The Herpetological Journal

Authors: Pawan Shantiprakash Pareek, Monowar Alam Khalid, Christopher J. Michaels & Shailendra Singh

Abstract: The Critically Endangered red-crowned roofed turtle Batagur kachuga is a large riverine turtle found in the Gangetic Plain of Northern India; a habitat specialist, it nests exclusively on sandbanks. We examined female nest site selection based on a suite of physical environmental factors. Data were collected from sandbanks within the species range. Known nest sites were sampled for variables defining nest site size, position, moisture content, slope angle, adjacent water depth, pH and substrate particle size composition, and similar data were collected from analogous positions on unused banks. In addition to summarising variables for nest sites to characterise their physical characteristics, we employed a Principal Component Analysis (PCA) to handle multi-collinear data, followed by logistic regression to examine the influence of variables on nest site preferences. Among five detected PCA dimensions, one, primarily influenced by substrate moisture, particle size, slope angle and adjacent water depth, was a significant predictor of nest site selection. This study enhances the understanding of nesting habitat preferences for this turtle, offering insights for its management and conservation efforts.

Keywords: Chambal river, freshwater, protected area, nest site selection, nesting ecology, PCA, Bayesian logistic regression