Hamerkop

The hamerkop (Scopus umbretta), also called the umbrette, is a medium-sized bird. It is the only living species in the genus Scopus and the family Scopidae. The species and family was long thought to sit with the Ciconiiformes but is now placed with the Pelecaniformes, and its closest relatives are thought to be the pelicans and the shoebill. The shape of its head with a long bill and crest at the back is reminiscent of a hammer, which has given this species its name after the Afrikaans word for hammerhead. It is a medium-sized waterbird with brown plumage. It is found in mainland Africa, Madagascar and Arabia, living in a wide variety of wetlands, including estuaries, lakesides, fish ponds, riverbanks, and rocky coasts. The hamerkop is a sedentary bird that often shows local movements.

The hamerkop takes a wide range of prey, mostly fish and amphibians, but shrimps, insects and rodents are taken too. Prey is usually hunted in shallow water, either by sight or touch, but the species is adaptable and will take any prey it can. The species is renowned for its enormous nests, several of which are built during the breeding season. Unusually for a wading bird, the nest has an internal nesting chamber where the eggs are laid. Both parents incubate the eggs and raise the chicks.

The species is not globally threatened and is locally abundant in mainland Africa and Madagascar. The International Union for Conservation of Nature (IUCN) has assessed it as being of least concern.

The hamerkop was first described by the French zoologist Mathurin Jacques Brisson in 1760 in his landmark Ornithologia, which was published two years after the tenth edition of Carl Linnaeus' Systema Naturae. The species was subsequently described and illustrated by French polymath Comte de Buffon. When the German naturalist Johann Friedrich Gmelin revised and expanded Linnaeus's Systema Naturae in 1788 he included the hamerkop and cited the earlier authors. He placed the species in the genus Scopus that had been introduced by Brisson and coined the binomial name Scopus umbretta.

Brisson's names for bird genera were widely adopted by the ornithological community despite the fact that he did not use Linnaeus' binomial system. The International Commission on Zoological Nomenclature ruled in 1911 that Brisson's genera were available under the International Code of Zoological Nomenclature, so Brisson is considered to be the genus authority for the hamerkop. The generic name, Scopus, is derived from the Ancient Greek skia for "shadow". The specific name umbretta is modified from the Latin for "umber" or "dark brown".

The hamerkop is sufficiently distinct to be placed in its own family, although the relationships of this species to other families has been a longstanding mystery. The hamerkop was usually included in the Ciconiiformes, but is now thought to be closer to the Pelecaniformes. Recent studies have found that its closest relatives are the pelicans and shoebill. Although the hamerkop is the only living member of its family, one extinct species is known from the fossil record. Scopus xenopus was described by ornithologist Storrs Olson in 1984 based on two bones found in Pliocene deposits from South Africa. Scopus xenopus was slightly larger than the hamerkop and Olson speculated based on the shape of the tarsus that the species may have been more aquatic.

The hamerkop is also known as the hammerkop, hammerkopf, hammerhead, hammerhead stork, umbrette, umber bird, tufted umber, or anvilhead.

Two subspecies are recognized—the widespread nominate race S. u. umbretta and the smaller of West African S. u. minor, described by George Latimer Bates in 1931. Two other subspecies have been proposed. S. u. bannermani of south-west Kenya is usually lumped with the nominate race. Birds in Madagascar have been suggested to be distinct, in which case they would be placed in the subspecies S. u. tenuirostris. That proposed subspecies was described by Austin L. Rand in 1936. It has also been suggested that birds near the Kavango River in Namibia may be distinct, but no formal description has been made.