Re the Leeds stillwater that has recently been stocked with Arctic Charr...
Discussions reveal they provide some good winter sport for match and pleasure anglers.
They are bottom dwellers and prefer the deepest sections, choppy worm, bits of fish are the preferred baits.
When caught in matches February through March they are retained and transported back to holding ponds (somewhere?) along with the rainbows.
They are also to be found in Lake Windermere (they are a remnant of the last Ice Age). I was originally involved/interested and studied the decline of perch on Windermere, and so thought this might perhaps be of some interest too.
This lake is the largest natural freshwater lake in England, it is 12 miles long and about a mile wide, it has two basins joined by shallower water, the southern basin has recently suffered from eutrophication and the Charr invariably move to the upper basin and only return when conditions improve. The lake goes to a maximum depth of 64m and Charr were frequently caught commercially with gill-nets and long lines. "The Windermere Perch and Pike Project" at the outbreak of the Second World War:
Welcome to Aquatic Commons - Aquatic Commons
Apparently according to the freshwater biological association (data has been collected since the late 1930's) they do breed naturally in Windermere (generation times are typically 5-6 years).
There used to be 15 named species of Charr and now there is only one due to taxonomic reclassification. However more recent reviews suggest they should be split back up again for reclassification due to (salvelinus alpinus) variations of species complex "little mountain salmon"?
Interestingly they are not land locked but choose not go to sea like Scandinavian, Northern Norway, Canadian or Finland Charr, the salmon and sea trout migrate from Windermere via Morecambe bay and into the Irish sea, so there is nothing to physically stop them.
Scientific studies on Windermere reveal that 20-30 years ago would typically net about 10-20 Arctic Charr at a time in the breeding season compared to only 1 or 2 today. One possibility could be the increase in large pike that prey upon them in their spawning grounds each autumn, associated with some increase in the numbers of larger pike with the reduction in fishing effort.
Eutrophication of the South Basin in the 1970s and 1980s which may have affected the survival and recruitment of deep-water spring-spawning Charr in that basin.
Another cause could be temperature increases from global warming. Windermere has warmed up by 1 degree Celsius in recent years which doesn't seem much but it has been proposed could be the reason for there decline. If your an Arctic fish 1 degree is probably very significant.
BBC iPlayer - The Living World: Arctic charr
