The 15 to 20 species of small passerine birds in the gnatcatcher family occur in North and South America (except for the far south and the high Andean regions). Most species of this mainly tropical and subtropical group are resident, but the blue-grey gnatcatcher of the United States and southern Canada migrates south in winter. They are close relatives of the wrens.
|California gnatcatcher (Polioptila californica)|
These dainty birds are intermediate between Old World warblers and wrens in their structure and habits, moving restlessly through foliage seeking insects. The gnatcatchers are mainly soft bluish grey in colour, and have the typical insectivore's long sharp bill. Many species have distinctive black head patterns (especially males) and long, regularly cocked, black-and-white tails. The skulking gnatwrens are browner, more thickset, and with proportionally shorter tails and longer bills.
They are distributed from North to South America, with the exception of the far south and high Andean regions. Gnatwrens typically occur in the undergrowth of dense, often humid, forest, while gnatcatchers, depending on the species involved, occur in anything from dry scrubby habitats (e.g. the California gnatcatcher) to the canopy of humid Amazonian forest (e.g. the Guianan gnatcatcher). The North American species nest in bushes or trees, but the breeding behavior of several of the Neotropical species is essentially unknown.
|Relatives of the gnatcatchers in the superfamily Certhioidea.|
A species new to science, the critically endangered Iquitos gnatcatcher Polioptila clementsi, was first described in 2005. This species is a member of the Guianan gnatcatcher Polioptila guianensis complex, which recently has been proposed split into three species (four with the Iquitos gnatcatcher), but not all authorities have accepted this (e.g. SACC). Furthermore, other groups should possibly be split, notably the tropical gnatcatcher Polioptila plumbea and masked gnatcatcher Polioptila dumicola complexes, but at present scientific papers on these matters are lacking.
The family contains 20 species divided into 3 genera:
The black-capped gnatcatcher (Polioptila nigriceps) is a very small songbird.Black-tailed gnatcatcher
The black-tailed gnatcatcher (Polioptila melanura) is a small, insectivorous bird which ranges throughout the Sonoran and Chihuahuan Deserts of the southwestern United States and northern Mexico. It is nonmigratory and found in arid desert areas year-round.Blue-gray gnatcatcher
The blue-gray gnatcatcher or blue-grey gnatcatcher (Polioptila caerulea) is a very small songbird, 10–13 cm (3.9–5.1 in) in length and weighing only 5–7 g (0.18–0.25 oz). Adult males are blue-gray on the upperparts with white underparts, have a slender dark bill, and a long black tail edged in white. Females are less blue, while juveniles are greenish-gray. Both sexes have a white eye ring.
The blue-gray gnatcatcher's breeding habitat includes open deciduous woods and shrublands in southern Ontario, the eastern and southwestern United States, and Mexico. Though gnatcatcher species are common and increasing in number while expanding to the northeast, it is the only one to breed in Eastern North America. Both parents build a cone-like nest on a horizontal tree branch, and share feeding the young. The incubation period is 13 days for both sexes, and two broods may be raised in a season.
These birds migrate to the southern United States, Mexico, northern Central America-(Belize, Guatemala, and Honduras), Cuba, Bahamas, Turks and Caicos Islands, and the Cayman Islands.
They forage actively in trees or shrubs, mainly eating insects, insect eggs and spiders. They may hover over foliage (gleaning), or fly to catch insects in flight (hawking).
The tail is often held upright while defending territory or searching for food.California gnatcatcher
The California gnatcatcher (Polioptila californica) is a small 10.8 cm (4.3 in) long insectivorous bird which frequents dense coastal sage scrub growth. This species was recently split from the similar black-tailed gnatcatcher of the Sonoran and Chihuahuan deserts. This bird is often solitary, but joins with other birds in winter flocks.Creamy-bellied gnatcatcher
The creamy-bellied gnatcatcher (Polioptila lactea) is a species of bird in the family Polioptilidae.
It is found in Argentina, Brazil, and Paraguay.
Its natural habitats are subtropical or tropical moist lowland forest and heavily degraded former forest.
It is threatened by habitat loss.Cuban gnatcatcher
The Cuban gnatcatcher (Polioptila lembeyei) is a species of bird in the family Polioptilidae, the gnatcatchers.
It is endemic to Cuba.
Its natural habitat is xeric scrubland. It is the smallest species in the Polioptilidae family at 10 cm (4 in).Guianan gnatcatcher
The Guianan gnatcatcher (Polioptila guianensis) is a species of bird in the Polioptilidae family. It is found in the canopy in the Amazon rainforest. This relatively plain gnatcatcher formerly included two subspecies that are now treated as separate species:
Rio Negro gnatcatcher, Polioptila facilis, from southern Venezuela and north-western Brazil (north of the Amazon River and west of the Branco River)
Para gnatcatcher, Polioptila paraensis, from the southern Amazon in Brazil (south of the Amazon River)Additionally, the highly threatened Iquitos gnatcatcher is associated with this group.Inambari gnatcatcher
The Inambari gnatcatcher (Polioptila attenboroughi) is a species of bird in the family Polioptilidae. Many authorities consider it a subspecies of the Guianan gnatcatcher (Polioptila guianensis). It is endemic to the Amazon rainforest in Brazil, where it is found in a region south of the Amazon River and west of the Madeira River. It is found in subtropical or tropical moist lowland forests.Iquitos gnatcatcher
The Iquitos gnatcatcher (Polioptila clementsi) is a gnatcatcher described as new to science in 2005. It is currently only known from the Allpahuayo-Mishana National Reserve, west of Iquitos, Peru. The species is a member of the Polioptila guianensis complex. The specific name was chosen to honour the American ornithologist James F. Clements.James Clements
James Franklin "Jim" Clements (October 31, 1927 – June 9, 2005) was an American ornithologist, author and businessman. He was born in New York, United States.
He married Mary Norton and they had two sons. His second marriage, which lasted 14 years, was to Christina. He married a third time, to Karen.
He received his PhD from California Western University in 1975. His thesis became the first edition of his Birds of the World, A Check List (now in its sixth edition). Clements was mostly finished with the sixth edition at the time of his death, and responsibility for the series was taken up by the Cornell Laboratory of Ornithology by arrangement with Clements's widow, Karen. The Ornithology Lab finished the sixth edition, maintains corrections and updates for it, and plans to publish future editions.A bird, the Iquitos gnatcatcher, Polioptila clementsi, is named after him.
He died at Tri-City Hospital, Oceanside, California of complications associated with acute myloid leukemia.Masked gnatcatcher
The masked gnatcatcher (Polioptila dumicola) is a small active insectivorous songbird, found in northern Argentina, Uruguay, Paraguay, Bolivia and southern and central Brazil. It is found in a wide range of semi-open habitats, including dry forest and Cerrado. It is generally fairly common, and consequently considered to be of least concern by BirdLife International and IUCN.
Its jizz is similar to that of other gnatcatchers; a small bird with a relatively long thin bill, a long frequently cocked tail, and grey upperparts. The central rectrices are black, while the outer are white (consequently, the tail appears primarily black from above, white from below), and there is a white patch in the wing (caused by broad white edging to the tertials). Males of the southern and western group (including subspecies saturata), the masked gnatcatchers in the strict sense, have grey underparts and a broad black mask. Females lack the mask, but instead have a black patch behind the eyes on the auriculars. The northern nominate subspecies dumicola is distinctive, with white underparts in both sexes, and a narrow black mask in the male. It may be a separate species, Berlepsch's gnatcatcher.Para gnatcatcher
The Para gnatcatcher (Polioptila paraensis) or Klages's gnatcatcher is a species of bird in the family Polioptilidae. It is found in state of Pará in the southeast Amazonian region of Brazil.
The Para gnatcatcher was formerly treated as a subspecies of the Guianan gnatcatcher (Polioptila guianensis) but is now considered as a separate species based on the difference in morphology and vocalisation.Polioptila
Polioptila is a genus of small insectivorous birds in the family Polioptilidae. They are found in North and South America.
The genus Polioptila was introduced by the English zoologist Philip Sclater in 1855. Although he listed several members, he did not specify a type species. This was designated by the American ornithologist Spencer Baird in 1864 as Montacilla caerulea, Linnaeus, now the blue-grey gnatcatcher, Polioptila caerulea. The name of the genus combines the Ancient Greek words πολιος polios "grey" and πτιλον ptilon "plumage".The genus contains 16 species:
Blue-grey gnatcatcher, Polioptila caerulea
Black-tailed gnatcatcher, Polioptila melanura
California gnatcatcher, Polioptila californica
Cuban gnatcatcher, Polioptila lembeyei
White-lored gnatcatcher, Polioptila albiloris
Yucatan gnatcatcher, Polioptila albiventris
Black-capped gnatcatcher, Polioptila nigriceps
Tropical gnatcatcher, Polioptila plumbea
Creamy-bellied gnatcatcher, Polioptila lactea
Guianan gnatcatcher, Polioptila guianensis
Rio Negro gnatcatcher, Poliptila facilis – split from P. guianensis
Para gnatcatcher, Polioptila paraensis – split from P. guianensis
Inambari gnatcatcher, Polioptila attenboroughi – described in 2013
Iquitos gnatcatcher, Polioptila clementsi – described in 2005
Slate-throated gnatcatcher, Polioptila schistaceigula
Masked gnatcatcher, Polioptila dumicolaRio Negro gnatcatcher
The Rio Negro gnatcatcher (Ramphocaenus facilis) is a species of bird in the family Polioptilidae. It is found in northwest Brazil near the river Rio Negro, a tributary of the Amazon.
The Rio Negro gnatcatcher was formerly treated as a subspecies of the Guianan gnatcatcher (Polioptila guianensis) but is now considered as a separate species based on the significant differences in morphology and vocalisation.Sibley-Monroe checklist 15
The Sibley-Monroe checklist was a landmark document in the study of birds. It drew on extensive DNA-DNA hybridisation studies to reassess the relationships between modern birds.Slate-throated gnatcatcher
The slate-throated gnatcatcher (Polioptila schistaceigula) is a species of bird in the family Polioptilidae.
It is found in Colombia, Ecuador, and Panama.
Its natural habitat is subtropical or tropical moist lowland forests.Tropical gnatcatcher
The tropical gnatcatcher (Polioptila plumbea) is a small active insectivorous songbird, which is a resident species throughout a large part of the Neotropics. There are large geographical variations in its voice and plumage, resulting in some populations sometimes being considered separate species, notably the bilineata group as the white-browed gnatcatcher, and the taxon maior as the Marañón gnatcatcher.White-lored gnatcatcher
The white-lored gnatcatcher (Polioptila albiloris) is a species of bird in the family Polioptilidae.
It is found in Costa Rica, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua.
Its natural habitats are subtropical or tropical dry forests, subtropical or tropical moist lowland forests, subtropical or tropical dry shrubland, and subtropical or tropical high-altitude shrubland.Yucatan gnatcatcher
The Yucatan gnatcatcher (Polioptila albiventris) is a species of bird in the family Polioptilidae.
It is endemic to the Yucatán Peninsula in Mexico. It was previously considered a subspecies of the white-lored gnatcatcher.
Its natural habitats are subtropical or tropical dry forests, subtropical or tropical moist lowland forests, subtropical or tropical dry shrubland, and subtropical or tropical high-altitude shrubland.