Besides being known for their cube-shaped droppings, wombats are unfortunately also subject to the disease sarcoptic mange. In order to better understand how the mange-causing mites are able to spread between wombats, scientists have developed a burrow-exploring robot.
Wombats are primarily nocturnal animals, spending the daylight hours sleeping in burrows that they dig in the ground. They change burrows every four to 10 days, often simply moving into a different burrow that was previously dug and occupied by another wombat. It is believed that the parasitic Sarcoptes scabiei mites, which cause sarcoptic mange, may be transferred between wombats when they swap burrows in this fashion.
Researchers from Australia's La Trobe University and University of Tasmania wanted to see how likely this was to be the case, so they developed the new robot. Known as the WomBot, the battery-powered device is 30 cm long (11.8 in), weighs 2 kg (4.4 lb) and moves on tank-like treads at a top speed of 0.15 meters per second (0.5 ft/s).
It's also equipped with temperature and humidity sensors, along with front and rear cameras and LED lights. Live video from those cameras is relayed via an attached Ethernet cable to a human operator up top. Additionally, a gripper on the front of the robot allows data-logging sensors to be placed inside burrows and subsequently retrieved.
"Wombat burrows are challenging to study as they are narrow, muddy, can be dozens of meters long and contain steep sections and sharp turns," says La Trobe's Dr. Robert Ross, corresponding author of a paper on the study. "WomBot allows us to enter and explore these burrows without destroying them or using expensive ground-penetrating radar. This can help us better understand the environmental conditions within burrows that may facilitate sarcoptic mange transmission."
In September of 2020, the robot was used to explore 30 wombat burrows in Tasmania. It was found that the average temperature inside those burrows was 15 ºC (59 ºF), while the average relative humidity was 85 percent. According to previous studies, the mites thrive at around 10 ºC (50 ºF) and a relative humidity of 75 to 95 percent – conditions similar to those within the burrows.
Based on this data, the scientists now believe that female Sarcoptes scabiei mites could survive for nine to 10 days at the entrance of a burrow – or 16 to 18 days inside of it – spreading from one wombat occupant to the next.
"Our findings indicate that the environmental conditions within wombat burrows may facilitate sarcoptic mange transmission by promoting mite survival," says Ross. "WomBot could potentially be used to help reduce the spread of sarcoptic mange by delivering insecticide or ensuring burrows are empty before being temporarily heated in order to eradicate mites."
And in case you're wondering, he tells us that the robot only encountered one wombat within its burrow. The animal was presumably sleeping, and the team quickly backed the WomBot away from it.
The paper was recently published in the journal SN Applied Sciences.
Source: Springer