The Northern Hopping-mouse is assessed as Endangered under criteria B1ab(i,ii,iii,v)+B2(ab(i,ii.iii,v). Its extent of occurrence (EOO) is 823 km², its AOO is 256 km²; it now occurs at a single location; and it is undergoing a continuing decline in habitat quality and probably also in AOO, EOO and number of mature individuals. 

It is also close to meeting criterion C: the estimation of population size has not previously been robust, but more recent information derived from intensive studies that assess burrow density and home range size indicates that the current population is approximately 2,400 individuals. It is undergoing continuing decline, at a rate of plausibly 20% in 5 years, but this is inferred and therefore not yet robust enough to meet the criterion. 

There is no robust estimate of extent of population decline, so criterion A cannot be applied, but current and future rates of decline are likely to be between 30 and 50%. It is now restricted to a single location and it is plausible that a single novel threat could rapidly dive the species towards extinction, so it also fits VU D2. 

The Northern Hopping-mouse is endemic to Australia where it is now known only from Groote Eylandt (2,285 km²) in the Northern Territory.

There has been an extensive program of surveys in recent years aimed at clarifying its distribution and status. Low level aerial helicopter survey transects (~4,800 km) targeting burrow clusters have covered broad areas of the Groote archipelago as well as targeting key habitats including sandy outwash areas adjacent to sandstone and coastal dune fields. Surveys in the north-eastern Northern Territory mainland and the Groote archipelago between 2014 and 2024 (Diete et al. 2016, Dixon and Barden 2019, Anindilyakwa Land and Sea Rangers ongoing assessments, P. Barden & K. Dixon unpublished data) have provided improved information on the distribution and status of the species. Surveys between 2017 and 2024 included revisiting ~90% of former mainland record locations (all but two) combined with ~1,900 km low level aerial helicopter transects searching for burrow clusters, including coastal dune habitats between Nhulunbuy and the Queensland border (Dixon and Barden 2019). Mainland surveys included ground surveys for burrows and camera trapping at previous record sites and other potential locations (Dixon and Barden 2019).

The type specimen was reportedly collected on the Cape York Peninsula, Queensland at some time prior to 1867. However, due to an absence of subsequent records, the provenance of this specimen was thought to be dubious (Winter and Allison 1980, Lee 1995, Woinarski and Flannery 2008). There are several recently discovered lines of evidence which now support the Cape York Peninsula collection locality. The specimen was acquired by the British Natural History Museum in a consignment with several other Cape York Peninsula endemic species (Barden 2022). Importantly, several previously unknown specimens of Northern Hopping-mouse have been recently discovered in museum collections that are likely to have come from Cape York Peninsula, including one with reasonably accurate collection locality details collected in the 1950s (Barden 2022).

There are also historical records of Northern Hopping-mouse from the Northern Territory mainland, with the most recent specimen being from the Cadell River in 1973. However, there have been no confirmed specimen records for 50 years from the Northern Territory mainland and for 70 years (Cape York Peninsula), with all recent records coming from Groote Eylandt (Diete et al. 2016, Dixon and Barden 2019, Barden 2022). Surveys were conducted in 2018-19 at all except two mainland Northern Territory sites where the species was previously stated to occur (Woinarski et al. 1999), and no evidence of presence was found (Dixon and Barden 2019). Based on mainland surveys conducted to date (Dixon and Barden 2019), it is considered more likely than not that the species is no longer present on the Australian mainland, and therefore likely to be restricted to Groote Eylandt.

Within the Groote Archipelago, surveys on all of the larger islands (Bickerton, Winchelsea, Connexion and the NE Island group) (Dixon and Barden 2019, P. Barden Anindilyakwa Land and Sea Rangers pers. comm. September 2024) using aerial burrow surveys using helicopters, ground transect searches for burrows, broadscale and targeted camera trapping) indicates that the species is not present on islands other than Groote Eylandt.

Surveys on Groote between 2012 and 2024 (greater than 120,000 camera trap nights across various projects, and other methods) indicate decline and local extinction at formerly occupied coastal dune areas. The species currently occupies limited specific habitats in the interior and eastern coast of the island (Paul Barden, Anindilyakwa Land and Sea Rangers, pers. comm., September 2024; P. Barden & K. Dixon, unpublished data). A comparison of recent surveys with data collected between 1990 and 2010 indicate ongoing declines on Groote Eylandt, with populations identified during earlier assessments no longer present on the south-east coast, some areas of the southern interior along the Kings Crossing road, the Umbakumba area and northern Makbamanja Peninsula. Remaining populations occupy restricted areas (in the central western interior of Groote Eylandt and with a second disjunct range area on the eastern coast of the island (Paul Barden, Anindilyakwa Land and Sea Rangers, pers. comm., September 2024; P. Barden and K. Dixon, unpublished data).   

There are no reliable estimates of density or population size prior to 2014. Some early surveys using burrow densities were conducted before the potential for misidentification with burrows of other rodent species was fully understood (Diete et al. 2014, 2015), suggesting that old estimates using this technique are unreliable. Barden (2017) and Diete et al. (2016) estimated a population of 2,000 individuals based on the distribution of confirmed burrows and occupied areas with reference to radio tracking range polygons. Long term monitoring sites on Groote Eylandt (2020-2024) indicate approximately 0.8 burrows per hectare at key sites. Based on a maximum individual range polygon of 24 hectares (Diete et al. 2016), burrow data from extensive recent surveys indicates an occupation area of 3,050 hectares on Groote Eylandt. Allowing for a best-case scenario of 1-1.5 adults per burrow and assuming that all areas detected in the past decade remain occupied, a reasonable population estimate would be 2,440-3,660 breeding individuals. Actual numbers are likely to be considerably less than this in 2024, as there have been documented declines in numbers of active burrows at monitored sites between 2019 and 2024 and some sites have been found to support lower burrow densities. There have also been several catastrophic events that have impacted greater than 90% of Northern Hopping-mouse sites since 2022, including extensive hot fires in the 2022 mid to late dry season and extensive flooding, rainfall and extreme weather associated with a cyclone in early 2024.

The species appears to have declined significantly in some areas, particularly coastal areas of Groote Eylandt, as intensive trapping and extensive searches for signs from 2012-2014 were only able to confirm the presence of the species in one coastal location in the south-east section of the island (Diete et al. 2016). Subsequent surveys using aerial helicopter burrow surveys, camera trapping and ground inspections have been conducted at all coastal areas on Groote Eylandt by the Anindilyakwa Land and Sea Rangers and Territory Natural Resource Management. These surveys only detected this species from five discrete and restricted coastal sites on eastern Groote Eylandt (Dixon and Barden 2019, P. Bardon & K. Dixon unpublished data). 

The Northern Hopping-mouse occurs in a range of vegetation types on sandy substrates (Woinarski et al. 2014, Diete et al. 2016). It is patchily distributed. It was previously thought to be most abundant in dunes and sand sheets, supporting coastal heathlands, shrublands, and tussock grasses (Woinarski et al. 1999, Woinarski and Flannery 2008) but recent work has found it more abundant in Eucalypt open forest and woodlands, particularly fringing sandstone plateaus (Diete et al. 2016). Coastal subpopulations have been detected in quaternary dune fields away from the coast. All confirmed populations are within ~700 m of the high tide line and inland populations are generally found on areas of alluvial sandy outwash within 700 m of sandstone margins (P. Barden Anindilyakwa Land and Sea Rangers pers comm. September 2024).

This species is difficult to trap in traditional aluminium box and wire cage traps (Woinarski 2005) but can be captured in deep pitfall traps (Diete et al. 2016).

The gestation period is about seven weeks, and the females usually give birth to three young (Dixon and Huxley 1985, Diete et al. 2016).

Feral cats, strip-mining (mainly manganese on Groote Eylandt but also bauxite in north-eastern Arnhem Land and Cape York Peninsula), and changes in fire regimes are threats, and these threats are probably compounding (Woinarski et al. 2014). Based on data held by the Anindilyakwa IPA, 10-20% of the currently known Groote Eylandt distribution is in close proximity (less than 500 m) or within active or granted mining and mining infrastructure areas proposed for mining in the next 5 to 10 years. All other remaining Northern Hopping-mouse areas on Groote Eylandt are covered by granted or under application mineral extraction licences. Northern Hopping-mouse populations are potentially at risk from mining due to direct clearing impacts and edge effects including dust, changes in vegetation cover, vegetation dieback due to dewatering or flooding, noise, light, vehicle movements, blast vibration, changes in hydrology and fire, and increased access for feral cats (Felis catus) (and increased density of cats in and around disturbed areas). Hard rock quarrying for road and other construction also presents a risk, as Northern Hopping-mouse populations often occur adjacent to preferred hard rock resource areas. The species appears to tolerate small scale, patchy burns; however, hot, large-scale fires are likely detrimental (Diete et al. 2016). Habitat degradation and structural changes to vegetation by introduced herbivores, combined with feral cats and altered fire regimes may have contributed to its decline and possible extirpation on the mainland (Dixon and Barden 2019).

Feral cats are present on Groote Eylandt, but their impact on Northern Hopping-mouse is currently poorly resolved.

Groote Eylandt is managed as an Indigenous Protected Area, although large components of the IPA are subject to active ongoing mining and all other areas are covered by granted or under application mineral licences. There is ongoing research in the Groote archipelago investigating Northern Hopping-mouse distribution, population and trends, conservation genetics, general and fire ecology and survey methods (collaborative project with the Anindilyakwa Land Council, Territory Natural Resource Management, Anindilyakwa Land and Sea Rangers and Charles Darwin University) with funding from the Commonwealth Government until June 2026.

There is little amelioration of main threats. On Groote Eylandt, mining infrastructure development is expanding into areas that are occupied by or adjacent to Northern Hopping-mouse populations as a precursor to active mining at these locations. 

There is a Groote Archipelago Threatened Species Management Plan 2019-2028. 

The Northern Hopping-mouse is listed as Endangered under Australian national environmental legislation, and a Conservation Advice (TSSC 2021) provides general conservation guidelines. The Northern Hopping-mouse was listed as a ‘priority species’ in the Australian government’s Threatened Species Action Plan 2022-2032.