A wombat excavates shelter for its own use. In doing so, it creates a tunnel, entrance, soil mound and network of nearby paths that other animals can use too. Its influence extends beyond the patch of ground occupied by its body.
Ecologists call an animal an ecosystem engineer when its physical changes to the environment alter resources available to other organisms. Wombat burrows make that idea tangible. Shelter below ground, food opportunities at the entrance and changed vegetation around the mound can serve different visitors.
Start with the wombat’s own home
The Bare-nosed Wombat, Vombatus ursinus, is also known as the Common Wombat. NSW Environment and Heritage describes its use of temperate forests, grassy feeding areas and diggable ground, often on slopes above creeks and gullies.
Burrows provide shelter from heat and predators. Some extend many metres and have several entrances. A wombat can use more than one burrow, while overlapping home ranges can result in different wombats using the same one. This is more complicated than assigning every hole to one permanently resident animal.
The site also serves an animal with its own needs. Young may remain dependent after leaving the pouch, and a burrow can be occupied when no adult is visible outside. Quiet ground at a particular hour tells us little about the full pattern of use.
These observations concern the Bare-nosed species. Australia’s hairy-nosed wombats inhabit different landscapes, so evidence about their burrows needs its own species and place attached.
Underground conditions buffer the weather
An entrance exposed to the day’s weather and a chamber farther underground have different surroundings. The useful property of a burrow is often the reduction in fluctuations, rather than a promise that every tunnel stays at one ideal temperature.
In a 2021 study at Cape Portland, Tasmania, Elizabeth Browne and colleagues measured temperature and humidity inside Bare-nosed Wombat burrows and compared conditions with those outside. Their winter comparison found much steadier conditions within burrows across the daily cycle.
The researchers were investigating the environment available to the mite that causes sarcoptic mange. That context matters: a sheltered microclimate has ecological effects beyond comfort, and sharing space can also create routes for indirect disease transmission. Shelter is one resource within a living system, rather than a guarantee of safety from every hazard.
The measurements do not give a universal temperature for Australian wombat burrows. Season, site and position within a tunnel matter. Nor do temperature records alone show how every visiting reptile or mammal uses the available conditions.
A visitor may shelter, forage or hunt
Julie Old, Nicole Hunter and Jack Wolfenden’s 2018 study used cameras to document animals using Bare-nosed Wombat burrows. Their records included entry for shelter and hunting, and use of the entrance and excavated soil for foraging.
Those are different relationships. A small mammal taking refuge and a predator searching the entrance can both be associated with a burrow. A visit does not mean that both animals receive the same benefit, or that they occupy the tunnel together.
The study recorded introduced animals, including foxes, cats and rabbits, as well as native wildlife. A structure can be useful habitat without being used exclusively by native species. Describing every visitor as a welcome housemate would obscure those interactions.
A camera view also has a boundary. An animal investigating the opening has not necessarily entered it. A short entry does not establish where it went or how long it stayed. These distinctions help turn an appealing image into an accurate behavioural record.
A different wombat, a different community
Research on Southern Hairy-nosed Wombats, Lasiorhinus latifrons, provides an important comparison. Elizabeth Thornett, Bertram Ostendorf and David Taggart monitored burrows on South Australia’s Wedge Island using 34 cameras between March and September 2015.
Among the animals repeatedly using burrows were Black-footed Rock-wallabies, Brush-tailed Bettongs, reptiles and Little Penguins. That is a strikingly different community from one around a forest burrow in south-eastern NSW.
The island result demonstrates co-use in that setting. It does not predict that a mainland wombat burrow will contain the same species, or show that every visitor uses the burrow continuously. The important connection is the resource made available by digging; the users depend on the surrounding fauna and landscape.
What the post-fire cameras actually measured
In a 2024 study, Grant Linley and colleagues compared 28 Bare-nosed Wombat burrows with paired sites lacking burrows near Albury, NSW. Cameras operated from June 2021 to April 2022, starting about 16 months after the 2019–20 fires.
Some smaller animals, including Bush Rats, Agile Antechinus and Lace Monitors, were more active at burrows. Some larger mammals were more active at comparison sites. Of 31 species recorded interacting with burrows, ten were recorded entering or emerging; investigation of the entrance was much more widespread. Animals also used water that temporarily pooled in some burrows.
The findings support a role for burrows in a recovering landscape. These cameras did not observe the fires themselves, test whether wombats deliberately guided other animals, or establish that every animal entering a burrow survived a fire. The purposeful rescue story goes beyond the experiment. Its evidence concerns animals’ measured use of an existing habitat feature after disturbance.
The mound changes habitat above ground too
The tunnel is only one part of the engineering. Soil brought to the surface and repeated paths can change the pattern of ground conditions around a burrow.
Thomas Guy and Jamie Kirkpatrick’s study of alpine Tasmania compared wombat mounds, paths, dung sites and undisturbed ground. They found altered topography and vegetation, including greater herb cover associated with disturbed places. Burrow mounds, often also used as dung sites, had higher nitrogen than the comparison ground.
Other measurements did not all change in the same way: the study found no difference in soil bulk density, pH or phosphorus among mounds, paths and undisturbed areas. “Wombats improve every aspect of soil” would therefore overstate the result.
The more useful picture is a mosaic. Digging, walking, grazing and depositing dung create different patches, with effects shaped by that alpine environment. Those patches can matter to plants and animals even where they occupy only part of a landscape.
Keep the entrance usable and observation light
Observe from an existing safe route without sitting across an entrance or following a wombat inside. NRE Tasmania specifically warns against pursuing wombats into burrows. Do not reach into a tunnel or put a camera inside to find its users.
Leave openings, excavated soil and nearby shelter intact. A household conflict near a building or fence needs advice from the relevant wildlife authority and suitably qualified people, rather than improvised blocking, digging or eviction. Burrow rules and management conditions vary by jurisdiction.
For an injured or unwell wombat, use the rescue directory and describe what you have observed without handling or treating it. For an ordinary burrow, note the broad habitat and the behaviour already visible. A brief record can distinguish passing, investigating and entering while leaving the habitat available for its next user.