MORE THAN A TOE IN THE WATER
Continuing the gardening theme from my last column I have come across an interesting project being run by Pond Conservation called 'The Big Pond Dip'.
For the past three years they have collected information about garden and school ponds - how big they are, how deep, and what sorts of plants they contain, and have linked this information to the ponds' inhabitants. The exercise continues this year. It will help to refine advice about how to build and maintain garden ponds for the maximum benefit of both wildlife and people. This is important because easily accessible fresh water is much rarer than it was even forty or fifty years ago.
Ponds are about the only wildlife-friendly garden feature consistently advocated by the decking-and-pot-plant instant garden brigade. As a result there must be thousands of garden ponds although most of them are small, no more than three or four square metres. Any pond is better than no pond, but there is much that can be done to improve their worth to birds, insects and amphibians. These in turn help you the gardener: birds and frogs are natural pest controllers, and what garden is not improved by having its own supply of brilliantly coloured dragonflies and damselflies?
The Big Pond Dip results, published by Pond Conservation, show that two thirds of ponds had breeding dragonflies and damselflies, and three quarters of them contained water snails, pond skaters and water beetles. Although nine out of ten ponds were visited by frogs, toads and newts, only six out of ten were used by them for breeding. This shows that they are fussier than many people think. Newts and toads are definitely more picky than frogs. Any old piece of water will not do, unless perhaps it is isolated from other, better, places. One very good finding is that half of the ponds involved were topped up with rainwater which is much to be preferred to tap water. (Having said this, there is probably a bias amongst the self-selecting respondents to the survey to manage their ponds in this way.)
The old conundrum about mixing fish and amphibians was not really solved. Frogs were found breeding more often in ponds with fish than without (although this could be that there are fewer ponds without fish to choose from). Toads do not bother too much about fish because their tadpoles are not very tasty.
When all is said and done it is the insects and snails that will be the judges of how good your pond is for wildlife. If they move in then other things will follow. Having submerged, floating and emergent plants in clean clear water is the basis for a healthy pond with thriving and varied wildlife.
If you want to know more, or join in this year's Big Pond Dip, contact Dr Jeremy Biggs or Dr Angela Julian at Pond Conservation. E-mail:firstname.lastname@example.org, Tel: 01865 48311.