Life Sciences Commons^™

First Nesting Records Of The Black Phoebe (Sayornis Nigricans) In Southernmost Texas, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.

Patterns Of Avian Productivity Indices At Santa Ana National Wildlife Refuge (1995–1999), Tina Louise Gallegos

Theses and Dissertations - UTB/UTPA

I examined demographic parameters at Santa Ana National Wildlife Refuge, 1995–1999 utilizing Monitoring Avian Productivity and Survivorship protocol. The Olive Sparrow was the species most frequently captured. The capture rate of adult and young birds remained fairly steady over the years and no significant linear trends were observed. Productivity was highest in 1997, which influenced the number of adults captured in 1998, and was significantly related to annual rainfall. Mean total capture rates were higher at the Highland station than the Resaca station. Demographic comparisons between mist nets and point counts were variable, suggesting that both sampling techniques have their …

Range Extensions Of The Seaweeds Codium Taylorii And Caulerpa Prolifera Into The Lower Laguna Madre, Texas, Hudson R. Deyoe, Donald L. Hockaday

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Between January 1999 and April 2000 two chlorophyte algae, Codium taylorii Silva and Caulerpa prolifera F. obovata (Forsskal) Lamouroux were found in the lower Laguna Madre (LLM). Both are coenocytic algae and are members of the chlorophyte class Bryopsidophyceae ( van den Hoek et al. 1995). The species descriptions in Taylor (1960) were used in the identification of the specimens. Her barium specimens have been deposited at the University of Texas- Pan American Coastal Studies Laboratory (accession numbers COlO - C. prolifera, COl 1 - C. taylorii) , University of California at Berkeley (UC 1753606 - C. taylorii) , University …

Detection Of The Phototoxic Dye Phloxine B In Anastrepha Ludens (Loew) (Diptera: Tephritidae), Apis Mellifera Linnaeus (Hymenoptera: Apidae) And Honey, Aleena M. Tarshis Moreno

Theses and Dissertations - UTB/UTPA

A spectrophotometric method for detection of phloxine B, a phototoxic dye proposed as a replacement for malathion bait sprays, in extracted tissues of Anastrepha ludens, Apis mellifera and in honey was developed. Dye detection was increased with a pH change from 6 to 13.7 in tissues or from 3.7 to 8 in honey with 2% sodium hydroxide. An LC 50 of 29.62 ppm phloxine B in 30% sucrose was obtained by feeding honey bees. A predictive model for dye in insect tissues and honey was developed and shown to be 89–92% effective. This study provides a forensic approach to determine …

Comparison Of Rodent Communities Of Native Brushland, Replanted, And Secondary Succession Sites In The Lower Rio Grande Valley Of Texas, Mitchell Allen Sternberg

Theses and Dissertations - UTB/UTPA

I compared small mammal communities between mature brushlands, replanted brushlands, and secondary succession sites from November 1998 to December 1999 to evaluate revegetation efforts in the Lower Rio Grande Valley of Texas. I determined rodent community characteristics of the three habitat types. The mature brushland and replanted habitats had similar species diversities and both were significantly higher than the secondary succession habitat. Species diversity was highest at the replanted edge grid during Winter. The current replanting method provides a more diverse rodent community than does natural succession from fallow fields. Wildlife monitoring should be extended to other taxonomic guilds so …

Productivity Estimation In Halodule Wrightii: Comparison Of Leaf-Clipping And Leaf-Marking Techniques, And The Importance Of Clip Height, Joseph L. Kowalski, Hudson R. Deyoe, Terry C. Allison, James E. Kaldy

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

We compared estimates of Halodule wrightii leaf growth rates obtained from leaf-clipping and leaf-piercing methods in a south Texas lagoon. Leaf clipping underestimated leaf production from 15 to 37% in winter and 25 to 60% in summer relative to leaf piercing. The underestimation of leaf-clipping derived growth rates were corrected using a linear regression between leaf growth rates determined by leaf-clipping and leaf-piercing methods. To examine the effect of clip height on H. wrightii leaf growth rate estimation, leaves were clipped at 0, 2, 4, 6, and 8 cm above the sediment. Leaves clipped at 2 cm exhibited the fastest …

Modeling Of A Meat Cooking Process For On-Line Monitoring And Control, Oralia Garcia

Theses and Dissertations - UTB/UTPA

A heat transfer model is developed to predict cooking time of meat patties given the initial temperature of meat, oven temperature, and meat properties to monitor and control a cooking process on-line. Experiments were performed to find the cause of variability in cooked weight and raw temperature effects in forming and final cooked temperature. Advanced charting techniques concluded that only common causes of variability were present in the process. Thermal conductivity experiments were performed to determine the thermal conductivity of meat (k), which was compared with the properties of meat published in literature to validate the experiment. Oven design analysis …

Comparative Phenology Of Acacia Berlandieri, A. Minuata, A. Rigidula, A. Schaffneri, And Chloroleucon Ebano In The Lower Rio Grande Valley Of Texas, Melissa R. Eddy

Theses and Dissertations - UTB/UTPA

A phenological study of Acacia berlandieri, A. minuata, A. rigidula, A. schaffneri, and Chloroleucon ebano was conducted at three sites in the lower Rio Grande Valley of Texas from July 1998 to August 1999. Flowering in Acacia species occurred between January and April 1999, and was influenced by precipitation only in A. minuata . The timing of flowering appears to be influenced by the amount of time needed for fruit maturation. Precipitation, photoperiod, and temperature influenced the timing of fruiting in all species except A. berlandieri . Shoot elongation and leaf maturation in Acacia species were positively correlated with …

World Birding Center-Edinburg: An Application To The Meadows Foundation, Wendy Smith Sturgis

Theses and Dissertations - UTB/UTPA

The World Birding Center is a unique and innovative partnership among Texas Parks & Wildlife Department and the cities of Brownsville, Mission, Weslaco, Harlingen, Edinburg, McAllen, Hidalgo, Roma, Rio Hondo and South Padre Island. The WBC is a first of its kind regional approach to nature conservation and birdwatching.

Edinburg's portion of the budget is 8.75%, and the City will fund salaries for a director and education coordinator and operations specific to the Edinburg center through the City's general fund.

Texas Parks & Wildlife Department estimates 175,000 visitors annually. Direct local expenditures (based on an average visit of 6.3 days, …

Factors Affecting Reproductive Success In Hosts Of The Bronzed Cowbird (Molothrus Aeneus) In The Lower Rio Grande Valley, Texas, Christopher R. Hathcock

Theses and Dissertations - UTB/UTPA

During 1997–99, brood parasitism by the Bronzed Cowbird ( Molothrus aeneus), nest predation, and nest sites were examined in selected songbird species in southern Texas. I found a significantly lower parasitism rate in the Long-billed Thrasher (Toxostoma longirostre ) and Olive Sparrow (Arremonops rufivirgatus) than did Carter (1984) at the same site in the early 1980's. High rates of cowbird visitation to Altamira Oriole (Icterus gularis) nests suggest that cowbirds frequently attempt to parasitize this species. However, orioles probably puncture-eject cowbird eggs from their nests most of the time. Orioles experienced a significantly lower …

Nesting Of Rose-Throated Becard Pachyramphus Aglaiae (Passeriformes: Incertae Sedis) And Clay-Colored Robin Turdus Grayi (Passeriformes: Turdidae) In Hidalgo County, Texas, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.

Detoxification Of 4-Nitroquinoline 1-Oxide And Benzo(A)Pyrene-4,5-Oxide By Myristicin Induced Glutathione S-Transferase In A/J Mouse Livers, Eduardo Saldivar

Theses and Dissertations - UTB/UTPA

The activities of mouse liver glutathione S-transferases (GSTs) induced by myristicin, the active compound in parsley leaf oil, against the carcinogens 4-nitroquinoline 1-oxide (4NQO) and benzo(a)pyrene-4,5-oxide (BP-4,5-oxide) were studied. A/J mice were treated with three 20 mg doses (one dose every other day) by gavage. Affinity purified liver GST samples from treated animals showed a 7.2-fold increase in activity toward 4NQO when compared with equal amounts of liver samples prepared from the control group. Activity against BP-4,5-oxide was increased 1.8-fold in the experimental group. Experimental samples also showed a significant increase in activity toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 2,4-dichloronitrobenzene (DCNB), …

Field Notes On The Biology Of The Long-Wattled Umbrellabird Cephalopterus Penduliger In West Ecuador., Karl S. Berg

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

La biología del Pajaro Paraguas Longipendulo Cephalopterus penduliger es quizas lo menos conocido del genero. A pesar de eso, lo consideraron una de las especies más amenzadas en el continente Sudamericano debido a la deforestación, caza y a un grado menor, la comercialización de las aves como mascotas. Entre febrero y octubre de 1998 yo observe C. penduliger a lo largo del período y 1.600 horas de observación en la Estación Biológica Jatun Sacha Bilsa, Provincia de Esmeraldas, Ecuador. Documente varios aspectos de las observaciones incluyendo un sonogramo de dos vocalizaciones, descripciones de comportamiento, forrageo y las primeras fotos de …

First Nesting Record Of Blue Jay (Cyanocitta Cristata) In Hidalgo County, Texas, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

No abstract provided.

Use Of Randomly Amplified Polymorphic Dna-Polymerase Chain Reaction (Rapd-Pcr) To Distinguish North American Populations Of Acroptilon Repens (L.) Dc, Raul A. Ruiz

Theses and Dissertations - UTB/UTPA

Sixty U.S. populations of Acroptilon repens collected in 1998 were analyzed using RAPD-PCR. Each population was represented by five specimens gathered from each location. A total of 301 specimens were examined using two Operon Technologies, RAPD-PCR primers (A 10 and C04). The DNA amplification products produced through the PCR process were electrophoretically separated to produce DNA fragments ranging from 100 to 2000 base-pairs in length. The 60 U.S. populations sampled, produce ten RAPD banding pattern types using A 10 primer and seventeen pattern types with C04. Genetic variation within and among the populations was low, however, one dendogram did show …

Production Of The Subtropical Seagrass, Halodule Wrightii Aschers., In Lower Laguna Madre, Texas, Joseph L. Kowalski

Theses and Dissertations - UTB/UTPA

The autecology of shoal grass, Halodule wrightii Aschers., was studied at 1.2 m depth from June 1995 to February 1997 in Lower Laguna Madre (LLM), Texas. Halodule wrightii in LLM received about 47% surface irradiance, but otherwise displayed lower growth rates and biomass in nutrient-poor rhizosphere and water-column environments compared to H. wrightii populations in other Texas estuaries. High tissue N content and low C:N ratios belied low growth dynamics. Halodule wrightii in LLM is probably nutrient limited. A high nutrient demand by H. wrightii in a nutrient-poor environment may explain, in part, its gradual displacement by Thalassia testudinum and …

Vegetative Change On South Padre Island, Texas, Over Twenty Years And Evaluation Of Multispectral Videography In Determining Vegetative Cover And Species Identity, Robert I. Lonard, Frank W. Judd, James H. Everitt, David E. Escobar, Mario A. Alaniz, Isabel Cavazos Iii, M. R. Davis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

A comparative vegetation analysis of an island-wide transect of South Padre Island, Texas, was conducted in 1997 using aerial multispectral digital videography and line intercept ground truth techniques to assess the usefulness of videography in estimating vegetative cover and species identifications. Ground truth data were used to assess vegetative change occurring in the 20 years since the report of Judd et al. (1977) on the vegetation of South Padre Island. Estimates of total cover by ground truth and remote sensing techniques were similar (2.45% difference) on South Padre Island. Thus, airborne multispectral digital videography is an effective technique for assessing …

The Biological Flora Of Coastal Dunes And Wetlands. Ipomoea Imperati (Vahl) Griseb., Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Beach morning glory, Ipomoea imperati (Vahl) Griseb. = I. stolonifera (Cirillo) Gmelin is a pantropical, prostrate vine that is an important pioneer species in the backshore of coastal beaches of six continents and many islands. The landward distribution of beach morning glory is influenced by dispersal and competition, and its seaward distribution is determined by the physical environment acting through movement of seeds away from the water and high seedling mortality in the backshore. It is occasionally found in disturbed sites on barrier islands well inland from the shore. Beach morning glory tolerates low levels of soil nutrients, sand scouring, …

Sucrose Metabolism In Two Saccharum Species, Monica Ida Valdez-Garza

Theses and Dissertations - UTB/UTPA

S. officinarum is a thick-stemmed sugarcane which stores large amounts of sucrose, and S. spontaneum is thin-stemmed with very little sucrose. Sucrose synthase (SS), sucrose phosphate synthase (SPS), and invertase enzymes are thought to affect the accumulation of sucrose in the stems of sugarcane. This study was performed to determine if (i) differences between SPS and acid invertase activities account for the difference in sucrose content of sugarcane stems, and (ii) differences in SS activity influence sucrose concentration. The difference between SPS and acid invertase activities did not appear related to the low sucrose content in S. spontaneum. However, the …

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 Ecology And Vocalisations Of Banded Ground-Cuckoo Neomorphus Radiolosus, Bernabé López-Lanús, Karl S. Berg, Ralf Strewe, Paul G. W. Salaman

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

El Cuco-Hormiguero Franjeado Neomorphus radiolosus es un ave rara, con problemas de conservación y cuya información sobre comportamiento y biología es deficiente. Cualquier dato adicional en este aspecto representa un instrumento importante para su conservación. Presentamos nuevos datos sobre su compartamiento en base a individuos observados en la Estación Biológica Jatun Sacha Bilsa, Esmeraldas, Ecuador, y la Reserva El Pangan, Nariño, Colombia.

Current Status Of Northern Beardless-Tyrannulet And Tropical Parula In Bentsen-Rio Grande Valley State Park And Santa Ana National Wildlife Refuge, Southern Texas, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

There are no published records of Northern Beardless-Tyrannulet (Camptostoma imberbe) and Tropical Parula (Parilla pitiayumi) nesting in the Lower Rio Grande Valley of Texas since the late 1940s. In this 1996- 1998 study, both species were confirmed nesting at Santa Ana National Wildlife Refuge, and Northern Beardless-Tyrannulet was also confirmed at Bentsen Rio Grande Valley State Park. Most Northern Beardless-Tyrannulet nests were between clumps of ball-moss (Tillandsia recurvata) in cedar elm (Ulmus crassifolia) trees, and nests were active from 21 March-23 September. Only fe. males build nests or incubate. Two-three young fledged per successful nest, but three nests were abandoned …

Changes In The Breeding Bird Community Of Subtropical Evergreen Forest In The Lower Rio Grande Valley Of Texas, 1970s-1990s, Timothy Brush, Alberto Cantu

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Breeding-bird censuses conducted in 1994-1996 at the Santa Ana National Wildlife, southern Texas were compared to those done on the same site in 1973-1978. The study site was described as subtropical evergreen forest in the 1970s, but is now thorn-forest with remnant evergreen forest. Canopy cover was incomplete and lower and trees were smaller and more densely packed in 1994-1996 than in 1973-1978. Seven bird species typical of thorn-forest and thorn-scrub, which were not present in 1973-1978, made up 20% of the breeding bird community in 1994-1996. Species tolerant of thorn-forest and thorn-scrub made up 76.0% of the breeding bird …

Effect Of Artificial Flooding On The Vegetation And Avifauna Of Riparian Woodlands At Santa Ana National Wildlife Refuge, Hidalgo County, Texas, Charles David Castillo

Theses and Dissertations - UTB/UTPA

Riparian habitats along the Rio Grande at Santa Ana National Wildlife Refuge have dramatically decreased since the construction of Falcon Dam in 1953. Riparian habitats are dependent on annual or periodic flooding to maintain their biological integrity. Lack of seasonal flooding has contributed to changes in vegetative composition from riparian forests to thornscrub. Effects of artificial flooding on vegetation and avifauna of riparian woodlands were evaluated from 1995-1997 at the Santa Ana National Wildlife Refuge. Floodwaters caused the destruction of all existing herbaceous species along study transects and the regeneration of new and native seedlings. Avian abundance and diversity dramatically …

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 …

Breeding Densities And Habitat Of Riparian Birds Along The Lower Rio Grande, Texas, Corinna Elizabeth Rupert

Theses and Dissertations - UTB/UTPA

The breeding biology of Snowy Plovers (Charadrius alexanderinus) was studied at Laguna Atascosa National Wildlife Refuge in coastal southern Texas. During 1995 and 1996 nests were found most often in high sand flat habitat and less frequently in low sand flat. Nest sites were dominated by open flat but had more rocks, pebbles and debris than control sites. Only 24% of the clutches hatched, while 67% were eaten by predators and 9% were flooded. Forty-three percent of Snowy Plover nests were within Least Tern (Sterna antillarum) colonies and these nests had a significantly greater chance of hatching than nests placed …

Habitat Selection, Population Density, And Home Range Of The Elf Owl, Micrathene Whitneyl, At Santa Ana National Wildlife Refuge, Texas, Christopher Michael Gamel

Theses and Dissertations - UTB/UTPA

The Elf Owl, Micrathene whitneyi, is a regular summer resident of the southwestern United States. My objectives were to collect information concerning habitat selection, home range size, and population density of M. w. idonea, the subspecies occurring in the Lower Rio Grande Valley of Texas. Nocturnal surveys indicated greater use of chaparral habitat (92%) compared to riparian woodlands (8%). Utilized habitat was characterized by highest foliage density at 2.5-3.0 m, with a partial canopy at 3.8 $\pm$ 0.36 m and a semi-open understory. Home range size ranged from 0.24 to 2.6 ha, with a mean of 1.05 $\pm$ 0.33 ha. …

Homology Among The Autosomal Chromosomes Of Boophilus Annulatus (Say) And B. Microplus (Canestrini), Bonnie S. Gunn

Theses and Dissertations - UTB/UTPA

Autosomes of Boophilus annulatus and B. microplus were compared using C- and G-bands to establish the degree of homology. Karyotypes of both species consisted of 20 autosomes and an XX:XO sex determination system with the X being the largest chromosome. All chromosomes of B. annulatus were acrocentric with heterochromatin limited to centromeric regions. The B. microplus karyotype was acrocentric with one band of noncentromeric heterochromatin occurring in three chromosome pairs. Interspecific comparisons indicated seven pairs of G-band homologous autosomes and three G-band homologous pairs when added interstitial heterochromatin was considered. The number three chromosome of both species showed variation in …

Aquatic Macroinvertebrates Of Rio Grande Delta Ponds, Anna Maria Navarro

Theses and Dissertations - UTB/UTPA

The purpose of this study was to identify aquatic macroinvertebrates living in the vegetated margins of local ponds, to determine their relative abundances, and to construct a rapid bioassessment model. I collected macroinvertebrates seasonally from seven ponds in the Lower Rio Grande Valley. Collection sites included: Moore Airfield, Santa Ana National Wildlife Refuge, and Olmito Fish Hatchery. Twenty-eight samples were sampled and preserved at the University of Texas-Pan American. Seventy-six taxa were identified and were stored as a reference collection. Cluster analysis of the taxa and their relative abundances showed three distinct geographic patterns or regions. These patterns were verified …

Habitat Use And Activities Of The Piping Plover, Charadrius Melodus, Wintering On South Padre Island, Texas, Humberto Garza Jr.

Theses and Dissertations - UTB/UTPA

The Piping Plover, Charadrius melodus, is endangered in its breeding sites and threatened in its wintering sites. This migratory shorebird spends 3 to 4 months on northern U.S. and southern Canadian breeding sites and the remainder of the year in Gulf of Mexico, Caribbean, and southern U.S. wintering sites. Up to 2.4% of the estimated Piping Plover population remains for the 9 to 10 month non-breeding season on South Padre Island (S.P.I.). During the non-breeding season, I conducted censuses at 15 sites in the southern portion of South Padre Island to determine Piping Plover habitat preferences. Piping Plovers prefer bay …