The quick and the dead

The quick: this frog has spent the last month in my pond. But if there's enough oxygen, common frogs (Rana temporaria) can survive under ice a lot longer than this.

I had a good look at what was in the ponds today, now that all the ice has finally gone.

I was pleased to find two frogs: the one above about two thirds-grown (I took it out of the pond for this bad photo) and one full-sized adult. Both were quite lively.

Both, I’m 95% certain, have successfully survived in the bottom of the pond, under the ice.

The dead: this Emperor Dragonfly larva, which I found in the new pond today, was probably killed by being frozen solid.

Not so lucky was my fully grown Emperor Dragonfly larva, which I found today in the shallow half  (2 inches) of the new pond. I was very fond of this animal – I knew it was the only one in the pond, having netted it earlier in the autumn in the detailed surveys of our ponds, and I’d been keeping a special eye out for it. It was the fifth species of breeding dragonfly in the garden.

In this case it was in the wrong place at the wrong time: I’ve no doubt it would have survived in the slightly deeper water, only 20 cm, of the new pond’s main basin.

And this depth of water was fine for my Broad-bodied Chaser dragonfly larvae in the old pond. They were safe, happily lurking in about 25 cm of water in the ‘deep’ part of the pond, amongst the leaves and mosses, with no sign of any casualties.

As well as the dragonflies, the old pond still has plenty of mayflies, backswimmers, large red damselfly larvae – I even saw an adult Brown Diving Beetle (nice picture here) which I guess must have overwintered in the pond.

Obviously, many other people’s animals have not been so lucky as mine. Perhaps because of this, there’s been a terrific response to the request Pond Conservation put out earlier this week for information about the effects of snow and ice on ponds – the Big Pond Thaw survey. I will start posting some of the results, and commenting on specific questions, soon. Thanks to everyone who has sent back forms.

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2 Responses to “The quick and the dead”

  1. Helen Edwards Says:

    Sorry to hear about your emperor larva. Dipped the ponds here this morning – no casualties due to the cold, but our ponds are a lot deeper and we had very little snow compared with the rest of the country.

  2. Judith Lawson Says:

    I have found about 10 dead emperor dragonfly larvae this spring – so presumably it’s the cold spell in December. They should have started to emerge by now but although I’ve been looking closely I’ve seen none so far. I hope this doesn’t mean there are no survivors. However there have been lots of damsel flies emerging. Are they less susceptible?

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