Effects of habitat loss on populations of the Argentine Boa Constrictor (Boa constrictor occidentalis)

GABRIELA CARDOZO1, PAULA C. RIVERA1,2 , MARIO LAMFRI3, MARCELO SCAVUZZO3, CRISTINA GARDENAL2 AND MARGARITA CHIARAVIGLIO1

Biology of Boas and Pythons

Eagle Mountain Publishing. USA

Año: 2006; p. 300 - 311

Abstract: The study of spatial patterns and ecological processes as a whole provides new ways to understand why landscape transformations make some species prone to population decline and range contraction. Fragmentation, caused by human-induced disturbances, affects ecosystems by modifying the distribution of resources among patches and altering intraspecific processes, like gene flow and genetic drift. The Argentine boa constrictor (Boa constrictor occidentalis) is the southernmost big subspecies of boids in the American continent, being its largest distribution in Argentina. Its natural habitat is being rapidly and severely deteriorated due to the intensive cattle raising, farming and extraction of woody species. The aim of this work was to analyze the way in which heterogeneous spatial patterns influence population genetic parameters. Our study area included 9 sampling sites in the Northwestern Córdoba Province -Argentina- and covered approximately an extent of 200 000 ha. We analyzed satellital images Landsat 7 +ETM employing ENVI 3.5 program (System Research). We analyzed the genetic structure using allozymes and ISSR as molecular markers. Our results suggest that the ecological processes that model the population genetic structure of Boa constrictor occidentalis could be responding to the changes in spatial patterns of the landscape.