Now you see them, now you don't. Perhaps it's one of the more fascinating aspects of the wildlife around us. Ten or 20 years ago the mink scare was going strong, certainly in this part of the country. This, as everyone knows, involved escapees from mink farms that had closed. On one tributary of the Boyne, where otters had a well-established history, the mink appeared to everyone's dismay. A friend acquired a mink trap. No mink took the offered bait. Then they were seldom seen. One man thinks (hopes) that he obliterated one entire family when he saw them troop into a bunch of reeds just five yards or so across on the other bank from him. He fired his shotgun. Not a stir. Not a squeak. The river was running high then, and he couldn't easily cross. And other sightings have not been made from his area.
There is a thought that some have moved westward. Unfortunately, the river has lost its otters. Perhaps they too have simply moved. And there was a report from a visitor to the house who saw one on their old hunting-ground nearby. On one else has seen him or her. But then it goes so all the time - the sparrow is rare in Dublin. "We have lost ours entirely," says one south Dublin resident. A man on Dublin bay says that he has a healthy and lively sparrow population.
Anyway, these thoughts spring from an article in the BBC Wildlife magazine for July. It tells that the mink are undergoing "a spectacular decline" in numbers over seven years. It says that for long the mink did huge damage to ground-nesting birds like coots and moorhens and terns. (What about wild duck?) Now the decline of the mink is described by one of the writers of a report on the situation as "astonishingly high". And all because of the otter, about which there has been much worrying. In the west (Wales) the mink has declined with a 91 per cent drop in the number of occupied sites. And the otter, about which there was much gloom across the water a few years ago, has been rising in numbers.
Since 1977 in Britain, the otter has doubled in numbers every seven years. There is, indeed, evidence, this article states, that otters kill and eat mink and that they destroy the sites used by mink to mark their territories. Scientists now believe that mink could only colonise Britain so quickly because of the low numbers of otters at that time, attributed here to the widespread use of organochlorine pesticides in agriculture. Mink and otter, the conclusion is, will stabilise with fewer mink than when otters were rare, but with higher density than at present in many areas. How about us?