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Black Oystercatcher
Haematopus bachmani
Black Oystercatcher
Science
Black Oystercatcher Project
The
Black
Oystercatcher
is an endemic species of the rocky edge of the north Pacific from
Baja California to Alaska where it eats marine invertebrates and
nests on islets. The PWLF is collaborating with
Parks Canada
and
Laskeek
Bay Conservation Society
in a study to use changes in the ecology of the oystercatcher as a
signal of human impact in National Parks. Oystercatchers play an
important role in rocky shore intertidal communities as predators of
small
marine invertebrates.
They are largely confined to nest on small rocky
islets
away from most predators. Oystercatchers on islands
near urban centres are frequently disturbed by kayakers and boaters
and oil spills can harm oystercatchers.
Oystercatcher Discovery
The
objective of the Oystercatcher Discovery study is to measure
human impacts on the seashore. We selected the Black Oystercatcher
because it resides year round on a very small section of rocky shore
that it uses each year, it occurs on small islands visited by
boaters and kayakers, and its ground nest and flightless chicks
are vulnerable to human trampling. Oil spills can potentially be a
problem. We are surveying all the islands in the Strait of Georgia,
Broken islands and parts of the west coast of Vancouver Island,
including the seabird colony on Triangle island, and most of the
east coast of Moresby Island in Haida Gwaii (Queen Charlotte
Islands). This project is directed by Dr. Rob Butler from PWLF in
collaboration with colleagues from
Parks
Canada’s
Gulf
Islands National Park Reserve,
Pacific
Rim National Park Reserve
,
Gwaii
Hanaas National Park Reserve,
Laskeek
Bay Conservation Society,
and the
Canadian Wildlife Service.
Black Oystercatcher Project 2007 Update
In 2005 and 2006, a
collaborative census between the PWLF and Parks Canada staff
concluded that about 100 pairs of oystercatchers nested in the
Strait of Georgia. The details of this study will appear in an
upcoming issue of Northwest Science. The census results highlighted
the significance and sensitivity of nest sites and protection of
islets used for nesting which was adopted by the Gulf Islands
National Park Reserve conservation action in 2006.
In 2007, Parks
Canada’s Ecological Integrity Monitoring Program selected the
black oystercatcher as an indicator of rocky intertidal community
health. This decision provided impetus for Parks Canada to
collaborate on population surveys and associated research with
British Columbia, Alaska, Washington, Oregon and California agencies
as well as the PWLF and Laskeek Bay Conservation Society. The Black
Oystercatcher
Conservation Action Plan guides the efforts toward better
understanding of adult and fledgling survival, regional population
size and trends, seasonal movements of individuals and
inter-population mixing.
The field work in
2007 began to look at movements between populations and between
winter and summer habitats. Some birds received coloured leg bands
to help detect seasonal movements, nesting site fidelity and
inter-population dispersal. In addition to leg bands, satellite and
radio tracking devices were being used on birds in Pacific Rim
National Park and Alaska for collection of more detailed movement
data. Oystercatchers in Haida Gwaii have orange or dark blue bands
on the left leg. Pacific Rim and Clayoquot Sound birds wear white
with black letters on the right leg. In the Gulf islands, birds have
orange bands with black letters and on the southern BC mainland
coast, birds have yellow with black letters. Stay tuned for more
information on the black oystercatcher in the near future. We would
like to solicit your cooperation and effort in tracking these banded
birds. If you observe a banded bird, please note the band colour,
and number if visible, the name of the island of the sighting and
its geographic coordinates. You can send us that information by
clicking on Contact Us on the home page.
In the autumn of
2007, PWLF produced a short video entitled Tidecatchers that
will be broadcast on this web site soon.
Learn About Black Oystercatchers
Current PWLF Projects
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