Dusky hopping mouse
Template:Short description Template:Speciesbox The dusky hopping mouse (Notomys fuscus), is a small rodent endemic to Australia, inhabiting desert regions characterised by sand dunes. Populations have experienced significant declines since the arrival of Europeans, and continue to be subject to threatening processes. It is currently listed as a threatened species.<ref name=":0">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
TaxonomyEdit
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The dusky hopping mouse, or Wilkinti,<ref name=":0" /><ref name=":1">Template:Cite book</ref> is a mammal in the order Rodentia, and suborder Sciurognathi. The species is in the family Muridae and the subfamily Murinae (includes all Australian native rats and mice). The dusky hopping mouse belongs to the genus Notomys, a group of desert-dwelling rodents.<ref name=":2">Template:Cite book</ref>
The species was originally described as Ascopharynx fuscus (Wood Jones 1925) from a specimen collected in South Australia. Subsequent collections were described as Notomys fuscus eyreius in 1960.<ref>Template:Cite book</ref> Hopping mice collected in Queensland between 1957 and 1959 were described as a new species, Notomys filmeri, however, later taxonomic investigation revealed these were Notomys fuscus.<ref name=":4">Template:Cite journal</ref>
DescriptionEdit
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The dusky hopping mouse has pale orange-brown upper parts, occasionally with grey tinged streaks. The under parts are grey-white.<ref name=":6">Template:Cite book</ref> It grows to 80–115 mm long,<ref name=":6" /> with an average weight of 35 g.<ref name=":2" /><ref name=":6" /> The tail is between 120 and 155 mm long,<ref name=":6" /> ending in a tuft of dark hairs.<ref name=":0" /><ref name=":7">Template:Cite book</ref> They have a well-developed throat pouch, with an opening surrounded by a fleshy margin with inward pointing, coarse white hairs.<ref name=":6" /><ref name=":8">Template:Cite journal</ref> Its ears are large and furless for dissipating heat, and they have prominent dark eyes,<ref name=":0" /><ref name=":9">Template:Cite journal</ref> and strong incisor teeth.<ref name=":7" /><ref name=":9" /> It has short front legs, and long, elongated hind feet.<ref name=":0" /><ref name=":7" /> with only three pads on the sole.<ref name=":6" /> Male reproductive anatomy is distinctive.<ref name=":2" /> The glans is small and tapered towards the tip. The surface has large dorsally projecting spines, with slightly curved tips.<ref>Template:Cite journal</ref> The testes are extremely small compared to other native rodents.<ref name=":11">Template:Cite journal</ref><ref name=":12">Template:Cite journal</ref> Females have two pairs of inguinal teats.<ref name=":6" /><ref name=":7" />
DistributionEdit
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The species historically inhabited large areas of central Australia, south-west Queensland, and far west South Australia,<ref name=":10">Template:Cite journal</ref> and Western Australia.<ref name=":13">Template:Cite journal</ref> Sub-fossil specimens were found in far-south South Australia, near the Flinders Ranges.<ref name=":10" /> Populations were recorded in the Northern Territory, however have not been observed since 1939.<ref name=":15">Template:Cite journal</ref><ref name=":16">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> It is highly likely to have occurred in western New South Wales.<ref name=":14">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Distribution has shown a marked decline of more than 90% since the arrival of Europeans,<ref name=":10" /> with populations now patchy and highly fragmented.<ref name=":0" /><ref name=":10" /> It is currently thought to be restricted to the Cobblers Sandhills and Strzelecki Desert in north-east South Australia,<ref name=":10" /><ref name=":13" /> south-west Queensland and far north-west New South Wales.<ref name=":6" /><ref name=":18">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The species was presumed to be extinct in New South Wales, before being re-discovered in Sturt National Park in 2003.<ref name=":14" /><ref name=":19">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Since then, a number of sightings have been recorded near Broken Hill, New South Wales.<ref name=":19" /><ref name=":20">Template:Cite journal</ref>
EcologyEdit
HabitatEdit
The preferred habitat of the dusky hopping mouse is the crests and slopes of stabilised desert sand dunes and ridges,<ref name=":13" /><ref name=":19" /> with sand required for digging burrows.<ref name=":17">Template:Cite iucn</ref> Dense populations tend to occur only within the vicinity of major drainage systems.<ref name=":10" /> It does not appear to favour a particular vegetation type, occurring in dunes well-vegetated by canegrass (Zygochloa paradoxa), as well as degraded ecosystems dominated by ephemeral herbaceous species.<ref name=":10" /> It has also been associated with perennial shrub species such as nitre bush (Nitraria billardierei) and Acacia species.<ref name=":19" />
BehaviourEdit
The dusky hopping mouse is a social species,<ref name=":6" /> living in colonies of up to five individuals.<ref name=":19" /><ref name=":17" /><ref name=":0" /> They live in burrows consisting of vertical shafts with a series of entrances approximately 3 cm in diameter,<ref name=":6" /><ref name=":0" /> leading to a network of horizontal tunnels and chambers<ref name=":1" /><ref name=":2" /> extending up to 2m deep.<ref name=":17" /> Notomys species dig their burrows from below, resulting in an absence of loose sand surrounding the entrance holes.<ref name=":9" /> This species prefers to forage at night in sheltered microhabitats, rather than open areas, to avoid the risk of predation.<ref name=":22">Template:Cite journal</ref> It is an opportunistic,<ref name=":10" /> omnivorous feeder, however is considered a granivore (74% of the diet).<ref name=":21">Template:Cite journal</ref> Green plant material, insects,<ref name=":21" /> and fruits are also eaten.<ref name=":10" /> It does not need to drink water.<ref name=":0" /><ref name=":19" /> The neck throat pouch is a glandular area, used for marking territories. Females may scent-mark their young, ensuring they acquire a smell that grants them acceptance within the colony.<ref name=":8" />
Life cycle and reproductionEdit
In the wild, lifespan has been recorded as being up to 13 months of age.<ref name=":17" /> In captivity, males and females reach reproductive maturity at 70 days of age.<ref name=":23">Template:Cite journal</ref> This species is likely monogamous, and females may display selectivity in choosing which males will sire offspring.<ref name=":9" /><ref name=":12" /> Breeding is non-seasonal, occurring year-round, in both wet and dry conditions.<ref name=":10" /><ref name=":23" /> Females are observed to be polyoestrous, with a gestation period of 32 to 38 days, and a litter size of one to five offspring. An average of 42 days occurs between litters, and the maximum reproductive life for females is approximately 24 months, and males 36 months.<ref name=":23" /> Subpopulations may persist at low but stable numbers, however others exhibit “boom-and-bust” variation, with numbers increasing and decreasing rapidly in response to rainfall and resource availability.<ref name=":20" /><ref name=":17" /><ref name=":24">Template:Cite journal</ref><ref>Template:Cite journal</ref>
Dispersal and movementEdit
When travelling slowly, hopping mice move on all fours, however they hop on the hind feet when travelling at speed.<ref name=":2" /><ref name=":7" /> Individuals can disperse over large distances to colonise isolated habitats, crossing areas of hard unsuitable substrate.<ref name=":17" /> Foraging distances are up to 400m per night, extending up to 1.5 km over three nights.<ref name=":17" /><ref name=":24" /> Individuals inhabiting degraded habitats with limited vegetation and food resources show lower mobility, whereas those inhabiting highly diverse habitats with a wide variety of resources have wider ranging movement patterns.<ref name=":24" />
ThreatsEdit
PredationEdit
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Introduced predators such as the red fox (Vulpes vulpes)<ref name=":30">Template:Cite journal</ref> and feral cat (Felis catus) have detrimental impacts on dusky hopping mouse populations.<ref name=":22" /><ref name=":25">Template:Cite journal</ref> Where cat and fox abundance is high, dusky hopping mouse populations decline.<ref name=":30" /><ref name=":25" /><ref name=":31">Template:Cite journal</ref> Cats target smaller prey such as rodents, which can make up a large proportion of their diet.<ref name=":32">Template:Cite journal</ref> Native species, such as the barn owl (Tyto alba), frequently consume this species,<ref name=":22" /><ref name=":26">Template:Cite journal</ref> as does the dingo.<ref name=":22" /><ref name=":28">Template:Cite journal</ref> Dingoes may de-populate localised populations of hopping mice within months,<ref name=":27">Template:Cite journal</ref> particularly under drought conditions.<ref name=":28" /> Crest-tailed mulgara (Dasycercus cristicauda) have also been recorded eating this species.<ref name=":29">Template:Cite journal</ref>
Habitat degradationEdit
Livestock, kangaroos and rabbits overgraze vegetation required for shelter and food sources,<ref name=":19" /> leading to scalding, wind and sheet erosion and a shift from perennial, to less productive ephemeral plant species.<ref name=":10" /><ref name=":24" /> Livestock also damage habitats by trampling.<ref name=":32" /><ref name=":33">Template:Cite journal</ref> Reduced food availability limits hopping mice abundance, and the availability of suitable habitat limits their distribution.<ref name=":10" /><ref name=":24" /> However, higher annual rainfall and more productive ecosystems may buffer the effects of livestock, by providing more dependable and abundant resources, allowing mice to proliferate.<ref name=":10" /><ref name=":28" />
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CompetitionEdit
Competition for food and habitat occurs with the house mouse (Mus musculus),<ref name=":17" /> which increase in abundance more rapidly under favourable conditions, depleting resources and outcompeting the native mice.<ref name=":10" /> The rabbit (Oryctolagus cuniculus) also competes with dusky hopping mice for food. Declines in rabbit abundance, and increased resources, following the release of the Rabbit Haemorrhagic Disease Virus (RHDV) in Australia in 1995, saw the dusky hopping mouse increased their extent of occurrence by 241 to 365% over 14 years.<ref name=":34">Template:Cite journal</ref>
Climate ChangeEdit
This species experiences natural population declines during dry periods, when food resources are limited, and increase strongly following rainfall events.<ref name=":24" /><ref name=":28" /> Decreases in rainfall, less frequent rainfall events and more frequent droughts under climate change may cause declines or extinctions.<ref name=":18" /><ref name=":17" /> Predation of hopping mice by dingoes intensifies under drought conditions, which may significantly impact populations.<ref name=":28" />
Conservation statusEdit
The total remaining population is estimated to be between 2,500 and 10,000 individuals.<ref name=":0" /><ref name=":10" />
- International Union for the Conservation of Nature (IUCN) Red List: Vulnerable<ref name=":17" />
- Australia: Vulnerable (Environment Protection and Biodiversity Conservation Act 1999)<ref name=":0" /><ref name=":18" />
- New South Wales: Endangered (Biodiversity Conservation Act 2016 No 63)<ref>{{#invoke:citation/CS1|citation
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- South Australia: Vulnerable (National Parks and Wildlife Act 1972)<ref>{{#invoke:citation/CS1|citation
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- Queensland: Endangered (Nature Conservation Act 1992)<ref name=":5">{{#invoke:citation/CS1|citation
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- Northern Territory: Endangered (Territory Parks and Wildlife Conservation Act 2000)<ref name=":16" /><ref>{{#invoke:citation/CS1|citation
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