Dataset Information

An advanced method to assess the diet of free-ranging large carnivores based on scats.

ABSTRACT:

Background

The diet of free-ranging carnivores is an important part of their ecology. It is often determined from prey remains in scats. In many cases, scat analyses are the most efficient method but they require correction for potential biases. When the diet is expressed as proportions of consumed mass of each prey species, the consumed prey mass to excrete one scat needs to be determined and corrected for prey body mass because the proportion of digestible to indigestible matter increases with prey body mass. Prey body mass can be corrected for by conducting feeding experiments using prey of various body masses and fitting a regression between consumed prey mass to excrete one scat and prey body mass (correction factor 1). When the diet is expressed as proportions of consumed individuals of each prey species and includes prey animals not completely consumed, the actual mass of each prey consumed by the carnivore needs to be controlled for (correction factor 2). No previous study controlled for this second bias.

Methodology/principal findings

Here we use an extended series of feeding experiments on a large carnivore, the cheetah (Acinonyx jubatus), to establish both correction factors. In contrast to previous studies which fitted a linear regression for correction factor 1, we fitted a biologically more meaningful exponential regression model where the consumed prey mass to excrete one scat reaches an asymptote at large prey sizes. Using our protocol, we also derive correction factor 1 and 2 for other carnivore species and apply them to published studies. We show that the new method increases the number and proportion of consumed individuals in the diet for large prey animals compared to the conventional method.

Conclusion/significance

Our results have important implications for the interpretation of scat-based studies in feeding ecology and the resolution of human-wildlife conflicts for the conservation of large carnivores.

SUBMITTER: Wachter B

PROVIDER: S-EPMC3371055 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Publications

An advanced method to assess the diet of free-ranging large carnivores based on scats.

Wachter Bettina B Blanc Anne-Sophie AS Melzheimer Jörg J Höner Oliver P OP Jago Mark M Hofer Heribert H

PloS one 20120608 6

<h4>Background</h4>The diet of free-ranging carnivores is an important part of their ecology. It is often determined from prey remains in scats. In many cases, scat analyses are the most efficient method but they require correction for potential biases. When the diet is expressed as proportions of consumed mass of each prey species, the consumed prey mass to excrete one scat needs to be determined and corrected for prey body mass because the proportion of digestible to indigestible matter increa ...[more]

PMID: 22715373

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Dataset Information

An advanced method to assess the diet of free-ranging large carnivores based on scats.

Background

Methodology/principal findings

Conclusion/significance

Publications

An advanced method to assess the diet of free-ranging large carnivores based on scats.

Similar Datasets

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