Long-tailed nightjar
The long-tailed nightjar is one of 98 species of nightjar in the family Caprimulgidae, the "true nightjars". It is a nocturnal, insectivorous bird characterized by its distinctive long tail. It is found throughout mainland Africa in open areas, arid semi-deserts, and savannas, with common sightings alongside roadways.
Description
The long-tailed nightjar ranges from about 29–43 cm in size and is sexually dimorphic. It has a long, graduated tail, with its size ranging from 200-304 mm in males and 156-256 mm in females. Its plumage is primarily rufous-brown to gray-brown in colour, but has pale bands across the forewing, as well as along the trailing edge of the flight feathers. The males can also have a white throat patch and brown bills, legs and feet. A sexually immature Long-tailed Nightjar looks more similar to a female, however its plumage tends to be paler.The identification characteristics of the Long-tailed Nightjar are similar to those of the slender-tailed nightjar and the square-tailed nightjar. Specifically, when the long-tailed Nightjar is non-breeding or moulting, their tails can be shorter. However, these species can be distinguished as they tend to occur in non-overlapping geographic areas and also have different songs. The song of the Long-tailed Nightjar is composed of a rapid, higher-pitched and sustained churring, at a frequency of about 42–43 units per second, which is much quicker than both the Slender-tailed Nightjar and the Square-tailed nightjar. In regions where the slender-tailed nightjar's range geographically overlaps with that of the Long-tailed Nightjar, the two can be distinguished as the long-tailed nightjar's plumage is relatively more red in colour.
The moulting pattern in which the long-tailed nightjar replaces its primary feathers is a typical strategy amongst nightjars, where the primaries are replaced in a descendant manner. However, its secondaries moult in a relatively unusual manner, with two moult centres. One moult centre begins with the outermost secondary feather and moults in an ascendant manner towards the fifth secondary, whereas the second moult centre begins with the ninth secondary and follows a centrifugal moult pattern. The moult duration has been estimated to take approximately 70 days. The moult tends to arrest in the mid-winter.
Taxonomy and systematics
Diversity within nightjar species, including the long-tailed nightjar, tends to be high both genetically and morphologically, resulting in many subspecies. There are three recognized geographically distinct subspecies of Long-tailed Nightjar, C. c. climacurus, C. c. sclateri and C. c. nigricans. The subspecies C. c. climacurus can be found from Mauritania to Sudan, eastern Congo and western Ethiopia. C. c. sclateri can be found from Guinea to northwestern Uganda. C. c. nigricans can be found in eastern Sudan and Ethiopia in the Nile Valley. C. c. sclateri has relatively darker and redder plumage, with its tail being dark brown on top and black below. C. c. nigricans has overall very dark plumage, with distinct black colouration on its upper parts interpolated with white specks. Recent reconstructions of the nightjars' phylogeny indicate that the long-tailed nightjar is most closely related to the Square-tailed Nightjar. C. climacurus, alongside C. fossii and C. clarus, were previously classified under a separate genus, known as Scotornis.Habitat and distribution
The long-tailed nightjar is found in the Afrotropical realm in multiple African countries including Angola, Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Eritrea, Ethiopia, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Kenya, Liberia, Mali, Mauritania, Niger, Nigeria, Senegal, Sierra Leone, Sudan, Tanzania, Togo and Uganda. It is found mainly in open areas of the northern Afrotropics. This includes roadsides, savannas, semi-arid deserts and lowland forest clearings. It can often be found in the company of the standard-winged nightjar.Behaviour and ecology
Reproduction
The laying season of the long-tailed nightjar varies depending on geographic location. The laying season is from March to September in Gambia and Senegal, May to August in northern Nigeria, January to October in southern Nigeria, March to August in Mali, March to June in northeastern Congo and February to April or April to June in eastern Africa.No nest is built for the eggs, rather a clear patch of land, approximately 4 x 5 cm in size, is chosen. Nest locations include bare land, open soil, sand, clear patches between pebbles or leaf-litter, beside pathways, in a thicket or under small bushes in fields. The clutch size is typically two eggs. The eggs are ellipsoidal in shape, matte in finish and colouration varying from whitish, cream, buff or pinkish – typically matching the ground colour. Additionally, grey, grey-purple and chestnut brown blotches and thick marbling fill in the egg's surface, further aiding with camouflage.The incubating bird tends to rest flat on top of the eggs with its eyelids closed.