 c 2 Phoronis architecta 1 EM 09JAN2001 c 2 Polydora caulleryi 2 EM 09JAN2001 c 2 Rhynchocoela (unidentified) 2 EM 09JAN2001 c 3 Amphiodia atra 1 EM 09JAN2001 c 3 Aricidea catharinae 6 EM -09JAN2001 c 3 Axiothells sp. A 2 EM 09JAN2001 c 3 Branchioasychis americana 1 EM 09JAN2001 c 3 Cirrophorus lyra 20 I EM 09JAN2001 c 3 Gyptis vittata 6 I EM 09JAN2001 c 3 Lumbrineris parvapedata 2 EM 09JAN2001 c 3 Mediomastus ambiseta 59 EM 09JAN2001 c 3 Paraprionospio pinnata 1 EM 09JAN2001 c 3 Phoronis architecta 2 EM 09JAN2001 c 3 Polydora caulleryi 2 EM 09JAN2001 c 3 Rhynchocoela (unidentified) 1I EM 09JAN2001 F Cossura delta I I EM 09JAN2001 F Mediomastus ambiseta 13 EM 09JAN2001 F Mulinia lateralis 1 EM 09JAN2001 F Paraprionospio pinnata 2 EM 09JAN2001 F l Streblospio benedicti 4 EM 09JAN2001 F 2 Corophium sp. 1 EM 09JAN2001 F 2 Cossura delta 4 ~1 EM 09JAN2001 F 2 Mediomastus ambiseta 32 EM 09JAN2001 F 2 Oligochaetes (unidentified) 1 EM 09JAN2001 F 2 Paraprionospio pinnata 2 EM 09JAN2001 F 2 Streblospio benedicti 3 I EM 09JAN2001 F 3 Cossura delta 3 EM 09JAN2001 F 3 Mediomastus ambiseta 19 EM 09JAN2001 F 3 Oligochaetes (unidentified) 1 EM 09JAN2001 F 3 Paraprionospio pinnata 1 I EM 09JAN2001 F 3 Streblospio benedicti 11 EM 09JAN2001 F 3 Tharyx setigera 1 EM 09APR2001 B Amphiodia atra 1 I EM 09APR2001 B Aricidea catharinae 4 EM 09APR2001 B Axiothells sp. A 2 EM 09APR2001 B Cirrophorus Iyra 7 EM 09APR2001 B Gyptis vittata 1 EM 09APR2001 B Lumbrineris parvapedata 2 EM 09APR2001 B Mediomastus ambiseta 27 I EM 09APR2001 B Melinna maculata 1 EM 09APR2001 B Mulinia lateralis EM 09APR2001 B Oxyurostylis sp. I EM 09APR2001 B Paraprionospio pinnata EM 09APR2001 B Phoronis architecta EM 09APR2001 B Polydora caulleryi EM 09APR2001 B Spiochaetopterus costarum I EM 09APR2001 B Turbellaria (unidentified) I 46 I I EM 09APR2001 B 2 Branchioasychis americana 2 EM 09APR2001 B 2 Clymenella torquata 2 EM 09APR2001 B 2 Cossura delta 2 I EM 09APR2001 B 2 Gyptis vittata 1 EM 09APR2001 B 2 Lumbrineris parvapedata 6 EM 09APR2001 B 2 Mediomastus ambiseta 18 EM 09APR2001 B 2 Mulinia lateralis 3 EM 09APR2001 B 2 Nereidae (unidentified) 1 EM 09APR2001 B 2 Paraprionospio pinnata 1 I EM 09APR2001 B 2 Polydora caulleryi 2 I EM 09APR2001 B 3 Amphiodia atra 1 EM 09APR2001 B 3 Aricidea catharinae 4 EM 09APR2001 B 3 Axiothells sp. A 1 EM 09APR2001 B 3 Branchioasychis americana 2 EM 09APR2001 B 3 Cirrophorus I yra 10 EM 09APR2001 B 3 Clymenella torquata I EM 09APR2001 B 3 Cossura delta 2 I EM 09APR2001 B 3 Glycinde solitaria EM 09APR2001 B 3 Gyptis vittata 1 EM 09APR2001 B 3 Lumbrineris parvapedata 4 EM 09APR2001 B 3 Mediomastus ambiseta 38 I EM 09APR2001 B 3 Mulinia lateralis 4 EM 09APR2001 B 3 Phoronis architecta 1 EM 09APR2001 B 3 Polydora caulleryi 3 I I EM 09APR2001 B 3 Rhynchocoela (unidentified) 1 EM 09APR2001 B 3 Turbellaria (unidentified) 2 EM 09APR2001 c Amphiodia atra 1 EM 09APR2001 c 1 Aricidea catharinae 5 EM 09APR2001 · c 1 Axiothells sp. A 1 EM 09APR2001 c 1 Branchioasychis americana 3 EM 09APR2001 c 1 Cirrophorus lyra 13 EM 09APR2001 c 1 Cossura delta 2 EM 09APR2001 c 1 Cyclopoid copepod (commensal) 1 I EM 09APR2001 c 1 Glycera americana 1 I EM 09APR2001 c 1 Glycinde solitaria 1 EM 09APR2001 c 1 Leucon sp. 1 EM 09APR2001 c 1 Lumbrineris parvapedata 5 EM 09APR2001 c 1 Mediomastus ambiseta 19 EM 09APR2001 c 1 Mulinia lateralis 4 EM 09APR2001 c Paraprionospio pinnata I EM 09APR2001 c 1 Rhynchocoela (unidentified) I EM 09APR2001 c 1 Streblospio benedicti 4 EM 09APR2001 c 2 Acteocina canaliculata 1 EM 09APR2001 c 2 Ampelisca abdita 3 EM 09APR2001 c 2 Amphiodia atra 1 EM 09APR2001 c 2 Aricidea catharinae 9 EM 09APR2001 c 2 Axiothells sp. A 4I EM 09APR2001 c 2 Branchioasychis americana 8 I EM 09APR2001 c 2 Cirrophorus lyra 12 EM 09APR2001 c 2 Glycera americana 2 EM 09APR2001 c 2 Gyptis vittata I EM 09APR2001 c 2 Leucon sp. 1 EM 09APR2001 c 2 Lumbrineris parvapedata 6 EM 09APR2001 c 2 Mediomastus ambiseta 38 EM 09APR2001 c 2 Melinna maculata 3 I 47 I I EM 09APR2001 c 2 Mulinia lateralis 5 EM 09APR2001 c 2 Paranaitis speciosa EM 09APR2001 c 2 Paraprionospio pinnata 2 I EM 09APR2001 c 2 Rhynchocoela (unidentified) 3 EM 09APR2001 c 2 Streblospio benedicti 3 EM 09APR2001 c 3 Acteocina canaliculata EM 09APR2001 c 3 Ampelisca abdita EM 09APR2001 c 3 Amphiodia atra 1 EM 09APR2001 c 3 Aricidea catharinae 4 I EM 09APR2001 c 3 Axiothells sp. A 2 I EM 09APR2001 c 3 Branchioasychis americana 3 EM 09APR2001 c 3 Cirrophorus lyra 2 EM 09APR2001 c 3 Lumbrineris parvapedata 4 EM 09APR2001 c 3 Mediomastus ambiseta 41 EM 09APR2001 c 3 Mulinia lateralis 11 EM 09APR2001 c 3 Paraprionospio pinnata 3I EM 09APR2001 c 3 Phoronis architecta 1 I EM 09APR2001 c 3 Pyrgiscus sp. 1 EM 09APR2001 F 1 Ancistrosyllis sp. 1 EM 09APR2001 F Axiothells sp. A 1 EM 09APR2001 F Cirrophorus lyra 2 EM 09APR2001 F Clymenella torquata 1 EM 09APR2001 F Cossura delta 2I EM 09APR2001 F 1 Drilonereis magna 1 I EM 09APR2001 F 1 Glycinde solitaria 1 EM 09APR2001 F 1 Haploscoloplos fragilis 1 EM 09APR2001 F 1 Mediomastus ambiseta 24 EM 09APR2001 F 1 Streblospio benedicti 1 EM 09APR2001 F 1 Turbellaria (unidentified) 1;I EM 09APR2001 F 2 Aligena texasiana 1 I EM 09APR2001 F 2 Ancistrosyllis sp. 1 EM 09APR2001 F 2 Anthozoa (unidentified) 2 EM 09APR2001 F 2 Aricidea catharinae 6 EM 09APR2001 F 2 Axiothells sp. A I EM 09APR2001 F 2 Branchioasychis americana 2 EM 09APR2001 F 2 Cirrophorus lyra 1 EM 09APR2001 F 2 Clymenella torquata 4 EM 09APR2001 F 2 Cossura delta 1 EM 09APR2001 F 2 Glycinde solitaria 1 EM 09APR2001 F 2 Haploscoloplos fragilis 1I EM 09APR2001 F 2 Mediomastus ambiseta 30 EM 09APR2001 F 2 Melinna maculata 2 EM 09APR2001 ' F 2 Mulinia lateralis 2 EM 09APR2001 F 2 Paraprionospio pinnata EM 09APR2001 F 2 Rhynchocoela (unidentified) 1 I 3 EM 09APR2001 F 2 Streblospio benedicti 3 EM 09APR2001 F 2 Tharyx setigera I EM 09APR2001 F 3 Aricidea catharinae 4 I EM 09APR2001 F 3 Axiothells sp. A 2 EM 09APR2001 F 3 Clymenella torquata l EM 09APR2001 F 3 Cossura delta 5 EM 09APR2001 F 3 Mediomastus ambiseta 22 EM 09APR2001 F 3 Melinna maculata l EM 09APR2001 F 3 Mulinia lateralis 5I EM 09APR2001 F 3 Rhynchocoela (unidentified) 2 I 48 I I I EM 09APR2001 F 3 Streblospio benedicti 4 EM l 1JUL2001 B Aligena texasiana 7 EM 11JUL2001 B Amphiodia atra 1 EM 11JUL2001 B Aricidea catharinae I EM 11JUL2001 B Branchioasychis americana I EM 11JUL2001 B Caecum johnsoni 7 EM 11JUL2001 B Cirrophorus lyra 30 I EM l 1JUL2001 B Gyptis vittata 4 EM l 1JUL2001 B Lumbrineris parvapedata 4 EM 11JUL2001 B Mediomastus ambiseta 33 I EM 11JUL2001 B Microprotopus spp. I EM 11JUL2001 B Mysella planulata 3 EM 11JUL2001 B Phoronis architecta I EM 11JUL2001 B Polydora caulleryi I EM 11JUL2001 B Rhynchocoela (unidentified) I EM 11JUL2001 B 2 Aligena texasiana 4 I EM 11JUL2001 B 2 Amphiodia atra 2 I EM 11JUL2001 B 2 Aricidea catharinae 3 EM 11JUL2001 B 2 Branchioasychis americana . ··---J EM 11JUL2001 B 2 Cirrophorus lyra 17 EM 11JUL2001 B 2 Clymenella torquata 2 EM 11JUL2001 B 2 Gyptis vittata I EM 11JUL2001 B 2 Lumbrineris parvapedata 4I EM 11JUL2001 B 2 Mediomastus ambiseta 25 I I EM 11JUL2001 B 3 Amphiodia atra 2 EM 11JUL2001 B 3 Aricidea catharinae I EM 11JUL2001 B 3 Branchioasychis americana I EM llJUL2001 B 3 Cirrophorus lyra 16 EM 11JUL2001 . B 3 Clymenella torquata I EM 11JUL2001 B 3 Cossura delta 3 EM 11JUL2001 B 3 Gyptis vittata I I I EM 11JUL2001 B 3 Leucon sp. I EM llJUL2001 B 3 Lumbrineris parvapedata 4 EM I IJUL2001 B 3 Mediomastus ambiseta 18 EM 11JUL2001 B 3 Paraprionospio pinnata 1 EM 11JUL2001 B 3 Pyrgiscus sp. I EM 11JUL2001 B 3 Rhynchocoela (unidentified) I EM llJUL2001 B 3 Spiochaetopterus costarum I EM llJUL2001 B 3 Tharyx setigera 1 EM 11JUL2001 c Branchioasychis americana I EM I 1JUL2001 c Leucon sp. I EM 11JUL2001 c Lumbrineris parvapedata 2 EM 11JUL2001 c Mediomastus ambiseta 9 EM 11JUL2001 c Paraprionospio pinnata I EM 11JUL2001 c Rhynchocoela (unidentified) 1 EM 11JUL2001 c 2 Aricidea catharinae 7 EM 11JUL2001 c 2 Branchioasychis americana I EM 11JUL2001 c 2 Gyptis vittata I EM 11JUL2001 c 2 Lumbrineris parvapedata 1 EM 11JUL2001 c 2 Mediomastus ambiseta 9 EM l 1JUL2001 c 2 Paraprionospio pinnata EM l 1JUL2001 c 2 Pilargis berkelyae I EM l 1JUL2001 c 3 Amphiodia atra 1 EM l 1JUL2001 c 3 Aricidea catharinae 3 EM l 1JUL2001 c 3 Branchioasychis americana 4 I 49 I I EM 11JUL2001 c 3 Cirrophorus lyra 15 EM 11JUL2001 c 3 Cossura delta 1 I EM 11JUL2001 c 3 Gyptis vittata 1 I EM l 1JUL2001 c 3 Lumbrineris parvapedata 3 EM l 1JUL2001 c 3 Mediomastus ambiseta 15 EM 11JUL2001 c 3 Rhynchocoela (unidentified) 1 EM 11JUL2001 c 3 Streblospio benedicti 1 EM l 1JUL2001 F Aricidea catharinae 1 EM 11JUL2001 F Cossura delta 3I EM l 1JUL2001 F Mediomastus ambiseta 11 I EM 11JUL2001 F Mulinia lateralis 1 EM l 1JUL2001 F Rhynchocoela (unidentified) 1 EM 11JUL2001 F 1 Streblospio benedicti 5 EM 11JUL2001 F 1 Vitrinellidae (unidentified) EM 11JUL2001 F 2 Aricidea catharinae 2 EM 11JUL2001 F 2 Cossura delta 11I EM 11JUL2001 F 2 Glycinde solitaria 1 I EM 11JUL2001 F 2 Mediomastus ambiseta 15 EM 11JUL2001 F 2 Streblospio benedicti 7 EM 11JUL2001 F 3 Cossura delta 2 I EM 11JUL2001 F 3 Glycinde solitaria EM 11JUL2001 F 3 Mediomastus ainbiseta 8 EM 11JUL2001 F 3 Streblospio benedicti 17 BR 180CT2000 A 1 Mediomastus ambiseta 4 I BR 180CT2000 A 1 Streblospio benedicti 37 BR 180CT2000 A 2 Cossura delta 1 BR 180CT2000 A 2 Mediomastus ambiseta 6 BR 180CT2000 A 2 Streblospio benedicti 34 BR 180CT2000 A 3 Cossura delta 1 BR 180CT2000 A 3 Mediomastus ambiseta 6