Saturday, 23 January 2010

Pond Dip - January 2010

Jeremy at the garden pond blog has been receiving lots of reports of dead frogs and other pond animals resulting from the recent cold spell in the UK. I hadn't seen any dead creatures at Frog End, but our ponds are pretty deep so I decided to dip them this morning to see what I could find. I was pleased to find lots of animals happily swimming around and not a single dead creature.

Every dip with the net came back with a number of water slaters - they're definitely the most common species of animal in our ponds that can be seen with the naked eye:


Many of the nets contained water snails and quite a few had baby smooth newts. The newts seem to be doing fine despite the cold weather, probably because our ponds are quite deep and it was easy for them not to get caught in the ice. I found a few leeches and one damselfly larva, but it was very small and I may have missed others amongst all the vegetation that I pulled out. The main absences compared with when I dipped the ponds last summer were a lack of mayfly larvae and pond skaters.

The most exciting discoveries of the day were a bug and a beetle. As when I dipped the small pond in the summer I found a backswimmer, but I also found a common black diving beetle in the larger pond - a new species for Frog End.

Backswimmer in the usual upside-down position:


After a frustrating 10 minutes trying to get it to turn over in the water I resorted to taking it out of the water for a couple of seconds:


Common black diving beetle (I had a feeling my photos were going to be poor so I shot a video as well):

video

Unlike Jeremy I didn't find any dead dragonfly larvae, but nor did I find any live ones. Not that I'm concerned because I know that several species are breeding in the ponds and it's been difficult to find the larvae in the past - mainly due to the depth of the ponds and the large amount of vegetation they contain.

If you have a pond in the UK you can help UK charity Pond Conservation understand the effects of the cold spell by taking part in the Big Pond Thaw Survey.

1 comment:

Scriptor Senex said...

No need to worry about taking the backswimmer out of the water. They fly from pond to pond to colonise new ponds so they can obviously survive out of the water OK.