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Monitoring Projects
Green Crab
Click here for an updated
report (November 2007) on the European
Green Crab situation in Commencement Bay.
This is a long-term project through a permit from Washington State
Department of Fish and Wildlife (WDFW). Since 2000, we have worked
with Naheeta Northwest and WDFW, placing crab (shrimp) pots on the
beach. Pot placement occurs monthly between April and September at
low tide, and we pick them up on the low tide cycle the next day and
document the benthic animals we catch.
We are looking for the European Invasive Green Crab, but we hope we
don't find them. The Green Crab was introduced via ships' ballast
from Europe to the Eastern Seaboard of the U.S, and from there to
San Francisco Bay. They have been spreading up the West Coast and
have been reported as far as Willapa Bay and Vancouver, B.C. These
creatures take over the habitat area they reside in, killing and
excluding the native species that once lived in that area.
When the Green Crab starts to inhabit an area, it will eat not only
the vegetation but also any creature smaller than itself. The result
of the Green Crabs' feasting is that the young Dungeness and Red
Rock crabs never grow up. The Green Crab has no natural predators
such as bacteria, viruses, or diseases to help control it, so
populations multiply quickly. In short, it decreases diversity and
destabilizes the natural balance of organisms wherever it is able to
find them. But since we are documenting all the wildlife found in
our pots, we will know which animals suffer if a Green Crab invasion
does occur and thus, which species will need to be restored.
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