Trait-based sensitivity of large mammals to a catastrophic tropical cyclone: DNA metabarcoding data

Extreme weather events perturb ecosystems and increasingly threaten
biodiversity1. Ecologists emphasize the need to forecast and mitigate the
impacts of these incidents, which requires knowledge of how risk is
distributed among species and environments, but the scale and
unpredictability of extreme events complicates assessment1–4. These
challenges are compounded for large animals (‘megafauna’), which play
crucial ecological roles but are hard to study5. Traits such as body size,
dispersal ability, and habitat affiliation are among the hypothesized
determinants of animals’ vulnerability to natural hazards1,6,7. However,
it has rarely been possible to test these propositions or, more generally,
to link short- and longer-term effects of weather-related disturbance8,9.
Here, we show how large herbivores and carnivores in Mozambique responded
to Intense Tropical Cyclone Idai, the deadliest storm on record in Africa,
across scales ranging from individual decisions in the hours after
landfall to community-level responses nearly 20 months later. Animals
occupying low-elevation habitats exhibited strong spatial responses to
rising floodwaters. Body size predicted species’ subsequent numerical
responses: small-bodied species exhibited the greatest population
declines. We trace this sensitivity to limited mobility, which increased
likelihood of death during the flood and constrained animals’ capacity to
withstand food shortages afterward. Our results identify potentially
general trait-based mechanisms underlying animal responses to severe
weather and may help to inform strategies for wildlife conservation in a
volatile climate. Climate Change 2022: Impacts, Adaptation and
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