It is a myth that wolves regulated fox numbers and that, with the loss of wolves, fox numbers increased. The best data on the impact of wolves on foxes comes from Isle Royale, a large island in Lake Superior, where wolf and fox numbers have been monitored for fifty years. Wolves do not reduce fox numbers, and in fact foxes benefit from scavenging on wolf kills. Wolves disappeared from England many centuries ago, but fox numbers remained low, so much so that large numbers had to be brought over from Europe in the 1800s to ensure an adequate supply of foxes for hunting. So there is no truth in the story that wolves regulated fox numbers in Britain and that, in the absence of wolves, they need to be killed to reduce numbers. -
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