This important step marks at least a decade-long effort of warning and focused advocacy on behalf of the Red Knot. Since 2005, there have been four formal requests to list the Red Knot under the Endangered Species Act. Citing a lack of resources and other priorities, the USFWS opted not to list the species but, instead, placed it in the functional limbo of "candidate species" in 2006.
The USFWS noted that a primary factor in the recent decline of Red Knots has been reduced food supply in Delaware Bay resulting from an over harvesting of horseshoe crabs. The ability of Red Knots and other shorebirds to refuel and fatten up on horseshoe crab eggs during migratory stopovers during their journey from South America to their Arctic breeding grounds is critical to their survival.
The knot's population decline has been most dramatic since 2000. Scientists speculate that the species' breeding grounds in the Arctic have warmed, feeding areas on Delaware Bay, Cape Cod, and elsewhere have been impacted by rising sea levels and ocean acidification, and increasing temperatures have interfered with their lifecycles. For example, horseshoe crabs in Delaware Bay may be laying their eggs earlier than usual, thus leaving the migratory shorebirds with a shortfall when they reach this critical stopover site.
Although Threatened status is different from Endangered status, such a move could require states to adopt better regulatory mechanisms to limit horseshoe crab harvest, or the Service could additionally designate critical protected habitat for the shorebird, such as sand dunes for roosting or habitat areas which support prey.
|Red Knot by Tim Spahr|