Australasian Bittern
Botaurus poiciloptilus
Large, stocky, strongly patterned heron with broad neck and yellow-green legs. Upperparts dark brown, underparts streaked. Usually found in reed beds, where it can be difficult to observe; often forages at night. When disturbed, “freezes,” with head pointing upward (as if trying to blend in with the habitat). Compare young Rufous Night-Heron, which is much smaller, has shorter neck, and tends to roost in trees. Song a very deep, slowly repeated "boom."
识别特征
The length is from 650 to 750 mm with adults being similar between the sexes while the male is significantly larger. The bird has a deep brown upper surface, mauled with buff on wing coverts; face and eyebrow buff, with dark brown stripe running from bill to erectile plumes at sides of neck. Under surface buff, striped with brown. The face skin is a dull green as are the legs and feet, it possesses a dark brown bill, yellow eyes, and the base of the lower mandible is green-yellow.
分类信息
German zoologist Johann Georg Wagler described the Australasian bittern in 1827. It is one of four similarly plumaged species in the genus Botaurus.
- 学名
- Botaurus poiciloptilus
- 命名信息
- (Wagler, 1827)
- 目
- Pelecaniformes
- 科
- Ardeidae
- 属
- Botaurus
分布与栖息地
It is found in south-western and south-eastern Australia, Tasmania, New Zealand, New Caledonia and Ouvea. Populations in Australia and New Zealand have declined in the 20th century. It is a cryptic and partly nocturnal species that inhabits densely vegetated wetlands.
- 迁徙
- Resident species
行为
It feeds on aquatic animals such as frogs, eels and freshwater crustaceans. It is a solitary nester on the ground in dense wetland vegetation on trampled reeds and other plants. Monitoring of this species mainly relies upon the ability to count males based on the conspicuous breeding calls of males. Detailed analyses showed that the best time to detect Australasian Bitterns was 1 hour before sunrise, in September (austral spring), on a moonlit night with no cloud or rain.
保护状况
The principal cause of past and present decline is thought to be wetland drainage and degradation. In Australia it is thought to be particularly sensitive to the destruction of drought refugia. It is listed as endangered on the Environment Protection and Biodiversity Conservation Act 1999. It is listed as threatened on the Victorian Flora and Fauna Guarantee Act of 1988. Under this act, an Action Statement for the recovery and future management of this species has not been prepared. On the 2007 advisory list of threatened vertebrate fauna in Victoria, this species is listed as endangered.<p>BirdLife International has identified the following sites, all of which are in Australia, as being important for Australasian bittern conservation:
- 种群趋势
- declining
照片
分布
鸟叫声
其他鸟类
Jamaican Euphonia
Euphonia jamaica
A very small and active inhabitant of most wooded habitats and gardens where it forages mostly on fruits and flowers. Note this species’ short, stubby bill, and mostly gray head and underparts. The Orangequit is somewhat similar but is readily distinguished by its longer and slightly curved bill. Additionally, male Orangequits are darker gray and have an orange throat, while female Orangequits have brown upperparts. Song is rapid-fire jumble of squeaks, whistles, and buzzes. The call note is a sharp “tseet.” Jamaican Euphonias also give a scratchy, squeaky “bao,” which is given singly, in series, or interjected into songs.
Purple-throated Woodstar
Philodice mitchellii
Woodstars are tiny hummingbirds that fly like bumblebees. Purple-throated is restricted to the west slope of the Andes in Colombia and Ecuador, where it inhabits cloud forest, edges, and second growth from 800–2,000 m. Males have a glittering purple throat, white chest band, fairly long forked tail, and white patches on the sides of the rump. Unlikely to be confused within range. Females are trickier; note the orangey belly with a variable amount of smudgy white in the center (never as extensive as on female White-bellied Woodstar) and the thin whitish line that extends behind the eye and wraps around the neck (not as wide or buffy as on Little Woodstar). Often seen singly feeding in the canopy; visits feeders.
Cassin's Honeybird
Prodotiscus insignis
A small, upright honeyguide of forest and forest edge, where it forages for insects and flycatches into the open. Plumage is a relatively uniform olive-green to green, with a paler throat, small pale eye arcs, and bright white outer tail feathers that are obvious when flying out for insects. Similar to Green-backed Honeyguide and Wahlberg’s Honeyguide, but differs in range, in its overall greenish coloration including the belly, and in its clean white outer tail feathers. Voice is little known, but apparently gives a buzzy trill in flight that rises and falls in pitch.
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