In birds, which are an efficient [[bioindicator]], species diversity decreases 50 percent in radioactively contaminated areas compared to clean areas, while abundance decreases by two thirds. There have been reports that wildlife has flourished due to significant reduction of human impact.<ref>[http://news.bbc.co.uk/2/hi/europe/4923342.stm ''Wildlife defies Chernobyl radiation''], by Stefen Mulvey, BBC News</ref> For this reason, the zone is considered by some as a classic example of an [[involuntary park]]. Some claim that the populations of traditional [[Polesia]]n animals (like [[Gray Wolf|wolves]], [[Badger]], [[wild boar]], [[Roe Deer]], [[White-tailed Eagle]], [[Black Stork]]), [[Western Marsh-harrier]], [[Short-eared Owl]], [[Red Deer|red deer]], [[moose]], [[Great Egret]], [[Whooper Swan]], [[least weasel]], [[Common Kestrel]] and [[beaver]]) have multiplied enormously and begun expanding outside the zone. These claims, however, are not substantiated by any systematic census of any animal [[taxon]]. <ref>
