| Water thick-knee | |
|---|---|
_close-up_(16608927739).jpg) | |
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| Head and habit of the nominate subsp. | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Charadriiformes |
| Family: | Burhinidae |
| Genus: | Burhinus |
| Species: | B. vermiculatus |
| Binomial name | |
| Burhinus vermiculatus (Cabanis, 1868) | |
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resident range | |
Thewater thick-knee orwater dikkop (Burhinus vermiculatus) is a species ofbird in the thick-knee familyBurhinidae. The species is found across sub-Saharan Africa, usually close to water.
The water thick-knee has a widespread distribution in sub-Saharan Africa, being found inAngola,Botswana,Burkina Faso,Burundi,Cameroon,Central African Republic,Republic of the Congo,Democratic Republic of the Congo,Eswatini,Ivory Coast,Ethiopia,Gabon,Ghana,Kenya,Liberia,Malawi,Mozambique,Namibia,Niger,Nigeria,Rwanda,Senegal,Somalia,South Africa,Tanzania,Uganda,Zambia, andZimbabwe.
Across its range it is found on the edges of lakes, estuaries and rivers, as well asmangroves and also some sheltered beaches. It also needs bushes or nearby woodlands for shelter. It is found from sea-level to 1,800 m (5,900 ft).[2]
There are two accepted subspecies:
_pair_with_chick_..._(53310850189)%2c_crop1.jpg)
The water thick-knee is 38 to 41 cm (15–16 in) and weighs 293–320 g (10.3–11.3 oz). It has a heavy bill that is black with some pale yellow from the nostril to the base. The wings are broad and blunt and the tail is short.[2] Its legs are pale greenish yellow, and the iris colour greenish yellow with black tracing.
The water thick-knee is a terrestrial feeder that forages at night. Although it is typically associated with water it can be found foraging up to 1 km (0.62 mi) from water. It feeds on insects, crustaceans and mollusks.[2]
The water thick-knee generally breeds in the dry season or early rainy season. It is a monogamous breeder with both parents guarding the nest and brooding the eggs. The nest is a simple scrape in sandy or stony ground, usually close to water. The clutch size is two sandy-yellow eggs. Both sexes incubate the eggs for 22-25 days, and both are responsible for feeding the young. Unique among birds, thick-knee pairs frequently nest adjacent to and sometimes directly on top ofNile crocodile nests. The two species share a form ofsymbiotic mutualism with the more energetic and vocal thick-knee functioning as loud sentries for the nests as the more powerful crocodile provides protection. Should a nest raider approach, the thick-knee pair will spread their wings in a threat display and harass and peck at the intruders to drive it off. If the pair not be successful, the mother crocodile will be drawn in by their continued calls and arrive.[2]
