Simulated genetic efficacy of metapopulation management and the conservation value of captive reintroductions in a rapidly declining felid

In South
Africa, cheetah (Acinonyx jubatus)
occur as a relictual, unmanaged population of ‘free-roamers’, a managed
metapopulation across fenced reserves, and in various captive facilities. To
ensure that the Cheetah Metapopulation Project (CMP) is not at risk of losing
overall genetic variation to drift or inbreeding, we propose various
interventions, including exchanges between free-roamers and the metapopulation
or supplementation with unrelated individuals from captivity. Simulated
trajectories of genetic diversity under such intervention strategies over time
could directly inform conservation action and policy towards securing the long-term
genetic integrity of the CMP. Single Nucleotide Polymorphisms (SNPs) were
genotyped for 172 adult cheetah across the free-roamer population, the
metapopulation, and three major captive facilities. Management intervention trajectory
models were tested including, 1) no intervention, 2) genetic exchange between
free-roamers and the metapopulation, 3) translocation from a single captive
facility and 4) translocation from several captive facilities into the
metapopulation. Discriminant Analysis of Principal Components (DAPC) showed
that the two captive populations are highly differentiated from the
metapopulation and each other, while the third captive and free-roamer
populations are genetically more similar to the metapopulation. Simulated
genetic variation over 25 generations indicated that models 1 and 2 show
significant losses of heterozygosity due to genetic drift and present a
proportional increase in the frequencies of first- and second-degree relatives,
while this variation and pairwise relatedness remain relatively constant under
models 3 and 4. We emphasise the potential importance of captive facilities as
reservoirs of genetic diversity in metapopulation management and threatened
species recovery.