After three months of dry weather my New Pond is now nearly dry. What will happen next? What will the effect be on the pond? We really don't know: which is why I'm keen to let it dry out to see how the pond and its plants and animals fare.
It always seems one of the worst things that can happen to a pond: drying out.
But we’ve known for a long time that, out in the wild world, it’s not such a big disaster.
And more than 15 years ago we wrote an article in the excellent British Wildlife magazine called ‘New approaches to the management of ponds’ where we first highlighted the fact that drying out was nothing like as bad for pond wildlife as it can at first appear .
You can read that article here (scroll through to the section called ‘Drying out’ on p276 to see what we had to say on the subject back then).
And the reason it’s not so bad is that many shallow ponds naturally dry out during dry years, or if they are shallow enough, every year.
And many plants and animals that live in freshwater are perfectly happy with this arrangement – maybe as many as half of all species.
But what about in garden ponds? Well, the simple truth is we have absolutely no idea what will happen to the wildlife in the medium term in a garden pond that dries out in summer.
Probably there will be some short-term casualties. The sort of fish we keep in garden ponds will obviously not survive – although in more natural environments – say on a river floodplain – a pond that dries out only once in 5 or 10 years could still provide a valuable habitat for fish in all the intervening years. And some fish – eels spring to mind – could get away.
Things which can’t fly away, like tadpoles and newtpoles, snails, leeches and shrimps, are also destined to die. Though even here it’s not quite so simple: there are temporary pond specialist snails, like the Button Rams’s-horn, Anisus leucostoma, which live in temporary ponds and some leeches are amphibious too.
But most insects that can fly, or can recolonise by flying, like water beetles, dragonflies, mayflies, caddisflies, alderflies, water bugs, backswimmers, pond skaters – which between them make up most of the animals found in ponds – may be little affected in the medium term, as long as there is somewhere to recolonise from. And some tadpoles have already got away from the pond so the fact that a few will perish probably doesn’t matter all that much: the adults will be back next year.
And many water plants survive the summer drought period too. Even if the adult plants die, there may still be seeds or resting stages that survive the dry weather.
So I’m watching with interest what will happen to the New Pond as it is almost certain to dry out now – with just an inch of water left.
