Fears for rare UK lake fish species

[goosey]

Poor water quality, the silting-up of spawning grounds and competition from other species is being blamed for the demise of a rare species of fish in Bassenthwaite (a lake in the Lake District in England). Scientists are worried that one of the UK's rarest fish, the "Vendace" may no longer be inhabiting the lake! Populations of the species vendace have recently been found in Derwentwater, but night filming has failed to find evidence of the fish in Bassenthwaite. The Bassenthwaite Lake Restoration Programme team are currently trying to improve water quality in the lake. If the vendace have gone from Bassenthwaite, they can be reintroduced at a later date, using fish from Loch Skene.
It is good that this can be done, but I am surprised it was allowed to happen in the first place seeing as Bassenthwaite is a designated site of special scientific interest and national nature reserve! But there again, if it hadn't been - this loss may have totally gone un-noticed!

[black]

It is sad news. Like most environmental problems its a complex issue, the catchment area for Bassenthwaite is large over 350km2. So they do need all the farmowners on their side to reduce over-grazing to stabilize the soil-erosion. Plus theres a 100km of river banks to plant up with woodland again to reduce soil erosion.
Its quite worrying the level of Phosphates in the lake and associated algal blooms. All the remediation measures to reduce the algal levels using barely straw and ultrasonic blasting seem to be unworkable for a lake this size. Even if they manage to reduce future pollution from my own involment in ocean sediments I know the effect that resuspension of material layed down over many years can have.

I'm glad to see Dr Winfields news that field trials are being conducted into a range of artificial spawning methods to keep (Vendance) eggs free from excessive silting.

[goosey]

Hi Black - have you worked with Dr Winfield then?
What caught my imagination when I heard the story on Radio Cumbria the other day was,that the vendace were only found in Bassenthwaite, then recently they were found close by in Derwentwater. This is where I start to sound cuckoo - I wondered if there was anyway they could have just "moved home" and got there themselves by way of streams or flooding or something? How did they just appear in Derwentwater?

[black]

The Vendace are 'glacial relics' from the last Ice Age. They've only probably noticed them in Derwentwater. There are a number of other fish that became trapped in other Cumbrian Lakes when the ice retreated including the Arctic char schelly.

No I've not worked with Dr Ian Winfield but I know of him he's based in Lancaster’s Centre for Ecology and Hydrology. I'm more marine science- carbon cycling.

[paul m]

I know very little about fish and had never heard of vendance (Coregonus albula) until goosey pointed us in that direction. I see that it has been reintroduced into some Scottish lochs but that its doesn't seem threatened in e.g. northern Scandinavia (indeed there are recipes on how to cook it in Lappish style!). Might atmospheric warming also be a contributory factory in British decline?