Data from: Global trends in drought impacts on wildlife: A review

We conducted a systematic review of peer-reviewed articles from 1982-2024,
focusing on the impacts of anomalous drought on terrestrial vertebrates.
We recorded 3,324 total wildlife responses, 188 from single-species
studies and 3,136 from multi-species studies. Within single-species
studies, 66% of responses were negative, 32% were unclear, and 2% were
positive, illustrating the widespread threat of increasing drought to
global wildlife. Within multi-species studies, 24% of responses were
negative, and 5% were positive. Notably, 71% of responses within
multi-species papers were categorized as ‘unclear’, highlighting the need
for additional investigation and the complexity of synthesizing a diverse
literature. Drought impacts are not evenly tested across taxa, with birds
being the most frequently studied (51% of documented responses), followed
by mammals (28%), amphibians (16%), and reptiles (5%). Geographically,
studies tended to occur most often where recent increases in anomalous
drought have been observed (e.g., the Southwestern United States, South
Africa, and Southeastern Australia). The sophistication of how drought is
measured has increased over time, whereby studies increasingly defined
drought as an anomalous event in comparison to a long-term average through
the use of drought indices, rather than as a short-term weather event.
However, we did not see consistency in indices used across the literature,
which has the potential to present challenges for interpretation and
synthesis. This review summarizes the predominantly negative impacts of
drought on terrestrial vertebrates and the growing challenge of conserving
wildlife in a changing world, while also highlighting gaps in our
understanding of drought-wildlife relationships that can guide future
research.