SIR - Angler Michael Heylin is wrong when he states that fur farmers did not release the vast majority of mink now living in the wild (T&A Letters, September 6).

There was a boom in fur farming in the 1940s, with many ex-servicemen using their demob payments to open small-scale farms incarcerating mink in tiny wire cages. They were subsequently killed by gassing or by electric shocks and skinned for their coats.

When, in the 1950s, bigger operators became dominant, a great many of these smaller businesses went broke and it was then that they opened their cages and released the mink. The numbers of mink in the wild already amounted to scores of thousands by the time limited releases were undertaken by animal rights people starting in the 1990s.

As far as mink having no natural predator, that is also misleading. BBC Wildlife magazine reported in 2000 an astonishingly high decline' in mink populations in the preceding seven years due to the flourishing of otters.

There is evidence,' the magazine reported, that otters kill and eat mink and that they destroy the sites used by mink to mark their territories.' Andrew Tyler, Director, Animal Aid, Bradford Street, Tonbridge, Kent