The trout season’s coming to a close on most of our rivers, so hopefully it’s been a good year on your local for all of you.
I spent a bit of time with the Galloway Fisheries Trust and the River Clyde Foundation last week finding out about what makes for a healthy river.
Getting to see water samples from various parts of the River Clyde’s catchment brought home how important a clean river is.
The difference in each of the tanks was startling. One tributary had a menagerie of beasties that could pass for pheasant tails or hare’s ear nymphs while another was devoid of life.
A Scottish Environment Protection Agency (SEPA) report said the Clyde was in “significantly better health” than expected, with some parts of the river now graded as “excellent” after recovering from years of pollution.
The river’s overall quality was previously ranked as “bad” – the worst possible category – but improved to “moderate” in 2015.
Some stretches have now improved again.
While salmon and trout get most of the attention among anglers in Scotland, the members of the Galloway Fisheries Trust were also reinforcing that a healthy river is a diverse river.
Although they are one of the most abundant British fish, minnows inhabit clean, well-oxygenated water and are commonly found in healthy streams and rivers.
Generally swimming in shoals that considerably range in size, minnows are forever alert, darting quickly in response to food or danger that they face from every angle.
The British record minnow doesn’t even reach an ounce (13.5 drams) – and if you get one around 10cm then it would be a specimen.
But a small species like minnows being present in numbers is a good indicator that the river is healthy.
Minnows form an important part of the food chain for kingfishers and all predatory fish.
It’s a hard life being a minnow, but like sticklebacks or invertebrates they’re a vital part of the food chain and are very sensitive to pollution and changes.
There are about 40 freshwater and migratory fish in Scotland, from the ubiquitous brown trout in its various guises to rare species like the powan in Loch Lomond and Cree sparling (smelt).
They all depend on clean rivers and lochs as habitat.
Decades of pollution, invasive species and water mismanagement put some species close to extinction but fisheries, biologists and angling associations can all play a part in conservation for the future.
