RebeccaWillers, from Shepreth Wildlife Park in Cambridgeshire, said charitable status was essential for the park to continue conservation and rescue work.
There are packs of escaped wallabies living wild in Buckinghamshire and Bedfordshire, but RebeccaWillers from Shepreth Wildlife Park said the animal was probably an escaped pet.
RebeccaWillers, curator of Shepreth Wildlife Park, said the charity had worked closely with countryside organisations, local colleges and the National Trust to find the best places for the animals to thrive.