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Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez
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 …
Comparative Pollen Foraging Of Africanized And European Honeybees In A Non-Agricultural Environment, Ruben Ruiz
Comparative Pollen Foraging Of Africanized And European Honeybees In A Non-Agricultural Environment, Ruben Ruiz
Theses and Dissertations - UTB/UTPA
With the advent of the Africanized honeybee, ways to differentiate it from the European honeybee have been greatly sought in attempts to better understand the role of Africanized bees in pollination. Pollen collecting strategies for both honeybee subspecies have been explored in attempts to exploit their pollinating capabilities. This project examined pollen collected by honeybees from feral and managed European and Africanized colonies in a relatively isolated site. Paired European and Africanized honeybee colonies were used to obtain pollen foragers. Through acetolysis (series acidified Acetic Anhydride washings); the collected pollen from the individual foragers was treated and observed with light …
Breeding Distribution And Habitat Use Of Audubon's Oriole In The Lower Rio Grande Valley Of Texas, Steven Gerald Monk
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 …
Patterns Of Avian Productivity Indices At Santa Ana National Wildlife Refuge (1995–1999), Tina Louise Gallegos
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 …
Comparison Of Rodent Communities Of Native Brushland, Replanted, And Secondary Succession Sites In The Lower Rio Grande Valley Of Texas, Mitchell Allen Sternberg
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 …
Factors Affecting Reproductive Success In Hosts Of The Bronzed Cowbird (Molothrus Aeneus) In The Lower Rio Grande Valley, Texas, Christopher R. Hathcock
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 …
The Ecology And Life History Of The Mexican Tetra, Astyanax Mexicanus, (Teleostei: Characidae) In The Lower Rio Grande Valley, Texas, Mario Estrada
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 …
Breeding Densities And Habitat Of Riparian Birds Along The Lower Rio Grande, Texas, Corinna Elizabeth Rupert
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 …
Effect Of Artificial Flooding On The Vegetation And Avifauna Of Riparian Woodlands At Santa Ana National Wildlife Refuge, Hidalgo County, Texas, Charles David Castillo
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 …
Habitat Selection, Population Density, And Home Range Of The Elf Owl, Micrathene Whitneyl, At Santa Ana National Wildlife Refuge, Texas, Christopher Michael Gamel
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. …
Habitat Use And Activities Of The Piping Plover, Charadrius Melodus, Wintering On South Padre Island, Texas, Humberto Garza Jr.
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 …
Feeding And Nesting Ecology Of The Great Kiskadee, Pitangus Sulphuratus Texanus (Passeriformes: Tyrannidae) In The Lower Rio Grande Valley, Texas, Robert Luis Gorena
Feeding And Nesting Ecology Of The Great Kiskadee, Pitangus Sulphuratus Texanus (Passeriformes: Tyrannidae) In The Lower Rio Grande Valley, Texas, Robert Luis Gorena
Theses and Dissertations - UTB/UTPA
The foraging and nesting ecology of the Great Kiskadee was studied in the Lower Rio Grande Valley, Texas during 1994 and 1995. Adult kiskadees were found to be omnivorous, feeding mainly on fleshy fruits, fish, and dragonflies, and capturing animal prey mainly by surface gleaning into water or hawking prey out of midair. Nests are constructed mainly during March and April and are built at heights between 6 and 10 meters apparently without preference to tree species. Of 29 nests observed, 66% (19) were active during at least part of the breeding season. Nestlings are fed a diet very similar …