Great Knot (Calidris tenuirostris)

Great Knot

[order] CHARADRIIFORMES | [family] Scolopacidae | [latin] Calidris tenuirostris | [UK] Great Knot | [FR] Becasseau de l’Anadyr | [DE] Grosser Knutt | [ES] | [NL] Grote Kanoetstrandloper

Subspecies

Monotypic species

Physical charateristics

Largest shorebird. Breast and flanks heavily spotted black. Scapulars with large chestnut spots and blackish tips. uppertail coverts mostly white.
Female averages larger, with less chestnut in scapulars. Non-breeding adult has paler grey upperparts and brest. Upperparts, head and neck finely streaked dark grey. Breast streaked, flanks lightly streaked.

Listen to the sound of Great Knot

[audio:http://www.aviflevoland.nl/sounddb/G/Great Knot.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.: 57 cm wingspan max.: 59 cm
size min.: 26 cm size max.: 28 cm
incubation min.: 21 days incubation max.: 22 days
fledging min.: 20 days fledging max.: 22 days
broods: 1   eggs min.: 3  
      eggs max.: 5  

Range

Eurasia : Northeast

Habitat

Habitat includes sheltered coasts with large intertidal mudflats and sandflats, inlets, bays, harbours, estuaries and lagoons.
Breeds in subarctic, on plateaux or gentle slopes with mountain tundra. In habitats ranging from gravelly areas covered by lichens and patches of herbs and heather to areas with continuous thick layer of lichen and scattered depressed larch or dwarf pine.

Reproduction

Egg laying in May-June. Monogamous and territorial and highly faithful to site. 4 eggs are laid in a single brood. Incubation lasts 21 days, by both parents but female leaves area after hatching, leaving male to care for chicks.
Chicks are mottled dull blackish brown above with some buff and with rows of white or cinnamon buff tips to down, underparts white to buffish white.

Feeding habits

Feeds mainly on bivalves, buried in soft sediment, also gastropods, crustaceans, annelids and sea cucumbers.
During breeding siason primarily plant material, mainly berries, also kernels of dwarf pine trees.
Feeds in large flocks, often in company of C. canutus, Limosa lapponica and H. brevipes. Nocturnal and diurnal forager.

Conservation

This species has been uplisted to Vulnerable owing to a rapid population decline caused by the reclamation of non-breeding stopover grounds, and under the assumption that further proposed reclamation projects will cause additional declines in the future.
Great Knot status Vulnerable

Migration

Long distance migrant, mainly along coast, probably with few stopovers. Females leave breeding grounds early Jul, males and young late Jul. N & S migration routes quite different. Most birds migrate via coast of Sea of Okhotsk (only on S migration), Ussuriland, South Korea (especially N migration), and E China (stopover, at least in N migration); straggler to New Zealand. Arrival in NW Australia late Aug and early Sept, 1st-year birds in Oct; Gulf of Carpentaria not reached until Dec; N migration occurs in Mar-Apr, and departure from NE Australia occurs late Mar to mid-Apr; probably flies non-stop to S China; arrival on breeding grounds late May to early Jun. Small numbers, with highest count 1193 birds, winter in or pass through Arabia, particularly Oman, United Arab Emirates and Saudi Arabia; birds wintering in Pakistan and India may cross Tibetan Plateau. Some 1st-years spend first boreal summer, and maybe longer, in non-breeding range, others migrate at least N to Sakhalin.

Distribution map

Great Knot distribution range map