Texas Natural History Collection - Fishes - Publications

Permanent URI for this collection


Recent Submissions

Now showing 1 - 20 of 67
  • Item
    El Diccionario Tarahumara –Alemán de Matthäus Steffel: Lengua y Cultura Rarámuri en el Siglo XVIII
    (Universidad de Sonora, Hermosillo, Sonora, México, 2020) Merrill, William L.
    El Diccionario Tarahumara-Alemán de Matthäus Steffel: Lengua y Cultura Rarámuri en el Siglo XVIII, by William L. Merrill, in collaboration with Maria Brumm and Greta de León. Hermosillo, Sonora, Mexico: Universidad de Sonora. 1103 pages. Tarahumara, an Indigenous language of northwestern Mexico, is spoken today by more than 80,000 people, who refer to themselves and their language as "Rarámuri". It is related to over thirty other languages that together form the Uto-Aztecan language family, distributed at European contact from the Great Basin of the western United States to Central America. The only extant dictionary of the Tarahumara language produced prior to the twentieth century was compiled in German by the Moravian Jesuit Matthäus Steffel, based on his experience as a missionary among the Tarahumaras between 1761 and 1767. The dictionary was published in Germany in 1809, but it contains hundreds of mistakes, both typographical and substantive, suggesting that Steffel did not have the opportunity to review it before his death in 1806. Fortunately, the majority of these mistakes can be corrected by comparison with a manuscript version of the dictionary that is preserved in the Moravian Provincial Archives, located in Brno, Czech Republic, where Steffel lived during the last three decades of his life. This volume offers the first Spanish translations and detailed analyses of both the published and manuscript versions of Steffel's Tarahumara-German dictionary, as well as exact transcriptions of the German originals of both works. Its principal objectives are to make the dictionary accessible to the Rarámuri people and to enhance its value as a source of data for research in linguistics and other disciplines. Steffel documented over 1100 Tarahumara words, along with diverse dimensions of the phonology, morphology, syntax, and semantics of the language in the eighteenth century. The record he created indicates that, during the last 250 years, the Tarahumara language has undergone significant changes that have tended to distance it from other Uto-Aztecan languages. His dictionary is crucial to clarifying the historical relationships between Tarahumara and these languages as well as the nature and temporal framework of the changes that occurred. In addition, Steffel enriched his lexical entries with precise descriptions of a range of Tarahumara cultural practices and various aspects of life in colonial Mexico, and he provided the first descriptions of the flora and fauna of the Tarahumara region. The translations and transcriptions of the dictionary presented in this volume are complemented by overviews of Steffel=s life and his linguistic endeavors and evaluations of the significance of these works for research on Tarahumara language and cultural history. To transform his studies into reliable sources of linguistic data and to facilitate their use in linguistic research, the volume presents a technical analysis of his orthographic conventions, along with an extensive review of the errors identified in the works, a presentation of the words and glosses documented in the published dictionary in separate Tarahumara-Spanish and Spanish-Tarahumara vocabulary lists, and a compilation of these lexical items rendered in Steffel's orthography and modern phonetic notation. A glossary of the plant and animal terms that Steffel documented is presented separately with postulated scientific identifications of the taxa designated by them. An index of the principal topics covered in the published dictionary also is provided.
  • Item
    General Fish Surveys on Selected Texas National Guard Properties: Camp Bowie, Camp Mabry, Camp Maxey, Camp Swift and Fort Wolters
    (2007-12) Hendrickson, Dean; Cohen, Adam
    The Texas Natural History Collection of the Texas Natural Science Center was contracted to conduct a fish survey on five Texas Military Forces facilities in Texas, including: Camp Mabry (Travis County), Camp Swift (Bastrop county), Camp Bowie (Brown county), Camp Maxey (Lamar County), and Fort Wolters (Parker County). This is the second fish survey completed for the properties. The first was completed by the Texas Parks and Wildlife Department (TPWD) in 1995 and included a total of 27 species, representing eight families collected from the five properties. During the course of this survey, 39 species were collected, representing 10 families. New records include Aplodinotus grunniens, Carpiodes carpio, Cyprinus carpio, Esox niger, Etheostoma parvipinne, Lepisosteus oculatus, Minytrema melanops, Notropis texanus, Percina macrolepida, Percina carbonaria, Pomoxis nigromaculatus, and Pylodictis olivaris. Species which we were not able to re collect include Astyanax mexicanus and Pimephales promelas. Three species were widely distributed and collected at every base: Micropterus salmoides, Lepomis macrochirus, and Gambusia affinis. The most species-rich family was Centrarchidae and within that, Lepomis was the most species-rich genus with eight species. Consistent amongst the five bases, diversity ranked highest in perennial streams, lowest in lentic habitats, and intermediate in intermittent streams.
  • Item
    Fishes of Texas Project: update and future
    (2023-02-23) Hendrickson, Dean; Cohen, Adam; Garrett, Gary
    Fish occurrence data are widely scattered and mostly not published as data readily utilizable by computers. Global biodiversity aggregating services (e.g. GBIF, iDigBio, Fishnet) now aggregate and serve whatever data are submitted to them in the standard Darwin Core format, but their data are often replete with errors, minimally normalized, lacking content across standard fields, and served via generic mapping services lacking linkages to local and aquatic ecology-relevant resources (i.e., for fishes, they are ignorant of hydrography). In contrast, Fishes of Texas (FoTX) includes the same data and much more, including unpublished data from more diverse sources. FoTX’s rigorous quality-control measures, including specimen-based ID verifications, checking of legacy georeferencing, and flagging suspicious records has combined to greatly reduce errors. The custom FoTX website provides interactive exploration and data summarization, within the context of geopolitical and, now geographically-expanded hydrographic coverages, thus facilitating visualization and discovery of conservation-relevant histories and trends over time. The site allows viewing of derivative products, such as niche models, estimates of native ranges, checklists, data dashboards, and Native Fish Conservation Areas. The site also serves extensive image collections, collectors’ field notes, and links to digitized, formerly inaccessible unpublished agency reports. Finally, core FoTX data fields are also published to GBIF as Darwin Core to make it available to the world.
  • Item
    Testing An Alternative Shelving Arrangement to Optimize Space and Task Efficiency in a Fluid Fish Collection
    (2022-06-04) Cohen, Adam E.; Hendrickson, Dean A.; Casarez, Melissa J.
    For centuries, a taxonomic and alphabetic arrangement (TAA) of objects on shelves prevailed in fluid-preserved natural history collections while they were managed mostly by scientists for their own or vistors’ on-site research using physical specimens. However, most modern collections are now databased and internet-accessible, facilitating diverse forms of research accomplished remotely and decreasing the frequency of need for physical access to specimens, yet the way specimens are shelved and accessed remains nearly universally unchanged. With our fish collection struggling with both severe space limitation and unprecedented rapid growth supporting externally funded research that requires rapid specimen processing and data publication, we started shelving in an object (jar) and catalog number-based arrangement (OCA). To make that possible in our limited and near-full space, without altering our physical shelves in any way, we eliminated all between-jar spaces in our collection, including the customary space between taxa, while keeping it in its original TAA-based order (thus eliminating TAA-based growth capacity. In the resultant empty shelf space, we implemented an OCA shelving system for all newly cataloged jars. Once the OCA contained a relatively large number of jars, we carried out pragmatic, TAA-OCA comparisons. Volumetric jar storage capacity in the OCA is 17% > TAA, and adjusting the OCA’s vertical shelf spacing to optimize for each of our 3 jar sizes (impossible in the TAA), could increase that to 115% > TAA. Ten of 15 routine staff tasks were more efficiently accomplished in the OCA than in the TAA, and the OCA greatly decreases shelving errors (misplacement). We discuss ways to improve efficiency in the OCA for the 5 tasks on which the TAA out-performed it, and report ancillary, unanticipated benefits, such as a way to much more efficiently and quickly monitor fluid levels across all jars. All newly cataloged specimen jars continue going into our OCA, and we have significantly postponed hitting the point of absolutely being unable to continue growing. We are hopeful that eventually, a move to a new space will enable conversion of the entire collection from TAA to a more fully-optimized OCA.
  • Item
    Conservation of Texas freshwater fish diversity: selection of Species of Greatest Conservation Need
    (Texas Parks and Wildlife Dept, 2020) Birdsong, Timothy; Garrett, Gary; Bean, Megan; Bean, Preston; Curtis, Stephen; Fleming, Paul; Grubh, Archis; Lutz-Carrillo, Dijar; Mayes, Kevin; Robertson, Clint; Robertson, Sarah; Schlechte, Warren; Smith, Nathan
  • Item
    Goodenough Spring Catchment Area Characterization, Amistad Reservoir, Rio Grande Valley
    (Southwest Research Institute, San Antonio, Texas 78238-5166, 2021-12) Flores, Mauricio Eduardo; Nunu, Rebecca R.; Wittmeyer, Gordon; Green, Ronald T.
    Goodenough Spring is a major spring discharging more than 100,000 acre-ft/yr into the Rio Grande prior to the construction of Amistad Reservoir and about 51,900 acre-ft/year after its construction along the Texas-Coahuila de Zaragoza border, making it a key component of the area’s water budget (Reeves and Small, 1973; Brune, 1975; Green and Bertetti, 2010) (Figures 1 and 2). Historically, the catchment area for Goodenough Spring was thought to be located north of the Rio Grande, in the United States (Water Treaty of 1944). In recent years, however, anecdotal evidence supports the premise that the source area for Goodenough Spring is actually south of the Rio Grande, in Mexico (Thomas, 1963; Kamps and Groeger, 2006; Kamps et al., 2009). The lack of an established characterization of Goodenough Spring’s catchment area limits effective management of the region’s water quality, since the properties and hydrology of a spring’s catchment area play an integral role in determining the water quality that is issued from the spring. With an improved understanding of the spring’s catchment area, the quality of water that flows into the Amistad Reservoir from Goodenough Spring can be more effectively and efficiently safeguarded. Geologic formations intersected by the Rio Grande consist of carbonate (e.g., limestone) and non-carbonate rocks, such as clastic sandstones, shales, and igneous formations. Goodenough Spring discharges from the karstic carbonate rocks of the Edwards-Trinity Aquifer (Boghici, 2004). This distinction of rock type is crucial, as it affects the quality of water that is introduced into the Rio Grande and the development of high-volume spring discharge. Surface water that recharges non-carbonate rocks moves slowly through the subsurface flow at speeds of tens of feet per year. Comparatively, flow through karstic carbonate rocks can be a kilometer per day or faster. Thus, recharge into karstic carbonate rocks is rapid and unfiltered where it enters through sinkholes and other swallets. This means recharge captured by Goodenough Spring’s catchment area may be discharged into Amistad Reservoir within days or even hours after a storm event. This makes identification and proper management of the spring catchment an area of critical importance for water quality. Development along the Rio Grande will impact the quality of runoff that recharges the river. Further degradation of recharge to Amistad Reservoir and the Rio Grande can be mitigated if the catchment area is delineated and the proper land-use practices are employed. Developing a conceptualization of Goodenough Spring’s catchment area is essential not only to the communities near the Amistad Reservoir, but to a variety of stakeholders living in the Rio Grande Valley downstream from the Amistad Reservoir and near the bays and estuaries of the Gulf of Mexico. According to the Texas Commission on Environmental Quality (TCEQ), more than 3 million people live downstream of the Amistad Reservoir (www.tceq.texas.gov). Degradation of the quality of water discharged into the Amistad Reservoir will directly impact the quality of water discharged from the Amistad Reservoir to the lower Rio Grande and to the bays and estuaries. Efforts that protect the quality of this water will directly impact the environmental and public health of the region, since 1) much of the population relies on the Rio Grande as the principal source of water, and 2) the environmental health of the Rio Grande is contingent on quality of water discharged into the river by upstream tributaries and springs. Given the importance of Goodenough Spring, this Border 2020 Program project focused on constraining the spring’s source area. The key objectives that were undertaken to contribute towards the source area delineation included: 1. Compile pre-existing environmental (e.g., hydrologic and geologic) data from the Amistad Reservoir region in Val Verde County, Texas, United States and the State of Coahuila de Zaragoza, Mexico. 2. Identify sites for water sampling in both Texas and Coahuila de Zaragoza. 3. Conduct a water sampling campaign targeting wells in Texas and Coahuila de Zaragoza as well as Goodenough Spring. 4. Send collected water samples to laboratories for water chemistry analyses. 5. Evaluate the laboratory analyses results. 6. Use the acquired water chemistry data to constrain the Goodenough Spring source area.
  • Item
    Conservation Status of Native Fishes in the Chihuahuan Desert Region of the United States: a spatial perspective
    (Desert Fishes Council, 2021) Perkin, Joshuah; Troia, Matthew; Acre, Matthew
    Native fishes in the American Southwest are in need of conservation because of anthropogenic riverscape alterations involving habitat destruction, introduction of non-native species, and dewatering. Status assessments are useful conservation planning tools, but there is a need for transparent, repeatable, and empirically-driven assessment frameworks. We present a multi-criteria status assessment framework based on publicly available geospatial data and apply this framework to native fishes occupying the United States Chihuahuan Desert region. Criteria included (1) area occupied, (2) dependence on human protected areas, (3) genetic risk from non-native congeners, (4) vulnerability to expected climate change, (5) presence of anthropogenic threats, and (6) regional endemism. Of the 65 species reviewed, four are considered globally extinct, three are considered extirpated from the region, and 10 persist but are rarely encountered. Of the remaining 48 species with recent (i.e., post 1999) records, the current assessment ranked 6 (13%) as in danger of extinction (Endangered), 11 (23%) as on a trajectory towards extinction (Vulnerable), 5 (10%) as Near-Threatened, and 26 (54%) as Least Concern. These percentages broadly matched status ranks developed by multiple conservation entities based on a meta-status metric (i.e., status of statuses) that averaged ranks from multiple, existing assessments. Of the five species listed as Endangered under the federal Endangered Species Act (ESA), three were ranked as Endangered and two were ranked as Vulnerable in the current assessment. The two species listed as Threatened under the ESA were ranked as Vulnerable in the current assessment. Three species listed as Endangered and seven species listed as Vulnerable in the current assessment are not currently listed under the ESA. Range contraction scenarios based on recent region-wide studies of four species revealed that the status scores developed here are sensitive to potential species declines. The data-driven framework developed here supplements those used by agencies at state, federal, and international scales and can be repeated over short time intervals to develop responsive and timely status assessments.
  • Item
    Fishes of Texas Project: Government-University Collaboration to Improve Science and Conservation Management
    (The Society for the Preservation of Natural History Collections and the American Institute for Conservation, 2021-06-21) Hendrickson, Dean; Cohen, Adam; Casarez, Melissa; Garrett, Gary; Birdsong, Timothy; Robertson, Sarah; Curtis, Stephen; Mayes, Kevin; Bean, Megan
    Since 2006 the Fishes of Texas (FoTX) Project at University of Texas Austin (UT) has sought to improve freshwater fish occurrence data for the state of Texas and make it openly accessible to facilitate research and improve aquatic resource management. Seven federal and state sponsors have contributed funding, but 73% of the total $2.7 million has come from US Fish and Wildlife Service’s State Wildlife Grant Program via Texas Parks and Wildlife Department (TPWD). Initially the Project focused on data digitization and compilation of strictly specimen-vouchered data, followed by georeferencing and development of an interactive website/database (http://www.fishesoftexas.org). More recently, non-vouchered citizen science, angler-based, and agency datasets have been added, thereby increasing both geographic and temporal density of records, and a selected subset of data fields for all records is now published to GBIF and iDigBio. The project’s comprehensive data aggregation (44 contributing collections), digitization, normalization, accessibility and high data quality (based, in part on extensive taxonomic determination verification via specimen examination), enabled significant advances in detection and awareness of statewide faunal trends that led to implementation of diverse management advances. Examples include improved field guides and documentation of species’ ranges, expansions and contractions, community composition shifts, improved species conservation status assessments, and documentation of both long-term expansions of invasive species and new introductions. Relatively new to the Project are statewide aquatic bioassessments - intensive fieldwork planned using tools available in our website that facilitate exploration of geographic and temporal sampling histories and reveal under-sampled areas. Consequently, gaps in knowledge of regional faunas have been steadily decreasing. The website and database are widely used; 90% of presentations on related topics at last year’s statewide fisheries meeting utilized FoTX products. This now long-term, consistent funding created a productive partnership between UT and TPWD. With the Project’s bioassessments generating specimens, and TPWD’s independent routine fish sampling increasingly depositing specimens, our collection (TNHCi - https://www.gbif.org/dataset/6080b6cc-1c24-41ff-ad7f-0ebe7b56f311) has nearly doubled in size over the last decade. Last year, TPWD’s list of Species of Greatest Conservation Need was updated, with major changes based on the improved knowledge provided by FoTX. TPWD now funds a full-time Assistant Collection Manager position focusing on bioassessments, but also doing basic collection management and supervision of student and volunteer help. Another grant-funded position, a liaison between the collection and TPWD staff, spawned the ongoing statewide Texas Native Fish Conservation Areas program that coordinates funding and actions of diverse stakeholders for watershed-scale conservation. Both externally funded UT positions participate in diverse collections-based research and outreach endeavors for both UT and TPWD. The FoTX website was developed in large part by staff in UT’s science database group in the Texas Advanced Computing Center (TACC) - a collaboration that blossomed into long-term technical support for collection database management and data publication that has since expanded to support all other collections in UT’s Biodiversity Center.
  • Item
    The Fishes of Texas Project: Government-University Collaboration to Improve Science and Conservation Management
    (YouTube, 2021-06-24) Hendrickson, Dean; Cohen, Adam; Casarez, Melissa; Garrett, Gary; Birdsong, Timothy; Robertson, Sarah; Curtis, Stephen; Mayes, Kevin; Bean, Megan
    Since 2006, the Fishes of Texas Project at University of Texas Austin has sought to improve freshwater fish occurrence data for the state of Texas and make it openly accessible to facilitate research and improve aquatic resource management. Seven federal and state sponsors have contributed funding, but 73% of the total $2.7 million has come from US Fish and Wildlife Service’s State Wildlife Grant Program via Texas Parks and Wildlife Department. Initially the Project focused on data digitization and compilation of strictly specimen-vouchered data, followed by georeferencing and development of an interactive website/database (http://www.fishesoftexas.org). More recently, non-vouchered citizen science, angler-based, and agency datasets have been added, thereby increasing both geographic and temporal density of records, and a selected subset of data fields for all records is now published to GBIF and iDigBio.
  • Item
    An Alternative Shelving Arrangement for Natural History Collection Objects to Optimize Space and Task Efficiency
    (Allen Press, 2019-09-01) Cohen, Adam; Hendrickson, Dean; Casarez, Melissa
    A taxonomic and alphabetic arrangement (TAA) of objects on shelves has prevailed in fluid-preserved natural history collections while they were managed by scientists for their own research. Now most collections are databased and internet-accessible to facilitate very different forms of research accomplished remotely by researchers who require less physical access to specimens. The collections staff who make those data available struggle to manage collection growth with limited space and budgets, while demands on them are increasing, necessitating task and space-efficient collection management solutions. We describe an alternative arrangement of objects based on their size and catalog number (OCA) that capitalizes on modern databases. Our partial implementation of this system facilitated pragmatic between-system comparisons of space use and staff time required for routine tasks. Our OCA allows 17% more jars to be stored in a given space than a TAA (not counting spaces left for growth), but adjusting vertical spacing of shelves could increase that to 115%. Ten of 15 staff tasks were more efficiently accomplished in the OCA section of the collection, and we propose ways to improve efficiency for three of the four tasks for which the TAA outperformed the OCA.
  • Item
    Dried and salted: Cumulative impacts of diminished flows and salinization on Lower Pecos River food webs
    (Desert Fishes Council, 2021) Pease, Allison; Delaune, Kelbi
    The Lower Pecos River in New Mexico and Texas, USA has experienced salinization due to exacerbation of natural saline inputs by flow alteration and irrigation practices. This situation is most pronounced in the Permian Basin region, where the negative impacts on biodiversity, particularly for the fish fauna, have been well documented. Less is known, however, about how aquatic food webs have been affected by diminished flows and salinization in the Pecos and other dryland rivers. Here, we provide a synthesis of the cumulative impacts on food web processes and trophic structure based on our work in the Lower Pecos and on research in other river systems exposed to these stressors. Impacts range from diminished availability of terrestrial basal resources to shortened food chains due to the absence of large-bodied, piscivorous fishes. Importantly, where fresh discharge from remaining springs flows into tributaries and the main stem, trophic diversity is bolstered in the Lower Pecos. This highlights the need to preserve these vital flow and resource inputs, and it provides support for the idea that flow-regime restoration in the Lower Pecos would improve ecosystem function.
  • Item
    Biogeography of Cyprinodon across the Great Plains-Chihuahuan Desert region and adjacent areas
    (Desert Fishes Council, 2021) Hoagstrom, Christopher; Osborne, Megan
    Cyprinodon is renowned for localized endemism across the North American desert. Competing molecular studies have made elucidating timing of diversification across the desert controversial. Debate has focused on Mojave Desert species, with limited evaluation of other evidence. However, the Great Plains and Chihuahuan Desert harbor more taxonomic diversity and are geographically positioned between the Gulf of México (place of origin for the genus) and Mojave Desert, making them central to understanding the evolution of all desert Cyprinodon. This study is a detailed assessment of evidence from literature spanning geomorphology, climate, and biogeography vis à vis the mtDNA phylogeny for Cyprinodon. Conclusions of Late Miocene-Early Pleistocene diversification are supported across all major clades. Future studies that could improve understanding and address ongoing dilemmas are identified. Importantly, the geography of each clade corresponds to drainage configurations and their evolution through the proposed period of diversification. Eight hypotheses are presented to address major evolutionary events, with emphasis on exploring interpretive challenges within the phylogeny. Broadly, aridity within the Late Miocene apparently facilitated inland invasion of coastal Cyprinodon along the ancestral Brazos River and Río Grande. The following Pliocene warm, wet period enabled survival and range expansion through aridland drainages and into adjacent ones. Mio-Pliocene development of the Río Grande Rift and Gila River drainages, causing inter-drainage transfers, was crucial to range expansion. Development of other Gulf of California drainages (Colorado River, Río Yaqui) played peripheral roles. Climatic cooling in the Quaternary Period evidently caused range contractions for populations living at higher latitudes and elevations. Living Cyprinodon of the desert represent an incredible legacy of Pliocene range expansion memorialized by subsequent persistence of tenacious endemic populations. Human impacts now threaten this legacy.
  • Item
    Proceedings of the Desert Fishes Council Special Publication 2021
    (Desert Fishes Council, 2021) Bean, Megan; Garrett, Gary; Hoagstrom, Christopher
  • Item
    Status Survey of Devil´s River Minnow in Historic Range with Emphasis on Coahuila, Mexico
    (Pronatura Noreste, Monterrey, Nuevo León, México, 2007-12-15) Contreras-Arquieta, Alberto; Lozano-Vilano, Ma. de Lourdes
    English - A study was carried out to document the current status of the Devil's River Minnow, Dionda diaboli Hubbs and Brown, 1956, in northern Coahuila, Mexico. Three field trips were carried out with a total of 49 localities sampled, documenting presence of 49 species of the 54 species previously registered in the area, which are from 25 genera and 12 families. Six localities were previously known for this species in Mexico, and those historical records were obtained and entered into a geographic information system. The Devil's River Minnow was found in only one of the historic locations, in the Río San Juan under the bridge on the Múzquiz - Boquillas del Carmen highway, Múzquiz, Coahuila. Habitat condition, water quality, aquatic vegetation of all historic locations, as well as an analysis of the fish community, were evaluated. We observed that temperature oscillates between 23.9 and 27.8 ºC, the salinity between 0.14 and 0.17 ppm, the dissolved oxygen between 64.9 and 90%, the pH between 7.14 and 8.03, the turbidity below 30, with little organic matter, as shown by the results for nitrites, nitrates, sulfates, calcium and magnesium. It was found that the causes of the disappearance of Dionda diaboli, in the other localities, is due to the presence of exotic species, alteration of the habitat, decrease in water level and runoff, siltation by sediments and probably due to changes in the trophic structure of the fish community. Spanish - Se realizó un estudio para conocer el estado actual de la carpa diabla, Dionda diaboli Hubbs y Brown, 1956, de la región Norte del Estado de Coahuila, México. Se efectuaron 3 salidas de campo con un total de 49 localidades visitadas, de las cuales se reportan 49 especies de las 54 registradas en la zona, repartidos en 25 géneros y 12 familias. Seis localidades son registradas de esta especie en México, con los registros obtenidos y los registros históricos se elaboró un sistema de información geográfica. Solo fue posible observar a la carpa diabla en una de las localidades históricas. En Río San Juan bajo puente, carretera Múzquiz – Boquillas del Carmen. Múzquiz, Coahuila. Se evaluó la condición de hábitat, calidad de agua, vegetación acuática de las localidades históricas así como un análisis de la comunidad de peces. Entre los parámetros ambientales observamos que la temperatura oscila entre 23.9 y 27.8 ºC, la salinidad entre 0.14 y 0.17 ppm, el oxigeno disuelto entre 64.9 y 90 %, el pH entre 7.14 a 8.03, la turbidez inferior a 30, con escasa materia orgánica, como lo muestran los resultados de nitritos, nitratos, sulfatos, calcio y magnesio. Se encontró que las causas de desaparición del Dionda diaboli, en las otras localidades se debe a la presencia de especies exóticas, alteración del hábitat, disminución del nivel de agua y escorrentía, asolvamiento por sedimentos y probablemente por los cambios en la estructura trófica de la comunidad íctica.
  • Item
    Ciénegas - Vanishing Climax Communities of the American Southwest
    (Desert Plants, 1985) Hendrickson, Dean A.; Minckley, W.L.
    The term is here applied to mid-elevation (1,000-2,000 m) wetlands characterized by permanently saturated, highly organic, reducing soils. A depauperate flora dominated by low sedges highly adapted to such soils characterizes these habitats. Progression to ciénega is dependent on a complex association of factors most likely found in headwater areas. Once achieved, the community appears stable and persistent since paleoecological data indicate long periods of ciénega conditions, with infrequent cycles of incision. We hypothesize the ciénega to be an aquatic climax community. Ciénegas and other marshland habitats have decreased greatly in Arizona in the past century. Cultural impacts have been diverse and not well documented. While factors such as grazing and streambed modifications contributed to their destruction, the role of climate must also be considered. Ciénega conditions could be restored at historic sites by provision of constant water supply and amelioration of catastrophic flooding events.
  • Item
    Peces y Aguas Continentales del Estado de Tamaulipas, México
    (Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Monterrey, Nuevo León, México, 2004-09) Contreras-Balderas, Salvador; Lozano-Vilano, Ma. de Lourdes; García-Ramírez, María Elena; García De León, Francisco Javier; Gutiérrez Tirado, Delladira
    El estado de Tamaulipas, México, cuenta con una fauna de peces nativos típicamente de agua dulce que consiste de 20 familias, 5O géneros y 85 especies, de las cuales Neárticas-Primarias 23 géneros y 49 especie, Neárticas-Secundarias cinco géneros y ocho especies, Neotropicales-Primarias, un género y dos especies, Neotropica les-Secundarias siete géneros y 19 especies, Periféricas son nueve familias, doce géneros y 16 especies. La NOM 059-ECOL-2001 categoriza en Tamaulipas 19 especies (mas l que será propuesta) debidas a diversos impactos del desarrollo, siendo tres en peligro, once amenazadas, dos de protección especial, y tres probablemente extintas. Las especies introducidas pertenecen a cuatro familias, trece géneros, y 24 especies. Siete especies son nativas en el norte de Tamaulipas, y exóticas en el sur. Las causas de riesgo son especies exóticas, reducción de hábitat, contaminación, aguas residuales, basuras, lluvia ácida, erosión acuática y terrestre, ensalitramiento, abatimiento del nivel de agua y desecado de acuíferos, ríos, lagos; alteraciones de hábitat (represamiento, canalización, desecamiento de humedales, dragado, cortes carreteros); deforestación, y algunos fenómenos naturales, como sequía, incluyendo la reducción de población de algunas especies, naturalmente raras o localizadas. Un desarrollo no sustentable está matando los ecosistemas riverinos de Tamaulipas.
  • Item
    Biodviersityof Mexican Trout (Teleostei: Salmonidae: Oncorhynchus): Recent findings, conservation concerns, and management recommendations
    (Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Monterrey, Nuevo León, México, 2004-09) Mayden, Richard L.
    Until very recently the diversity of trout in Mexican rivers of the Sierra Madre Occidental has been very poorly understood and only the Rainbow Trout, Oncorhynchus mykiss, and the Mexican Golden Trout, 0. chrysogaster, have been recognized. Recent efforts in the last decade by a binational organization of scientists and laypersons interested in the diversity and conservation of Mexican trout, Truchas Mexicanus, have revea led considerable diversity within the river systems of the Pacific Slope south to the Rio Acaponeta . These trout forms are highly differentiated and distinctive, and are considered native to these high-elevation river systems in pine-dominated forests. The increased occurrence of trout growout facilities and hatcheries within the range of these native Oncorhynchus and the escapes from these facilities threaten the native trout diversity through both introgressive hybridization and through resource competition, end products already known to occur in other trout populations in the other areas of North America exposed to exotic hatchery trout. Other threats to the native and previously unknown trout biodiversity in Mexico include timber harvesting, some pollutions associated with these activities, and siltation of critical habitats. Recommendations are provided to aid in the safe management and protection of this diversity which center around the future use of sterile trout in growout facilities and the use of undisturbed buffer zones along streams. The divergence observed in forms of Mexican trout is equivalent to the levels of divergence found between currently recognized subspecies of trout in the Rainbow and Cutthroat trout groups. Upon review of the diversity and divergence known to exist in these groups and our current understanding of conceptualizations of species, it is argued that the recognition of subspecies within these highly diverse trout lineages is inconsistent with the natural evolutionary history of these groups. The long-term use of the Biological Species Concept for these species is argued as not only inappropriate but an inadequate and illogical characterization of diversity. The logical consequences of hanging on to this concept as the operational and theoretical framework of trout diversity would necessitate the synonymization of all Rainbow and Cutthroat trout taxa as subspecies because of the known propensity of these groups to demonstrate introgressive hybridzation in some areas. These subspecies are considered va lid evolutionary lineages that are demonstrate divergence at morphological, genetic, and ecological characters that are well known to many trout taxonomists and biologists. All of these therefore qualify as Evolutionary Species that are easily diagnosable under the Phylogenetic Species Concept and should be recognized as valid species.