It's Always More Complicated

Because these came up in several conversations my sojourn in Minneapolis, further details.

From Wikipedia on Wallabies

A number of wallaby breeding colonies in other parts of the world have been established at times in the past, but only one proved viable. The two principal populations were those of the island of Inchconnachan in Loch Lomond, Scotland and in the Peak District of England. The Peak District population was established in around 1940 by five escapees from a local zoo and lasted until at least 1993. At its peak the population numbered around fifty individuals. The Loch Lomond population was deliberately established in 1975 and unmanaged has achieved a viable population of around 28. Restricted to the island of Inchconnachan there are occasional escapes to the mainland when the loch freezes over. Other populations in the United Kingdom that for some periods bred successfully included one near Teignmouth, Devon, another in the Ashdown Forest, East Sussex and one on the island of Bute and Lundy.

There is also a small population on Lambay Island off the east coast of Ireland. This group was introduced by Dublin Zoo after a sudden population explosion in the mid 1980s.

Other sources suggest that the Peak District wallabies may still be around but retired to more remote areas. There have been unconfirmed sightings since the mid-90s.