A comparison was made between the average enclosure size of a random sample of mammals lept during the years 2000-2001in a random sample of UK zoological collections and the minimum home range of these taxa in the wild. Allometric laws were used to estimate the home range area, while direct observation from videotaped visits to the collections was used to estimate enclosure size area. The results showed that, as an average, the average enclosure size had an area 100 times