Pond Restoration

Following the surveys I did in the Spring, I wrote a report for each site outlining some recommendations on how the ponds could be managed to benefit amphibians. It was great that I could join the reserves manager last week and start to make improvements to one of the ponds.

Pond clearance is best undertaken in the winter months (November to February) when amphibians are less likely to be present in the pond. Nevertheless, as the pond was known to be home to great-crested newts, only a third of the pond was worked on, leaving plenty of areas undisturbed where newts, efts and other amphibians could retreat to.

The pond was very overgrown with rushes and reeds, with hardly any open water (top photo shows the pond before any work was done). Although still a pond rather than a reed bed, without action it would dry up over the coming years. The invasive pond weed Crassula helmsii had also started to take over, forming a mat on one side of the pond and stretching several metres in.

As it's a relatively small pond, we tackled it by hand. Wearing waders, we got stuck in and found the vegetation was fairly easy to pull up from the roots. The water was also deeper than I thought, reaching mid-thigh on my waders. Whilst this bodes well for the future of the pond, it formed the natural limit of our work!  To try and avoid spreading the Crassula further, the whole mat was rolled back and piled on the side of the pond.

This is still somewhat of an experiment, but it is hoped that by covering the vegetation with black membrane it will die and decompose. We are reluctant to use any chemicals as this would harm the wildlife in the pond. It is unlikely that the Crassula will have been totally removed, but it should slow the spread. The silt stirred up during the work will soon settle and provide a nice area of open water for breeding newts to display, whilst leaving areas of vegetation for egg-laying and protection.  If successful, the work will be repeated next year to remove a further third of the vegetation, and the technique will be repeated on other ponds.