Bird World › Ross's goose images › Great knot - Calidris tenuirostris
The great knot (Calidris tenuirostris) belongs to the family of sandpipers and knots, the Scolopacidae.The great knot is distributed in far northeast Russia, coastal Australia, southeast Asia, India, Bangladesh, Pakistan and eastern Arabian Peninsula. These knot species are listed as "Endangered" by IUCN. These knots are monotypic species.
Appearance, physical description and identification
The great knot (Calidris tenuirostris) is a large knot, measuring 25 to 30 cm in length and weighing 115 to 250 grams. The wingspan is 55 to 65 cm.The great knot has grayish upperparts with dark brown mottling. The head and breast have dark streaking. The underparts are white with scattered spotting. The wintering birds are paler.
The bill is medium-sized, thin and dark. The legs are short and grayish. The irises are dark brown. There is a pale eye-ring. Their call is a soft whistling, twittering sound.
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| 1.Bird World - Great knot - Calidris tenuirostris Image by Hiyashi Haka |
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| 2.Bird World - Great knot - Calidris tenuirostris Image by JJ Harrison |
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| 3.Bird World - Great knot - Calidris tenuirostris Image by Hiyashi Haka |
Origin, geographical range and distribution
The great knot is distributed in northeast Siberia (Russia), Australia, southeast Asia, Bangladesh, India (including Andaman and Nicobar Islands), Sri Lanka, Pakistan and the eastern Arabian Peninsula.Vagrant great knots have been recorded in USA, United Kingdom, Middle East, Spain, Norway, Netherlands, Ireland, Denmark and New Zealand.
The Important Bird and Biodiversity Areas (IBA) of these great knot species in UAE are Marawah Island, Khor Al Beidah and Khor Al Beidah. The IBA in Singapore are Ubin-Khatib and Ubin-Khatib. The IBA in Saudi Arabia is Tarut Bay.
The IBA in Russia are Rekinninskaya bay, Perevolochny bay, Ola lagoon, Moroshechnaya River, Malakchan bay, Khayryuzova bay and Babushkina and Kekurnyy Gulfs. The IBA in Malaysia is Sadong-Saribas coast.
Ecosystem and habitat
The great knot species does not normally occur in forest. It normally occurs in altitudes between 0 to 1600 meters.The artificial ecosystems and habitats of these species include coastal water storage tanks and coastal aquaculture facilities.
The natural ecosystems and habitats of these great knot species include subarctic grasslands, tundra grasslands, large lakes of Arctic region, marine lakes, mudflats, shorelines, estuaries and tide pools.
Diet and feeding behavior
The diet of the species consists mainly of plant matter like berries in the breeding grounds. Berries, insects, spiders, molluscs, crustaceans, annelid worms and echinoderms are their primary food during the winter and on passage.Reproduction and breeding habits
The breeding season of the great knot species is during subarctic summer in May and June. These birds are monogamous and territorial. The breeding habitat includes plateaux or gentle slopes with montane tundra.They nest in depression in moss. The clutch contains four eggs. The chicks hatch out after 22 days of incubation and fledge after 20 days. The male knot care for the hatchlings while the female moves southwards soon after hatching of the eggs.
Migration and movement patterns
The great knot species is fully migratory. The breeding populations occur in northeast Siberia (Russia). They migrate southwards in July, mainly to Australia for wintering, making several stopovers enroute.The wintering populations of the knot species are mainly distributed in Australia. The return migration to the breeding grounds occurs from March to April.
These knots also winter in the southeast Asian coastline, coasts of Bangladesh, India (including Andaman and Nicobar Islands) and Pakistan and the eastern coast of of the Arabian Peninsula (del Hoyo et al. 1996).
Great knot - Quick Facts
- Scientific name: Calidris tenuirostris
- Species author: (Horsfield, 1821)
- Synonyms/Protonym: Totanus tenuirostris Horsfield, 1821,
- Family: Scolopacidae › Charadriiformes › Aves › Chordata › Animalia
- Vernacular names: English: Great knot Chinese: 大滨鹬, French: Bécasseau de l’Anadyr, German: Großer Knutt, Spanish: Correlimos grande, Russian: Большой песочник, Japanese: ヒメハクガン
- Other names: Great Knot, Eastern Knot
- Distribution: Asia, Australia
- Diet and feeding habits: plant material, berries, insects, molluscs, crustaceans, worms
- IUCN status listing: Endangered (EN)
Conservation and survival
The global population size of the great knot (Calidris tenuirostris) is estimated to number about 292,000 to 295,000 individual birds (Wetlands International 2015). The overall population trend of the species is considered to be decreasing.In most of its range, this species is reported to be uncommon to rare. The generation length is 7.4 years. Its distribution size is about 1,920,000 sq.km.
Ecosystem degradation, ecosystem conversion, severe weather, climate change, loss of stopover habitats, oil exploration and pollution are the main threats that may endanger the survival of the species.
IUCN and CITES status
The great knot (Calidris tenuirostris) species has approached the thresholds for being Vulnerable under the range size criterion, under the population trend criterion and under the population size criterion.The IUCN (International Union for Conservation of Nature) has categorized and evaluated the knot species and has listed it as "Endangered".
The CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) status is ‘Not Evaluated’ for the great knot (Calidris tenuirostris).
| Taxonomy and scientific classification of Calidris tenuirostris | |
|---|---|
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Charadriiformes |
| Family: | Scolopacidae |
| Subfamily: | - |
| Genus: | Calidris |
| Species: | C. tenuirostris |
| Binomial name: | Calidris tenuirostris |
| IUCN status listing: |
 Endangered |
1.Great knot image source: https://www.flickr.com/photos/hiyashi/6959877850/in/photostream/ (cropped)
Author: Hiyashi Haka | License: CC BY-NC-SA 2.0 as on 10/30/18
2.Image source: https://en.wikipedia.org/wiki/File:Calidris_tenuirostris_-_Laem_Phak_Bia.jpg (cropped)
Author: JJ Harrison | License: CC BY-SA 3.0 as on 10/30/18
3.Image source: https://www.flickr.com/photos/hiyashi/7105946775/ (cropped)
Author: Hiyashi Haka | License: CC BY-NC-SA 2.0 as on 10/30/18
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Updated Oct 30, 2018
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