Red knot (Calidris canutus) COSEWIC assessment and status report: chapter 1
COSEWIC
Assessment Summary
Assessment Summary – April 2007
Common name:
Red Knot
Scientific name:
Calidris canutus rufa
Status:
Endangered
Reason for designation:
This subspecies is a medium-sized shorebird that breeds only in Arctic Canada and migrates thousands of kilometres between its Arctic breeding grounds and wintering areas at the tip of South America. The subspecies has shown a 70% decline in abundance over the past three generations (15 years). It is threatened by a depletion of horseshoe crab eggs, a critical food source used during northern migration. There is no potential for rescue from other populations.
Occurrence:
Northwest Territories, Nunavut, British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Prince Edward Island, Nova Scotia, Newfoundland
Status history:
Designated Endangered in April 2007. Assessment based on a new status report.
Assessment Summary – April 2007
Common name:
Red Knot
Scientific name:
Calidris canutus roselaari type
Status:
Threatened
Reason for designation:
This designatable unit includes the subspeciesroselaari and two other populations that winter in Florida and northern Brazil and that seem to share characteristics ofroselaari. The subspecies roselaari migrates through BC and breeds in Alaska. The migration routes and breeding areas of the other two populations are unknown. This group has declined by 47% overall during the last three generations (15 years). Ongoing threats include habitat loss and degradation on wintering sites and, for the Florida/SE US and Maranhão groups, depleted levels of horseshoe crab eggs, a critical food source needed during northward migration. Rescue from other populations is not anticipated.
Occurrence:
Yukon, Northwest Territories, British Columbia
Status history:
Designated Threatened in April 2007. Assessment based on a new status report.
Assessment Summary – April 2007
Common name:
Red Knot
Scientific name:
Calidris canutus islandica
Status:
Special Concern
Reason for designation:
This subspecies is a medium-sized Arctic breeding shorebird that migrates to wintering grounds in Europe. Forty percent of the breeding population of this subspecies occurs in Canada. This subspecies has declined by 17% over the last three generations (15 years). There are no identified threats to individuals in Canada. Habitat on the Canadian breeding grounds is likely stable, but shellfish harvesting on the wintering grounds in Europe presents an ongoing threat.
Occurrence:
Northwest Territories, Nunavut
Status history:
Designated Special Concern in April 2007. Assessment based on a new status report.