Red Knot

Red Knot, adult breeding plumage

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Red Knot, adult non-breeding plumage

Red Knot juvenile

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1. Description
2. Sound
3. Conservation Status
4. Other Names
5. Cool Facts
6. Full detailed species account

The Red Knot is the largest of the "peeps" in North America, and one of the most colorful. It makes one of the longest yearly migrations of any bird, traveling 15,000 km (9,300 mi) from its Arctic breeding grounds to Tierra del Fuego in southern South America.

Description

• Large, bulky sandpiper.
• Relatively short, straight bill tapering to tip.
• Legs short and thick.
• Head and breast reddish in breeding plumage, gray the rest of the year.

• Size: 23-25 cm (9-10 in)
• Wingspan: 52-56 cm (20-22 in)
• Weight: 135 g (4.77 ounces)

Sex Differences

Sexes look similar.

Sound

Usually quiet away from breeding grounds, but may make a subdued, somewhat nasal whine that increases in strength and scale for about one second. Also a two-part "knuup-knuup" in flight. Display song is moaning, flutelike repeated "poorr-mee."

Conservation Status

Occurrence of large concentrations of knots at traditional staging areas during migration makes them vulnerable to pollution and loss of key resources. Numbers appear to be decreasing; the populations wintering in South America dropped over 50% from the mid-1980s to 2003.

Other Names

Bécasseau maubèche (French)

Cool Facts

• The Red Knot does not regurgitate undigested hard parts of prey, as do many species of birds. Instead it excretes the hard parts in the feces. Researchers have used fecal content to examine food consumption rates.

• Red Knots concentrate in huge numbers at traditional staging grounds during migration. Delaware Bay is an important staging area during spring migration, where the knots feed on the eggs of spawning horseshoe crabs. It is estimated that nearly 90 percent of the entire population of the Red Knot subspecies C. c. rufa can be present on the bay in a single day. The reduction in food available to the knots because of the heavy harvesting of horseshoe crabs may be responsible for a decline in Red Knot populations.

Sources used to construct this page:

1. Harrington, B. A. 2001. Red Knot (Calidris canutus). In The Birds of North America, No. 563 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
2. Morrison, R. I. G., R. K. Ross, and L. J. Niles. 2004. Declines in wintering populations of Red Knots in southern South America. Condor 106: 60-70.