- Appearance: black head, brown back, white stripe on wings and tail, long red/orange beak, yellow eyes surrounded by yellow ring, pale pink legs, white undersides
- Females are larger than males, identical plumage
- Height: 17-21 inches (about 1.5 feet)
- Wingspan: 35 inches (about 3 feet)
- Status: recovered from severe decline in 1800s; common, but threatened by habitat displacement and overharvesting of shellfish
- Habitat
- Sand/shell beaches, dunes, salt marshes, marsh islands, mudflats
- Roost near foraging sites, rarely venture inland
- Threatened by habitat loss from human development and competition with gulls that also lose their habitat because of humans
- Common along East Coast of United States, Gulf Coast and Mexico
- Sometimes populations can be found in California, but usually the black oystercatcher is found on the West Coast
- Diet
- Specialize in eating bivalves (oysters, clams, mussels, scallops, etc.), also eats crabs, sea urchins, sea stars, marine worms, jellyfish
- Spend most of foraging time walking
- Wade through shallow water to look for food
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- When they spot an open bivalve, they jab their beak in between the shells and cut the muscle that closes them to prevent the bivalve from closing
- Common but risky strategy – they can drown if shellfish clamps on beak
- Carry loose shellfish out of water and hammer at shell and probe for buried clams
- Often lose food to seagulls, which is why they try to avoid them
- When they spot an open bivalve, they jab their beak in between the shells and cut the muscle that closes them to prevent the bivalve from closing
- Migration
- Birds from Long Island to Florida are nonmigratory
- Breeding birds migrate north to Connecticut to Nova Scotia, Canada
- Spring migration occurs February-April
- Wintering birds migrate south to Florida, Caribbean, and Central America
- Fall migration occurs August to mid-November
- The farther north a bird breeds, the farther south it travels for winter
- “Leapfrogging” = passing over territory of nonmigratory birds
- Form flocks during breeding and wintering seasons, but migrate alone
- Average flight speed is about 20mph, can reach up to 40mph while migrating
- First year birds usually over summer in winter range for 1-3 years before migrating to breeding grounds
- Nesting
- Sometimes mate for life, but many find different mates each year
- In areas with large amount of oystercatchers, males may mate with two females
- Nest on high, sandy sites
- Parents usually return to same site, unless it is frequented by humans or seagulls
- Attack other birds who approach nest, fly away from people as distraction tactic
- Both parents scrape about 5 depressions in sand, choose which site is best
- Nests are lined with pebbles and shells
- Sometimes lack of suitable nesting ground forces oystercatchers to nest on high tide line – nests may flood during high tides
- Average brood is 2-4 gray eggs with brown speckles
- Nests with one male and two females has about 5-6 eggs
- Hatchlings often leave the nest the day they hatch
- Juvenile oystercatchers have black eyes which change to yellow when they mature – their eye color from there darkens as they age
- Parents feed young for about 2 weeks after hatching, but they may learn to forage well before their parents stop feeding them
- Fledglings take their first flight at about 5 weeks old
- Parents care for offspring for about one month after first flight, until they part ways during the fall migration
- Average lifespan is about 15 years, but the oldest American oystercatcher was about 24 years old
