Calidris canutus


Knots are medium-sized, short, stocky sandpipers which visit the UK in large numbers during winter, migrating from their Arctic breeding grounds. Commonly seen feeding in estuaries around the coast, the largest numbers can be seen at high tide roosts in the depths of winter. A long-distance migrant, the knot can travel up to 15,000 km, stopping along the way at least once to feed. Knots eat invertebrates, molluscs and crustaceans which they find by probing their bills in the mud and sand; special sensory organs in their bill tips help them to detect buried prey in a similar fashion to the way echolocation works in bats.

How to identify

The knot is fairly large and chunky with short, green legs. In winter they are silvery-grey on top and white underneath. In summer, they are brick-red underneath, with speckled, rust-brown upperparts. The bill is long, black and straight.

Where to find it

A very common winter visitor to our coast, gathering in very large numbers on muddy estuaries.


When to find it

  • August
  • September
  • October
  • November
  • December
  • January
  • February
  • March
  • April
  • May

How can people help

The winter population of knot is important in the UK but its coastal habitats are under threat from development, pollution and changing land use. To keep populations of wading birds healthy we need to ensure that our marine environment is managed properly. The Wildlife Trusts are working with fishermen, researchers, politicians and local people towards a vision of 'Living Seas', where marine wildlife thrives from coast to deep sea. Do your bit for our Living Seas by supporting your local Wildlife Trust.

Species information

Common name
Latin name
Calidris canutus
Wading birds
Length: 23-25cm Wingspan: 59cm Weight: 140g Average Lifespan: 7 years
Conservation status
Classified in the UK as an Amber List species under the Birds of Conservation Concern review.