The impact of rising temperatures on the water usage of the Eleonora's falcon (Falco eleonorae) during its pre-breeding period

Abstract

The significant increase in global warming has multiple impacts on biodiversity. These impacts do not affect all ecosystems in the same way. Some regions, such as the Mediterranean, are already being severely affected by aridification. This study examines the impact of this rise in temperature on the Eleonora's falcon (Falco eleonorae). This emblematic bird of prey, which breeds on Mediterranean cliffs, has a particular ecology that makes it potentially vulnerable to the threat of drought. Specifically, this study focused on the falcon's use of water during the less studied pre-breeding period on a small island in Greece. The duration of water bathing and wetting and the frequency of drinking, which are thermoregulatory behaviours in birds, were correlated with temperature. These correlations confirm a relationship between rising temperatures and water use behaviour, especially for the drinking frequency. These behaviours, which are more pronounced on days when the temperature is higher, show that the falcon needs this water to regulate its body temperature. A comparison of these behaviours as a function of the variation in plumage (dark morph and light morph) of the falcons was also carried out but showed no variation. This study, among others, provides valuable information for future conservation projects for the species.