Bornean Bristlehead
Encyclopedia
The Bornean Bristlehead (Pityriasis gymnocephala), also variously known as the Bristled Shrike, Bald-headed Crow or the Bald-headed Wood-Shrike, is the only member of the passerine
family
Pityriaseidae and genus Pityriasis. It is an enigmatic and uncommon species of the rainforest canopy of Borneo
.
or the Corvidae
. A more recent suggestion has been to include it in the Tephrodornithidae, a new family that includes Hemipus and Tephrodornis
.
shafts, hence the name 'Bristlehead'. Juveniles have black thighs, red ear-coverts, a red eye-ring, just a few red feathers on the head and undeveloped 'bristles'.
It is a noisy species making a variety of unmusical calls, including distinctive high-pitched nasal whining notes interspersed with harsher notes, chattering noises, whistles, honks and chortles.
, throughout the lowlands of which it has been recorded up to 1200 m asl
, though its distribution is sparse, patchy and unpredictable. It may be found in both primary and secondary lowland forests, including peat swamp forest
s, mixed dipterocarp forests and mangrove
s.
s, drongo
s, trogon
s, woodpecker
s and hornbill
s in mixed-species feeding flock
s. Its movements in the canopy are slow and heavy and it flies with a fast, shallow wing-beat.
s, especially orthoptera
ns, phasmids
, beetle
s, lepidoptera
ns, cicada
s, cockroach
es, termite
s and spider
s which it gleans from arboreal foliage, twigs, branches and trunks. It will also eat small vertebrates and fruit.
of lowland primary forest and burning of peat swamp forest, and the species has almost certainly undergone a population decline. However, it also occurs in less affected forests on slopes so is classified as Near Threatened
.
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...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Pityriaseidae and genus Pityriasis. It is an enigmatic and uncommon species of the rainforest canopy of Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
.
Taxonomy
The relationships of this species have been controversial. At times it has been placed in the Prionopidae, the Cracticidae, the ArtamidaeArtamidae
The family Artamidae gathers together 20 species of mostly crow-like birds native to Australasia and nearby areas.There are two subfamilies: Artaminae, the woodswallows, are sombre-coloured, soft-plumaged birds that have a brush-tipped tongue but seldom use it for gathering nectar. Instead, they...
or the Corvidae
Corvidae
Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs and nutcrackers. The common English names used are corvids or the crow family , and there are over 120 species...
. A more recent suggestion has been to include it in the Tephrodornithidae, a new family that includes Hemipus and Tephrodornis
Tephrodornis
Tephrodornis is a bird genus in the helmetshrike family Prionopidae, commonly known as the woodshrikes. They were formerly placed in the Campephagidae by some, as they are far more conventional in habitus than the rather bizarre typical helmetshrikes of genus Prionops.There are only two species:*...
.
Description
The Bristlehead is a medium-sized (25 centimetres (9.8 in) in length) black or dark grey bird, with red thighs and a red head, throat and neck, with grey ear-coverts and a featherless yellow crown. There is a white wing-patch, visible in flight, and females also have red spots on the flanks. It has a massive heavy black hooked bill and a short tail, giving it a chunky appearance. The crown is covered by short (3–4 mm) yellow or straw-coloured skin projections like bare featherFeather
Feathers are one of the epidermal growths that form the distinctive outer covering, or plumage, on birds and some non-avian theropod dinosaurs. They are considered the most complex integumentary structures found in vertebrates, and indeed a premier example of a complex evolutionary novelty. They...
shafts, hence the name 'Bristlehead'. Juveniles have black thighs, red ear-coverts, a red eye-ring, just a few red feathers on the head and undeveloped 'bristles'.
It is a noisy species making a variety of unmusical calls, including distinctive high-pitched nasal whining notes interspersed with harsher notes, chattering noises, whistles, honks and chortles.
Distribution and habitat
The Bristlehead is endemic to the island of BorneoBorneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
, throughout the lowlands of which it has been recorded up to 1200 m asl
Above mean sea level
The term above mean sea level refers to the elevation or altitude of any object, relative to the average sea level datum. AMSL is used extensively in radio by engineers to determine the coverage area a station will be able to reach...
, though its distribution is sparse, patchy and unpredictable. It may be found in both primary and secondary lowland forests, including peat swamp forest
Peat swamp forest
Peat swamp forests are tropical moist forests where waterlogged soils prevent dead leaves and wood from fully decomposing, which over time creates a thick layer of acidic peat...
s, mixed dipterocarp forests and mangrove
Mangrove
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes N and S...
s.
Behaviour
The Bristlehead is a sociable species which often moves steadily in small garrulous flocks of 6-10 birds in the mid and upper canopy of the forest, sometimes accompanied by other large forest birds such as malkohas, babblerOld World babbler
The Old World babblers or timaliids are a large family of mostly Old World passerine birds. They are rather diverse in size and coloration, but are characterised by soft fluffy plumage. These are birds of tropical areas, with the greatest variety in Southeast Asia and the Indian Subcontinent...
s, drongo
Drongo
The drongos are a family of small passerine birds of the Old World tropics, the Dicruridae. This family was sometimes much enlarged to include a number of largely Australasian groups, such as the Australasian fantails, monarchs and paradise flycatchers...
s, trogon
Trogon
The trogons and quetzals are birds in the order Trogoniformes which contains only one family, the Trogonidae. The family contains 39 species in eight genera. The fossil record of the trogons dates back 49 million years to the mid-Eocene. They might constitute a member of the basal radiation of...
s, woodpecker
Woodpecker
Woodpeckers are near passerine birds of the order Piciformes. They are one subfamily in the family Picidae, which also includes the piculets and wrynecks. They are found worldwide and include about 180 species....
s and hornbill
Hornbill
Hornbills are a family of bird found in tropical and subtropical Africa, Asia and Melanesia. They are characterized by a long, down-curved bill which is frequently brightly-colored and sometimes has a casque on the upper mandible. Both the common English and the scientific name of the family...
s in 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. Its movements in the canopy are slow and heavy and it flies with a fast, shallow wing-beat.
Feeding
It feeds mainly on large invertebrateInvertebrate
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...
s, especially orthoptera
Orthoptera
Orthoptera is an order of insects with paurometabolous or incomplete metamorphosis, including the grasshoppers, crickets and locusts.Many insects in this order produce sound by rubbing their wings against each other or their legs, the wings or legs containing rows of corrugated bumps...
ns, phasmids
Phasmatodea
The Phasmatodea are an order of insects, whose members are variously known as stick insects , walking sticks or stick-bugs , phasmids, ghost insects and leaf insects...
, 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, lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
ns, cicada
Cicada
A cicada is an insect of the order Hemiptera, suborder Auchenorrhyncha , in the superfamily Cicadoidea, with large eyes wide apart on the head and usually transparent, well-veined wings. There are about 2,500 species of cicada around the world, and many of them remain unclassified...
s, cockroach
Cockroach
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations...
es, termite
Termite
Termites are a group of eusocial insects that, until recently, were classified at the taxonomic rank of order Isoptera , but are now accepted as the epifamily Termitoidae, of the cockroach order Blattodea...
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 which it gleans from arboreal foliage, twigs, branches and trunks. It will also eat small vertebrates and fruit.
Breeding
Breeding behaviour is largely unknown, though an oviduct egg was described as being white with grey and brown spots and with dimensions of 31 x 25 mm. A sighting of two apparent females feeding a fledgling has been interpreted as suggesting communal breeding. Birds have also been seen in flight carrying nesting material.Conservation
The main threat to the Bristlehead comes from habitat destruction through loggingLogging
Logging is the cutting, skidding, on-site processing, and loading of trees or logs onto trucks.In forestry, the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard...
of lowland primary forest and burning of peat swamp forest, and the species has almost certainly undergone a population decline. However, it also occurs in less affected forests on slopes so is classified as Near Threatened
Near Threatened
Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status...
.
