Common Treecreeper
Encyclopedia
The Eurasian Treecreeper or Common Treecreeper (Certhia familiaris) is a small passerine
bird
also known in the British Isles
, where it is the only living member of its genus, simply as Treecreeper. It is similar to other treecreeper
s, and has a curved bill, patterned brown upperparts, whitish underparts, and long stiff tail feathers which help it creep up tree trunks. It can be most easily distinguished from the similar Short-toed Treecreeper
, which shares much of its Europe
an range, by its different song.
The Eurasian Treecreeper has nine or more subspecies which breed in different parts of its range in temperate Eurasia
. This species is found in woodlands of all kinds, but where it overlaps with the Short-toed Treecreeper in western Europe it is more likely to be found in coniferous forests or at higher altitudes. It nests in tree crevices or behind bark flakes, and favours introduced Giant Sequoia
as nest sites where they are available. The female typically lays five or six pink-speckled white eggs in the lined nest, but eggs and chicks are vulnerable to attack by woodpeckers and mammals, including squirrels.
The Eurasian Treecreeper is insectivorous
and climbs up tree trunks like a mouse, to search for insects which it picks from crevices in the bark with its fine curved bill. It then flies to the base of another tree with a distinctive erratic flight. This bird is solitary in winter, but may form communal roosts in cold weather.
The Eurasian Treecreeper is 12.5 cm (5 in) long and weighs 7.0–12.9 g
(0.25–0.46 oz
). It has warm brown upperparts intricately patterned with black, buff and white, and a plain brown tail. Its belly, flanks and vent area are tinged with buff. The sexes are similar, but the juvenile has duller upperparts than the adult, and its underparts are dull white with dark fine spotting on the flanks.
The contact call is a very quiet, thin and high-pitched sit, but the most distinctive call is a penetrating tsree, with a vibrato
quality, sometimes repeated as a series of notes. The male's song begins with srrih, srrih followed in turn by a few twittering notes, a longer descending ripple, and a whistle that falls and then rises.
The range of the Eurasian Treecreeper overlaps with that of several other treecreepers, which can present local identification problems. In Europe, the Eurasian Treecreeper shares much of its range with the Short-toed Treecreeper. Compared to that species, it is whiter below, warmer and more spotted above, and has a whiter supercilium
and slightly shorter bill. Visual identification, even in the hand, may be impossible for poorly marked birds. A singing treecreeper is usually identifiable, since Short-toed Treecreeper has a distinctive series of evenly spaced notes sounding quite different from the song of Eurasian Treecreeper; however, both species have been known to sing the other's song.
Three Himalayan subspecies of Eurasian Treecreeper are now sometimes given full species status as Hodgson's Treecreeper
, for example by BirdLife International
, but if they are retained as subspecies of Eurasian, they have to be distinguished from three other South Asian treecreepers. The plain tail of Eurasian Treecreeper differentiates it from Bar-tailed Treecreeper, which has a distinctive barred tail pattern, and its white throat is an obvious difference from Brown-throated Treecreeper. Rusty-flanked Treecreeper is more difficult to separate from Eurasian, but has more contrasting cinnamon, rather than buff, flanks.
The North American Brown Creeper
has never been recorded in Europe, but an autumn vagrant
would be difficult to identify, since it would not be singing, and the American species' call is much like that of Eurasian Treecreeper. In appearance, Brown Creeper is more like Short-toed than Eurasian, but a vagrant might still not be possible to identify with certainty given the similarities between the three species.
The Eurasian Treecreeper was first described under its current scientific name by Linnaeus
in his Systema naturae
in 1758. The binomial name is derived from Greek
kerthios, a small tree-dwelling bird described by Aristotle
and others, and Latin
familiaris, familiar or common.
This species is one of a group of very similar typical treecreeper
species, all placed in the single genus Certhia
. Eight species are currently recognised, in two evolution
ary lineages: a Holarctic
radiation, and a southern Asian group. The Holarctic group has a more warbling song, always (except in C. familiaris from China
) starting or ending with a shrill sreeh. Species in the southern group, in contrast, have a faster-paced trill without the sreeh sound. All the species have distinctive vocalizations and some subspecies have been elevated to species on the basis of their calls.
The Eurasian Treecreeper belongs to the northern group, along with the North America
n Brown Creeper, C. americana, the Short-toed Treecreeper, C. brachydactyla, of western Eurasia, and, if it is considered a separate species, Hodgson's Treecreeper, C. hodgsoni, from the southern rim of the Himalayas
.
The Brown Creeper has sometimes been considered to be a subspecies of Eurasian Treecreeper, but has closer affinities to Short-toed Treecreeper, and is normally now treated as a full species. Hodgson's Treecreeper is a more recent proposed split following studies of its cytochrome b
mtDNA sequence
and song structure that indicate that it may well be a distinct species from C. familiaris.
There are nine to twelve subspecies of Eurasian Treecreeper, depending on the taxonomic view taken, which are all very similar and often interbreed in areas where their ranges overlap. There is a general cline
in appearance from west to east across Eurasia, with subspecies becoming greyer above and whiter below, but this trend reverses east of the Amur River. The currently recognised subspecies are as follows:
to Japan
. It prefers mature trees, and in most of Europe, where it shares its range with Short-toed Treecreeper, it tends to be found mainly in coniferous forest, especially spruce
and fir
. However, where it is the only treecreeper, as in European Russia
, or the British Isles
, it frequents broadleaved or mixed woodland in preference to conifers.
The Eurasian Treecreeper breeds down to sea level in the north of its range, but tends to be a highland species further south. In the Pyrenees
it breeds above 1,370 metres (4,495 ft), in China from 400–2,100 metres (1,315–6,890 ft) and in southern Japan from 1,065–2,135 metres (3,495–7,000 ft). The breeding areas have July isotherms between 14–16 °C and 23–24 °C (57–61 °F and 72–73 °F).
The Eurasian Treecreeper is non-migratory
in the milder west and south of its breeding range, but some northern birds move south in winter, and individuals breeding on mountains may descend to a lower altitude in winter. Winter movements and post-breeding dispersal may lead to vagrancy outside the normal range. Wintering migrants of the Asian subspecies have been recorded in South Korea
and China, and the nominate form has been recorded west of its breeding range as far as Orkney, Scotland
. The Eurasian Treecreeper has also occurred as a vagrant to the Channel Islands
(where the Short-toed is the resident species), Majorca and the Faroe Islands
.
(declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.
It is common through much of its range, but in the northernmost areas it is rare, since it is vulnerable to hard winters, especially if its feeding is disrupted by an ice glaze on the trees or freezing rain. It is also uncommon in Turkey and the Caucasus
. In the west of its range it has spread to the Outer Hebrides
in Scotland, pushed further north in Norway
, and first bred in the Netherlands
in 1993.
The Eurasian Treecreeper breeds from the age of one year, nesting in tree crevices or behind bark flakes. Where present, the introduced North American Giant Sequoia
is a favourite nesting tree, since a nest cavity can be easily hollowed out in its soft bark. Crevices in buildings or walls are sometimes used, and artificial nest boxes or flaps may be preferred in coniferous woodland. The nest has a base of twigs, pine needles, grass or bark, and a lining of finer material such as feathers, wool, moss, lichen
or spider web.
In Europe, the typical clutch of five–six eggs is laid between March and June, but in Japan three–five eggs are laid from May to July. The eggs are white with very fine pinkish speckles mainly at the broad end, measure 16 x 12 mm (0.5 x 0.6 in) and weigh 1.2 g (0.04 oz) of which 6% is shell. The eggs are incubated by the female alone for 13–17 days until the altricial
downy chicks hatch; they are then fed by both parents, but brooded by the female alone, for a further 15–17 days to fledging. Juveniles return to the nest for a few nights after fledging. About 20% of pairs, mainly in the south and west, raise a second brood.
Predators of treecreeper nests and young include the Great Spotted Woodpecker
, Red Squirrel
, and small mustelids
, and predation is about three times higher in fragmented landscapes than in solid blocks of woodland (32.4% against 12.0% in less fragmented woodlands). The predation rate increases with the amount of forest edge close to a nest site, and also the presence of nearby agricultural land, in both cases probably because of a higher degree of mustelid predation. This species is parasitised in the nest by the moorhen flea
, Dasypsyllus gallinulae. The juvenile survival rate of this species is unknown, but 47.7% of adults survive each year. The typical lifespan is two years, but the maximum recorded age is eight years and ten months.
The Eurasian Treecreeper typically seeks invertebrate
food on tree trunks, starting near the tree base and working its way up using its stiff tail feathers for support. Unlike a nuthatch
, it does not come down trees head first, but flies to the base of another nearby tree. It uses its long thin bill to extract insect
s and spider
s from crevices in the bark. Although normally found on trees, it will occasionally hunt prey items on walls, bare ground, or amongst fallen pine needles, and may add some conifer seeds to its diet in the colder months.
The female Eurasian Treecreeper forages primarily on the upper parts of the tree trunks, while the male uses the lower parts. A study in Finland
found that if a male disappears, the unpaired female will forage at lower heights, spend less time on each tree and have shorter foraging bouts than a paired female.
This bird may sometimes join mixed-species feeding flock
s in winter, but it does not appear to share the resources found by accompanying tits and Goldcrest
s, and may just be benefiting from the extra vigilance of a flock. Wood ants
share the same habitat as the treecreeper, and also feed on invertebrates on tree trunks. The Finnish researchers found that where the ants have been foraging, there are fewer arthropod
s, and male treecreepers spent a shorter time on spruce trunks visited by ants.
plumage and a quiet call, the Eurasian Treecreeper is easily overlooked as it hops mouse-like
up a vertical trunk, progressing in short hops, using its stiff tail and widely splayed feet as support. Nevertheless, it is not wary, and is largely indifferent to the presence of humans. It has a distinctive erratic and undulating flight, alternating fluttering butterfly-like
wing beats with side-slips and tumbles. Migrating birds may fly by day or night, but the extent of movements is usually masked by resident populations. It is solitary in winter, but in cold weather up to a dozen or more birds will roost together in a suitable sheltered crevice.
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
also known in the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...
, where it is the only living member of its genus, simply as Treecreeper. It is similar to other treecreeper
Certhia
Certhia is the genus of birds containing the typical treecreepers, which together with the Spotted Creeper make up the family Certhiidae.The typical treecreepers occur in many wooded parts of the North Temperate Zone...
s, and has a curved bill, patterned brown upperparts, whitish underparts, and long stiff tail feathers which help it creep up tree trunks. It can be most easily distinguished from the similar Short-toed Treecreeper
Short-toed Treecreeper
The Short-toed Treecreeper, Certhia brachydactyla, is a small passerine bird found in woodlands through much of the warmer regions of Europe and into north Africa. It has a generally more southerly distribution than the other European treecreeper species, the Common Treecreeper, with which it is...
, which shares much of its Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an range, by its different song.
The Eurasian Treecreeper has nine or more subspecies which breed in different parts of its range in temperate Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
. This species is found in woodlands of all kinds, but where it overlaps with the Short-toed Treecreeper in western Europe it is more likely to be found in coniferous forests or at higher altitudes. It nests in tree crevices or behind bark flakes, and favours introduced Giant Sequoia
Sequoiadendron
Sequoiadendron giganteum is the sole living species in the genus Sequoiadendron, and one of three species of coniferous trees known as redwoods, classified in the family Cupressaceae in the subfamily Sequoioideae, together with Sequoia sempervirens and...
as nest sites where they are available. The female typically lays five or six pink-speckled white eggs in the lined nest, but eggs and chicks are vulnerable to attack by woodpeckers and mammals, including squirrels.
The Eurasian Treecreeper is insectivorous
Insectivore
An insectivore is a type of carnivore with a diet that consists chiefly of insects and similar small creatures. An alternate term is entomophage, which also refers to the human practice of eating insects....
and climbs up tree trunks like a mouse, to search for insects which it picks from crevices in the bark with its fine curved bill. It then flies to the base of another tree with a distinctive erratic flight. This bird is solitary in winter, but may form communal roosts in cold weather.
Description
Similar in appearance, all treecreepers are small birds with streaked and spotted brown upperparts, rufous rumps and whitish underparts. They have long decurved bills, and long rigid tail feathers that provide support as they creep up tree trunks looking for insects.The Eurasian Treecreeper is 12.5 cm (5 in) long and weighs 7.0–12.9 g
Gram
The gram is a metric system unit of mass....
(0.25–0.46 oz
Ounce
The ounce is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of different systems, including various systems of mass that form part of the imperial and United States customary systems...
). It has warm brown upperparts intricately patterned with black, buff and white, and a plain brown tail. Its belly, flanks and vent area are tinged with buff. The sexes are similar, but the juvenile has duller upperparts than the adult, and its underparts are dull white with dark fine spotting on the flanks.
The contact call is a very quiet, thin and high-pitched sit, but the most distinctive call is a penetrating tsree, with a vibrato
Vibrato
Vibrato is a musical effect consisting of a regular, pulsating change of pitch. It is used to add expression to vocal and instrumental music. Vibrato is typically characterised in terms of two factors: the amount of pitch variation and the speed with which the pitch is varied .-Vibrato and...
quality, sometimes repeated as a series of notes. The male's song begins with srrih, srrih followed in turn by a few twittering notes, a longer descending ripple, and a whistle that falls and then rises.
The range of the Eurasian Treecreeper overlaps with that of several other treecreepers, which can present local identification problems. In Europe, the Eurasian Treecreeper shares much of its range with the Short-toed Treecreeper. Compared to that species, it is whiter below, warmer and more spotted above, and has a whiter supercilium
Supercilium
The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head. Also known as an "eyebrow", it is distinct from the eyestripe, which is a line which runs...
and slightly shorter bill. Visual identification, even in the hand, may be impossible for poorly marked birds. A singing treecreeper is usually identifiable, since Short-toed Treecreeper has a distinctive series of evenly spaced notes sounding quite different from the song of Eurasian Treecreeper; however, both species have been known to sing the other's song.
Three Himalayan subspecies of Eurasian Treecreeper are now sometimes given full species status as Hodgson's Treecreeper
Hodgson's Treecreeper
Hodgson's Treecreeper, Certhia hodgsoni, is a small passerine bird from the southern rim of the Himalayas. Its specific distinctness from the Common Treecreeper was recently validated.-Description:...
, for example by BirdLife International
BirdLife International
BirdLife International is a global Partnership of conservation organisations that strives to conserve birds, their habitats and global biodiversity, working with people towards sustainability in the use of natural resources...
, but if they are retained as subspecies of Eurasian, they have to be distinguished from three other South Asian treecreepers. The plain tail of Eurasian Treecreeper differentiates it from Bar-tailed Treecreeper, which has a distinctive barred tail pattern, and its white throat is an obvious difference from Brown-throated Treecreeper. Rusty-flanked Treecreeper is more difficult to separate from Eurasian, but has more contrasting cinnamon, rather than buff, flanks.
The North American Brown Creeper
Brown Creeper
-Description:Adults are brown on the upperparts with light spotting, resembling a piece of tree bark, with white underparts. They have a long thin bill with a slight downward curve and a long tail. The male creeper has a slightly larger bill than the female...
has never been recorded in Europe, but an autumn vagrant
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...
would be difficult to identify, since it would not be singing, and the American species' call is much like that of Eurasian Treecreeper. In appearance, Brown Creeper is more like Short-toed than Eurasian, but a vagrant might still not be possible to identify with certainty given the similarities between the three species.
Taxonomy
Carolus Linnaeus
Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
in his Systema naturae
Systema Naturae
The book was one of the major works of the Swedish botanist, zoologist and physician Carolus Linnaeus. The first edition was published in 1735...
in 1758. The binomial name is derived from Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
kerthios, a small tree-dwelling bird described by Aristotle
Aristotle
Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...
and others, and Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
familiaris, familiar or common.
This species is one of a group of very similar typical treecreeper
Certhia
Certhia is the genus of birds containing the typical treecreepers, which together with the Spotted Creeper make up the family Certhiidae.The typical treecreepers occur in many wooded parts of the North Temperate Zone...
species, all placed in the single genus Certhia
Certhia
Certhia is the genus of birds containing the typical treecreepers, which together with the Spotted Creeper make up the family Certhiidae.The typical treecreepers occur in many wooded parts of the North Temperate Zone...
. Eight species are currently recognised, in two evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
ary lineages: a Holarctic
Holarctic
The Holarctic ecozone refers to the habitats found throughout the northern continents of the world as a whole. This region is divided into the Palearctic, consisting of Northern Africa and all of Eurasia, with the exception of Southeast Asia and the Indian subcontinent, and the Nearctic,...
radiation, and a southern Asian group. The Holarctic group has a more warbling song, always (except in C. familiaris from China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
) starting or ending with a shrill sreeh. Species in the southern group, in contrast, have a faster-paced trill without the sreeh sound. All the species have distinctive vocalizations and some subspecies have been elevated to species on the basis of their calls.
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n Brown Creeper, C. americana, the Short-toed Treecreeper, C. brachydactyla, of western Eurasia, and, if it is considered a separate species, Hodgson's Treecreeper, C. hodgsoni, from the southern rim of the Himalayas
Himalayas
The Himalaya Range or Himalaya Mountains Sanskrit: Devanagari: हिमालय, literally "abode of snow"), usually called the Himalayas or Himalaya for short, is a mountain range in Asia, separating the Indian subcontinent from the Tibetan Plateau...
.
The Brown Creeper has sometimes been considered to be a subspecies of Eurasian Treecreeper, but has closer affinities to Short-toed Treecreeper, and is normally now treated as a full species. Hodgson's Treecreeper is a more recent proposed split following studies of its cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
mtDNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
and song structure that indicate that it may well be a distinct species from C. familiaris.
There are nine to twelve subspecies of Eurasian Treecreeper, depending on the taxonomic view taken, which are all very similar and often interbreed in areas where their ranges overlap. There is a general cline
Cline (population genetics)
In biology, an ecocline or simply cline describes an ecotone in which a series of biocommunities display continuous gradient...
in appearance from west to east across Eurasia, with subspecies becoming greyer above and whiter below, but this trend reverses east of the Amur River. The currently recognised subspecies are as follows:
| Subspecies | Range | Notes |
|---|---|---|
| C. f. britannica | Great Britain Great Britain Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles... and Ireland Ireland Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth... |
Irish treecreepers, slightly darker than British ones, have sometimes been given subspecific status |
| C. f. macrodactyla | Western Europe Europe Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting... |
Paler above and whiter below than C. f. britannica |
| C. f. corsa | Corsica Corsica Corsica is an island in the Mediterranean Sea. It is located west of Italy, southeast of the French mainland, and north of the island of Sardinia.... |
Buff-tinged underparts and more contrasted upperparts than C. f. macrodactyla |
| C. f. familiaris | Scandinavia Scandinavia Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,... and eastern Europe east to western Siberia Siberia Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th... |
Nominate subspecies. Paler above than C. f. macrodactyla, white underparts |
| C. f. daurica | Eastern Siberia, northern Mongolia Mongolia Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest... |
Paler and greyer than the nominate subspecies |
| C. f. orientalis | Amur basin, northeast China and Korea Korea Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the... |
Similar to nominate, but with stronger streaking above |
| C. f. japonica | Japan Japan Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south... |
Darker and more rufous than C. f. duarica |
| C. f. persica | The Crimea Crimea Crimea , or the Autonomous Republic of Crimea , is a sub-national unit, an autonomous republic, of Ukraine. It is located on the northern coast of the Black Sea, occupying a peninsula of the same name... and Turkey Turkey Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe... east to northern Iran Iran Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia... |
Duller and less rufous than the nominate form |
| C. f. tianchanica | Northwestern China and adjacent regions of the former USSR | Paler and more rufous than nominate subspecies |
| C. f. hodgsoni | Western Himalayas of, Kashmir Kashmir Kashmir is the northwestern region of the Indian subcontinent. Until the mid-19th century, the term Kashmir geographically denoted only the valley between the Great Himalayas and the Pir Panjal mountain range... |
Often treated as a full species, Hodgson's Treecreeper, C. hodgsonii. |
| C. f. mandellii | Eastern Himalayas of India, Nepal Nepal Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India... |
Often now treated as a subspecies of Hodgson's Treecreeper |
| C. f. khamensis | China, Sichuan Sichuan ' , known formerly in the West by its postal map spellings of Szechwan or Szechuan is a province in Southwest China with its capital in Chengdu... |
Often now treated as a subspecies of Hodgson's Treecreeper |
Distribution and habitat
The Eurasian Treecreeper is the most widespread member of its genus, breeding in temperate woodlands across Eurasia from IrelandIreland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
to Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
. It prefers mature trees, and in most of Europe, where it shares its range with Short-toed Treecreeper, it tends to be found mainly in coniferous forest, especially spruce
Spruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...
and fir
Fir
Firs are a genus of 48–55 species of evergreen conifers in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range...
. However, where it is the only treecreeper, as in European Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, or the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...
, it frequents broadleaved or mixed woodland in preference to conifers.
The Eurasian Treecreeper breeds down to sea level in the north of its range, but tends to be a highland species further south. In the Pyrenees
Pyrenees
The Pyrenees is a range of mountains in southwest Europe that forms a natural border between France and Spain...
it breeds above 1,370 metres (4,495 ft), in China from 400–2,100 metres (1,315–6,890 ft) and in southern Japan from 1,065–2,135 metres (3,495–7,000 ft). The breeding areas have July isotherms between 14–16 °C and 23–24 °C (57–61 °F and 72–73 °F).
The Eurasian Treecreeper is non-migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
in the milder west and south of its breeding range, but some northern birds move south in winter, and individuals breeding on mountains may descend to a lower altitude in winter. Winter movements and post-breeding dispersal may lead to vagrancy outside the normal range. Wintering migrants of the Asian subspecies have been recorded in South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...
and China, and the nominate form has been recorded west of its breeding range as far as Orkney, Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
. The Eurasian Treecreeper has also occurred as a vagrant to the Channel Islands
Channel Islands
The Channel Islands are an archipelago of British Crown Dependencies in the English Channel, off the French coast of Normandy. They include two separate bailiwicks: the Bailiwick of Guernsey and the Bailiwick of Jersey...
(where the Short-toed is the resident species), Majorca and the Faroe Islands
Faroe Islands
The Faroe Islands are an island group situated between the Norwegian Sea and the North Atlantic Ocean, approximately halfway between Scotland and Iceland. The Faroe Islands are a self-governing territory within the Kingdom of Denmark, along with Denmark proper and Greenland...
.
Status
This species has an extensive range of about 10 million km2 (3.8 million square miles). It has a large population, including an estimated 11–20 million individuals in Europe alone. Population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red ListIUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
(declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.
It is common through much of its range, but in the northernmost areas it is rare, since it is vulnerable to hard winters, especially if its feeding is disrupted by an ice glaze on the trees or freezing rain. It is also uncommon in Turkey and the Caucasus
Caucasus
The Caucasus, also Caucas or Caucasia , is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea...
. In the west of its range it has spread to the Outer Hebrides
Outer Hebrides
The Outer Hebrides also known as the Western Isles and the Long Island, is an island chain off the west coast of Scotland. The islands are geographically contiguous with Comhairle nan Eilean Siar, one of the 32 unitary council areas of Scotland...
in Scotland, pushed further north in Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
, and first bred in the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
in 1993.
Breeding
Sequoiadendron
Sequoiadendron giganteum is the sole living species in the genus Sequoiadendron, and one of three species of coniferous trees known as redwoods, classified in the family Cupressaceae in the subfamily Sequoioideae, together with Sequoia sempervirens and...
is a favourite nesting tree, since a nest cavity can be easily hollowed out in its soft bark. Crevices in buildings or walls are sometimes used, and artificial nest boxes or flaps may be preferred in coniferous woodland. The nest has a base of twigs, pine needles, grass or bark, and a lining of finer material such as feathers, wool, moss, lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...
or spider web.
In Europe, the typical clutch of five–six eggs is laid between March and June, but in Japan three–five eggs are laid from May to July. The eggs are white with very fine pinkish speckles mainly at the broad end, measure 16 x 12 mm (0.5 x 0.6 in) and weigh 1.2 g (0.04 oz) of which 6% is shell. The eggs are incubated by the female alone for 13–17 days until the altricial
Altricial
Altricial, meaning "requiring nourishment", refers to a pattern of growth and development in organisms which are incapable of moving around on their own soon after hatching or being born...
downy chicks hatch; they are then fed by both parents, but brooded by the female alone, for a further 15–17 days to fledging. Juveniles return to the nest for a few nights after fledging. About 20% of pairs, mainly in the south and west, raise a second brood.
Predators of treecreeper nests and young include the Great Spotted Woodpecker
Great Spotted Woodpecker
The Great Spotted Woodpecker , Dendrocopos major, is a bird species of the woodpecker family . It is distributed throughout Europe and northern Asia, and usually resident year-round except in the colder parts of its range...
, Red Squirrel
Red Squirrel
The red squirrel or Eurasian red squirrel is a species of tree squirrel in the genus Sciurus common throughout Eurasia...
, and small mustelids
Mustelidae
Mustelidae , commonly referred to as the weasel family, are a family of carnivorous mammals. Mustelids are diverse and the largest family in the order Carnivora, at least partly because in the past it has been a catch-all category for many early or poorly differentiated taxa...
, and predation is about three times higher in fragmented landscapes than in solid blocks of woodland (32.4% against 12.0% in less fragmented woodlands). The predation rate increases with the amount of forest edge close to a nest site, and also the presence of nearby agricultural land, in both cases probably because of a higher degree of mustelid predation. This species is parasitised in the nest by the moorhen flea
Moorhen flea
The moorhen flea, Dasypsyllus gallinulae, originally from South America, is now a globally widespread flea species. It is a large flea, easily identified because the male has two heavy horn-like spines on one of the genital flaps, and the female has a deep "bite" on the seventh sternite.It is found...
, Dasypsyllus gallinulae. The juvenile survival rate of this species is unknown, but 47.7% of adults survive each year. The typical lifespan is two years, but the maximum recorded age is eight years and ten months.
Feeding
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
food on tree trunks, starting near the tree base and working its way up using its stiff tail feathers for support. Unlike a nuthatch
Nuthatch
The nuthatches are a genus, Sitta, of small passerine birds belonging to the family Sittidae. Characterised by large heads, short tails, and powerful bills and feet, nuthatches advertise their territory using loud, simple songs...
, it does not come down trees head first, but flies to the base of another nearby tree. It uses its long thin bill to extract insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s and spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
s from crevices in the bark. Although normally found on trees, it will occasionally hunt prey items on walls, bare ground, or amongst fallen pine needles, and may add some conifer seeds to its diet in the colder months.
The female Eurasian Treecreeper forages primarily on the upper parts of the tree trunks, while the male uses the lower parts. A study in Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
found that if a male disappears, the unpaired female will forage at lower heights, spend less time on each tree and have shorter foraging bouts than a paired female.
This bird may sometimes join mixed-species feeding flock
Mixed-species feeding flock
A mixed-species feeding flock, also termed a mixed-species foraging flock, mixed hunting party or informally bird wave, is a flock of usually insectivorous birds of different species, that join each other and move together while foraging...
s in winter, but it does not appear to share the resources found by accompanying tits and Goldcrest
Goldcrest
The Goldcrest, Regulus regulus, is a very small passerine bird in the kinglet family. Its colourful golden crest feathers gives rise to its English and scientific names, and possibly to it being called the "king of the birds" in European folklore. Several subspecies are recognised across the very...
s, and may just be benefiting from the extra vigilance of a flock. Wood ants
Formica rufa group
The Formica rufa group is a sub-generic group within the genus Formica, first proposed by William Morton Wheeler. It contains the large, mound-building species of Formica commonly termed "wood ants"....
share the same habitat as the treecreeper, and also feed on invertebrates on tree trunks. The Finnish researchers found that where the ants have been foraging, there are fewer arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s, and male treecreepers spent a shorter time on spruce trunks visited by ants.
Habits
As a small woodland bird with crypticCrypsis
In ecology, crypsis is the ability of an organism to avoid observation or detection by other organisms. It may be either a predation strategy or an antipredator adaptation, and methods include camouflage, nocturnality, subterranean lifestyle, transparency, and mimicry...
plumage and a quiet call, the Eurasian Treecreeper is easily overlooked as it hops mouse-like
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...
up a vertical trunk, progressing in short hops, using its stiff tail and widely splayed feet as support. Nevertheless, it is not wary, and is largely indifferent to the presence of humans. It has a distinctive erratic and undulating flight, alternating fluttering butterfly-like
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
wing beats with side-slips and tumbles. Migrating birds may fly by day or night, but the extent of movements is usually masked by resident populations. It is solitary in winter, but in cold weather up to a dozen or more birds will roost together in a suitable sheltered crevice.
External links
- Eurasian Treecreeper videos, photos & sounds on the Internet Bird Collection.
- Article on the identification of Common and Short-toed Treecreepers (in German with an English summary)
- Information and Illustration on European Tree Creeper from A Field Guide to Birds of Armenia