High temperatures and human pressures interact to influence mortality in an African carnivore

The impacts of high ambient temperatures on mortality in humans and
domestic animals are well understood. However, much less is known about
how hot weather affects mortality in wild animals. High ambient
temperatures have been associated with African wild dog Lycaon pictus pup
mortality, suggesting that high temperatures might also be linked to high
adult mortality. We analysed mortality patterns in African wild dogs
radio-collared in Kenya (0°N), Botswana (20°S), and Zimbabwe (20°S), to
examine whether ambient temperature was associated with adult mortality.
We found that high ambient temperatures were associated with increased
adult wild dog mortality at the Kenya site, and there was some evidence
for temperature associations with mortality at the Botswana and Zimbabwe
sites. At the Kenya study site, which had the highest human
impact, high ambient temperatures were associated with increased risks of
wild dogs being killed by people, and by domestic dog diseases. In
contrast, temperature was not associated with the risk of snare-related
mortality at the Zimbabwe site, which had the second-highest human impact.
Causes of death varied markedly between sites. Pack size was
positively associated with survival at all three sites. These
findings suggest that while climate change may not lead to new causes of
mortality, rising temperatures may exacerbate existing anthropogenic
threats to this endangered species, with implications for conservation.
This evidence suggests that temperature-related mortality, including
interactions between temperature and other anthropogenic threats, should
be investigated in a greater number of species to understand and mitigate
the likely impacts of climate change.