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Full-Text Articles in Biology

Social Influences On Vocal Development In A Wild Parrot, Caleb Michael Mand Arellano May 2019

Social Influences On Vocal Development In A Wild Parrot, Caleb Michael Mand Arellano

Theses and Dissertations

The Social Intelligence Hypothesis (SIH) proposes that navigating complex societies requires increased neural processing to monitor shifting relationships. SIH evolutionary focus of brain size variation in adults originally ignored the developmental frameworks leading to increased sociality. I studied the ontogeny of early sibling interactions in wild Green‐rumped Parrotlets (Forpus passerinus) in a Venezuelan population that exhibited large variation in brood size and engaged in elaborate social interactions and complex social learning during nestling development. To test if nests of varying brood sizes exhibit differences in social complexity, I quantified the number and strength of sibling play partnerships, as a proxy …


A Phylogenetic Analysis Of Leptogorgia Virgulata And Leptogorgia Hebes In The Northwestern Gulf Of Mexico, Samantha Silvestri Dec 2018

A Phylogenetic Analysis Of Leptogorgia Virgulata And Leptogorgia Hebes In The Northwestern Gulf Of Mexico, Samantha Silvestri

Theses and Dissertations

The use of genetics in recent years has brought to light the need to reevaluate the classification of many gorgonian octocorals. In 2017, Poliseno et al. conducted a comprehensive, phylogenetic study of the genus Leptogorgia and found that it, too, was in need of taxonomic revision. To expand on their study, 25 samples representing two Leptogorgia species—L virgulata and L. hebes —from the northwestern Gulf of Mexico (GOM) were examined. Ten novel, complete mitochondrial genomes were sequenced using Next Generation sequencing and 24 novel mtMutS sequences were obtained from both species. The phylogenies reconstructed from these sequences indicate the …


Effects Of Invasive Nilgai Antelope (Boselaphus Tragocamelus ) Browsing On Black Mangrove (Avicennia Germinans) In South Texas: A Study On Microenvironmental, Physiological, Structural, And Reproductive Parameters, Tianna Picquet Dec 2018

Effects Of Invasive Nilgai Antelope (Boselaphus Tragocamelus ) Browsing On Black Mangrove (Avicennia Germinans) In South Texas: A Study On Microenvironmental, Physiological, Structural, And Reproductive Parameters, Tianna Picquet

Theses and Dissertations

Mangroves are important for coastal systems because they provide habitat for fish and bird species, mitigate erosion, and create an area for carbon sequestration. Along the Gulf of Mexico, at the southern tip of Texas, recent observations have shown that A. germinans stands (the dominant species in Texas) are being browsed on by invasive nilgai antelope (Boselaphus tragocamelus). The antelope were introduce to the south Texas region via King Ranch in the 1930’s and have since significantly increased in population and distribution. Previously thought to be grazers, B. tragocamelus were captured on camera utilizing A. germinans as a …


Questing Activity Of Cattle Fever Tick Larvae, Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae): Environmental Influences And Implications For Control In South Texas, Brenda Leal Aug 2018

Questing Activity Of Cattle Fever Tick Larvae, Rhipicephalus (Boophilus) Microplus (Acari: Ixodidae): Environmental Influences And Implications For Control In South Texas, Brenda Leal

Theses and Dissertations

Questing ticks ascend stems, leaves, or rocks, extend their front legs, and wait poised for attachment to a passing host. Ixodid ticks have four developmental stages. Because ticks detach and molt between stages most ticks require three separate hosts to complete their lifecycle. Three-host ticks quest for a new host between each stage, whereas a few specialist tick species remain on and thus require only a single host. These one-host ticks only quest for hosts as larvae. As much as 90% of the life cycle may consist of questing when hosts are scarce. Most of the literature on questing relates …


Utilizing Accelerometer Telemetry Tags To Compare Red Snapper (Lutjanus Campechanus) Behavior On Artificial And Natural Reefs, Ethan T. Getz Dec 2017

Utilizing Accelerometer Telemetry Tags To Compare Red Snapper (Lutjanus Campechanus) Behavior On Artificial And Natural Reefs, Ethan T. Getz

Theses and Dissertations

The Texas Parks and Wildlife Department Artificial Reef Program has deployed over 2,800 hectares of reefing area composed of petroleum platforms, steel vessels, and concrete. Artificial reefs have been shown to support many important reef fishes such as red snapper (Lutjanus campechanus), however, few studies have compared fish behavior on artificial reefs and natural habitats. We examined activity levels, behavioral patterns and habitat preferences of red snapper over natural reefs, oil platforms and submerged ships. Telemetry tags (Sonotronics model MTT) with tri-axial acceleration range, average depth, and average temperature were programmed to optimize data collection and tag life. …


Genetic Diversity Of Kemp's Ridley (Lepidochelys Kempii) Sea Turtles On South Padre Island, Texas, Hilary R. Frandsen Dec 2017

Genetic Diversity Of Kemp's Ridley (Lepidochelys Kempii) Sea Turtles On South Padre Island, Texas, Hilary R. Frandsen

Theses and Dissertations

In 2010, researchers observed an abrupt decline in nesting numbers of the Kemp’s ridley following 35 years of positive growth. In wake of this halt, and subsequent lowered nesting averages, evaluation of the genetic diversity of remaining individuals is relevant to investigate the plausibility of a genetic bottleneck, and determine the reproductive stability of the Kemp’s ridley.

Here, I evaluate the genetic diversity within a sampling of the Kemp’s ridleys on South Padre Island using two methods: targeting the mitochondrial control region and targeting the complete mitochondrial genome. Opportunistic samples were donated from juvenile ridleys on the East coast, and …


The Vocal Babbling Behavior And Its Sibling Effects In A Wild Parrot, Tatiana Dolgushina May 2017

The Vocal Babbling Behavior And Its Sibling Effects In A Wild Parrot, Tatiana Dolgushina

Theses and Dissertations

Vocal learning is a rare trait in the animal kingdom, defined as the sensorimotor imitation of sounds, and is only found in select groups of birds and mammals. Parrots are a behaviorally complex group of birds, famous for their ability to mimic social companions, but how they develop this ability in the wild has received little attention. The vocal learning period consists of a complex vocal babbling stage, a crucial developmental precursor for imitation of adult vocalizations in humans and songbirds, but has not been described in any of the 360+ parrot species. This project quantifies potential individual variation in …


The Impact Of Sleep Disruption On Mouse Physiology, Behavior, And Welfare, Amanda L. Robinson-Junker Dec 2016

The Impact Of Sleep Disruption On Mouse Physiology, Behavior, And Welfare, Amanda L. Robinson-Junker

Open Access Theses

Laboratory mice are nocturnal, spending most of their daylight hours asleep. But they live in the diurnal world of human investigators and husbandry staff, who primarily work during this rest period. In humans, lack of sleep or sleep that occurs outside the normal circadian sleep period (as in shift work) has adverse effects. These include increased risk of cardiovascular disease, cancer, metabolic disorder, mood disorders, type II diabetes, and obesity. However, it is unknown if mice experience sleep disruption due to these human activities, and, if so, what the adverse effects may be. This is an important question, not only …


The Role Of Hif1alpha And Hif2alpha In Muscle Development And Satellite Cell Function, Shiqi Yang Dec 2016

The Role Of Hif1alpha And Hif2alpha In Muscle Development And Satellite Cell Function, Shiqi Yang

Open Access Theses

Hypoxia inducible factors (HIFs) are central mediators of cellular responses to fluctuations of oxygen, an environmental regulator of stem cell activity. Muscle satellite cells are myogenic stem cells whose quiescence, activation, self-renewal and differentiation are influenced by microenvironment oxygen levels. However, the in vivo roles of HIFs in quiescent satellite cells and activated satellite cells (myoblasts) are poorly understood. Expression analyses indicate that HIF1α and HIF2α are preferentially expressed in pre- and post-differentiation myoblasts, respectively. Interestingly, double knockout of HIF1α and HIF2α (HIF1α/2α dKO) in embryonic myoblasts results in apparently normal muscle development and growth. However, HIF1α/2α dKO in postnatal …


Avian Communities In An Urbanizing Region: Abundance Patterns And Effects Of Local Habitat Features, John S. Brush Dec 2016

Avian Communities In An Urbanizing Region: Abundance Patterns And Effects Of Local Habitat Features, John S. Brush

Theses and Dissertations

The Lower Rio Grande Valley of Texas has experience rapid population growth and increase of urban area since the mid-20th century. The goal of this thesis were to: 1) explore patterns of avian communities in suburban and remnant urban woodlands, with particular interest in native forest species, and 2) to assess how local habitat variables, such as number of native trees, affect avian communities in suburban habitats, and 3) provide recommendations to municipalities and homeowners to enhance urban habitats for birds. Results indicated that remnant urban woodlands provided habitat for common native forest bird species that otherwise avoided suburban habitats, …


Relationships Between Texas Tortoise Carapace Length, Home Range Size, And Habitat Selection At Sites With Invasive Grass, Kiley V. Briggs May 2016

Relationships Between Texas Tortoise Carapace Length, Home Range Size, And Habitat Selection At Sites With Invasive Grass, Kiley V. Briggs

Theses and Dissertations

Invasive grasses in south Texas have the potential to negatively impact the threatened Texas tortoise (Gopherus berlandieri) by reducing the availability of preferred foods (forbs) and may cause tortoises to travel farther, lead to reduced carapace length, and reduce the availability of refugia from heat stress. I used compositional analysis, regression, and ANOVA to explore relationships between invasive grasses and habitat use, home range size, and carapace length, as well as compared daily maximum temperatures between tussocks of an invasive and native grass. Forbs were ranked higher in use over invasive grasses in compositional analysis, but not strongly so (p …


Comparing Reproductive Capacity Of Nearshore And Offshore Red Snapper, Lutjanus Campechanus, On Artificial Reefs In The Western Gulf Of Mexico, Ricky J. Alexander Dec 2015

Comparing Reproductive Capacity Of Nearshore And Offshore Red Snapper, Lutjanus Campechanus, On Artificial Reefs In The Western Gulf Of Mexico, Ricky J. Alexander

Theses and Dissertations

Red snapper collected quarterly from four artificial reefs in south Texas were examined to compare total length, total weight, age, and the proportion of male to female red snapper, calculate gonadosomatic index values, batch fecundity, annual spawning frequency, and annual fecundity, and estimate size and age at maturity. Spawning occurred from April to September, with most active spawning observed in June (58%). Despite larger red snapper producing more eggs, and fish being larger offshore, most active spawning (68%) and egg production (74%) was observed nearshore. Female red snapper reached 50% maturity (L50) between 350-550 mm, and L75 by 600 mm. …


Differential Gene Expression Between Two Developmental Stages Of The Gené'S Organ In The Cattle Fever Tick, Rhipicephalus (Boophilus) Microplus, Jason P. Tidwell May 2015

Differential Gene Expression Between Two Developmental Stages Of The Gené'S Organ In The Cattle Fever Tick, Rhipicephalus (Boophilus) Microplus, Jason P. Tidwell

Theses and Dissertations - UTB/UTPA

The southern cattle fever tick (SCFT), Rhipicephalus microplus, is considered the most economically important ectoparasite of livestock worldwide and ranks sixth among the most pesticide resistant arthropods globally. This single-host hard tick is a vector of the infectious agents causing bovine babesiosis and anaplasmosis. The estimated impact of these SCFT-borne diseases on the livestock industry in the world is $7 billion annually. This project focuses on the Gené’s organ and addresses the need to identify novel targets that can serve as the basis for sustainable SCFT control strategies. Wax secreted by the Gené’s organ protects tick eggs from desiccation, bacterial …


Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green Dec 2013

Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green

Graduate Theses and Dissertations

Dramatic range-wide declines in Greater Sage-Grouse populations have prompted efforts to determine habitat characteristics that are selected by sage-grouse for foraging, nesting and brood-rearing areas in an effort to conserve this species. Managers at Heart Mountain and Y U Bench in northwestern Wyoming expressed the need to quantify various habitat characteristics and to determine key use areas at both study sites. Data were collected on a variety of habitat variables in spots selected by grouse for foraging, nesting, and brood-rearing activities. These variables were compared to the same variables measured at random points at both study sites. Significant differences existed …


Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez Dec 2013

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez

Theses and Dissertations - UTB/UTPA

This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …


A Bird In The Binoculars: Understanding Birdwatchers' Potential To Contribute To Sustainable Development And Biological Conservation, Sheri Lynn Glowinski May 2013

A Bird In The Binoculars: Understanding Birdwatchers' Potential To Contribute To Sustainable Development And Biological Conservation, Sheri Lynn Glowinski

Dissertations

The three studies comprising this research drew from local economic development and environmental sociology to understand aspects of human dynamics that influence the conservation of birds. Using survey data collected from birdwatchers visiting coastal Alabama, the first study examined the local economic impact of birdwatching tourism and the factors that participants deemed important with respect to their recreation. Birdwatchers spent $103,305 during the four month study period. The total annual economic impact of this recreation on the area was estimated at $937,470, producing a multiplier of 1.48 and the equivalent of 20.3 full time jobs. Infrastructural variables (parking, bathrooms, site …


Interrelationships Between Testosterone, Aggression, And Parental Care Of A Temperate-Zone, Resident Songbird, The Northern Cardinal (Cardinalis Cardinalis), Margaret Susan Devries May 2013

Interrelationships Between Testosterone, Aggression, And Parental Care Of A Temperate-Zone, Resident Songbird, The Northern Cardinal (Cardinalis Cardinalis), Margaret Susan Devries

Dissertations

Interrelationships among testosterone (T), aggression, and parental care have received much investigative attention. Within birds, many studies have focused on examining such relationships using species characterized by relatively brief periods of territoriality and breeding. Few have investigated links between circulating T and reproductive behavior in birds that are year-round territorial residents and have lengthy breeding seasons, such as the Northern Cardinal (Cardinalis cardinalis). The following six chapters report and discuss findings from this dissertation’s examination of aspects of T production and potential interconnections with circulating T, aggression, and parental care in male and female cardinals. This work suggests …


Responses To Predator Recognition Odors In Marmorkrebs, Loren Samantha Beard Aug 2012

Responses To Predator Recognition Odors In Marmorkrebs, Loren Samantha Beard

Theses and Dissertations - UTB/UTPA

Marmorkrebs is a parthenogenetic crayfish with no indigenous populations. They have been introduced in several countries and could become an invasive species. Individuals introduced in Germany had longer, sharper spines, suggesting an adaptation to predators via developmental plasticity. This was tested by exposing juveniles to the odor of a fish during development and comparing them to controls. Subsequent spine length or sharpness did not differ. Other crayfish detect predators via an alarm cue, hemolymph, and exhibit avoidant behavior in response. I hypothesized that Marmorkrebs would also treat hemolymph as an alarm cue. The behavior of adult crayfish exposed to food, …


Movement Ecology Of An Intercontinental Migratory Bird During Spring Stopover, Emily Beth Cohen Dec 2011

Movement Ecology Of An Intercontinental Migratory Bird During Spring Stopover, Emily Beth Cohen

Dissertations

Movement ecology is a component of nearly all aspects of animal behavior and an animal’s decision to move is likely influenced by a complex combination of exogenous and endogenous factors. Therefore, an examination of the causes and consequences of organismal movement provides a conceptual framework for understanding complex behavioral strategies. My dissertation research is focused on the movement ecology of an intercontinental migratory songbird during spring migration. I adopted experimental approaches to study the factors influencing how a songbird migrant, red-eyed vireos (Vireo olivaceus), makes decisions in unfamiliar landscapes from the initiation of spring stopover.

I simulated the …


The Study Of The Parasitic Fauna In Sciaenops Ocellatus, Lower Laguna Madre, Texas, Veronica Abrigo Dec 2011

The Study Of The Parasitic Fauna In Sciaenops Ocellatus, Lower Laguna Madre, Texas, Veronica Abrigo

Theses and Dissertations - UTB/UTPA

Parasitological investigations provide information on ecosystem health because parasite prevalence and abundance are influenced by biotic and abiotic environmental changes. This survey classified the parasitic fauna of red drum, Sciaenops ocellatus, in the Lower Laguna Madre, TX. Fish (n = 239) were collected from four study sites (May 2005 - June 2006). Parasite identification consisted of digenean and monogenean trematodes, cestodes, larval nematodes, copepods, and protozoans. Parasite prevalence and host length was positively correlated from South Bay (r=0.473), Port Isabel (r=0.533), Arroyo(r=0.314), and Port Mansfield (r=0.630). Significant differences (p<0.001) between zone and parasite prevalence from Arroyo site indicated a higher prevalence of protozoa and monogeneans and reduced prevalence of digeneans. Statistical analyses indicated the greatest difference between Port Isabel and Arroyo sites ( divided by 2= 48.195; p<0.001; df= 14), and the least difference between South Bay and Arroyo sites ( divided by 2= 20.847; p= 1.06; df= 14).


The Relations Among Laterality, Cortisol, And Approach-Avoidance Behavior In Garnett's Bushbaby (Otolemur Garnettii), David Burton Hanbury Aug 2011

The Relations Among Laterality, Cortisol, And Approach-Avoidance Behavior In Garnett's Bushbaby (Otolemur Garnettii), David Burton Hanbury

Dissertations

Many studies to date have demonstrated that approach and avoidance behaviors are processed asymmetrically in the brain and may be reflected in measures such as handedness. The purpose of this study was to extend work in primates on this topic to Garnett’s bushbaby, a prosimian species. Furthermore, to determine whether measures in addition to handedness relate to approach-avoidance behavior, lateralized differences in tympanic membrane temperature were assessed. Cortisol measures were also obtained to determine whether it was related approach-avoidance behavior and handedness. Eleven captive-born Garnett’s bushbabies (Otolemur garnettii) were evaluated for handedness and responsiveness to novelty. Moreover, the …


Life History And Habitat Use Of The Juvenile Alabama Shad (Alosa Alabamae) In Northern Gulf Of Mexico Rivers, Paul Fraser Mickle Dec 2010

Life History And Habitat Use Of The Juvenile Alabama Shad (Alosa Alabamae) In Northern Gulf Of Mexico Rivers, Paul Fraser Mickle

Dissertations

The Alabama shad, Alosa alabamae, is an anadromous species that is in decline and has seen extirpations from impoundments as well as decreased water quality. Alabama shad live in the Gulf of Mexico and ascend Northern Gulf of Mexico Drainages to reproduce early in the year (January-May). The juveniles spend the majority of the year in these freshwater systems before emigrating out to the Gulf of Mexico as late as December.

This dissertation focuses on the juvenile life stages that occur within the Northern Gulf of Mexico drainages. Spawning conditions of the river, as well as the habitat and diet, …


Bronzed Cowbird (Molothrus Aeneus) Habitat Use And Differential Response To Playback Of Host Song, Mary Jennifer Gorton May 2010

Bronzed Cowbird (Molothrus Aeneus) Habitat Use And Differential Response To Playback Of Host Song, Mary Jennifer Gorton

Theses and Dissertations - UTB/UTPA

During the breeding seasons of 2008 - 2009, 180 fixed-radius point-count surveys and broadcasts of host song were conducted in Santa Ana (SANWR) and Laguna Atascosa (LANWR, 2009 only) National Wildlife Refuges to identify Bronzed Cowbird (Molothrus aeneus) habitat use and test the predictions of the host activity hypothesis. Surveys demonstrated that Bronzed Cowbirds were distributed across all habitat types in both refuges, although there were differences in abundance between the sexes for interior and edge habitats and between habitat types. Bronzed Cowbirds responded differentially to host species playbacks based on suitability and abundance of the host species. The results …


Stress Responses To Salinity In A Native Fresh Water Snake (Nerodia Rhombifer), Joana A. Cordoba May 2009

Stress Responses To Salinity In A Native Fresh Water Snake (Nerodia Rhombifer), Joana A. Cordoba

Theses and Dissertations - UTB/UTPA

Salinity stress at 0 ppt, 9 ppt, 18 ppt, and 27 ppt was investigated in Nerodia rhombifer, a fresh water snake. The purpose of this study was to establish if exposure to salinity could elicit a hormonal response in the form of corticosterone. Salinity treatment 27 ppt was lethal for 50% of the snakes. Factors such as population and gender differences were not significant, p=0.748 and p=0.135, respectively. Exposure to the different salinities did not significantly affect the overall mass of the animal, p=0.951. A significant increase in circulating corticosterone was noted in salinity treatments 0 ppt and 18 ppt, …


Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk Dec 2003

Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk

Theses and Dissertations - UTB/UTPA

Audubon's Oriole ( Icterus graduacauda ) was known historically throughout the Lower Rio Grande Valley (LRGV) of Texas, but its breeding range has now declined to mainly riparian habitat in Starr County. Habitat loss, degradation, and fragmentation, and brood parasitism by Bronzed Cowbirds ( Molothrus aeneus ) are likely causes of this decline. Habitat patches where Audubon's Orioles were present were larger, with a larger vertical range of canopy, greater vegetation volume, greater richness of bird and woody plant species, less local deforestation, and less local habitat fragmentation than where Audubon's Orioles were absent. Bronzed Cowbirds showed no numeric correlation …


The Ecology And Life History Of The Mexican Tetra, Astyanax Mexicanus, (Teleostei: Characidae) In The Lower Rio Grande Valley, Texas, Mario Estrada May 1999

The Ecology And Life History Of The Mexican Tetra, Astyanax Mexicanus, (Teleostei: Characidae) In The Lower Rio Grande Valley, Texas, Mario Estrada

Theses and Dissertations - UTB/UTPA

The Mexican tetra has been found to migrate from shallow waters in the spring and summer months into deeper waters during the winter months when temperatures are too cold for their survival. This fish is omnivorous with insect material being the major source of food. Its food types include green algae, nematoceran larvae, hemipterans, coleopterans, hymenopterans, dipterans, ostracods, fish eggs and amphipods. Furthermore, size classes showed that the Mexican tetras reached their largest size at the River site and smaller sizes at the Bridge and Gate sites and apparently breed year round. They are capable of producing from 300 to …


The Brood-Rearing Habitat, Brood Home Range, And Fecundity Of The Snowy Plover (Charadrius Alexandrinus) In Coastal Southern Texas, Jeffery R. Rupert Dec 1997

The Brood-Rearing Habitat, Brood Home Range, And Fecundity Of The Snowy Plover (Charadrius Alexandrinus) In Coastal Southern Texas, Jeffery R. Rupert

Theses and Dissertations - UTB/UTPA

Habitat fragmentation has been shown to have negative effects on avian communities. I looked at the effects of corridor width and vegetation characteristics on nesting densities and breeding success of birds in the Lower Rio Grande Valley. There were definite trends in this study of increasing species richness and nesting densities with increasing corridor widths. Multiple regression revealed little correlation between tree density, diameter at breast height, tree height, canopy cover and ground cover with nesting density or nesting success. However, factors such as parasitism by the Bronzed Cowbird (Molothrus aeneus) and predation were much greater in narrower corridors. This …


Seasonal Distribution Of The Ichthyofauna Of Santa Ana National Wildlife Refuge, Alamo, Texas, Matthew Albert Ciomperlik Jan 1989

Seasonal Distribution Of The Ichthyofauna Of Santa Ana National Wildlife Refuge, Alamo, Texas, Matthew Albert Ciomperlik

Theses and Dissertations - UTB/UTPA

This study investigated the small aquatic ecosystems of Santa Ana National Wildlife Refuge, located in a predominantly agricultural area of the Lower Rio Grande Valley, Texas. Fishes and water quality data were collected for 13 months to determine the status of fish populations and the factors which influence their distributions on the refuge.

Sixteen fish species were collected during the study, however, more than 20 species are known to inhabit the Rio Grande in the vicinity of the refuge. Water source played a major role in influencing fish species richness in these aquatic ecosystems. Diverted river water offered the best …


Adaptation Of Striped Bass To Sea Water Following Direct Transfer From Freshwater: Morphological, Biochemical, And Physiological Parameters, Judy A. King May 1987

Adaptation Of Striped Bass To Sea Water Following Direct Transfer From Freshwater: Morphological, Biochemical, And Physiological Parameters, Judy A. King

Electronic Theses and Dissertations

There has been heightened interest in the biology of striped bass (Morone saxatilis) because of increased pollution in their native spawning grounds and because of their extensive use in landlocked sport fisheries. Their euryhalinity makes them an excellent species for osmoregulation studies. The objective of this research was to study the rate of adaptation of striped bass gills to sea water (3% salt) after direct transfer from freshwater using biochemical (ion transport enzyme levels), physiological (chloride efflux), and ultrastructural methods. Striped bass have specialized osmoregulatory cells located on the interlamellar and afferent surfaces of their gill filaments as shown by …


Eye Movement Related Single-Unit Recording In The Nucleus Reticularis Tegmenti Pontis In The Alert Monkey, William Franklin Crandall Jr. Jan 1981

Eye Movement Related Single-Unit Recording In The Nucleus Reticularis Tegmenti Pontis In The Alert Monkey, William Franklin Crandall Jr.

University of the Pacific Theses and Dissertations

Nucleus Reticularis Tegmenti Pontis (NRTP) is a structure which lies in the mid-brain ventral to the oculomotor complex. Anatomical studies strongly implicate it in oculomotor function as most of its inputs and outputs are to systems previously shown to be intimately involved in eye movement generation--superior colliculus (SC) and cerebellum. These reports show an integrative structure with inputs and outputs distributed in a way well suited for performing relay and feedback tasks. Physiological data in the alert, trained monkey has been gathered in an attempt to characterize these neurons and to classify them in functional terms. Three monkeys were trained …