The Hartlaub’s gull is a fairly small gull, with a length of approximately 36 cm. It is endemic to the west coast of South Africa and Namibia, and the islands that lie off that shore. It is seldom seen very far out to sea, preferring the coast and estuaries. It has largely white plumage; grey wings and back; dark red bill, legs and feet and dark brown eyes. It has a plain white head when not breeding, and takes on a lavender-grey coloured “hood” over its face and the upper nape of its neck during breeding. Sexes are similar in plumage and the males are slightly larger than the females.
The Hartlaub’s gull had adjusted well, perhaps too well, to the presence of humans and it is considered a nuisance within the Cape Town area. It becomes very tame and quite bold, but the main nuisance results from its raucous call and from the fouling of buildings. More serious is its presence at some airports where it can provide a risk to aircraft.
It is omnivorous and a common visitor to waste tips where it scavenges for any scraps of food. It also feeds on fish, mollusks and a wide range of small invertebrates which it often hunts while wading in shallow water. It is a very gregarious species and gathers in large numbers when feeding and when roosting overnight.
A very noisy bird, the Hartlaub’s gull has a raucous call that is not unlike that of a crow, “kwaarr”.
The Hartlaub’s gull is monogamous. A colonial breeder, it makes a nest of loosely woven sticks on rocky ground or, particularly in the Swakopmund-Walvis Bay area of Namibia, in a convenient reed bed. It will also commonly nest on man-made structures such as guano platforms and buildings. The female lays a clutch of between one and three blotched, light-brown or green eggs that hatch after an incubation period of approximately 25 days.
The scientific binomial for the Hartlaub’s gull is Larus hartlaubii; Larus from the Latin for a “gluttonous seabird”, hartlaubii after the German ornithologist and author Karl Hartlaub (1814 – 1900).