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Full-Text Articles in Life Sciences
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 …
The Brood-Rearing Habitat, Brood Home Range, And Fecundity Of The Snowy Plover (Charadrius Alexandrinus) In Coastal Southern Texas, Jeffery R. Rupert
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 …
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. …
Aquatic Macroinvertebrates Of Rio Grande Delta Ponds, Anna Maria Navarro
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.
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 …