BBC Inside Out searching for wallabies on the Isle of Man
Thousands of miles from their native Australia, Red-Necked Wallabies are roaming the Manx countryside in increasing numbers.
More than 100 are thought to be living in the north of the island after a pair escaped from the island's wildlife park half a century ago.
"They escaped the very first year the park opened," said manager Nick Pinder.
The wallabies are native to South East Australia and Tasmania but have adapted well to the island's cooler climate.
Duncan Bridges, director of the Manx Wildlife Trust said: "They graze on our grasslands, forage willow and young shrubs and fill the niche that is filled in the UK by small deer."
Red-necked Wallabies are most closely related to the kangaroos and wallaroos
"They seem to be becoming bolder and less afraid of humans. Just last year a group of wildlife spotters had wallabies sitting just metres away from them."
However, as the species has evolved since the 1960s, wildlife experts have noticed a worrying trend amongst some individuals.
"We've had several reports of blindness. That could be a result of inbreeding because of the small population here. We have not conducted any scientific testing to confirm this," continued Bridges.
The animals are not believed to be a threat to local creatures but wildlife experts continue to monitor their impact.
"One concern in the long term is that if the numbers get too high, then grazing could have adverse effects and they could out compete other species."
Sightings of wallabies have been reported all over Britain, all as the result of wildlife park escapes, but the colony found on the Isle of Man is by far the largest in the North Hemisphere.
Recently, BBC Presenter Jacey Normand travelled to the Isle of Man in search of the wallabies.
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