Ampurta
Introduction
The ampurta, scientifically known as Dasycercus hillieri, is a small to medium-sized carnivorous marsupial native to Australia. Recently recognized as a distinct species after a lengthy period of synonymy with D. cristicauda, the ampurta belongs to the Dasyuridae family, which also includes other notable Australian marsupials such as quolls, dunnarts, numbats, the endangered Tasmanian devil, and the extinct thylacine. The ampurta’s unique characteristics and conservation status make it an important subject of study in the field of Australian wildlife biology.
Description
The ampurta exhibits a sandy-colored fur on its upper body that transitions to a darker grey on its underparts and inner limbs. This coloration helps it blend into its arid environment. There is a notable sexual dimorphism within the species; adult males typically weigh between 100 to 185 grams (3.5 to 6.5 ounces), while females range from 65 to 120 grams (2.3 to 4.2 ounces). The head-to-body length of the ampurta varies from 125 to 230 millimeters, and its tail measures between 75 and 125 millimeters in length.
Identifying the crest-tailed mulgara in the wild can be challenging as it is often confused with the closely related brush-tailed mulgara (D. blythi). One of the key distinguishing features is the tail morphology; the crest-tailed mulgara possesses a distinctive crest of fine black hairs along the dorsal edge of its tail, creating a fin-like appearance, while the brush-tailed mulgara does not exhibit this trait. Additionally, female crest-tailed mulgaras typically have eight nipples compared to six in their brush-tailed counterparts.
Taxonomy
The taxonomic history of the genus Dasycercus is marked by confusion and reclassification. Originally described by Peters in 1875, several forms of carnivorous marsupials were assigned to this genus over time. Chaetocercus cristicauda was first described by Kreft in 1867, followed by Phascogale blythi by Waite in 1904 and Phascogale hillieri by Thomas in 1905. By 1970, William Ride’s work suggested these forms were synonymous with Dasycercus cristicauda.
Further taxonomic revisions occurred when Woolley proposed two subspecies in 1995, which were confirmed to represent two distinct species through mitochondrial gene sequencing in 2000. In subsequent years, additional species including southern mulgara (D. archeri), little mulgara (D. marlowi), and northern mulgara (D. woolleyae) were described. These advancements led to the resurrection of Dasycercus hillieri for extant populations of crest-tailed mulgara.
Distribution
The distribution of the crest-tailed mulgara has changed significantly over time due to various environmental factors and human activities. Historically, its range included vast areas across arid Australia, such as Ooldea on the Nullarbor Plain and regions around South Australia and Queensland. Owl pellet examinations have indicated its presence in various locations including Flinders Ranges and Mutawintji National Park.
Recent genetic analyses suggest that the species is now primarily restricted to central eastern deserts within Australia, particularly in regions like the Simpson-Strzelecki Dunefield bioregion. The brush-tailed mulgara has displayed a broader distribution from Queensland to near-coastal Western Australia.
Ecology and Habitat
Habitat
The habitat preferences of the crest-tailed mulgara are specific, favoring crests and slopes of sand ridges or areas around salt lakes in inland Australia. During daylight hours, these marsupials seek refuge in burrows located at the base of vegetation like sandhill canegrass or Nitre bush surrounding salt lakes. Factors such as rainfall patterns, food availability, and fire history influence their habitat selection.
Diet
The diet of the crest-tailed mulgara is opportunistic, comprising a variety of insects, arachnids, rodents, reptiles, centipedes, and small marsupials. This dietary flexibility allows them to forage effectively across dune crests and their surrounding environments.
Breeding and Reproduction
Crest-tailed mulgaras reach sexual maturity within their first year. Breeding occurs between winter and early summer, during which females can raise up to eight young per litter. The young become independent during spring and early summer months.
Conservation Status
The conservation status of the crest-tailed mulgara has fluctuated over time due to changing environmental conditions and population dynamics. Initially classified as Endangered in the early 1900s, populations saw a resurgence in recent years; by 2019 it was classified as Least Concern with a significant expansion of its range documented between 2015 and 2021.
This recovery has been largely attributed to a decline in feral cat populations following successful management strategies targeting non-native rabbit populations—rabbits being a primary food source for feral cats. Additionally, this marsupial’s ability to enter a torpid state during extreme drought conditions enhances its survival rates during adverse environmental events.
Threats
Despite its recent population growth, the crest-tailed mulgara remains vulnerable to several threats that can impact its survival and habitat integrity. Predation from European red foxes and feral cats poses significant risks, alongside habitat degradation caused by livestock grazing and changes in fire regimes due to land management practices.
Interestingly, after the introduction of rabbit hemorrhagic disease virus (RHDV), there was a dramatic increase in both the extent of occurrence and area occupancy for this species—indicating how interconnected species dynamics can influence population viability.
Conclusion
The ampurta (Dasycercus hillieri) stands as an important example of Australia’s unique biodiversity and ecological challenges. As research continues to clarify its taxonomy and distribution while conservation efforts adapt to ongoing threats, it becomes imperative for wildlife management strategies to consider both historical data and contemporary ecological dynamics. Protecting this remarkable marsupial not only aids in preserving an integral part of Australia’s natural heritage but also contributes to broader efforts aimed at conserving vulnerable species throughout the continent.
Artykuł sporządzony na podstawie: Wikipedia (EN).