African Black Oystercatcher

Haematopus moquini - The African Black Oystercatcher

The African Black Oystercatcher also known as African oystercatcher, is a large wader which is a resident breeder on the rocky coasts and islands of southern Africa.

The African Black Oystercatcher is the largest of the Oystercatcher species. It is a large and noisy plover-like bird, unmistakable with its beautiful jet black plumage, pinkish/red legs and strong broad dagger-like red bill which it uses for smashing or prying open molluscs such as mussels, or for finding earthworms.

Did you know? The De Hoop Nature Reserve in the Western Cape is an ideal place to spot the African Black Oystercatcher in good numbers.

The eyes and eye rings are red. The Black Oystercatcher is unmistakable in flight with its rather impressive all-dark plumage. Although the sexes are very similar in appearance, the females are larger and heavier with longer bills. Juveniles are browner than adults.

Size

Length is 42 - 45 cm.

The male weighs an average of 660g and the female weights 720g when fully grown.

Habitat

The African black oystercatcher lives on rocky and sandy shores but it can also be found in estuaries and coastal lagoons. However, it prefers to breed on offshore islands and sandy beaches.

Distribution

African black oystercatcher is commonly found along the southern African coast all the way from from northern Namibia to the Eastern Cape in South Africa. In South Africa, large flocks of them can be found all along the coast from Lamberts Bay and Arniston in the Western Cape through to Mazeppa Bay on the Wild Coast in the Eastern Cape.

Diet

Black Oystercatcher eat limpets and mussels (not oysters). They can only feed at low tide and do so at day and night. Because of their highly selective feeding area they are more susceptible to human activity than most other shore birds.

Abandoned or entangled fishing line is particularly dangerous for these birds as they easily become entangled in it with lethal results.

Socialisation

Highly territorial throughout the year, during the non-breeding period African Black Oystercatchers have been observed to form aggregations or roost in clubs. This is believed to function in predator avoidance as clubs are usually situated on offshore rocks or promonitories with good all-round visibility. These clubs tend to contain more birds at night when predation risk is greater.

Communication

The African Black Oystercatcher mates for life.

Reproduction

The nest is a bare scrape on pebbles or shingles. The female generally lays 2-4 eggs, which are incubated by both adults. The Oystercatchers breeding season coincides with summer and summer holiday periods when use of the coast is usually at its peak.

As a result, in many areas birds are unable to breed successfully, due to disturbance and increased predation risk as a result of disturbance. Although they may live for 35 years they do not breed until they are three years old.

Incubation

The eggs are incubated by both parents and hatch after 27 to 39 days.
Young fledge at between 35 to 40 days of age.

Life Expectancy

Reports on life expectancy vary from 18 to 40 years.

Predators

During the breeding period these birds, their eggs and chicks are vulnerable to natural predators such as foxes, jackals, genets, snakes and gulls.

Their breeding time is during the summer which coincides with the holiday season - this puts the oystercatcher under additional threat as its space is invaded by humans (and their dogs) who make their way to the coast for the holidays and weekends.