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Full-Text Articles in Life Sciences
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 …
Stress Responses To Salinity In A Native Fresh Water Snake (Nerodia Rhombifer), Joana A. Cordoba
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, …
Great Curassow And Crested Guan Near Ciudad Victoria, Tamaulipas, Mexico, Timothy Brush
Great Curassow And Crested Guan Near Ciudad Victoria, Tamaulipas, Mexico, Timothy Brush
Biology Faculty Publications and Presentations
Great Curassow (Crax rubra) and Crested Guan (Penelope purpurascens) were rediscovered in the Ciudad Victoria area of southwestern Tamaulipas, Mexico for the first time since 1909. Birds were found in low elevation canyons containing permanent running water, with riparian forest dominated by Montezuma bald-cypress (Taxodium mucronatum) and steep scrub-covered slopes. These records represent the northernmost known points of the ranges of both species. Additional field work will be needed to determine whether these small populations are isolated from the nearest known populations in the El Cielo/Gómez Farías area of southern Tamaulipas.