The 7th August was warm but overcast and five people met at the Dipping Platform to see what we could find. We had with us a pond dipping pack from OPAL, who are organising a nation wide pond dipping survey. First we had to test the clarity of the water on a scale that OPAL had devised and then check the pH. The water was absolutely clear and the pH was neutral, so that was a good start.
We now had to dip for insects and were accorded scores against each type we found in the pond. A score of over 31 would mean the pond was very healthy. The eventual score was 68, well above the threshhold we hoped to beat. Although we didn’t manage to find a dragonfly larva we did find lots of damselfly, caddisfly,mayfly and alderfly larva. There were also water stick-insects, pond skaters, back swimmers, water boatmen, water slaters, shrimps, two types of water snail, water mites, whirligig beetles and water beetles. The star catch was a small Three-spined Loach.
Having plumbed the depths of the Small Gravel Pit we decided to give the Deep Pit a go as we expected a different fauna would be found. We were not dissapointed. First we did the water purity tests and again the water was clear and neutral. This pit lives up to its name and a foot or so from the bank you couldn’t touch the bottom. The first creatures caught were shrimps, in good numbers and most of them were mating. There were few insects on the water surface and not such a variety as in the Small Gravel Pit. As we could not trawl the bottom we did not catch many of the bottom dwelling insects, but we did manage a few water boatmen. We eventually managed a score of 38, so the pond was very healthy and we would probably have got a higher score if we could have reached the bottom as I know that damselflies breed in this pit. This pit’s highlight was a Ten-spined Stickleback, which we did not know was on the site.
On the Wednesday the weather was not so kind, in fact it was awful, pouring with rain at one point yet there were still seven people ready to brave the elements, including two little girls as we tried our luck on the Slurry Lagoon. We tested for clarity and pH again to start off. As there was a strong wind there were waves lapping at the shore and a lot of sediment was stirred up. This gave us a zero score for water clarity but I am sure on a calm day the water would be almost clear. The pH was again neutral. We did not manage to catch as many animals as in the Small Gravel Pit again but we did reach a score of 38 again, with two types of water boatmen and some tiny mussel shells. This time the highlight was a Smooth Newt tadpole, and we also caught several Three-spined Sticklebacks.
The Large Gravel Pit will have to be done another day, but we expect rich pickings will be found when we do.