The secretary bird (Sagittarius serpentarius) is a distinctive, long-legged raptor of African grasslands, spending most of its time walking through open savanna hunting snakes and other prey on foot. Its populations have declined by 60% in 20 years as African grasslands are degraded and converted.
Secretary birds in degraded grasslands cannot maintain the foraging success needed to raise chicks. Reduced prey availability requires longer daily walks, increasing energy expenditure without proportional reward. Nest disturbance during the dry season when trees are leafless — making nests more visible — causes abandonment of eggs or small chicks. Agricultural expansion that converts open grassland to crops or closed bush eliminates hunting habitat completely, forcing birds to vacate territories. The welfare of a ground-hunting bird is intimately linked to the quality and extent of open grassland within its range — a habitat disappearing rapidly across sub-Saharan Africa.