EPOW - Ecology Picture of the Week

Explanation:   Bet you were thinking of a woodpecker when you read "the bird with the hammer head."  Instead, this is a Hamerkop, a bird related to storks and herons and that is widely distributed in sub-Sahara Africa.  

Also called "Hammerheads," Hamerkops are about half a meter tall (about a foot and a half), a large waterbird of lakes, rivers, and marshes.  They are the only member of the family Scopidae which seems to have no close relatives.  Their "hammer" head is of course formed by a uniquely backward-pointing plumage crest. 

Hamerkops feed largely on adults and tadpoles of the frog genus Xenopus, as well as on small fish, aquatic invertebrates, and insects.  Like some herons, it uses its feet to stir up prey while walking in shallow water.  

Hamerkops build huge domed nests in large riparian trees such as the one shown here at right.  I found this nest along a stream in Njobvu, northern Malawi, Africa, and it was also occupied by a Giant Eagle-owl who used it as a daytime roost and perch site.  

Hamerkop on snag.
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