Status of the Red Knot (Calidris canutus rufa) in the Western Hemisphere

• Other Authors: New Jersey Department of Environmental Protection (NJDEP), Division of Fish & Wildlife, Endangered & Nongame Species Program
• Format: Text
• Language: unknown
• Published: New Jersey Department of Environmental Protection (NJDEP), Division of Fish & Wildlife, Endangered & Nongame Species Program 2007
• Subjects: animals; beach; biology; birds; coastal zone; conservation; ecology; endangered species; environmental data; environmental monitoring; fisheries; invertebrates; rivers; threatened species; watershed; red knot; horseshoe crab; rufa; calidris canutus; migratory birds; Delaware Bay; Cape May Peninsula; Arctic; Cape May; Calidris canutus; Red Knot
• Online Access: http://www.state.nj.us/dep/fgw/ensp/redknot.htm; http://hdl.rutgers.edu/1782.1/rucore00000002110.Document.000062465

The population of the rufa subspecies of the red knot (Calidris canutus) has declined dramatically over the past twenty years. In 2002, population models showed that if adult survival remained low, rufa would go extinct within about ten years. Despite intensive studies, the reasons for the population decline and reduced adult survival are imperfectly known. The main identified threat is the reduced availability of horseshoe crabs (Limulus polyphemus) eggs in Delaware Bay arising from elevated harvest of adult crabs for bait in the conch and eel fishing industries. During northward migration, most rufa stopover in Delaware Bay where they feed mainly on the eggs of the horseshoe crabs and lay down fat and protein reserves both to fuel the 3,000 kilometer flight to the arctic breeding grounds and ensure their survival after they arrive at a time when food availability is often low. This study describes rufa in the context of worldwide red knot populations; assesses its status, its general natural history, its habitat, its breeding system, its migrations and its feeding ecology; and addresses the threats it faces and the conservation actions that may lead to its recovery. Prepared for U.S. Fish and Wildlife Service Purpose: To describe a subspecies of the red knot, rufa, in the context of worldwide red knot populations; assesses its status, its general natural history, its habitat, its breeding system, its migrations and its feeding ecology; and addresses the threats it faces and the conservation actions that may lead to its recovery.