Seabirds and shorebirds
African Black Oystercatcher, Haematopus moquini
Kathy Calf
Animal Demography Unit
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Photo Kathy Calf
African Black Oystercatcher adult
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Photo Kathy Calf
African Black Oystercatcher chicks
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Oystercatchers (Haematopus sp.) are shorebirds that inhabit most continental sea coasts.
There are thirteen species of Oystercatcher worldwide and nine of these species occur in the Southern
Hemisphere. The Northern Hemisphere species have been recorded to fly great distances between breeding
and non-breeding areas whereas the African Black Oystercatcher is largely resident, migrating only
short distances to nursary areas in Namibia after fledging and then returning to their natal sites to breed.
The African Black Oystercatcher is the largest of all the species. Adults have jet black plumage,
pinkish legs and a long, dagger-like orange-red bill. In addition its eye and eye ring are red.
There is sexual dimorphism, females being larger and heavier with longer bills; a male weighing
an average of about 660g and a female about 720g when fully grown.
African Black Oystercatchers can be found on both rocky and sandy shores throughout the year and
they attempt to breed in varied habitat types. They are territorial throughout the year, however,
during the non-breeding period they have been observed to form aggregations or roost in clubs.
This is thought 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. Unfortunately the Oystercatcher breeding season coincides with
summer and summer holiday periods when use of the coast is 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. In high-disturbance areas there are declining numbers of Oystercatchers as these
birds are unable to replace themselves. Chicks are speckled grey and brown with black bills but
on fledging, at about three-quarter adult weight, their feathers resemble those of the adults and
their bills have started turning orange. The immatures are easily distinguishable from the adults
for up to six months after fledging but thereafter it becomes more difficult.
