|Pardalotus striatus ornatus with nesting material|
Pardalotes or peep-wrens are a family, Pardalotidae, of very small, brightly coloured birds native to Australia, with short tails, strong legs, and stubby blunt beaks. This family is composed of four species in one genus, Pardalotus, and several subspecies. The name derives from a Greek word meaning "spotted". The family once contained several other species now split into the family Acanthizidae.
Pardalotes spend most of their time high in the outer foliage of trees, feeding on insects, spiders, and above all lerps (a type of sap sucking insect). Their role in controlling lerp infestations in the eucalyptus forests of Australia may be significant. They generally live in pairs or small family groups but sometimes come together into flocks after breeding.
Pardalotes are seasonal breeders in temperate areas of Australia but may breed year round in warmer areas. They are monogamous breeders, and both partners share nest construction, incubation and chick rearing duties. All four species nest in deep horizontal tunnels drilled into banks of earth. Externally about the size of a mouse-hole, they can be very deep, at a metre or more. Some species also nest in tree hollows.
Taxonomy and systematics
The pardalotes consist of four species contained in a single genus, Pardalotus. The placement of the genus has varied, being first placed with the mostly oriental flowerpeckers (Dicaeidae), as both groups are dumpy looking birds with bright plumage. In addition both groups have a reduced tenth primary (one of the flight feathers). Genetic analysis has shown that the two groups are in fact not closely related, and that the pardalotes are instead more closely related another Australian family, the Acanthizidae, which includes the scrubwrens, gerygones and thornbills. The two are sometimes merged into one family; when this is done the combined family is known as Pardalotidae, but the two groups are best separated as two separate families.
Within the family two species, the Forty-spotted Pardalote and the Red-browed Pardalote, are fairly invariant species, but the remaining two species are highly variable and are sometimes treated as more than two species. The Striated Pardalote contains six subspecies that are sometimes elevated to four separate species, and one subspecies of the Spotted Pardalote is sometimes treated as a separate species. Within the family the relationships between the subspecies are unclear, although it is thought that the Forty-spotted Pardalote is closely related to the Spotted Pardalote.
- Spotted Pardalote, Pardalotus punctatus.
- Forty-spotted Pardalote, Pardalotus quadragintus.
- Red-browed Pardalote, Pardalotus rubricatus
- Striated Pardalote, Pardalotus striatus.
The pardalotes are small, compact birds that range in size from 8.5–12 cm (3.3–4.7 in) in length. The Spotted and Striated Pardalotes conform to Bergman's rule and are larger in the south than they are in the north. The males and females are the same size as each other, but there are some differences in the plumage of some species. They have short, square-tipped tails and relatively short rounded wings (which are longer in the more dispersive species). The bill is short, deep and robust, but lacks the rictal bristles that surround the bills of many other insectivorous birds.
Habitat and distribution
The pardalotes are endemic to Australia. The Forty-spotted has the most restricted distribution of the four species, being endemic to Tasmania, in contrast the most widespread species is the Striated Pardalote is found throughout Australia, only absent from some of the driest areas of the inland central and western deserts. The Red-browed Pardalote is widespread in the north and west of Australia, whereas the Spotted Pardalote is found closer to the coast in southern and eastern Australia.
The family are eucalyptus forest specialists. While they may occur in forests and woodlands dominated by other tree types, these are marginal habitats for the family and are seldom used. Pardalotes occupy a wide range of eucalypt habitats, from tall forests with a canopy over 30 m high to low mallee woodlands with a canopy of just 3 m.
Behaviour and ecology
Pardalotes are almost exclusively insectivores. They will occasionally consume some plant materials including seeds, and there has been an observation of one Striated Pardalote beating and then eating a lizard. They feed singly or in pairs during the breeding season, but have been recorded as joining mixed-species feeding flocks in the winter months. The majority of foraging occurs on Eucalyptus, with other trees being used much less frequently, and among the eucalypts trees from the subgenus Symphyomyrtus are preferred. Pardalotes forage by gleaning insects from the foliage, as opposed to sallying and catching insects in the air. While pardalotes may consume a number of different types of insects, lerps, a honeydew casing exuded by insects of the family Psyllidae, form the major component of their diet and the one to which they are most adapted to. These lerps are also highly sought after by the larger honeyeaters, which aggressively defend the resource. A study of pardalotes in Australia estimated that 5% of a pardalote's day is spent evading honeyeater attacks.
- Woinarski, John (2008). "Family Pardalotidae (Pardalotes)". In Josep, del Hoyo; Andrew, Elliott; David, Christie. Handbook of the Birds of the World. Volume 13, Penduline-tits to Shrikes. Barcelona: Lynx Edicions. pp. 390–401. ISBN 978-84-96553-45-3.
- Bell, H.L. (1975). "Eastern Striated Pardalote Eating Lizard". Emu 75 (4): 234–234. doi:10.1071/MU9750234a.
- Bell, H.L. (1980). "Composition and Seasonality of Mixed-Species Feeding Flocks of Insectivorous Birds in the Australian Capital Territory". Emu 80 (4): 227–232. doi:10.1071/MU9800227.
- Woinarski, J.C.Z (1984). "Small birds, Lerp-feeding and the problem of Honeyeaters". Emu 84 (3): 137–141. doi:10.1071/MU9840137.
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