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Mexico has eight endemic lagomorph species, several of which are endangered. For conservation reasons it is necessary to know more about their diet. In a first step we applied the method of fecal pellet analysis to the cottontailSylvilagus floridanus (Allen, 1890). Since it is common in Mexico, information on its diet should provide a useful baseline with which to compare the diets of other Mexican lagomorphs. At Ixtacuixtla, we recorded vegetation and analyzed fecal pellet content once in August (wet season) and once in March (dry season) at 4 sampling sites representing different habitat types. The comparison of vegetation and diet records suggestedS. floridanus to occupy the same dietary niche in the different habitats. Measures of niche breadth showedS. floridanus to be neither a generalist nor a specialist. Nevertheless, it appeared to be quite selective in consuming particular herb and grass species even when they became scarce during the dry season. Since the vegetation record only poorly represented the rabbits’ diet, a more focused approach is suggested for future studies: first, to identify the relevant food species in the diet, second, to obtain data on the availability of these, and third, to concentrate on time points when changes in resource state could be a limiting factor.
This study evaluates and compares habitat preferences and spatial niche breadth and overlap between two sympatrically occurring species, the sand cat (Felis margarita) and Rüppell's fox (Vulpes rueppellii), in a desert landscape of central Iran. A field survey from 2014 to 2016 was conducted to collect occurrence points for the two species as well as to identify their structural characteristics of used habitats in the occurrences points. Jacobs' index as a measure of habitat preference, Shannon and Levins' indices as measures of niche breadth, MacArthur, Levins and Pianka's indices as measures of niche overlap were calculated and interpreted. The results of this study showed that the sand cats are specifically restricted to sand dune and sabulous habitat type, whereas Rüppell's foxes have wider ecological amplitude. Sand cats only prefers sand dunes while Rüppell's foxes were found to prefer foothills, badlands, and sand dunes. Rüppell's foxes therefore had a wider niche breadth compared to the sand cats. The asymmetric MacArthur and Levins indices yielded a higher value of niche overlap for the sand cats compared to Rüppell's foxes, while the symmetric Pianka's measure of niche overlap was relatively high for both species. Such habitat preference and niche segregation between the two species may be a result of their feeding habits or the physical protective structure of their habitats attributes.
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