26th July 2012 – Dingwall Green Gym
Two Thursday’s ago our Dingwall Green Gym joined up with Simon and Lynn from Cromarty Firth Fisheries Trust to get an Electrofishing and Kick Sampling demonstration. All of us at TCV Inverness love these days; it’s something different for our volunteers, it’s educational and most of all it gives a background to the invasive species removal work we do for the Fisheries Trust.
Electrofishing itself is a means of assessing the fish stocks, species and health within a river or burn, and as the name suggests, uses electricity to stun fish so they can be temporarily caught for, in this case, species counting and measurements.
Duncan and Billy helping out Simon and Lynn
We were at Logie Burn just outside of Muir of Ord which proved to be a nice wee spot. An area of approx 16m was netted off for surveying. Although a demonstration, those happy enough to walk in water got to help out with the buckets while the rest of us watched on from the bridge. The burn is “swept” 2-3 times with an aim to catching all the fish within the netted area.
Once the area is “swept” the fish are anaesthetised for handling and measuring.
The species found in the sweep were Trout, Salmon, Eel and Lamprey.
Our volunteers enjoy a nice cup of tea, while the second sweep begins in the burn below.
The second sweep of electrofishing found all three species of lamprey found in the UK – Brook, Sea and River. Brook Lamprey are exclusively found in freshwater, and do not feed as adults. Shortly after spawning in April-June the Brook lamprey will die. The River Lamprey is found in coastal waters, but when ready to spawn migrates upstream from the sea in the autumn winter period, ready to spawn during April/May. The Sea Lamprey feed at sea for 18-24 months, and once adult they migrate into rivers around spring and early summer, ready to spawn between May/July.
The three species of Lamprey
After the Electrofishing demonstration it was then onto kick sampling. The creatures found in this method give indicators to the health and cleanliness of the water, and consistent sampling helps build up a picture over a period of time of a specific burn or river.
The caddisfly larvae is always an exciting find visually as it makes a protective case on itself using gravel, sand, plant material and other debris.
Hopefully we’ll be doing some more electrofishing with them again soon as it’s always a fun activity. A great morning was had with Simon and Lynn and I know our Dingwall Green Gym’ers really enjoyed themselves. Many thanks go to Cromarty Firth Fisheries Trust for the demonstrations from all at our end 🙂