The influence of climate variability on demographic rates of avian Afro-palearctic migrants

Abstract

Climate is an important driver of changes in animal population size, but its effect on the underlying demographic rates remains insufficiently understood. This is particularly true for avian long-distance migrants which are exposed to different climatic factors at different phases of their annual cycle. To fill this knowledge gap, we used data collected by a national-wide bird ringing scheme for eight migratory species wintering in sub-Saharan Africa and investigated the impact of climate variability on their breeding productivity and adult survival. While temperature at the breeding grounds could relate to the breeding productivity either positively (higher food availability in warmer springs) or negatively (food scarcity in warmer springs due to trophic mismatch), water availability at the non-breeding should limit the adult survival and the breeding productivity. Consistent with the prediction of the trophic mismatch hypothesis, we found that warmer springs at the breeding grounds were linked with lower breeding productivity, explaining 29% of temporal variance across all species. Higher water availability at the sub-Saharan non-breeding grounds was related to higher adult survival (18% temporal variance explained) but did not carry-over to breeding productivity. Our results show that climate variability at both breeding and non-breeding grounds shapes different demographic rates of long-distance migrants.

Species Traits Drive Long-Term Population Trends of Common Breeding Birds in Northern Italy

“…Our analyses detected a general decline of migrant species, and a positive but non-significant trend for sedentary species. The decline of long-distance migrants has been extensively outlined for European breeding birds [ 42 , 138 , 139 ], with some exceptions (e.g., in Estonia [ 140 ]), and several explanations have been proposed (e.g., drought of Sahel areas, habitat loss and degradation, hunting, phenological mismatch [ 42 , 138 , 141 , 142 , 143 , 144 , 145 , 146 ]). Moreover, long-distance migrants were proved to decline faster than short-distance migrants in Europe [ 22 , 35 , 42 ], but we did not detect such a difference between the two groups, corroborating the idea that geographic variation in trends may occur [ 139 ].…”

Wildlife‐vehicle collisions in Moroccan Atlantic Sahara: Impact on resident species and Afro‐Palearctic birds for conservation purposes

“…These measures are not very expensive and they were tested and approved elsewhere with confident results (Benten et al, 2018; Brieger et al, 2017). Moreover, the installation of illustrative panels along coastal migratory routes will protect millions of Afro‐Palearctic birds, including the vulnerable species that use coasts for forage and staging (Parolini et al, 2021; Telenskỳ et al, 2020).…”

Recognition of Endemic Bird Species Using Deep Learning Models

“…Along with other native organisms, birds play a crucial role in balancing an ecosystem. They are considered keystone species that help maintain sustainable population levels between all living things in the overall web of life [3]. Even a slight decrease in their number endangers the entire ecosystem [4].…”