While pond thrashing on my work experience with Matt, we went to a pond that was filled with numerous amphibians, such as frogs and newts. It had been listed as a fishing pond on the map, and the water was filled with healthy British plants, all of which point towards a diverse and productive pond. Upon reaching the pond, we could hear the croaking of marsh frogs, which are a non-native species, and shouldn’t have been in the pond. The most likely reason for their presence in this pond is that someone had them as pets, and chose to get rid of them by dumping them in a nearby pond. They are part of the genus Pelophylax, which contains the ‘green frogs’ of the Old World. We searched the pond’s banks for the different areas that we’d need to thrash for invertebrates, and found a few separate habitats. On the close bank, it was all open water, with few pondweeds and many larger snails floating in it, such as greater pond snails, and ramshorn snails. Water beetles and other smaller invertebrates lived in this area, with most of the larger, carnivorous invertebrates living deeper in the weeds.
On the left bank, there is a thicket of dense water mint, and lots of pondweeds in the water next to it. This is ideal habitat for newts, as they have covered areas to hunt and hide, as well as the large thicket of water mint, which is ideal for newts to lay their eggs on. We found two kinds of newt in the pond, including the rare and protected Great Crested Newt, which prevented us from disturbing that area of the pond further, to avoid agitating the newts. We also found a full grown Palmate Newt and a Common Frog and it’s tadpole hidden in the weeds and on the bank. On the far bank, there is an area of deep water, which can be seen by the lilies, which will only grow in places where the water is deep. The marsh frogs that Matt and I heard earlier jumped off of the bank and into the pond as we came past, although none of them sat on a lily pad. Thrashing in this section was fairly easy, and we found a good number of frog tadpoles and larvae.
Matt and I thrashed the pond for nearly an hour before we stopped. We had found a large number of amphibians and invertebrates, including water boatmen, caddisfly larvae in their cases, mayfly larvae, dragonfly larvae, damselfly larvae, various small water beetles, water skaters, greater and lesser pond snails, ramshorn snails, palmate newts, great crested newt tadpoles, common frogs and marshfrogs. This was an extremely healthy and diverse pond, with numerous predatory vertebrates, many specimens of smaller invertebrates, and abundant local flora, such as the water mint.