Nightjars (Caprimulgidae)
Nightjars
(Caprimulgidae)
Class Aves
Order Caprimulgiformes
Suborder Caprimulgi
Family Caprimulgidae
Thumbnail description
Small to medium-sized nocturnal and crepuscular birds with small bill, large gape and eyes, long wings and tail, short legs, cryptic coloration, and comb-like serrations on the claw of middle toe
Size
6–16 in (15–40 cm); 0.7–6.6 oz (20–188 g)
Number of genera, species
19 genera; 77 species
Habitat
Semi-desert, grassland, savanna, woodland, and forest
Conservation status
Critically Endangered: 2 species; Endangered: 2 species; Vulnerable: 3 species; Near Threatened: 4 species
Distribution
Nearly cosmopolitan, but absent from Arctic, Antarctic, and most oceanic islands
Evolution and systematics
Fossils of a single undescribed species of Caprimulgidae have been reported from the Middle Eocene (50.5–42 million years ago) oil shales at Messel in Germany, providing the only fossil record of a true nightjar from the Tertiary. Other fossils suggest that the closest relatives of the nightjars, the potoos (Nyctibiidae) and frogmouths (Podargidae), had diverged by the Eocene, and estimates based on differences in their DNA structures likewise point to early Tertiary origins of the nightjars.
Division of the Caprimulgidae into two subfamilies, the nighthawks (Chordeilinae) and nightjars (Caprimulginae), is based on several characters, of which the absence of rictal bristles in nighthawks is the most obvious (the rictus is the gape of a bird's mouth). Compared to the nightjars, nighthawks tend to have longer wings and tail and more often have a notched or forked tail, but there are exceptions. Originally, the Chordeilinae was established only for several American genera of nighthawks, but the African brown nightjar (Veles binotatus) and the Asian to Australasian eared nightjars (genus Eurostopodus) show similar characters, so these also should probably be included in the Chordeilinae. However, the so-called nacunda nighthawk (Podager nacunda) has well-developed rictal bristles and other characters like those of the true nightjars, so it seems best placed in the Caprimulginae.
The elaborately lined plumages of nightjars differ little between some species, yet other species are variable in color. It is therefore often difficult to classify nightjars into species and there is a tendency to rely on differences in songs and other evidence in seeking the best possible treatment, especially when similar forms occur in neighboring regions without range overlap. Such unsolved problems in the classification of species exist with the African fiery-necked nightjar (Caprimulgus pectoralis) and the closely related black-shouldered night-jar (C. nigriscapularis), which differ very slightly in appearance and have slightly different songs. Likewise, treatment of the eastern and western American forms of the whip-poor-will (Caprimulgus vociferus) as subspecies of a single species remains tentative because they are very similar in coloration but have slightly different voices.
Physical characteristics
Nightjars are small to rather large Caprimulgiformes with a relatively large head, large eyes, short neck, and very short legs. Although the bill is tiny, the huge gape allows large insects to be swallowed whole. The base of the bill often has strong rictal bristles (lacking in Chordeilinae), which may serve to direct prey into the gape, to protect the eyes from hard prey, or both. Wings are long to very long and more or less pointed, and the tail can be rather short to long with a graduated, rounded, square, notched, or forked tip. Toes are slender, and the claw of the middle toe has comb-like serrations that provide a unique feature of the Caprimulgidae within the order Caprimulgiformes.
A few species have elaborate long plumes that probably serve to exaggerate displays. In three South American species
of the genus Macropsalis, adult males have deeply forked tails with greatly elongated outer feathers, which converge at their tips in the swallow-tailed nightjar (M. segmentata) and long-trained nightjar (M. forcipata) but converge subapically then diverge slightly at the extreme tips in the lyre-tailed night-jar (M. lyra). Adult males of two African species develop a single greatly elongated inner secondary feather that is retained only for part of each year. In the standard-winged nightjar (Macrodipteryx longipennis) the elongated feather consists only of a wire-like shaft except near the tip where it widens into a broad standard so that when the bird flies it seems to be closely followed by two large dark butterflies. The closely related pennant-winged nightjar (M. vexillarius) has the inner secondary modified to form a long narrow streamer. The exaggerated display plumes of the genera Macropsalis and Macrodipteryx appear to be associated with lek displays (a lek is a mating ground) in these species, which are the only polygynous (more than one female mate at a time) nightjars.
Nightjar plumages are marked in mainly somber shades of brown, gray, buff, tawny, or rufous and are often beautifully patterned with bars, streaks, and blotches to give some of the finest examples of concealing coloration of any animals. Thus, desert birds such as the aptly named golden nightjar (Caprimulgus eximius) tend to be pale to match the prevalent substrate, whereas birds of the dark forest interior such as the brown nightjar are predominantly very dark brown or blackish. White or pale signal markings used in nightjar displays are normally kept concealed inside closed wings or tail or beneath the throat when the birds are at rest; they are revealed during nocturnal display flights or when singing.
Distribution
The range of caprimulgids is much wider than that of any other family in the order Caprimulgiformes, and many of the species are migratory, unlike the essentially sedentary birds in other families. Only the Arctic, Antarctic, and remote oceanic islands lack nightjars. The greatest diversity of species occurs in the tropics and subtropics. In North America the common nighthawk (Chordeiles minor) extends far north into Canada. In the Old World the European nightjar (Caprimulgus europaeus) extends north to the boreal forests of Finland and east to the semi-desert steppes of Mongolia. In the Southern Hemisphere, the band-winged nightjar (Caprimulgus longirostris) ranges south to Chile.
The diet of flying insects prevents most nightjars from remaining all year in regions with cold winters, although the common poorwill (Phalaenoptilus nuttallii) does so by hibernating. Other species that breed at high latitudes are long-distance migrants, the most striking examples being the common nighthawk, which leaves North America to winter in South America as far south as northern Argentina, and the European nightjar, which leaves Europe and Asia to winter in Africa south of the Sahara. Shorter migrations are under-taken by species such as the red-necked nightjar (Caprimulgus ruficollis), which breeds in Spain and winters south of the Sahara in west Africa, and the rufous-cheeked nightjar (C. rufigena), which breeds in South Africa and neighboring countries but migrates to spend the southern winter in tropical and subtropical countries of central Africa, especially Cameroon. Other species make seasonal movements from one vegetation zone to another within the tropics.
Habitat
Nightjars and nighthawks occupy a much broader range of habitats than do members of other families of Caprimulgiformes, which are often closely restricted to the ancestral rainforest habitats of the order. Instead of requiring trees for nest sites and hunting perches, the Caprimulgidae have evolved a predominance of ground nesting, and many species have the ability to hunt in sustained flight or by sallying from the ground, which enables them to live in grasslands, steppes, semi-deserts, savannas, and open woodlands. Few nightjar and nighthawk species live in closed forests, including both lowland and montane rainforests, and it is likely that species inhabiting such forests have reinvaded from more open habitats.
Several species have become urban dwellers, finding suitable nest sites on flat roofs of city buildings and plenty of insects to hunt around street lights and high in the air. Common nighthawks have adopted many North American cities over
the twentieth century, and band-winged nightjars have colonized Rio de Janeiro (Brazil), Madagascar nightjars (Caprimulgus madagascariensis) occur in towns in Madagascar, and savanna nightjars (C. affinis) are at home in such large Indonesian cities as Jakarta and Surabaya.
Behavior
Like other Caprimulgiformes, nightjars and nighthawks are essentially crepuscular and nocturnal birds that sit quietly in roosts during the day and become active from around dusk until dawn. The timing of activities varies among species, season, and sometimes according to phase of the moon. The common nighthawk begins feeding much earlier in the evening than most nightjars, often hunting in the last of strong daylight well before dusk. Other species commonly remain immobile until little light is left and human observers can scarcely distinguish colors in the twilight; the late start to activity presumably serves to reduce risks of predation. Many nighthawks and nightjars do not hunt during the middle hours of moonless nights, apparently because they are unable to see prey when there is insufficient light; this hypothesis seems to be confirmed by the fact that some feed for much longer on moonlit nights.
Common poorwills are able to become torpid and hibernate for months in a rock crevice during cold winter conditions, but there is no evidence that any other species of the family makes such extensive use of torpor. Nevertheless, torpor lasting at least several hours has been reported from common nighthawks, lesser nighthawks (Chordeiles acutipennis), and European nightjars that were cold, hungry, or both. It seems likely that entering torpor to reduce energy requirements is among the adaptations of Caprimulgidae that enable them to cope with an uncertain food supply.
Most nightjars have striking territorial songs that vary from clear loud whistles or whistled phrases to sustained churring, knocking, or purring sounds. The name nightjar derives from the prolonged jarring chur of the European nightjar, and the nocturnal vocalizations provide the first indication of the presence of most nightjar species for layman and ornithologist alike. Besides the song, the vocabulary of several of the better-known species includes a range of calls. The European nightjar uses at least 10 different types of calls, among which are special flight, alarm, threat, mating, brood-summoning, and food-begging calls. Mechanical wing clapping is also a feature of territorial display in the European nightjar and many other species.
Feeding ecology and diet
The diet of nightjars and nighthawks consists largely of insects. It typically includes beetles, moths, bugs, orthopterans, flies, termites, and flying ants, most if not all of which are caught in flight. Some nightjars take a small proportion of food from the ground or pick it from vegetation while hovering, and this behavior doubtless accounts for occasional wingless beetles, ants, or caterpillars that are eaten. Besides insects, spiders are occasionally eaten and there are a few records of centipedes, millipedes, and small snails in nightjar stomach contents. The rare records of seeds and other vegetable matter, however, may represent material accidentally ingested along with insects. The largest of all the nightjars, the chuck-will's-widow (Caprimulgus carolinensis), rarely eats tree frogs and very small birds, mainly warblers (Parulidae).
Two principal feeding techniques are used by nightjars and nighthawks, both of which lead to seizing prey in the bill while in flight and swallowing it whole. Hawking involves sustained flights during which the bird may catch numerous insects, often high in the air, but sometimes also low over the ground or water. Sallying involves a shorter flight from a perch or from the ground to catch an insect before returning to a perch. Most nighthawks and some nightjars rely almost exclusively on hawking for food, their long wings and strong flight evidently being adaptations for this. On the other hand, many nightjars of wooded or forest habitats rely mainly or exclusively on sallying. Others use both techniques. The European nightjar apparently chooses between them according to abundance and location of prey.
Because most feeding takes place in near-darkness, there has been much misunderstanding of how it is carried out. Many old accounts implied that nightjars fly about with the bill open, using it in the manner of a net to scoop up insects. This may occasionally be true, as when the bird flies through dense swarms of tiny insects such as mosquitos, but it is not the usual technique. Detailed studies of common nighthawks, common poorwills, and European nightjars show that individual insects are targeted and the bird only opens its bill to
seize them when they are closely approached. There seem to be clear preferences for larger insects, and limitations of the birds' eyesight may preclude feeding on the smallest prey (as opposed to considerations of cost-effectiveness).
Nightjars are adept at locating concentrations of insect prey and taking advantage of local superabundances of insects. Swarms of winged ants and termites, emerging caddis-flies, and mayflies at lakes may be targeted. Concentrations of insects around streetlights provide attractive food sources and artificial light may allow feeding later into the night than is possible under natural conditions. Nightjars also feed on insects flushed by grass fires in savanna regions of Africa and in open pine forests of the southeastern United States.
Reproductive biology
Most nightjars are monogamous, with pairs mating for life or breeding together for one season. Occasionally they may change partners between clutches in the same season. The pennant-winged and standard-winged nightjars have a different breeding strategy from other nightjars and are probably polygynous.
Breeding seasons of Caprimulgidae appear to be timed to coincide with presence of abundant flying insects needed to feed young. Species with northern ranges, such as common nighthawks or European nightjars, are rather late arriving as spring migrants and do not lay eggs until late spring. In tropical savannas, breeding typically occurs as the flush of new vegetation following seasonal rains allows a peak of insect abundance. The breeding season may be more prolonged in regions of the tropics with rain for much of the year, although caprimulgids usually avoid breeding in the months with high rainfall.
Unlike several other families of Caprimulgiformes, none of the nighthawks or nightjars makes a nest. Most choose a simple hollow in the ground, apparently without deliberately deepening it. A few species nest in depressions in tree branches, high above the ground in the case of short-tailed nighthawks (Lurocalis semitorquatus). The only account of the nest of the brown nightjar was of a bird apparently incubating or brooding on top of an arched frond of a Raphia palm in the Central African Republic. Nesting above ground is rare in Caprimulgidae and is apparently a secondary development from ground nesting, as no nest-building or other special adaptations are known to be involved.
Clutches are of one or two eggs, typically a single egg in tropical species and two eggs or variably one or two in others. Eggs are unmarked white in some species (for example most eggs of common poorwills), but more often they are spotted or blotched with shades of brown, gray, lavender, or black, which promotes concealment. Nevertheless, it is likely that there is little need for concealing coloration with eggs of most nighthawks and nightjars because an incubating adult bird would normally cover them almost continuously.
The role that males and females play in incubation varies considerably among species. In freckled nightjars (Caprimulgus tristigma) and fiery-necked nightjars, males incubate at night and the more cryptically colored females do so by day. In European nightjars, the male takes only a short stint at dusk and dawn while the female is away feeding. In polygynous pennant-winged and standard-winged nightjars, only the female incubates eggs. Incubation periods are unknown for many species, but typically they last about 17–20 days.
Young hatch with a covering of soft down that is replaced by the emerging juvenal feathers after about a week. Small
young in down are brooded most of the time, but when they grow juvenal feathers they are typically brooded only when it is cold or wet. Even quite small young commonly walk from the original nest site and after a few days they may be many yards away from it. Fledging is a gradual process in that development of flying skills is progressive, with weak flapping usually possible after about two weeks but strong flight and independent feeding not until the fourth week. Typically, both parents are involved in brooding the young and feeding them on regurgitated insect food, but only the female carries out these duties in polygynous species.
Several of the nightjars are known to raise two broods each breeding season, and most if not all will lay replacement clutches if the first is lost. The two broods in European night-jars somewhat overlap, a response to the short northern breeding season. This is achieved because the male takes full charge of the young of the first brood while the female incubates the second clutch.
Many nightjar eggs and young are lost to predators, including birds such as crows, mammals such as rats and mice, and snakes. Much of the breeding behavior of nightjars is adapted to reduce risks of predation. For example, incubating birds crouch motionless with eyes almost closed, unwilling to leave the nest until almost trodden upon. When detected at the nest, adult nighthawks and nightjars commonly show threat or distraction displays intended to intimidate or distract potential predators. These displays have been well studied in lesser nighthawks; ground predators or less dangerous intruders such as sheep or rabbits are confronted with a threat display in which the bird faces the intruder, erects its plumage with spread wings and tail, and at high intensity gapes and hisses. Walking humans or crows are met with distraction displays of disablement-lure type, in which the adult bird typically flutters along the ground as if injured, with trailing wings or flopping flight, attempting to lure the intruder away from eggs or chicks.
Conservation status
Two nightjar species are Critically Endangered: Jamaican poorwill (Siphonorhis americana; last reliably recorded in 1859) and Puerto Rican nightjar (Caprimulgus noctitherus). Two species are Endangered: white-winged nightjar (C. candicans) and Itombwe nightjar (C. prigoginei). Three species are listed as Vulnerable: Heinrich's nightjar (Eurostopodus diabolicus), Bonaparte's nightjar (C. concretus), and nechisar nightjar (C. solala). Four species are classified as Near Threatened: Salvadori's nightjar (C. pulchellus), sickle-winged nightjar (Eleothreptus anomalus), Chocó poorwill (N. rosenbergi), and plain-tailed nighthawk (Nyctiphrynus vielliardi). An additional three species are listed as Data Deficient.
Significance to humans
No nightjar species is of much economic importance and many of them are retiring birds that are little known to local people. However, their strange and often beautiful nocturnal
voices attract attention, and several species are the subject of folklore. A recurrent theme is the myth that nightjars suck milk from the teats of goats, resulting in widespread use of names such as goatsucker in English, Ziegenmelker in German, and Succiacapre in Italian. The scientific name of the principal nightjar genus, Caprimulgus, has the same origin, being formed from the Latin words capra for a goat and mulgere to milk. The basis for this groundless belief may lie in the frequent observation of milk on the ground near goats with newly-born kids coupled with presence of nightjars feeding on insects near the animals at night and the fact that night-jars have an immensely wide mouth.
Other widespread beliefs are that the nocturnal calls of various nightjars are bad omens that may even foretell death. One local name for the European nightjar, the German Todtenvögel, means death bird. Elsewhere, the number of successive calls given by some South American nightjars was believed to foretell the number of years for which the listener would live, and other nightjar species were thought to represent spirits of the dead.
Species accounts
List of Species
Common nighthawkSpotted nightjar
Common poorwill
Chuck-will's-widow
Whip-poor-will
Gray nightjar
European nightjar
Large-tailed nightjar
Fiery-necked nightjar
Standard-winged nightjar
Common nighthawk
Chordeiles minor
subfamily
Chordeilinae
taxonomy
Caprimulgus minor J. R. Forster, 1771, South Carolina. Nine subspecies.
other common names
English: Nighthawk, American or booming nighthawk; French: Engoulevent d'Amérique; German: Falkennachtschwalbe; Spanish: Añapero Yanqui.
physical characteristics
8.7–9.7 in (22–25 cm); 1.4–3.8 oz (40–107 g). Dark brown, buff, grayish white, and cinnamon cryptic coloration. Sexually dimorphic.
distribution
Breeds over much of North and Central America from Canada to Panama; winters in South America from Ecuador to northern Argentina.
habitat
Mainly in open habitats, including woodland clearings, prairies, savannas, sand dunes, and cities.
behavior
Active from well before dusk until after dawn, often flying high in air. Commonly in flocks outside breeding season, sometimes of up to a thousand birds. Displaying male makes booming sound as air rushes through primaries during aerial dive.
feeding ecology and diet
Catches diet of insects mainly on wing during continuous hawking flight; regularly takes insects that have been attracted to street lights.
reproductive biology
Unlined nest site on ground (or flat roof of building) with clutch of two eggs. Incubation usually by female for a period of 18–20 days. Young have cryptically patterned down, are fed by both parents, and fledge at 25–30 days.
conservation status
Not threatened.
significance to humans
More often noticed by humans than most other nightjars in North America because of habit of nesting on flat roofs of buildings in towns and cities and activity and calls during twilight or even daylight.
Spotted nightjar
Eurostopodus guttatus
subfamily
Chordeilinae
taxonomy
Eurostopodus guttatus Vigors and Horsfield, 1826, New South Wales. Monotypic.
other common names
English: Spotted eared-nightjar; French: Engoulevent argus; German: Argusnachtschwalbe; Spanish: Chotacabras Argos.
physical characteristics
11.5–13.2 in (29–33 cm); 2.8–3.7 oz (80–104 g). Grayish brown, grayish white, tawny, and buff cryptic coloration. Sexes are similar.
distribution
Breeds over much of Australia west of the Great Dividing Range; winters mainly in north of breeding range, but migratory stragglers recorded from islands north of Australia.
habitat
Open woodlands, grasslands.
behavior
Roosts on ground during daytime; active from dusk until before dawn. Musical song advertises territories. Song commences with two to five up-slurred units then concludes with eight to 15 higher-pitched clinking double units, all on the same pitch.
feeding ecology and diet
Feeds on insects, mainly caught in sustained hawking flight over the territory after dusk and before dawn.
reproductive biology
Nest is an unlined scrape in ground with clutch of single egg. The egg is greenish with dark spots. Small young have reddish brown down. Incubation apparently by both sexes, period unknown. Young can flutter short distances after 18–20 days.
conservation status
Not threatened.
significance to humans
A retiring nocturnal bird of the Australian outback, unfamiliar even to most country dwellers except by its nocturnal calls. According to the superstition of some Australian aboriginals, this species took away babies during the night.
Common poorwill
Phalaenoptilus nuttallii
subfamily
Caprimulginae
taxonomy
Caprimulgus nuttallii Audubon, 1844, eastern side of the upper Missouri River. Five subspecies.
other common names
English: Poorwill; French: Engoulevent de Nuttall; German: Winternachtschwalbe; Spanish: Chotacabras Pachacua.
physical characteristics
6.7–8.7 in (17–22 cm); 1.1–2.0 oz (32–58 g). Grayish brown, grayish white, blackish brown, and buff cryptic coloration. Sexes marginally dimorphic.
distribution
Breeds in western North America from southern Canada to northern Mexico, leaving northern part of range for winter.
habitat
Open woodland, scrub, prairies, canyons.
behavior
Roosts on bare ground during day, becoming active from around dusk until before dawn. May become torpid and hibernate in rock crevice for months during winter. Song sounds like "poor-will-ip."
feeding ecology and diet
Catches insect prey mainly on short sallying flights from low perch or ground.
reproductive biology
Unlined nest on ground with clutch of two unmarked, white eggs. Incubation period 20–21 days; both sexes incubate. Small young have vinaceous-buff down with dark markings. Young make first flight at 20–23 days old.
conservation status
Not threatened.
significance to humans
Living birds poorly known even to local people. Species has become famous among ornithologists as best example of a bird that hibernates.
Chuck-will's-widow
Caprimulgus carolinensis
subfamily
Caprimulginae
taxonomy
Caprimulgus carolinensis Gmelin, 1789, South Carolina. Mono-typic.
other common names
English: Carolina chuck-will, chuck; French: Engoulevent de Caroline; German: Carolinanachtschwalbe; Spanish: Chotacabras de la Carolina.
physical characteristics
11–23 in (28–33 cm); 3.3–5.2 (94–147 g). Brown, blackish brown, buffish white, and white cryptic coloration. Sexually dimorphic.
distribution
Breeds in eastern and southeastern USA; winters from Florida and West Indies through Central America to Colombia and northern Venezuela.
habitat
Woodland and forests. Often sits and calls at night from gravel roads.
behavior
Roosts during day; active mainly at dusk and before dawn. Song "chuck willow willah" is basis of English name, the initial "chuck" is often inaudible.
feeding ecology and diet
Feeds mainly on insects caught on sallying flights from ground or perch. Occasionally recorded feeding on small birds.
reproductive biology
Unlined nest on ground with clutch of two eggs that are cream with dark blotches and spots. Incubation by female for period of around 20 days. Small young are golden-brown, paler beneath. Young can fly when 16–17 days old.
conservation status
Not threatened.
significance to humans
Rarely noticed by humans, except for its distinctive nocturnal song.
Whip-poor-will
Caprimulgus vociferus
subfamily
Caprimulginae
taxonomy
Caprimulgus vociferus Wilson, 1812, eastern United States. Six subspecies.
other common names
French: Engoulevent bois-pourri; German: Schwarzkehlnachtschwalbe; Spanish: Chotacabras Cuerporruín.
physical characteristics
9–10 in (23–26 cm); 1.5–2.4 oz (42–69 g). Grayish brown, blackish brown, tawny, buff, and whitish cryptic coloration. Sexually dimorphic.
distribution
Breeds in eastern North America from southern Canada southwards, in Cuba, and in Central America south to Honduras; migrates from northern part of range for winter.
habitat
Forests and open woodlands.
behavior
Roosts during day; active from dusk until before dawn. Distinctive nocturnal song "whip' poor weel'" is basis of English name.
feeding ecology and diet
Feeds on insects caught in flight, often on short sallying flights from a perch.
reproductive biology
Unlined nest on ground with clutch of two eggs. Eggs are white to pale cream, usually with spots or small blotches of gray and brown. Incubation mainly by female for period of 19–20 days. Small young have pale buff to yellowish brown down. Young can first fly when about 20 days old.
conservation status
Not threatened.
significance to humans
Rarely noticed by humans, except for its distinctive nocturnal calls.
Gray nightjar
Caprimulgus indicus
subfamily
Caprimulginae
taxonomy
Caprimulgus indicus Latham, 1790, India. Five subspecies.
other common names
English: Japanese, jungle, or migratory nightjar; French: Engoulevent jotaka; German: Dschungelnachtschwalbe; Spanish: Chotacabras de Jungla.
physical characteristics
8.3–11.4 in (21–29 cm); 2.4–3.8 oz (69–107 g). Grayish brown, blackish brown, buff, tawny, brown, and grayish white cryptic coloration. Sexually dimorphic.
distribution
Breeds in southern and eastern Asia from India to northeast China and Japan; northern populations migrate to winter south to Java.
habitat
Open forests, woodlands, scrub, and farmland.
behavior
Roosts during day; active mainly at dusk and before dawn. Territorial song a long series of rapidly repeated knocking sounds.
feeding ecology and diet
Catches insect prey in sustained hawking flight and by shorter sallying flights from perches.
reproductive biology
Unlined nest on ground with clutch of two eggs. Eggs are white, pale cream, or pale gray, marbled with dark brown or grayish, with overlying spots of clear gray. Incubation mostly
by female, for period of 16–17 days. Small young have tawny down. Fledging period probably about 18 days.
conservation status
Species is not threatened, but endemic subspecies in Palau Islands is uncommon and declining.
significance to humans
Infrequently noticed by local people, except for nocturnal songs.
European nightjar
Caprimulgus europaeus
subfamily
Caprimulginae
taxonomy
Caprimulgus europaeus Linnaeus, 1758, Sweden. Six subspecies.
other common names
English: Common goatsucker; French: Engoulevent d'Europe; German: Ziegenmelker; Spanish: Chotacabras Europeo.
physical characteristics
10–11 in (25–28 cm); 1.2–3.6 oz (35–101 g). Grayish brown, blackish brown, buff, brown, and whitish cryptic coloration. Sexually dimorphic.
distribution
Breeds across most of Europe and North Africa and east across Asia to Outer Mongolia; all populations migrate to winter in Africa south of Sahara.
habitat
Breeds in open woodland, heath, sand dunes, steppe, and semidesert; winters in savannas and woodlands.
behavior
Roosts during daytime; active from before dusk until dawn. Prolonged churring song serves to advertise territory. Song is a sustained tremolo, alternating between lower-pitched screeches and slower, higher-pitched screeches, and ending in a quiet bubbling trill, the whole often lasting five minutes.
feeding ecology and diet
Catches insect prey in sustained hawking flights or in short sallying flights from perches.
reproductive biology
Unlined nest on ground with clutch of two eggs. Eggs are pale gray to cream with dark blotches and spots. Incubation mainly by female for 17 days. Small young have cream-buff down. Young tended by one or both parents; able to fly when about 17 days old.
conservation status
Not globally threatened, but declining in some European countries such as Ireland.
significance to humans
Infrequently noticed by local people, except for its churring nocturnal song.
Large-tailed nightjar
Caprimulgus macrurus
subfamily
Caprimulginae
taxonomy
Caprimulgus macrurus Horsfield, 1821, Java. Seven subspecies.
other common names
English: Horsfield's or long-tailed nightjar; French: Engoulevent de Horsfield; German: Langschwanz-Nachtschwalbe; Spanish: Chotacabras Macruro.
physical characteristics
10–13 in (25–33 cm); 1.9–2.7 oz (55–78 g). Grayish brown, blackish brown, buff, and white cryptic coloration. Sexually dimorphic.
distribution
Southern Asia from northeast Pakistan to Hainan, south through East Indies to northern and eastern Australia.
habitat
Open forests, woodland, scrub, and plantations.
behavior
Roosts during daytime, usually on ground. Active from dusk until before dawn. Territorial song a monotonous "t-chop" repeated in long series.
feeding ecology and diet
Hunts for insect prey using prolonged hawking flights and by shorter sallying flights from perches or ground.
reproductive biology
Unlined nest on ground with clutch of two eggs. Incubation at least mainly by female. Eggs are pale cream to dull buff with blackish brown spots. Incubation period is 21–22 days; fledging period is about three weeks. Small young have buff down.
conservation status
Not threatened.
significance to humans
Noticed mainly by nocturnal song, from which local names such as axe-, carpenter-, or hammer-bird are derived.
Fiery-necked nightjar
Caprimulgus pectoralis
subfamily
Caprimulginae
taxonomy
Caprimulgus pectoralis Cuvier, 1816, Western Cape, South Africa. Four subspecies.
other common names
English: Pectoral nightjar; French: Engoulevent musicien; German: Pfeifnachtschwalbe; Spanish: Chotacabras Músico.
physical characteristics
9–10 in (23–25 cm); 1.2–2.5 oz (35–70 g). Dark brown, grayish brown, brownish white, buff, tawny, and white cryptic coloration. Sexually dimorphic.
distribution
Africa from Kenya and Angola south to South Africa.
habitat
Woodlands and forest edges.
behavior
Roosts on ground during day; active mainly from dusk to dawn. Distinctive territorial song a whistled phrase rendered as Good Lord deliver us.
feeding ecology and diet
Catches insect prey on sallying flights from perches.
reproductive biology
Unlined nest on ground with clutch usually of two eggs. Eggs are white to pale pink, usually with brownish spots. Incubation by female during day, by male at night, period 18 days. Small
young have brownish down. Young able to fly when about 18 days old.
conservation status
Not threatened.
significance to humans
Usually not noticed by local people, except for its nocturnal songs.
Standard-winged nightjar
Macrodipteryx longipennis
subfamily
Caprimulginae
taxonomy
Caprimulgus longipennis Shaw, 1796, Sierra Leone. Monotypic.
other common names
French: Engoulevent à balanciers; German: Fahnennachtschwalbe; Spanish: Chotacabras Portaestandarte.
physical characteristics
8–9 in (20–23 cm), excluding long standards on wings of breeding male; 1.3–2.3 oz (37–65 g). Sexually dimorphic. Variable cryptic coloration; males often blacker with whiter speckles, while females are more buffy or sandy. Breeding males have unmistakable standards (extremely elongated second innermost primaries) on wings.
distribution
West and central Africa from the Gambia to southwest Sudan.
habitat
Lightly wooded or bushy savannas.
behavior
Roosts on ground during day; active from dusk until before dawn. Males assemble to display at leks that are visited by females.
feeding ecology and diet
Feeds on insects caught in sustained hawking flights.
reproductive biology
Unlike most members of the Caprimulgidae, probably polygynous. Unlined nest on ground with clutch of one or two eggs. Eggs are pale pink to buff-gray or brown, with dark spots of blotches. Incubation and care of young carried out by female alone. Small young have down that is buff, mottled with black on upperparts.
conservation status
Not threatened.
significance to humans
None known.
Resources
Books
Cleere, N. "Nightjars." In Handbook of the Birds of the World. Vol. 5, Barn-owls to Hummingbirds, edited by Josep del Hoyo, Andrew Elliott, and Jordi Sargatal. Barcelona: Lynx Edicions, 1999.
Holyoak, D.T. Nightjars and Their Allies. Oxford: Oxford University Press, 2001.
David T. Holyoak, PhD