Hot Flushes

How Southern Ground-Hornbills keep their cool

- Andrew Mckechnie & Lucy Kemp

Few sounds are more evocative than the booming duets of Southern Ground-Hornbills, especially when they accompany the last few whoops of hyaenas, distant lions’ roars, deep hoots of a Verreaux’s Eagle-Owl and the sawing cough of a prowling leopard in the half-darkness just before dawn breaks over the African bush. The number of these stately birds of the savannas and woodlands of southern and East Africa has, however, declined sharply in recent decades because of habitat loss, poisoning and other human impacts. As a result, the species is now red-listed as Vulnerable globally and Endangered in South Africa, Swaziland and Namibia.

Another significant threat looming over the Southern Ground-Hornbill is climate change. In the 1970s Alan and Meg Kemp’s pioneering research on the ecology of this species in the Kruger National Park revealed that groundhornbills are, compared to many other species, relatively heat-intolerant and retreat to shade and begin panting at comparatively mild air temperatures. These observations, together with recent evidence that hot weather negatively impacts the physical condition and breeding success of many birds in subtle but nevertheless consequential ways, provided the stimulus for several recent and ongoing projects aimed at understanding how ground-hornbills are likely to fare under hotter future conditions.