Great Thick-knee Esacus recurvirostris Scientific name definitions

41·5–54 cm (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ); c. 790 g; wingspan 90–100 cm. Large, massive thick-knee with proportions somewhat recalling bustard; unstreaked greyish upperparts ; face strongly patterned with white around and behind eye above black cheek patch and short malar stripe; bill massive, with more slender, uptilted tip and broad yellow base; in flight reveals largely black flight-feathers with striking white primary patches and broad pale grey band across median and greater upperwing-coverts, while feet scarcely project beyond tail (2 Hayman, P., J. Marchant, and T. Prater (1986). Shorebirds. An Identification Guide to the Waders of the World. Croom Helm, London, UK. Close ). No seasonal or sexual-based plumage variation (2 Hayman, P., J. Marchant, and T. Prater (1986). Shorebirds. An Identification Guide to the Waders of the World. Croom Helm, London, UK. Close ). Differs from somewhat similar E. magnirostris in white forehead, black rather than pale grey secondaries, and slightly more slender and pointed bill . Juvenile very similar to adult, but has buff fringes to upperparts feathers in fresh plumage.

SE Iran and from Pakistan through Indian Subcontinent (including Sri Lanka) to Indochina and Hainan (S China); perhaps also SW Afghanistan (confirmation needed).

Riverbed shingle and rocks, stony banks and mud (in preference to sand) around large lakes; sometimes visits nearby grassy flats when rivers flood . Infrequently on coastal beaches , sandy flats, tidal estuaries and saltpans; inhabits coastal district of dry zone in Sri Lanka, but restricted to undisturbed beaches. Recorded to 1300 m in Nepal (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ).

Sedentary, apart from local movements forced by rising water levels in rivers and lakes, and temporary changes in feeding conditions. Just one record from Goa, W India, attributed to a wandering bird (3 Borges, S.D. and Shanbhag, A.B. (2007). Additions to the avifauna of Goa, India. Journal of the Bombay Natural History Society. 104(1): 98–101. Close ), but some 18 in Oman, all in N of country and between late Oct and late Apr (4 Eriksen, J., and R. Victor (2013). Oman Bird List: the Official List of the Birds of the Sultanate of Oman. Seventh edition. Sultan Qaboos University, Muscat, Oman. Close ), with the first record in the United Arab Emirates a single first seen in Sept 2011 and again in Feb–Mar 2012 (5 Harrison, I. (2013). From the Rarities Committees. Sandgrouse 35(2):161–164. Close ).

Feeds mainly on crabs (e.g. Grapsus sp.) (3 Borges, S.D. and Shanbhag, A.B. (2007). Additions to the avifauna of Goa, India. Journal of the Bombay Natural History Society. 104(1): 98–101. Close ) and other crustaceans; also insects, and record of eggs of Kentish Plover (Charadrius alexandrinus). On oligotrophic reservoir, where crabs infrequent, young birds found to have eaten: young monitor lizard (Varanus) c. 21 cm long, intact but with head battered; whole shrew (Suncus stoliczkanus) c. 6 cm long; and small fish (Salmostoma bacaila) c. 8 cm long; also winged termites. Occasionally recorded stealing food from other birds. Mainly active after dusk, but sometimes feeds by day. Prises up stones with massive upcurved bill. Uses typical thick-knee feeding actions: wary and deliberate, walking slowly forward and tilting to take prey with large bill. Usually encountered alone or in pairs, more occasionally in family groups, and sometimes in flocks of up to c. 20 individuals (2 Hayman, P., J. Marchant, and T. Prater (1986). Shorebirds. An Identification Guide to the Waders of the World. Croom Helm, London, UK. Close ).

Gives somewhat wailing and accelerating series of whistles in territorial defence and display, comprising 2+ syllables with rising cadence, e.g. “tlueit, HLOOOEet, HWEEit, HWEIT-HWIT-HWIT-WIT-WIT-WIT-WIT-wit-wit-wit”, descending and dying away at end; most usually heard at night, by pair (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ); in alarm, utters loud, harsh-sounding “see-eek” (2 Hayman, P., J. Marchant, and T. Prater (1986). Shorebirds. An Identification Guide to the Waders of the World. Croom Helm, London, UK. Close ), or nervous “kree-ip”, singly or in loose series, sometimes becoming a rapid-fire series of “uit-uit-uit-uit-uit...” notes (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ). Display song differs from that of B. oedicnemus in being higher and ascending more strongly in pitch, and without dry trills and clicking notes, while compared to B. indicus, present species’ song starts slower and speeds up near end (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ).

Laying Feb–Jul in India, late Mar–Jun in Pakistan, mainly Apr–Jul in Sri Lanka; elsewhere, Mar in Bangladesh (6 Khan, M. M. H. (2005). Species diversity, relative abundance and habitat use of the birds in the Sundarbans East Wildlife Sanctuary, Bangladesh. Forktail 21:79–86. Close ) and early Jun in Laos (7 Thewlis, R. M., R. J. Timmins, T. D. Evans, and J. W. Duckworth (1998). The conservation status of birds in Laos: a review of key species. Bird Conservation International 8(Supplement):1–159. Close ). Monogamous. Territorial; sometimes breeds in colonies of River Terns (Sterna aurantia). Nest is scrape in ground on shingle bank, stony islet or on edge of lagoon in sparse grasses, usually close to water, lined with dry twigs (6 Khan, M. M. H. (2005). Species diversity, relative abundance and habitat use of the birds in the Sundarbans East Wildlife Sanctuary, Bangladesh. Forktail 21:79–86. Close ). Clutch 1–2 pale buff-coloured or creamy eggs with darker, browner or blacker markings (6 Khan, M. M. H. (2005). Species diversity, relative abundance and habitat use of the birds in the Sundarbans East Wildlife Sanctuary, Bangladesh. Forktail 21:79–86. Close ), mean size 54·4 mm × 41 mm (8 Robson, C. (2000). A Field Guide to the Birds of South-east Asia. New Holland, London, UK. Close ); incubation (28 days) and chick care (2 Hayman, P., J. Marchant, and T. Prater (1986). Shorebirds. An Identification Guide to the Waders of the World. Croom Helm, London, UK. Close ) by both sexes; chick has thick “pepper and salt” down with black speckles above, narrow brown stripes on head-sides and short mantle streaks (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ). No further information available.

Not globally threatened. Currently considered Near Threatened, mainly owing to precipitous declines in SE Asia. Apparently still locally common, forming small parties after breeding. Iranian population considered to number at least 25 pairs in 1970s, perhaps many more, but no recent comprehensive breeding surveys (9 Scott, D. A. (2007). A review of the status of the breeding waterbirds in Iran in the 1970s. Podoces 2(1):1–21. Close ). Scarce in Pakistan (where confined to Indus Valley) (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ) and in Bangladesh found mainly in the Sundarbans (6 Khan, M. M. H. (2005). Species diversity, relative abundance and habitat use of the birds in the Sundarbans East Wildlife Sanctuary, Bangladesh. Forktail 21:79–86. Close ); now very local throughout Indian Subcontinent (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ); no recent records from Thailand, where may have been extirpated, and has apparently undergone a signifcant decline in neighbouring Laos, from where there are very few recent records, all from the R Mekong and R Xe Kong (10 Evans, T.D. (2001). Ornithological records from Savannakhet province, Lao PDR, January–July 1997. Forktail 17: 21–28. Close ), although the species was common along the first-named river until at least the 1950s, with local people still collecting the species’ eggs (7 Thewlis, R. M., R. J. Timmins, T. D. Evans, and J. W. Duckworth (1998). The conservation status of birds in Laos: a review of key species. Bird Conservation International 8(Supplement):1–159. Close ) while hunting and incidental human disturbance are probably additional factors (10 Evans, T.D. (2001). Ornithological records from Savannakhet province, Lao PDR, January–July 1997. Forktail 17: 21–28. Close ). Record from SW Afghanistan (involving clutch of eggs) requires confirmation (1 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ), but was recently (2004) discovered breeding in lowlands of Bhutan (11 Spierenburg, P. (2005). Birds in Bhutan: Status and Distribution. Oriental Bird Club, Bedford, UK. Close , 12 Engel, J. (2016). Recent records from Bhutan, including the first records of Black-necked Grebe Podiceps nigricollis and Water Pipit Anthus spinoletta. BirdingASIA 25:47–49. Close ). Tolerant of altered habitats and colonizes reservoir edges; however, is generally rather wary, and requires large undisturbed areas for breeding.