杏吧原创

If you go down to the woods today, you might be in for a big surprise. There have been nearly 100 sightings of wallabies across Great Britain in the past decade.

鈥淓veryone was surprised by the number and the spread,鈥� says Holly English at University College Dublin in Ireland, who has detailed the sightings in .

It is possible that wallabies are breeding in the Chilterns of southern England and in Cornwall, south-west England. But most of the sightings are thought to be of animals that have escaped from zoos or private collections. 鈥淭hey are very good at escaping,鈥� says English.

The species in question is the red-necked wallaby, Notamacropus rufogriseus. This marsupial is native to south-eastern Australia including Tasmania, whose climate is similar to the UK鈥檚.

There has been a thriving population on the Isle of Man in the Irish Sea since the 1960s, now estimated to number . There is also a small population on Inchconnachan island in Loch Lomond, Scotland, originating from animals released by the island鈥檚 owner in the 1940s.

In England, a small population in the Peak District, thought to derive from animals released during the second world war, was long monitored by biologist Derek Yalden. It was reduced to a few individuals after being hit by big winter storms and finally died out in 2009.

鈥淭hen Yalden died in 2013 and the story of wallabies in the British countryside kind of got lost,鈥� says English. So she and Anthony Caravaggi at the University of South Wales have trawled through environmental records and media reports to between 2008 and 2018.

They only included sightings by multiple observers or where there is photographic evidence. They also didn鈥檛 count sightings of animals known to have been recaptured. 鈥淲e are quite confident in the ones we included,鈥� says English.

She urges people who spot a wallaby to report it to their or the UK鈥檚 . The NBN is also keen to record sightings of more mundane species, says English.

Red-necked wallabies have become an invasive pest in New Zealand. There is no reason to think those in the UK are a problem, but populations of introduced species can suddenly start to shoot up after persisting at low levels for a long time.