Black-flanked Rock-wallaby
Encyclopedia
The Black-flanked Rock-wallaby (Petrogale lateralis), also known as the Black-footed Rock-wallaby or Warru, is a kind of wallaby
, one of several rock-wallabies
in the genus Petrogale.
This wallaby lives in groups of 10-100 individuals. It usually feeds at night in open areas such as grasses, where it can also find fruit, leaves and a variety of herbs. Because most of its water comes from its diet, it rarely drinks and can conserve water by taking refuge from the heat in rocky caves. It is most active when it leaves its shelter at early-evening. Individuals reach sexual maturity at 1–2 years of age, after which time breeding is continuous, depending on rainfall. Females show embryonic diapause
; the development of the embryo can cease temporarily until environmental conditions become more suitable for its development to complete. The gestation period lasts around 30 days, and like other young marsupials, the young are poorly developed and suckle inside the mother's pouch until they are ready to leave. Unlike other kangaroos and wallabies, mothers leave their young in a sheltered place while they feed.
Predation by introduced foxes and feral cats, habitat damage caused by sheep, goats and rabbits and alteration of fire regimes have caused the population to decline. Several sites where populations occur are protected, and a recovery plan is underway. Fox control has been established at several sites.
in 1842. There are at least two subspecies
besides the nominate subspecies:
A description published as Petrogale lateralis purpureicollis (Purple-necked Rock-wallaby) by Le Souef in 1924 is given in some listings, but this is now regarded as a distinct species. The specimens obtained at the Mcdonnell Ranges, and from the Western Kimberly, are also distinct enough to be separate subspecies of the Black-flanked Rock-wallaby. These populations, and the recognized subspecies, are distinguished by chromosomal
as well as morphological
distinctions.
The Australian Commonwealth Government's Department of Environment and Water Resources lists the black-flanked rock-wallaby as having 'Vulnerable' status and cites various habitats in Western Australia.
The subspecies found at the Recherche Archipelago was assessed as a vulnerable species
in 2006.
In South Australia, the Adelaide Advertiser reported on Monday October 1, 2007 that:
The State Government claims there are just 50 animals left in the wild in South Australia
and the Advertiser article described the process of moving 15 wallabies to captivity in South Australia
, with known native locations to be at Pukatja / Ernabella in the Anangu Pitjantjatjara Yankunytjatjara or 'APY' Lands
and also at New Well, some 300 km east of Adelaide.
Wallaby
A wallaby is any of about thirty species of macropod . It is an informal designation generally used for any macropod that is smaller than a kangaroo or wallaroo that has not been given some other name.-Overview:...
, one of several rock-wallabies
Rock-wallaby
The rock-wallabies are the wallabies of the genus Petrogale.-Description:The medium-sized, often colourful and extremely agile rock-wallabies live where rocky, rugged and steep terrain can provide daytime refuge...
in the genus Petrogale.
Description
The Black-flanked Rock-wallaby is a rather wary animal, with black and grey colouration to blend in with its rocky surroundings, later to lighten in colour during summer. It has short, thick, woolly fur that is particularly dense around the base of the tail, rump and flanks. Its long, brushy tail is quite useful for retaining balance as they hop from one rock to another, and the soles of its feet are highly textured to prevent slipping.This wallaby lives in groups of 10-100 individuals. It usually feeds at night in open areas such as grasses, where it can also find fruit, leaves and a variety of herbs. Because most of its water comes from its diet, it rarely drinks and can conserve water by taking refuge from the heat in rocky caves. It is most active when it leaves its shelter at early-evening. Individuals reach sexual maturity at 1–2 years of age, after which time breeding is continuous, depending on rainfall. Females show embryonic diapause
Embryonic diapause
Delayed Implantation or Embryonic Diapause is a reproductive strategy used by approximately 100 different mammals in seven or eight different orders. In embryonic diapause, the embryo does not immediately implant in the uterus, but is maintained in a state of dormancy. Little to no development...
; the development of the embryo can cease temporarily until environmental conditions become more suitable for its development to complete. The gestation period lasts around 30 days, and like other young marsupials, the young are poorly developed and suckle inside the mother's pouch until they are ready to leave. Unlike other kangaroos and wallabies, mothers leave their young in a sheltered place while they feed.
Predation by introduced foxes and feral cats, habitat damage caused by sheep, goats and rabbits and alteration of fire regimes have caused the population to decline. Several sites where populations occur are protected, and a recovery plan is underway. Fox control has been established at several sites.
Classification
The species was first described by John GouldJohn Gould
John Gould was an English ornithologist and bird artist. The Gould League in Australia was named after him. His identification of the birds now nicknamed "Darwin's finches" played a role in the inception of Darwin's theory of evolution by natural selection...
in 1842. There are at least two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
besides the nominate subspecies:
- Recherche Rock-wallaby Petrogale lateralis hacketti
- Pearson Island Rock-wallaby Petrogale lateralis pearsoni
A description published as Petrogale lateralis purpureicollis (Purple-necked Rock-wallaby) by Le Souef in 1924 is given in some listings, but this is now regarded as a distinct species. The specimens obtained at the Mcdonnell Ranges, and from the Western Kimberly, are also distinct enough to be separate subspecies of the Black-flanked Rock-wallaby. These populations, and the recognized subspecies, are distinguished by chromosomal
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
as well as morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
distinctions.
Endangered status
The subspecies found at the Recherche Archipelago was assessed as a vulnerable species
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
in 2006.
In South Australia, the Adelaide Advertiser reported on Monday October 1, 2007 that:
The race is on to save the black-flanked rock wallaby from extinction and captive breeding programs at Monarto Zoo and Adelaide Zoo are showing early promise.
The State Government claims there are just 50 animals left in the wild in South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
and the Advertiser article described the process of moving 15 wallabies to captivity in South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
, with known native locations to be at Pukatja / Ernabella in the Anangu Pitjantjatjara Yankunytjatjara or 'APY' Lands
Anangu Pitjantjatjara Yankunytjatjara
Anangu Pitjantjatjara Yankunytjatjara is a large Aboriginal local government area located in the remote north west of South Australia...
and also at New Well, some 300 km east of Adelaide.