Mystery of fish deaths at Lanark Loch

Lanark Loch'21/3/11'Picture by Lindsay Addison
Lanark Loch'21/3/11'Picture by Lindsay Addison

MYSTERY this week surrounds the mass death of the carp populating Lanark Loch.

The unpleasant sight of dead fish on the surface of the loch has been reported to the Gazette by various folk who regularly walk around the body of water, long the home to a regularly replenished colony of carp, paid for by the local anglers who use the loch for sport.

The anglers, members of the Scottish Carp Group, have ploughed many thousands of pounds of their own money over the years into maintaining the colony but something has gone badly wrong with the latest generation of fish.

Many of them have mysteriously perished since being introduced to the waters at the end of last year.

Said one dog-walker this week: “It has been happening for a few weeks but last week there were at least seven carp either floating on the surface dead or obviously near to death just under the surface.”

A few years ago the marine life in the loch was badly hit when there was oil pollution into the waters, thought to be via burns from the industrial estate at Caldwellside.

However, this time pollution is not being instantly identified as the killer.

The chairman of the Scottish Carp Group, Saul Gardiner, told the Gazette: “We don’t know yet what has happened here and the cause is still under investigation.

“It is very upsetting for the members as they’ve invested a lot in their subscriptions in keeping the loch stocked.

“It seems it is the carp from the 60 new fish introduced to the loch at the tailend of last year which are dying.

“There could be several reasons for this, like the new fish not having immunity to infections from the established carp.

“It’s a bit like these stories you hear of tribes deep in the jungle who have never had any contact with the outside world and, when they do, they all come down with colds and all sorts of other infections they had been totally insulated from until then.”

He added, interestingly, that the dead carp might have fallen victim to something we associate more with human beings in today’s high-pressure world - stress!

It is a fact that carp are highly prone to fatal stress, and it just could be the case that the `new’ carp in the loch are just not getting on with the established fish there!

Whatever, the investigations are now in the hands of a branch of the government’s MarineScotland agency and post mortem results are expected in the next week or so.

In the meantime, the Scottish Carp Group has asked that other possible causes be looked into, including the current water quality of Lanark Loch.

There have been fears amongst anglers that the loch waters might be victim to occasional seepage of pollutants from `former industrial’ sites nearby.

Older readers will remember that Lanark’s main public cowp was once situated where there is now parkland between the loch and Racecourse.