August has been a wild ride for us here at the Welsh Dee Trust and I have so much to say!
With Electrofishing season in full swing, we began the month testing out our new high-tech kit. Chris and Gareth marveled at the modern ghostbuster-esq backpack which allows you to carry both the cathode and anode on your person whilst carrying out the survey. They told me about the surveys in past years where the equipment (which looks like something out of an 80s sci-fi film) had to be placed on the river bank and moved along with the surveyors upstream whilst the survey was carried out, which you can imagine the difficulty of when bushes, trees, and steep, slippery banks are involved…
To electro-fish a body of water, the conductivity of the water must first be measured. In water with a higher conductivity (determined by saline content, temperature, etc.), a lower current needs to be used to not harm the fish. Once we determined the correct current, the fishing commenced. The stream we were surveying was full of slippery rocks and differing depths, so I’d imagine it was quite the sight to onlookers; 3 people in waders (one with a pair which was five sizes too big… I’m sure you can guess who that was…), one carrying a big hoop on a stick, one eagerly squeezing a big net in behind the anode ring, and another behind carrying the bucket ready to deposit the catch in, all scrambling over the slippery riverbed.
The current attracts the stunned (immobilised) fish towards the anode where they are then quickly scooped up and placed in the bucket, and 99% of the time, as soon as the fish enter the bucket they are back to normal. Once the first run of the survey was over, it was time to process the sample; the fish must be identified and measured before release. The identification is the easy part (even between salmon and trout once you get your eye in), the difficulty came in measuring the fish! Our measuring device (pictured below) was a simple wooden block with an embossed ruler, which might sound OK, but after a few wet and slippery fish have been measured, the slick wooden surface soon became like an ice rink…
On top of all the electrofishing this month, we have also been keeping on top of our SmartRivers sampling processing of course, but, of perhaps slightly more interest may be the training courses funded by North Wales Wildlife Trust (NWWT) that myself and Maddy have attended towards the end of August.
First up was the River Safety Training provided by TNR Outdoors. We began the day practicing getting the attention of a drowning person, throwing and catching throwlines in different scenarios and using different items to catch a person flowing downstream. After lunch we went down to the water in wetsuits, buoyancy aids and helmets, ready to pretend to drown and be saved by ourselves and our partners!
We also attended an invasive non-native species (INNS) and biosecurity training day from NWWT where we learnt about different invasive species and what we can do at the Welsh Dee Trust (and in our daily lives) to prevent their spread. Thanks to this, myself and Maddy are now ‘Biosecurity Champions’ and will be talking to our volunteers about biosecurity during sessions to make help biosecurity a natural habit!
September is set to be another busy one, with electrofishing continuing, two SmartRivers training sessions, a phosphate training session, and a few litter picks and stall days!