The Australasian bittern (''Botaurus poiciloptilus''), also known as the brown bittern or matuku hūrepo, and also nicknamed the " bunyip bird", is a large bird in the heron family Ardeidae. A secretive bird with a distinctive booming call, it is more often heard than seen. Australasian bitterns are endangered in both Australia and New Zealand.

Taxonomy

German zoologist Johann Georg Wagler described the Australasian bittern in 1827. It is one of four similarly-plumaged species in the genus '' Botaurus''.

Description

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.

Behaviour

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.

Distribution and habitat

It is found in south-western and south-eastern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

, Tasmania, New Zealand,

New Caledonia ) , anthem = "" , image_map = New Caledonia on the globe (small islands magnified) (Polynesia centered).svg , map_alt = Location of New Caledonia , map_caption = Location of New Caledonia , mapsize = 290px , subdivision_type = Sovereign st ...

and Ouvea. Populations in Australia and New Zealand have declined in the 20th century. It is a

cryptic Cryptic may refer to: In science: * Cryptic species complex, a group of species that are very difficult to distinguish from one another * Crypsis, the ability of animals to blend in to avoid observation * Cryptic era, earliest period of the Earth ...

and partly nocturnal species that inhabits densely vegetated wetlands.

Status and conservation

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 The ''Flora and Fauna Guarantee Act 1988'', also known as the ''FFG Act'', is an act of parliament, act of the Victorian Government designed to protect species, genetic material and habitats, to prevent extinction and allow maximum genetic diver ...

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.

Important bird areas

BirdLife International BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding ...

has identified the following sites, all of which are in Australia, as being important for Australasian bittern conservation: ;New South Wales *

Fivebough and Tuckerbil Swamps Fivebough and Tuckerbil Wetlands are two wetland sites within the Riverina and Murrumbidgee Irrigation Area (MIA), near Leeton, New South Wales, Leeton in New South Wales, Australia. Both Fivebough and Tuckerbil sites form Crown land, Crown res ...

* Griffith Wetlands * Gwydir Wetlands * Hastings-Macleay * Hunter Estuary * Macquarie Marshes * Narran Wetlands ;Tasmania *

Egg Islands The Egg Islands are a small group of low-lying estuarine islands in the tidal lower reaches of the Huon River of south-east Tasmania, Australia. They face the town of Franklin which lies on the western bank of the river. Birds The islands hav ...

;Victoria * Barmah-Millewa * Bellarine Wetlands * Carrum Wetlands (

Edithvale-Seaford Wetlands The Edithvale-Seaford Wetlands is a collection of principally freshwater swamps and marshlands totalling in southeastern Melbourne, Victoria, Australia, about southeast of Melbourne CBD. It is the largest natural wetland of its type in the ...

and

Eastern Treatment Plant The Eastern Treatment Plant is an sewage treatment plant, located in the suburb of Bangholme in Victoria, Australia, southeast of Melbourne's central business district. The plant was built in 1975 and is owned by Melbourne Water. Following tr ...

) * Discovery Bay to Piccaninnie Ponds * Lower Brodribb River * North Victorian Wetlands *

Yambuk Yambuk is a town in Victoria (Australia), Victoria, Australia. The name Yambuk is an Australian Aboriginal languages, Aboriginal word thought to mean "red kangaroo", "full moon" or "big water". Shell middens in the limestone cliffs to the eas ...

Tootgarook Swamp Tootgarook is a suburb on the Mornington Peninsula in Melbourne, Victoria, Australia, south of Melbourne's Central Business District, located within the Shire of Mornington Peninsula local government area. Tootgarook recorded a population of 3, ...

;South Australia * Coorong * Gulf St Vincent * Lake Hawdon System * Lakes Alexandrina and Albert ;Western Australia *

Benger Swamp Benger Swamp is a wetland located on the Swan Coastal Plain, in south-west Western Australia. The wetland is situated west of Benger, east of the coastal town of Binningup, south-west of Harvey, and south of Perth. Some 89% of the swamp ...

* Lake Pleasant View System * Muir-Unicup Wetlands * Owingup Swamp and Boat Harbour Wetlands * Two Peoples Bay and Mount Manypeaks Botaurus poiciloptilus (AM LB8847) (cropped)

Botaurus poiciloptilus (AM LB8847) (cropped)

Gallery

File:Bitterngould.jpg, Painting by John Gould File:Australasian Bittern (Botaurus poiciloptilus) in the grass.jpg, In the grass, Leeton, New South Wales, Australia File:WRMbittern.jpg, Mounted bittern in the collection of the

Whanganui Regional Museum The Whanganui Regional Museum in Whanganui, New Zealand, has an extensive collection of natural and human-history objects. The emphasis is on items from the Manawatu-Wanganui region, but the collection also includes objects of national and inter ...

References

External links

* Radio New Zealand ''Our Changing World'' programm
"Booming Bitterns", 3 February 2016
* Australasian bitterns discussed on Radio NZ ''Critter of the Week''
4 Dec 2015
{{Taxonbar, from=Q783076

Australasian bittern The Australasian bittern (''Botaurus poiciloptilus''), also known as the brown bittern or matuku hūrepo, and also nicknamed the "bunyip bird", is a large bird in the heron family Ardeidae. A secretive bird with a distinctive booming call, it is ...

Birds of Oceania Endangered fauna of Australia