Common nightingale

Name and taxonomy

The English name joins night with the Old English verb galan, which meant to sing. The form nihtegale is more than a thousand years old and means night singer. The genus name Luscinia is simply the Latin for a nightingale. The species name megarhynchos comes from Greek words for great and bill. Early writers thought the singer was the female, and the belief lasted for centuries.

Three subspecies are recognised, and each has its own breeding range. The western form breeds from western Europe through North Africa to Asia Minor. The Caucasian form runs from the Caucasus and eastern Turkey into Iran and Iraq. The eastern form breeds from the Aral Sea across to Mongolia. All three leave for Africa in autumn, but each winters in a different part of it.

Evolution and relatives

The nightingale sits in the Muscicapidae, the Old World flycatchers. It belongs to the ground-loving group within that family that birders call the chats. Ornithologists once filed the chats with the thrushes because they look like small thrushes. Genetic work moved them, and the thrush-like build turned out to be convergent evolution.

The closest relative is the thrush nightingale, which breeds further north and east. The two ranges overlap in places, and the birds sometimes hybridise there. The common nightingale prefers a milder and warmer climate than its northern cousin. The European robin is another member of the same group, and it is slightly smaller. Like other chats, the nightingale probably spread from a ground-feeding ancestor of open woodland.

Appearance

This appears to be a plain bird by any measure. The upper parts are an even brown, and the underside fades to buff and then to white. The tail is broad and a warm chestnut, and it is the one splash of colour. The eye is large and black, ringed by a pale circle of feathers. A bird measures 14 to 17 cm, so it is a shade larger than a European robin.

Males and females look the same in the field. Males average a little longer with a wider wing, and the span runs from 20 to 24 cm. Females sometimes weigh more, because a singing male burns energy at a higher rate. Adults weigh 18 to 23 g, and about 21 g is normal. The eastern and Caucasian forms are paler above and show a clearer stripe over the eye.

Habitat and range

The nightingale needs thick low cover with bare ground beneath it. Coppiced woodland suits it well, and hazel is the tree most often named. The cover hides the bird from predators while it hunts on the open floor below. A closed canopy is no good, probably because the shade kills the shrub layer. The nest sits on the ground or just above it in dense growth.

German research listed the conditions that mark out good breeding ground. The sites lie below 400 metres, with growing season temperatures above 14 degrees Celsius. They have more than 20 warm days a year above 25 degrees and dry summers. Annual rainfall stays under 750 millimetres.

The breeding range covers central and southern Europe, North Africa and central Asia. France, Italy and Spain hold the birds most visitors hear. Britain lies at the northern edge, and the range there has pulled back. Winter takes the whole population to tropical Africa, from the western Sahara to Kenya and Nigeria. The species has never established itself in the Americas.

Diet and feeding

The nightingale is an insect eater first and last. Beetles, ants, spiders and worms taken from the ground make up most meals. Insect larvae are a large part of what the parents carry to the nest. In autumn the bird adds berries and other soft fruit before it migrates.

Feeding happens on the woodland floor under cover. The bird likely hops, pauses and picks prey from leaf litter and bare soil. Bare ground under a thicket appears to matter as much as the thicket itself. A male that sings through the night must spend the day feeding to make the weight back. That trade takes time away from song and raises the risk of being seen by a predator.

Behaviour and social life

Outside the breeding season the nightingale lives alone. There is no flock and no pecking order in this species. Birds stay in dense shrubs and thickets and keep away from open ground. A bird that senses danger often freezes rather than flying, which makes it very hard to see. Most people who meet a nightingale only ever hear one.

Males hold territories and defend them hard. A rival that crosses the line is chased and fought. Song contests between neighbouring males probably settle much of the argument without a fight. Away from migration the birds fly only short hops from branch to branch. The same birds then cross the Sahara twice a year, which seems a striking contrast.

Communication and senses

The song is loud and mixes whistles, trills and gurgling notes. A rising whistled crescendo is the mark of this species and the thrush nightingale lacks it. Males average about 190 different song types, and some reach 250. Exceptional birds pass 300 song types, and older males hold larger sets than young ones. One study counted about 1,160 syllables in the species, against 108 for the blackbird.

Researchers split the output into whistle songs and non-whistle songs. Whistle songs carry furthest and do the work of attracting a mate and holding a territory. A male drops his whistle songs once he has paired. Night song belongs to unpaired males and probably serves to draw a female in. Dawn song in the hour before sunrise is thought to defend the territory instead.

A night session can run for seven or eight hours with few breaks. Birds in towns sing louder than birds in the country to beat the background noise. Males cut their night singing when owls are about, which lowers the risk. The alarm call is a low croak that sounds more like a frog than a bird.

Reproduction and life cycle

Nightingales pair for one season at a time. In general, males arrive first, and each takes a territory and sings to advertise it. Female choice appears to run on song, and the best singers pair soonest. Older males with larger song sets do better than young males. As many as 49 percent of males may fail to find a mate in a season.

Breeding starts in the middle of May in most of the range. The female builds the nest in a dense shrub from dried leaves, grass and twigs. A clutch holds about four or five eggs. Each egg measures about 21 by 16 millimetres and weighs about 2.7 g. The female alone incubates, and the eggs hatch after 13 or 14 days.

Both parents guard the nest and feed the chicks once they hatch. The young leave the nest 11 to 13 days after hatching. Birds can breed at one year old. A typical nightingale lives 1 to 5 years in the wild. The oldest known bird reached 8.3 years, or 8 years and 4 months.

Predators and threats

The tawny owl is the main predator of adult nightingales. The owl hunts the same woods at the same hours, so night song probably carries a cost. Ground nests are open to whatever walks past, so eggs and chicks appear to be the weakest point. The bird hosts a gut parasite named Apororhynchus silesiacus.

Habitat change is the larger threat. Coppicing has stopped in many woods, and the shrub layer probably closes over or thins out. Deer are a direct cause in Britain, where muntjac and roe deer graze out the low cover. Climate is a second factor, and the species does badly where summers turn cool and wet. Conditions in the African wintering grounds may be changing as well.

Population and conservation

The IUCN lists the common nightingale as Least Concern. Europe holds an estimated 3.2 to 7 million breeding pairs. That total appears to keep the global status green even where local declines are steep. Naturalists have logged 17931 observations of the species on iNaturalist. GBIF holds records from 115 countries and territories.

The European trend seems poor. One report put the European decline at 63 percent between 1980 and 2005. British numbers fell by 53 percent between 1995 and 2008. A British Trust for Ornithology survey in 2012 and 2013 found about 3,300 territories. Almost all of them lay in Kent, Essex, Suffolk and the two Sussex counties.

The RSPB now puts the British figure at around 6,700 singing males. The bird sits on the British red list of conservation concern. Israel lists it as Near Threatened, while Portugal and Switzerland list it as Least Concern. Conservation work in Britain appears to aim at cutting coppice again and fencing deer out.

Relationship with humans

People have probably listened to nightingales for as long as they have written poems. The bird does no harm to crops, buildings or people. Animal Diversity Web records no negative effect of the species on human interests. Birdwatchers travel to a handful of reserves each May to hear the song.

Recordings of the song appear to have carried it far beyond its range. A famous wartime recording caught a nightingale singing while bombers flew over a garden. Manfred Mann's Earth Band used that recording and named an album after it in 1975. The single Let Nature Sing put the song into the British charts in 2019. Caged nightingales were once a trade, and the bird probably has no future as a pet.

In culture and myth

Greek myth turned a woman into a nightingale. Tereus, king of Thrace, attacked Philomela and cut out her tongue to keep her quiet. Philomela worked the story into a woven cloth and had it carried to her sister Procne, his wife. Procne killed their son and served him to Tereus, and the gods then turned the sisters into birds. Roman writers made Philomela the nightingale, and readers heard the song as a lament ever after.

European poets took the bird as the image of the poet. Aristophanes, Virgil, Chaucer and Shakespeare all put the nightingale to that use. Coleridge argued against the sad reading in a poem printed in 1798. John Keats wrote his Ode to a Nightingale in 1819, and it became the best known of them all. Shelley called the poet a nightingale who sits in the dark and sings to itself.

Iran names the nightingale its national bird. Persian verse pairs the bird with the rose, and the bird loves what it cannot have. Urdu and Turkish poetry carry the same pairing under the name bulbul. Ukrainian poetry uses the bird for longing, and one legend brings it from India to cheer sad singers. The Baha'i Faith uses the nightingale as a figure for the writings of Baha'u'llah.