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The conflict between cheetahs and humans on Namibian farmland elucidated by stable isotope diet analysis.

ABSTRACT: Large areas of Namibia are covered by farmland, which is also used by game and predator species. Because it can cause conflicts with farmers when predators, such as cheetahs (Acinonyx jubatus), hunt livestock, we assessed whether livestock constitutes a significant part of the cheetah diet by analysing the stable isotope composition of blood and tissue samples of cheetahs and their potential prey species. According to isotopic similarities, we defined three isotopic categories of potential prey: members of a C4 food web with high ?15N values (gemsbok, cattle, springhare and guinea fowl) and those with low ?15N values (hartebeest, warthog), and members of a C3 food web, namely browsers (eland, kudu, springbok, steenbok and scrub hare). We quantified the trophic discrimination of heavy isotopes in cheetah muscle in 9 captive individuals and measured an enrichment for 15N (3.2‰) but not for 13C in relation to food. We captured 53 free-ranging cheetahs of which 23 were members of groups. Cheetahs of the same group were isotopically distinct from members of other groups, indicating that group members shared their prey. Solitary males (n?=?21) and males in a bachelor groups (n?=?11) fed mostly on hartebeest and warthogs, followed by browsers in case of solitary males, and by grazers with high ?15N values in case of bachelor groups. Female cheetahs (n?=?9) predominantly fed on browsers and used also hartebeest and warthogs. Mixing models suggested that the isotopic prey category that included cattle was only important, if at all, for males living in bachelor groups. Stable isotope analysis of fur, muscle, red blood cells and blood plasma in 9 free-ranging cheetahs identified most individuals as isotopic specialists, focussing on isotopically distinct prey categories as their food.

SUBMITTER: Voigt CC

PROVIDER: S-EPMC4146470 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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The conflict between cheetahs and humans on Namibian farmland elucidated by stable isotope diet analysis.

Voigt Christian C CC Thalwitzer Susanne S Melzheimer Jörg J Blanc Anne-Sophie AS Jago Mark M Wachter Bettina B

PloS one 20140827 8

Large areas of Namibia are covered by farmland, which is also used by game and predator species. Because it can cause conflicts with farmers when predators, such as cheetahs (Acinonyx jubatus), hunt livestock, we assessed whether livestock constitutes a significant part of the cheetah diet by analysing the stable isotope composition of blood and tissue samples of cheetahs and their potential prey species. According to isotopic similarities, we defined three isotopic categories of potential prey: ...[more]

PMID: 25162403

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The conflict between cheetahs and humans on Namibian farmland elucidated by stable isotope diet analysis.

Publications

The conflict between cheetahs and humans on Namibian farmland elucidated by stable isotope diet analysis.

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