Ptyonoprogne
Encyclopedia
The crag martins are three species of small passerine
birds in the genus
Ptyonoprogne of the swallow
family. They are the Eurasian Crag Martin (P. rupestris), the Rock Martin (P. fuligula) and the Dusky Crag Martin
(P. concolor). They are closely related to each other, and have formerly sometimes been considered to be one species. They are closely related to the Hirundo
barn swallows and are placed in that genus by some authorities. These are small swallows with brown upperparts, paler underparts without a breast band, and a square tail with white patches. They can be distinguished from each other on size, the colour shade of the upperparts and underparts, and minor plumage details like throat colour. They resemble the Sand Martin
, but are darker below, and lack a breast band.
These are species of craggy mountainous habitat
s, although all three will also frequent human habitation. The African Rock Martin and the south Asian Dusky Crag Martin are resident, but the Eurasian Crag Martin is a partial migrant
; birds breeding in southern Europe are largely resident, but some northern breeders and most Asian birds are migratory, wintering in north Africa or India
. They do not normally form large breeding colonies, but are more gregarious outside the breeding season. These martins build neat mud nests
under cliff
overhangs or in crevices in their mountain homes, and have readily adapted to the artificial cliffs provided by buildings and motorway bridges. Up to five eggs
, white with dark blotches at the wider end, may be laid, and a second clutch is common. Ptyonoprogne martins feed mainly on insect
s caught in flight, and patrol cliffs near the breeding site with a slow hunting flight as they seek their prey. They may be hunted by falcon
s and infected with mite
s and flea
s, but their large ranges and populations mean that none of the crag martins are considered to be threatened, and all are classed as Least Concern
on the IUCN Red List
.
in 1769, the Rock Martin (P. fuligula), described by German zoologist Martin Lichtenstein
in 1842, and the Dusky Crag Martin
(P. concolor) formally described in 1832 as Hirundo concolor by British soldier and ornithologist William Henry Sykes
. They were moved to the new genus Ptyonoprogne by German ornithologist Heinrich Gustav Reichenbach
in 1850. The genus name is derived from the Greek ptuon (φτυον), "a fan", referring to the shape of the opened tail, and Procne (Πρόκνη), a mythological girl who was turned into a swallow.
These are members of the swallow family of birds, and are placed in the Hirundininae subfamily which comprises all swallows and martins except the very distinctive river martin
s. DNA sequence
studies suggest that there are three major groupings within the Hirundininae, broadly correlating with the type of nest built. The groups are the "core martins" including burrowing species like the Sand Martin
, the "nest-adopters", which are birds like the Tree Swallow
that utilise natural cavities, and the "mud nest builders". Ptyonoprogne species construct a mud nest and therefore belong to the latter group; They resemble the Hirundo
species in that they make open cup nests, whereas Delichon
martins build closed cups, and the Cecropis
and Petrochelidon
swallows, have retort-like
closed nests with an entrance tunnel. The genus Ptyonoprogne is closely related to the larger swallow genus Hirundo into which it is often subsumed, but a DNA analysis showed that a coherent enlarged Hirundo genus should contain all the mud-builder genera. Although the nests of the Ptyonoprogne crag martins resembles those of typical Hirundo species like the Barn Swallow
, the DNA research showed that if the Delichon
house martins are considered to be a separate genus, as is normally the case, Cecropis
, Petrochelidon
and Ptyonoprogne should also be split off.
These three species have formerly been considered conspecific; conversely, the small, pale northern subspecies of Rock Martin found in the mountains of North Africa
and the Arabia
n peninsular are sometimes split as the Pale Crag Martin, Ptyonoprogne obsoleta.
These drab martins can only be confused with each other, or with sand martins of the genus Riparia. Even the smaller Ptyonoprogne species are slightly larger and more robust than the Sand Martin
and Brown-throated Sand Martin
, and have the white tail spots which are absent from the Riparia martins. Where the ranges of Ptyonoprogne species overlap, the Eurasian Crag Martin is darker, browner and 15% larger than the Rock Martin, and larger and paler, particularly on its underparts, than the Dusky Crag Martin. The white tail spots of the Eurasian Crag Martin are significantly larger than those of both its relatives. In the east of its range, the Rock Martin always has lighter, more contrasted underparts than the Dusky Crag Martin.
. The Eurasian Crag Martin breeds from Iberia
and northwesternmost Africa through southern Europe, the Persian Gulf
and the Himalayas
to southwestern and northeastern China. Northern populations of the Eurasian Crag Martin are migratory
, with European birds wintering in north Africa, Senegal, Ethiopia and the Nile Valley
, and Asian breeders going to southern China, the Indian subcontinent and the Middle East
. Some European birds stay north of the Mediterranean, and, like populations in warmer areas such as India, Turkey and Cyprus, just move to lower ground after breeding. The Dusky Crag Martin and Rock are largely resident apart from local movements after breeding, when many birds descend to lower altitudes, although some pale northern Rock Martins from North African and southern Arabian may winter further south alongside the local subspecies in Ethiopia, Mali and Mauritania.
The crag martins mainly breed on dry, warm and sheltered cliffs in mountainous areas with crags and gorges, and the Eurasian Crag Martin reaches 5,000 m (16,500 ft) in Central Asia. The use of buildings as artificial cliffs has enabled breeding expansion into lowland areas, particularly for the two tropical species, and the Rock Martin breeds in desert towns. In South Asia, migrant Eurasian birds sometimes join with flocks of the Dusky Crag Martin and roost communally on ledges of cliffs or buildings in winter.
Martin pairs often nest alone, although where suitable sites are available small loose colonies
may form. These are more common south of the Sahara, where up to 40 Rock Martin pairs together have been recoded. Crag martins aggressively defend their nesting territory against conspecifics and other species. The nest, built by both adults over several weeks, is made from several hundred mud pellets and lined with soft dry grass or sometimes feathers. It may be a half-cup when constructed under an overhang on a vertical wall or cliff, or shaped as a bowl like that of the Barn Swallow when placed on a sheltered ledge. The nest may be built on a rock cliff face, in a crevice or on a man-made structure, and is re-used for the second brood and in subsequent years. Usually two broods are raised, and the Rock Martin may nest for a third time in a season.
The clutch is two to five eggs that are white with brownish, ruddy or grey blotches particularly at the wide end. The egg size ranges from an average 20.2 x 14.0 mm (0.80 x 0.55 in) with a weight of 2.08 g (0.073 oz) for the Eurasian Crag Martin to 17.7 x 13.0 mm (0.70 x 0.51 in) with a weight of 1.57 g (0.06 oz) for the Dusky Crag Martin. Both adults incubate the eggs for 13–19 days to hatching, and feed the chicks at least ten times an hour until they fledge 24–27 days later. The fledged young continue to be fed by the parents for some time after they can fly.
es and other flies
, aerial spiders, ant
s and beetle
s. Martins often feed alone, but sizeable groups may congregate if food is abundant, such as where insects are fleeing grass fire
s. The Eurasian Crag Martin may take aquatic species such as stoneflies
, caddisflies and pond skaters. Cliff faces generate standing wave
s in the airflow which concentrate insects near vertical areas. Crag martins exploit the area close to the cliff when they hunt, relying on their high manoeuvrability and ability to perform tight turns.
or Eurasian Hobby
that specialise in catching swallows and martins in flight, and by other falcons such as the Peregrine
and Taita Falcon
s. Crows may attack migrating Eurasian Crag Martins, and that species also treats Common Kestrel
s, Eurasian Sparrowhawks, Eurasian Jay
s and Common Raven
s as predators if they approach the nesting cliffs. The Dusky Crag Martin has been recorded in the diet of the Greater False Vampire Bat, Megaderma lyra.
Crag martins may host parasites, including blood-sucking mites of the genus Dermanyssus such as D. chelidonis, and the nasal mite Ptilonyssus ptyonoprognes. Invertebrate species first found in nests of crag martin species include the tick Argas (A.) africolumbae from a Rock Martin nest and the fly Ornithomya rupes and the flea Ceratophyllus nanshanensis from European Crag Martin nests.
, south into lowland Laos, and westwards to the hills and plains of Sindh
. There is also a recent unconfirmed report from Cambodia. Their large ranges and presumed high numbers mean that none of the crag martins are considered to be threatened, and all are classed as Least Concern
on the IUCN Red List
.
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...
birds in the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Ptyonoprogne of the swallow
Swallow
The swallows and martins are a group of passerine birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding...
family. They are the Eurasian Crag Martin (P. rupestris), the Rock Martin (P. fuligula) and the Dusky Crag Martin
Dusky Crag Martin
The Dusky Crag Martin is a small passerine bird in the swallow family. It is about 13 cm long with a broad body and wings, and a short square tail that has small white patches near the tips of most of its feathers. This martin has sooty-brown upperparts and slightly paler underparts...
(P. concolor). They are closely related to each other, and have formerly sometimes been considered to be one species. They are closely related to the Hirundo
Hirundo
The bird genus Hirundo is a group of passerines in the family Hirundinidae . These are the typical swallows, including the widespread Barn Swallow. Many of this group have blue backs, red on the face and sometimes the rump or nape, and whitish or rufous underparts...
barn swallows and are placed in that genus by some authorities. These are small swallows with brown upperparts, paler underparts without a breast band, and a square tail with white patches. They can be distinguished from each other on size, the colour shade of the upperparts and underparts, and minor plumage details like throat colour. They resemble the Sand Martin
Sand Martin
The Sand Martin is a migratory passerine bird in the swallow family. It has a wide range in summer, embracing practically the whole of Europe and the Mediterranean countries, part of northern Asia and also North America. It winters in eastern and southern Africa, South America and South Asia...
, but are darker below, and lack a breast band.
These are species of craggy mountainous habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s, although all three will also frequent human habitation. The African Rock Martin and the south Asian Dusky Crag Martin are resident, but the Eurasian Crag Martin is a partial migrant
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...
; birds breeding in southern Europe are largely resident, but some northern breeders and most Asian birds are migratory, wintering in north Africa or India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. They do not normally form large breeding colonies, but are more gregarious outside the breeding season. These martins build neat mud nests
Bird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
under cliff
Cliff
In geography and geology, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are formed as erosion landforms due to the processes of erosion and weathering that produce them. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually...
overhangs or in crevices in their mountain homes, and have readily adapted to the artificial cliffs provided by buildings and motorway bridges. Up to five eggs
Bird egg
Bird eggs are laid by females and incubated for a time that varies according to the species; a single young hatches from each egg. Average clutch sizes range from one to about 17...
, white with dark blotches at the wider end, may be laid, and a second clutch is common. Ptyonoprogne martins feed mainly on 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 caught in flight, and patrol cliffs near the breeding site with a slow hunting flight as they seek their prey. They may be hunted by falcon
Falcon
A falcon is any species of raptor in the genus Falco. The genus contains 37 species, widely distributed throughout Europe, Asia, and North America....
s and infected with mite
Mite
Mites, along with ticks, are small arthropods belonging to the subclass Acari and the class Arachnida. The scientific discipline devoted to the study of ticks and mites is called acarology.-Diversity and systematics:...
s and flea
Flea
Flea is the common name for insects of the order Siphonaptera which are wingless insects with mouthparts adapted for piercing skin and sucking blood...
s, but their large ranges and populations mean that none of the crag martins are considered to be threatened, and all are classed as Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
on the IUCN Red List
IUCN 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...
.
Taxonomy
The three Ptyonoprogne species are the Eurasian Crag Martin (P. rupestris) described as Hirundo rupestris by Italian naturalist Giovanni Antonio ScopoliGiovanni Antonio Scopoli
Giovanni Antonio Scopoli was an Italian physician and naturalist.-Biography:...
in 1769, the Rock Martin (P. fuligula), described by German zoologist Martin Lichtenstein
Martin Lichtenstein
Martin Hinrich Carl Lichtenstein was a German physician, explorer, zoologist, and herpetologist.-Biography:...
in 1842, and the Dusky Crag Martin
Dusky Crag Martin
The Dusky Crag Martin is a small passerine bird in the swallow family. It is about 13 cm long with a broad body and wings, and a short square tail that has small white patches near the tips of most of its feathers. This martin has sooty-brown upperparts and slightly paler underparts...
(P. concolor) formally described in 1832 as Hirundo concolor by British soldier and ornithologist William Henry Sykes
William Henry Sykes
Colonel William Henry Sykes, FRS was an Indian Army officer, politician and ornithologist.Sykes was born near Bradford in Yorkshire, and joined the Bombay Army, a part of the armed forces of the Honourable East India Company, in 1804, returning to Britain in 1837...
. They were moved to the new genus Ptyonoprogne by German ornithologist Heinrich Gustav Reichenbach
Heinrich Gustav Reichenbach
Heinrich Gustav Reichenbach was an ornithologist, botanist and the foremost German orchidologist of the 19th century...
in 1850. The genus name is derived from the Greek ptuon (φτυον), "a fan", referring to the shape of the opened tail, and Procne (Πρόκνη), a mythological girl who was turned into a swallow.
These are members of the swallow family of birds, and are placed in the Hirundininae subfamily which comprises all swallows and martins except the very distinctive river martin
River martin
The river martins form a distinctive subfamily Pseudochelidoninae within the swallow and martin bird family Hirundinidae. The two species are the African River Martin Pseudochelidon eurystomina, found in the Congo and Gabon, and the White-eyed River Martin Pseudochelidon sirintarae, known only from...
s. DNA 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...
studies suggest that there are three major groupings within the Hirundininae, broadly correlating with the type of nest built. The groups are the "core martins" including burrowing species like the Sand Martin
Sand Martin
The Sand Martin is a migratory passerine bird in the swallow family. It has a wide range in summer, embracing practically the whole of Europe and the Mediterranean countries, part of northern Asia and also North America. It winters in eastern and southern Africa, South America and South Asia...
, the "nest-adopters", which are birds like the Tree Swallow
Tree Swallow
The Tree Swallow, Tachycineta bicolor, is a migratory passerine bird that breeds in North America and winters in Mexico, Central America and the Caribbean. It is a very rare vagrant to western Europe....
that utilise natural cavities, and the "mud nest builders". Ptyonoprogne species construct a mud nest and therefore belong to the latter group; They resemble the Hirundo
Hirundo
The bird genus Hirundo is a group of passerines in the family Hirundinidae . These are the typical swallows, including the widespread Barn Swallow. Many of this group have blue backs, red on the face and sometimes the rump or nape, and whitish or rufous underparts...
species in that they make open cup nests, whereas Delichon
Delichon
Delichon is a small genus of passerine birds that belongs to the swallow family and contains three species named as house martins. These are chunky, bull-headed and short-tailed birds, blackish-blue above with a contrasting white rump, and with white or grey underparts. They have feathering on the...
martins build closed cups, and the Cecropis
Cecropis
Cecropis is a genus of large swallows found in Africa and tropical Asia. The Red-rumped Swallow's range also extends into southern Europe. This genus is frequently subsumed into the larger genus Hirundo.The species are:...
and Petrochelidon
Petrochelidon
Petrochelidon is a genus of birds known as cliff-nesting swallows.It contains the following species:-Species in taxonomic order:* Red-throated Cliff Swallow * Preuss's Cliff Swallow...
swallows, have retort-like
Retort
In a chemistry laboratory, a retort is a glassware device used for distillation or dry distillation of substances. It consists of a spherical vessel with a long downward-pointing neck. The liquid to be distilled is placed in the vessel and heated...
closed nests with an entrance tunnel. The genus Ptyonoprogne is closely related to the larger swallow genus Hirundo into which it is often subsumed, but a DNA analysis showed that a coherent enlarged Hirundo genus should contain all the mud-builder genera. Although the nests of the Ptyonoprogne crag martins resembles those of typical Hirundo species like the Barn Swallow
Barn Swallow
The Barn Swallow is the most widespread species of swallow in the world. It is a distinctive passerine bird with blue upperparts, a long, deeply forked tail and curved, pointed wings. It is found in Europe, Asia, Africa and the Americas...
, the DNA research showed that if the Delichon
Delichon
Delichon is a small genus of passerine birds that belongs to the swallow family and contains three species named as house martins. These are chunky, bull-headed and short-tailed birds, blackish-blue above with a contrasting white rump, and with white or grey underparts. They have feathering on the...
house martins are considered to be a separate genus, as is normally the case, Cecropis
Cecropis
Cecropis is a genus of large swallows found in Africa and tropical Asia. The Red-rumped Swallow's range also extends into southern Europe. This genus is frequently subsumed into the larger genus Hirundo.The species are:...
, Petrochelidon
Petrochelidon
Petrochelidon is a genus of birds known as cliff-nesting swallows.It contains the following species:-Species in taxonomic order:* Red-throated Cliff Swallow * Preuss's Cliff Swallow...
and Ptyonoprogne should also be split off.
These three species have formerly been considered conspecific; conversely, the small, pale northern subspecies of Rock Martin found in the mountains of North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
and the Arabia
Arabian Peninsula
The Arabian Peninsula is a land mass situated north-east of Africa. Also known as Arabia or the Arabian subcontinent, it is the world's largest peninsula and covers 3,237,500 km2...
n peninsular are sometimes split as the Pale Crag Martin, Ptyonoprogne obsoleta.
Description
These martins are 12–15 cm (4.7–5.9 in) long with drab brown or grey plumage and a short square tail that has small white patches near the tips of all but the central and outermost pairs of feathers. The eyes are brown, the small bill is mainly black, and the legs are brownish-pink. The sexes are similar, but juveniles show pale edges to the upperparts and flight feathers. The species differ in plumage shades and size, Eurasian Crag Martin being significantly larger than the others. The flight is slow, with rapid wing beats interspersed with flat-winged glides. The songs of these birds are simple twitterings, and contact calls include a high-pitched twee or chi, chi, and a tshir or trrt call like that of the House Martin.These drab martins can only be confused with each other, or with sand martins of the genus Riparia. Even the smaller Ptyonoprogne species are slightly larger and more robust than the Sand Martin
Sand Martin
The Sand Martin is a migratory passerine bird in the swallow family. It has a wide range in summer, embracing practically the whole of Europe and the Mediterranean countries, part of northern Asia and also North America. It winters in eastern and southern Africa, South America and South Asia...
and Brown-throated Sand Martin
Brown-throated Sand Martin
The Brown-throated Sand Martin, Brown-throated Martin or Plain Martin, Riparia paludicola, is a small passerine bird in the swallow family...
, and have the white tail spots which are absent from the Riparia martins. Where the ranges of Ptyonoprogne species overlap, the Eurasian Crag Martin is darker, browner and 15% larger than the Rock Martin, and larger and paler, particularly on its underparts, than the Dusky Crag Martin. The white tail spots of the Eurasian Crag Martin are significantly larger than those of both its relatives. In the east of its range, the Rock Martin always has lighter, more contrasted underparts than the Dusky Crag Martin.
Distribution and habitat
These are exclusively Old World species. The Rock Martin breeds throughout Africa and through the Middle East as far as Afghanistan and Pakistan, and is replaced by the Dusky Crag Martin further east in India and IndochinaIndochina
The Indochinese peninsula, is a region in Southeast Asia. It lies roughly southwest of China, and east of India. The name has its origins in the French, Indochine, as a combination of the names of "China" and "India", and was adopted when French colonizers in Vietnam began expanding their territory...
. The Eurasian Crag Martin breeds from Iberia
Iberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...
and northwesternmost Africa through southern Europe, the Persian Gulf
Persian Gulf
The Persian Gulf, in Southwest Asia, is an extension of the Indian Ocean located between Iran and the Arabian Peninsula.The Persian Gulf was the focus of the 1980–1988 Iran-Iraq War, in which each side attacked the other's oil tankers...
and 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...
to southwestern and northeastern China. Northern populations of the Eurasian Crag Martin are 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...
, with European birds wintering in north Africa, Senegal, Ethiopia and the Nile Valley
Nile
The Nile is a major north-flowing river in North Africa, generally regarded as the longest river in the world. It is long. It runs through the ten countries of Sudan, South Sudan, Burundi, Rwanda, Democratic Republic of the Congo, Tanzania, Kenya, Ethiopia, Uganda and Egypt.The Nile has two major...
, and Asian breeders going to southern China, the Indian subcontinent and the Middle East
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
. Some European birds stay north of the Mediterranean, and, like populations in warmer areas such as India, Turkey and Cyprus, just move to lower ground after breeding. The Dusky Crag Martin and Rock are largely resident apart from local movements after breeding, when many birds descend to lower altitudes, although some pale northern Rock Martins from North African and southern Arabian may winter further south alongside the local subspecies in Ethiopia, Mali and Mauritania.
The crag martins mainly breed on dry, warm and sheltered cliffs in mountainous areas with crags and gorges, and the Eurasian Crag Martin reaches 5,000 m (16,500 ft) in Central Asia. The use of buildings as artificial cliffs has enabled breeding expansion into lowland areas, particularly for the two tropical species, and the Rock Martin breeds in desert towns. In South Asia, migrant Eurasian birds sometimes join with flocks of the Dusky Crag Martin and roost communally on ledges of cliffs or buildings in winter.
Breeding
Bird colony
A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in close proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony...
may form. These are more common south of the Sahara, where up to 40 Rock Martin pairs together have been recoded. Crag martins aggressively defend their nesting territory against conspecifics and other species. The nest, built by both adults over several weeks, is made from several hundred mud pellets and lined with soft dry grass or sometimes feathers. It may be a half-cup when constructed under an overhang on a vertical wall or cliff, or shaped as a bowl like that of the Barn Swallow when placed on a sheltered ledge. The nest may be built on a rock cliff face, in a crevice or on a man-made structure, and is re-used for the second brood and in subsequent years. Usually two broods are raised, and the Rock Martin may nest for a third time in a season.
The clutch is two to five eggs that are white with brownish, ruddy or grey blotches particularly at the wide end. The egg size ranges from an average 20.2 x 14.0 mm (0.80 x 0.55 in) with a weight of 2.08 g (0.073 oz) for the Eurasian Crag Martin to 17.7 x 13.0 mm (0.70 x 0.51 in) with a weight of 1.57 g (0.06 oz) for the Dusky Crag Martin. Both adults incubate the eggs for 13–19 days to hatching, and feed the chicks at least ten times an hour until they fledge 24–27 days later. The fledged young continue to be fed by the parents for some time after they can fly.
Feeding
Ptyonoprogne martins feed mainly on insects caught in flight, although they will occasionally feed on the ground. When breeding, birds often fly back and forth along a rock face catching insects in their bills and usually feeding close to the nesting territory. To maintain the high frequency with which the young are fed, the adults mainly forage in the best hunting zones in the immediate vicinity of the nest, since the further they have to fly to catch insects, the longer it would take to bring food to the chicks in the nest. At other times, they may hunt low over open ground. The insects taken depend on what is locally available, but may include mosquitoMosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
es and other flies
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...
, aerial spiders, ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s and beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
s. Martins often feed alone, but sizeable groups may congregate if food is abundant, such as where insects are fleeing grass fire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...
s. The Eurasian Crag Martin may take aquatic species such as stoneflies
Plecoptera
Plecoptera are an order of insects, commonly known as stoneflies. There are some 3,500 described species worldwide, with new species still being discovered. Stoneflies are found worldwide, except Antarctica...
, caddisflies and pond skaters. Cliff faces generate standing wave
Standing wave
In physics, a standing wave – also known as a stationary wave – is a wave that remains in a constant position.This phenomenon can occur because the medium is moving in the opposite direction to the wave, or it can arise in a stationary medium as a result of interference between two waves traveling...
s in the airflow which concentrate insects near vertical areas. Crag martins exploit the area close to the cliff when they hunt, relying on their high manoeuvrability and ability to perform tight turns.
Predators and parasites
The crag martins may be hunted by fast, agile birds of prey such as the African HobbyAfrican Hobby
The African Hobby is a species of bird of prey in the Falconidae family.It is found in Angola, Benin, Botswana, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Ethiopia, Gabon, Gambia, Ghana, Guinea,...
or Eurasian Hobby
Eurasian Hobby
The Eurasian Hobby , or just simply Hobby, is a small slim falcon. It belongs to a rather close-knit group of similar falcons often considered a subgenus Hypotriorchis.-Description:...
that specialise in catching swallows and martins in flight, and by other falcons such as the Peregrine
Peregrine Falcon
The Peregrine Falcon , also known as the Peregrine, and historically as the Duck Hawk in North America, is a widespread bird of prey in the family Falconidae. A large, crow-sized falcon, it has a blue-gray back, barred white underparts, and a black head and "moustache"...
and Taita Falcon
Taita Falcon
The Taita Falcon is one of the smallest falcons in the Southern African Sub-region. It was first described from the Taita Hills of Kenya from which it derives its name. It is spread throughout the eastern portion of subsaharan Africa but is mostly found in Kenya...
s. Crows may attack migrating Eurasian Crag Martins, and that species also treats Common Kestrel
Common Kestrel
The Common Kestrel is a bird of prey species belonging to the kestrel group of the falcon family Falconidae. It is also known as the European Kestrel, Eurasian Kestrel, or Old World Kestrel. In Britain, where no other brown falcon occurs, it is generally just called "the kestrel".This species...
s, Eurasian Sparrowhawks, Eurasian Jay
Eurasian Jay
The Eurasian Jay is a species of bird occurring over a vast region from Western Europe and north-west Africa to the Indian Subcontinent and further to the eastern seaboard of Asia and down into south-east Asia...
s and Common Raven
Common Raven
The Common Raven , also known as the Northern Raven, is a large, all-black passerine bird. Found across the northern hemisphere, it is the most widely distributed of all corvids...
s as predators if they approach the nesting cliffs. The Dusky Crag Martin has been recorded in the diet of the Greater False Vampire Bat, Megaderma lyra.
Crag martins may host parasites, including blood-sucking mites of the genus Dermanyssus such as D. chelidonis, and the nasal mite Ptilonyssus ptyonoprognes. Invertebrate species first found in nests of crag martin species include the tick Argas (A.) africolumbae from a Rock Martin nest and the fly Ornithomya rupes and the flea Ceratophyllus nanshanensis from European Crag Martin nests.
Status
All three species have extensive ranges and large populations, and the increasing use of artificial nest sites has enabled range expansion. The Rock Martin often breeds in lowland and desert towns, the Eurasian Crag Martin's range is expanding in Austria, Switzerland, the former Yugoslavia, Romania, and Bulgaria, and the Dusky Crag Martin is spreading northeastwards into GuangxiGuangxi
Guangxi, formerly romanized Kwangsi, is a province of southern China along its border with Vietnam. In 1958, it became the Guangxi Zhuang Autonomous Region of the People's Republic of China, a region with special privileges created specifically for the Zhuang people.Guangxi's location, in...
, south into lowland Laos, and westwards to the hills and plains of Sindh
Sindh
Sindh historically referred to as Ba'ab-ul-Islam , is one of the four provinces of Pakistan and historically is home to the Sindhi people. It is also locally known as the "Mehran". Though Muslims form the largest religious group in Sindh, a good number of Christians, Zoroastrians and Hindus can...
. There is also a recent unconfirmed report from Cambodia. Their large ranges and presumed high numbers mean that none of the crag martins are considered to be threatened, and all are classed as Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
on the IUCN Red List
IUCN 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...
.