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Full-Text Articles in Life Sciences
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 …
Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora
Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora
Theses and Dissertations - UTB/UTPA
Nerodia rhombifer is a polytypic, semi-aquatic snake with a broad geographical distribution ranging from the American Midwest southward to Chiapas, Mexico. Although relatively abundant throughout much of its range, few ecological studies of the species have been conducted. This study provides basic population ecology information in a subtropical habitat. Population data were obtained in a mark-recapture study at Santa Ana National Wildlife Refuge, Hidalgo County, Texas, from August 1995 to December 1998. Specimens taken elsewhere in Hidalgo County provided information on the reproductive biology. This study provides the first absolute density estimates from anywhere within the species’ range. Quantitative information …
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 …
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. …
Using The Spot-Mapping Censusing Technique To Assess Changes In Breeding Bird Communities At Santa Ana National Wildlife Refuge, Alamo, Texas, 1940-1996, Alberto Cantu
Theses and Dissertations - UTB/UTPA
Results of breeding-bird censuses done by Davis in 1940 and by Gehlbach between 1973-1978 at Santa Ana National Wildlife, Alamo Texas, were compared to a 1995-1996 bird survey done in Gehlbach's study area. According to the Wilcoxon rank-sum test, bird densities in 1940 and 1995-1996 were similar, while 1973-1978 densities were lower. The 1995-1996 bird community was 76% similar to both the earlier studies. However, the communities studied in 1940 and 1973-1978 had only a 60% similarity. Negligible differences in bird densities and species composition were found between the 1995 and 1996 communities. Differences are attributed to changes in vegetation …
A Comparison Of Secondary Successional Woody Vegetation In Two Revegetated Fields In South Texas And An Assessment Of Habitat Use By The Olive Sparrow, Arremonops Rufivirgatus, Patrick Grant Wright
A Comparison Of Secondary Successional Woody Vegetation In Two Revegetated Fields In South Texas And An Assessment Of Habitat Use By The Olive Sparrow, Arremonops Rufivirgatus, Patrick Grant Wright
Theses and Dissertations - UTB/UTPA
Aspects of plant species composition and structure of two revegetated fields in western Cameron County, Texas, were studied between 1992 and 1995. Avian habitat suitability was assessed using the Olive Sparrow, Arremonops rufivirgatus, as an indicator species. Total vegetation volume at the Longoria Wildlife Management Area (WMA), an area revegetated in 1961, was 0.745 $\rm m\sp3V/m\sp2$ and that of the Anacua WMA, revegetated in 1983-4, was 0.546 $\rm m\sp3V/m\sp2$ in 1992. Secondary woody species at the Longoria and Anacua WMA's had a Shannon's index of diversity of 0.619 and 0.264, respectively. Secondary woody vegetation at the Longoria WMA had a …