Habitat fragmentation and drought represent a growing threat to many bird species, particularly within grassy biomes, which are especially sensitive to global change.

In this study, the authors show how the loss of grassland area and continuity caused by woody plant encroachment, together with fluctuations in seasonal rainfall patterns, can trigger a cascade of negative effects on the reproduction of the secretarybird. This large, terrestrial raptor of the grasslands and savannas of sub-Saharan Africa is strongly dependent on seasonal precipitation cycles.

Because the secretarybird is both an avian top predator and a species tightly linked to structurally open ecosystems, it may serve as a valuable bioindicator of ecosystem health and of the impacts of climate change on these environments.

The results reveal that the most productive areas were characterised by low to moderate levels of fragmentation, whereas highly fragmented landscapes showed the lowest productivity values, possibly due to greater influence of edge effects . Areas with minimal fragmentation exhibited the highest nesting success but lower nest density, resulting in intermediate average productivity. Rainfall mainly influenced nest abundance, which in turn had a positive effect on productivity, regardless of fragmentation level. These findings highlight not only the importance of maintaining extensive and continuous grassland patches, but also the ecological value of ecotonal environments for this species — provided that grasslands remain sufficiently large and connected.

The study further emphasises the urgency of understanding how climate change and habitat fragmentation interact to shape population and predator–prey dynamics. The authors also note the need for multi-year monitoring to fully capture the effects of climate change on this threatened raptor species.

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