Oystercatcher

Haematopus ostralegus

Strikingly plumaged wader with large bill for bashing shellfish.

Oystercatcher

Length:

40cm to 45cm

Wingspan:

80cm to 86cm

Weight:

430g to 650g

What does a Oystercatcher look like?

The oystercatcher is a boldly plumaged wader, easily distinguished by its heavy orange bill and red eyes, with orange orbital ring. It is a large bird, compact and deep-chested. Its appearance is of white below and black head and upperparts. Its wings have a black leading edge and a broad white wing bar that is conspicuous during flight. Males have on average a shorter and thicker bill than females. Males also sometimes have a brighter red base of bill, but distinguishing sexes is generally quite difficult. Females are also usually heavier. The oystercatcher has relatively long and sturdy legs, which are pink. Newly fledged juveniles are exceptionally well camouflaged to resemble lichen-covered rocks. In winter, the birds acquire a white collar. First winter birds are paler than adults with a larger, white throat patch or ‘chinstrap’.

Close up of an Oystercatcher

Close up of an Oystercatcher

What does a Oystercatcher sound like?

Ostercatchers are noisy birds. Their loud, shrill ‘peep-ing’ call is a recognisable and familiar sound of the seashore. They also have a loud ‘kubeek kubeek’ alarm call.

Oystercatcher call

Will Scott, XC632760. Accessible at www.xeno-canto.org/632760.

Oystercatcher in flight

Oystercatcher in flight

What does a Oystercatcher eat?

Despite their name, oystercatchers, do not eat oysters, they prefer mussels and cockles. They will probe through the mud with their bills for marine worms, and inland birds will eat earthworms. Oystercatcher bills vary in shape depending on what they eat, parents pass on these traits onto their young. Birds with longer bills specialise in prising cockles apart, while those with blunt bills hammer the tougher mussel shells.

Oystercatcher searching for food

Oystercatcher searching for food

Where can I see Oystercatchers?

The oystercatcher is primarily a shorebird but breeds inland by rivers, lochs, flooded gravel pits, stony lake shores and estuaries. In winter, the bird is more strictly coastal, and during this time they tend to roost communally. Oystercatchers are common on shorelines where there are molluscs such as cockles and mussels to feed on. In Britain, they can be seen all year round.

Did you know?

Oystercatchers have just three forward-facing toes, which helps to spread their weight to stop them sinking in the mud.

Signs and Spotting tips

Oystercatchers roost communally, so are usually found in areas that provide safe height-tide roosts as well as good feeding areas. Oystercatchers make a remarkable spectacle flying through the air in flocks in formations with their white wing bars flashing. Their flight is direct with quick wingbeats, somewhat recalling a duck. RSPB reserves on estuaries are a good place to see oystercatchers. Look out for them along mudflats, or along the warm shingle in summer.

How does a Oystercatcher breed?

Oystercatchers breed on open, flat coasts. In the breeding season, flocks disperse and spread themselves out around the coast and along broad, stony rivers, usually nesting among the rocks, sometimes on a promontory. Their nest is a shallow scrape in the open, lined with pebbles and shells. Oystercatchers are territorial and usually monogamous.

The female will lay 3 eggs are which are slightly glossy, buff-yellow with many dark spots, blotches and streaks. Eggs are laid between April and May. They will be incubated for 24-35 days. Incubation is shared, but females do most of the work, while males defend the territory. The pair will raise 1 brood a year. Birds reach sexual maturity after 3-5 years. The species sometimes lay their eggs in the nests of other birds and leave them to be raised by the host.

Oystercatcher nest with eggs

Oystercatcher nest with eggs

How long do Oystercatchers live for?

Oystercatchers typically live for 12 years. However, the record stands at 40 years, one month and two days.

Do Oystercatchers migrate?

In Britain, oystercatchers are resident and widespread, with a winter influx of birds from all over Europe.

Threats and conservation

Oystercatchers are in competition with fisherman and numbers were traditionally culled in order to tip the balance toward people. However, numbers have made a comeback in recent times, although the species’ still has a UK conservation status of Amber. The UK breeding population amounts to around 110,000 pairs. The UK wintering population is approximately 340,00 birds.