The landscapes of thirst: behavioural adjustments to face water scarcity in a changing climate – LANDTHIRST

Climate change threatens the availability of surface water in many places. Water is essential to life, and most animal species need to drink, always, during some specific periods of the year, or during extreme climatic events (e.g. heat waves). The inability for individuals to drink, even for a short period of time, may sometimes threaten entire populations. When faced with a lack of water, individuals need to shift their diet towards water-rich food items or search for water in the landscape. Are these changes in diet costly, leading to poorer diet quality? How do animals know where to find other water sources before dehydration hits? Why do animals use areas where they could be trapped without water, rather than remain near permanent water sources? These are critical questions in the context of understanding the impact of climate change, but they remain unanswered. Their study is the goal of the LANDTHIRST project, which has the ambition to be the first integrative study of behavioural adjustments of wildlife to the lack of water.

LANDTHIRST will be conducted using two African ungulates as model species (Plains zebra (Equus quagga) and Greater kudu (Tragelaphus strepsiceros)) in one of the largest African protected areas (Hwange National Park, Zimbabwe)), which is also a French Long-Term Ecological Research site and a rare long-term observatory of climate change and its ecosystems impacts. The challenge of studying animal behaviour in the wild will be addressed by using a combination of methodological approaches: for example, we will study the spatial behaviour of individuals with GPS-tracking, movement modelling and newly developed analyses of recursion patterns; diet composition and quality will be studied using DNA-barcoding and near-infra-red spectroscopy; isotopic analyses will reveal the changes in the source of water consumed.

Overall LANDTHIRST will (i) produce immediate knowledge on the impact of climate change on species, with a case study based on African savannas, ecosystems of cultural and environmental interest at the global scale; (ii) pave the way for a greater awareness of the impact of changes in drinking water availability for wildlife and biodiversity, while offering conceptual and methodological advances in the scientific study of these effects in other systems.