Black Oystercatcher
[order] CHARADRIIFORMES | [family] Haematopodidae | [latin] Haematopus bachmani | [UK] Black Oystercatcher | [FR] Huitrier de Bachmann | [DE] Klippen-Austernfischer | [ES] Ostrero Negro | [NL] Noordamer.Zwarte Scholekster
Subspecies
Monotypic species
Physical charateristics
A large, heavily built, blackish shorebird, with a straight red bill, flattened laterally. Legs a pale flesh color. Immature may have a black tip on the bill.
Listen to the sound of Black Oystercatcher
[audio:http://www.aviflevoland.nl/sounddb/B/Black Oystercatcher.mp3]
Copyright remark: Most sounds derived from xeno-canto
| wingspan min.: | 77 | cm | wingspan max.: | 86 | cm |
| size min.: | 42 | cm | size max.: | 47 | cm |
| incubation min.: | 26 | days | incubation max.: | 28 | days |
| fledging min.: | 1 | days | fledging max.: | 1 | days |
| broods: | 1 | eggs min.: | 1 | ||
| eggs max.: | 3 |
Range
North America : West coast
Habitat
Rocky coasts, sea islets.
Found at all seasons along rocky shorelines, especially on small offshore islands where predators are fewer; chooses areas with abundant shellfish and other marine life. In winter, also commonly found on mudflats close to rocky coastlines, but uses mudfla
ts less in summer.
Found at all seasons along rocky shorelines, especially on small offshore islands where predators are fewer; chooses areas with abundant shellfish and other marine life. In winter, also commonly found on mudflats close to rocky coastlines, but uses mudfla
ts less in summer.
Reproduction
May mate for life. Almost always nests on islands. Pairs typically defend breeding territory that includes both an elevated area for nesting and an adjacent feeding area in intertidal zone.
Nest: Site is on ground well above high tide mark, on gravel, grassy area, or depression in rock. Nest (built by both sexes) is slight scrape, with sparse lining of pebbles, pieces of shell.
Eggs: 2-3, sometimes 1. Pale buff to olive, spotted and scrawled with brown and black. Incubation is by both parents, 24-29 days.
Young: Downy young remain near nest at first; parents take turns guarding the young and going to get food for them. Older chicks follow their parents to feeding areas and ar
e fed by them there. Young can fly at age 5 weeks or older; are fed by parents for some time thereafter.
Nest: Site is on ground well above high tide mark, on gravel, grassy area, or depression in rock. Nest (built by both sexes) is slight scrape, with sparse lining of pebbles, pieces of shell.
Eggs: 2-3, sometimes 1. Pale buff to olive, spotted and scrawled with brown and black. Incubation is by both parents, 24-29 days.
Young: Downy young remain near nest at first; parents take turns guarding the young and going to get food for them. Older chicks follow their parents to feeding areas and ar
e fed by them there. Young can fly at age 5 weeks or older; are fed by parents for some time thereafter.
Feeding habits
Mostly mussels, limpets, marine worms.
Feeds mostly on mussels where they are abundant; also limpets, marine worms, crabs, beetle larvae. Young birds, newly independent, may eat fewer mussels at first, perhaps lacking the skill to open them.
Behavior:
Finding a mussel with its shell slightly open, the oystercatcher jabs its bill into the opening, cutting the muscles and then cleaning out contents. Probes in mud, and pries limpets off of rocks. When feeding on mussel beds, typically removes the mussel
from its shell and leaves the shell in place.
Feeds mostly on mussels where they are abundant; also limpets, marine worms, crabs, beetle larvae. Young birds, newly independent, may eat fewer mussels at first, perhaps lacking the skill to open them.
Behavior:
Finding a mussel with its shell slightly open, the oystercatcher jabs its bill into the opening, cutting the muscles and then cleaning out contents. Probes in mud, and pries limpets off of rocks. When feeding on mussel beds, typically removes the mussel
from its shell and leaves the shell in place.
Conservation
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be small, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Migration
Resident from western Aleutians (Attu), east and south along coast to Morro Bay, California; on offshore islands to Baja California. Migration:
Mostly permanent resident. No regular migration, but wanderers away from breeding areas are most likely to be seen in spring and fall.
Mostly permanent resident. No regular migration, but wanderers away from breeding areas are most likely to be seen in spring and fall.
Distribution map
