The Matthew Burn in Darvel suffered from a devastating poisoning incident in the last few days. This wee burn flows through the middle of Darvel and is culverted under the main A71 road. Deck replacement works are underway on the culvert in the Main street and downstream of this point, members of DArvel Angling Club came across a number of dead fish on Saturday. SEPA were notified and attended. In all, 3 fish were found dead. SEPA were unable to pinpoint the source of the pollution and judging by the condition of the fish, it seemed likely that whatever killed them had entered the burn towards the end of the working week and there was no obvious ongoing pollution entering the burn.

Jimmy Mair from Darvel Club called me and sent photos on Sunday morning with reports of many more dead fish. Garry Anderson and Jim had been at the burn since first thing in the morning and counted over 70 dead fish and two frogs.

Salmonids lying dead in a pool

They had collected some in a bucket and met 2 wee boys who had picked a few larger trout from the burn to take home to eat! The two youngsters were sent home for a good wash and check up minus their fish.

I called SEPA who agreed to come back out to the burn and meet with myself and the others. Jackie and David from SEPA arrived shortly after myself and were surprised by how many fish Gary and Jim had collected. There were still plenty of fish lying dead in the burn along with a selection of invertebrates.

Invertebrates were clumped in slack water… all dead too

We walked upstream and looked at the burn below the road culvert and above. Upstream the burn appeared clean and there were no signs of dead inverts or fish. Downstream, 3 fish were dead in the pool below the culvert. SEPA staff took water samples but of course there may be nothing toxic left to find as a couple of days at least have passed since the fish appear to have been killed.

We walked downstream all the way to the confluence with the River Irvine spotting dead fish and invertebrates as we went. The mainstem river was probably not affected due to dilution but we will never be certain. I took scales from several fish to identify the ages affected but I guess it will be at least 3 year classes and of course the developing embryos in the gravel are likely to have been lost too making four years of fish wiped out. I’ll look at the scales in the morning.  The bulk of the fish were trout but a few salmon were killed too. Interestingly, no stone loach, sticklebacks  eels or minnows were found. In all we picked up over 70 fish but there are bound to be many more decaying below rocks and boulders or lost to predators.

Fish and a frog collected on Sunday before and after SEPA’s visit. SEPA have taken samples for lab analysis.

SEPA will be on site again in the morning to speak to those possibly responsible for the incident. SEPA ecologists will also attend. Hopefully they will be able to clearly identify the source of the pollution. ART will assist with electrofishing surveys for the angling club if requested.

It is sickening to see lots of dead fish in such a wee burn. It is obviously an important salmonid spawning burn especially for trout. I do hope that those responsible will be identified and prosecuted. As David pointed out, fish kills are increasingly uncommon nowadays but there just can’t be any excuse for such devastation.