The red knot is a medium-sized shorebird that breeds in the Arctic and migrates long distances to wintering grounds in the Southern Hemisphere. Their preferred habitat varies depending on the season and stage of their migration journey.
Breeding Grounds
The red knot breeds in the high Arctic tundra during the summer months of June and July. Their nesting areas are located in remote northern regions of Canada, Alaska, Russia, and Greenland. Red knots prefer flat, elevated tundra locations near bodies of water for breeding. This habitat provides open views to spot predators and access to food sources near shorelines.
Specific features of prime red knot breeding habitat include:
- Open, treeless tundra with low-growing vegetation like grasses, sedges, and heath
- Elevated dry patches of land for nesting
- Wetland areas nearby such as lakes, ponds, and tidal flats
- Access to coastal marine habitats like beaches, mudflats, and estuaries
- Abundant populations of invertebrates for food such as insect larvae, spiders, mollusks
- Limited human disturbance
Ideal conditions allow red knots to build well-concealed nests in vegetation clumps on dry tundra. Nearby waterbodies provide food sources like insect larvae, mollusks, and crustaceans. Coastal areas offer supplementary foods including marine worms, small clams, and shrimp-like creatures called amphipods.
Migration Stopover Habitats
During their long migrations between Arctic breeding areas and southern wintering regions, red knots stop to rest and feed in key habitats along coastlines. Prime stopover sites provide protection and abundant food to fuel up for their ongoing journey. Important migration stopover habitats include:
- Coastal wetlands – marshes, tidal flats, estuaries
- Beaches and mudflats
- Coastal inlets and lagoons
- Salt pannes
- River deltas
Red knots probe sand and mud for bivalves, gastropods, marine worms, crustaceans, and other small invertebrates. They prefer areas with good tidal flow and turnover to keep food items replenished. Dense concentrations of birds may gather at sites with especially rich food resources. Birds rest and roost on nearby sandy beaches and islands when not actively feeding.
Wintering Grounds
During the northern winter from November to February, red knots inhabit coastal wetlands, tidal flats, beaches, and lagoons along shores from the southeastern United States south to Argentina. Key wintering areas include:
- Lagoons along the Atlantic Coast of South America
- Caribbean islands
- Southern coastlines of the United States along the Gulf of Mexico and Atlantic
- Baja California and other western Mexico locations
Red knots favor habitats with soft substrates where they can probe for marine invertebrates. Prime food sources include small clams, snails, crustaceans, marine worms, and occasionally small fish. Birds may congregate in high numbers at sites with abundant food.
Habitat Threats
Several key threats put pressure on red knot habitats across their range:
- Climate change – Rising temperatures, sea level rise, and melting permafrost degrade Arctic nesting areas. Habitat loss along migratory routes also occurs due to climate impacts.
- Coastal development – Human activities like construction, resource extraction, pollution, and recreation disrupt red knot habitats.
- Overharvest of food sources – Commercial harvesting of horseshoe crab eggs makes an important food unavailable during migration stopovers.
- Disturbance – Human presence and activities like vehicles, hunting, fishing, and ecotourism can disturb feeding and roosting birds.
Conservation efforts to set aside protected coastal habitats, regulate human activity, and study food availability seek to safeguard red knot populations. Monitoring and managing key sites along their migratory flyway are vital for sustaining red knots across their range.
Conclusion
In summary, red knots rely on specific coastal wetland and shoreline habitats during their breeding season in the Arctic, migration stopovers, and wintering grounds. They require flat open terrain and soft substrates to safely nest, rest, roost, and probe for food. Conservation of these sensitive habitats across the red knot’s range is crucial as they face threats from climate change, human activity, and disruption of food sources. Protecting vital coastal sites and managing disruptions can help sustain red knot populations into the future.
References
Here are some references used to research this article:
- Audubon Guide to North American Birds – Red Knot species profile
- U.S. Fish & Wildlife Service Red Knot Background Information
- Environment Canada Red Knot Conservation Plan
- New Jersey Department of Environmental Protection – Red Knot Habitat
- Smithsonian Migratory Bird Center – Red Knot ecology