Repair work at the Heronry Pond

The Heronry Pond is being refilled from the borehole after the recent draining of the lake.

The lake was drained in order for repair work to be carried out on the concrete lining at the east end, where tree-roots had broken through and destroyed parts of the existing lining. Apparently this work was necessary to comply with the Reservoirs Act, for the lakes in Wanstead Park come under that category.

I felt it a shame that millions of gallons of water had to be drained out at this time of year, albeit the water was transferred into the adjacent Perch Pond so was useful in keeping that and the Ornamental Waters topped-up. It was the time of year that dismayed me - a time when many birds, particularly Coots and Moorhens were nesting. The Coot's nests in particular provided a strange sight, left high and dry - really high! Little Grebes did not do so well with their breeding this year, and perhaps this didn't help?

The fish in the lake were stunned and removed to another lake, but of course that is only the larger fish. Smaller ones - of which there would have been many fry at this time - were left to ever-decreasing areas of water and shallows. One positive result of this aspect was the remarkable sight of up to seven Little Egrets at a time having a feast. I suspect the fish and other creatures weren't quite so happy about things, and I suspect that possibly MILLIONS of creatures perished because of the changes in their environment.

It was interesting to be able to observe crayfish in the shallows (unfortunately the invasive North American ones - not our native species) as well as Great Pond Snails, and - distressingly, I thought - Swan Mussels lying high and dry on the drying mud and algae. I even went to the trouble of rescuing one that I thought still may be alive and depositing it in some remaining water.

swan_mussel_hp_0650Swan Mussel in Heronry Pond

The repair work is complete - you can see the lighter-coloured cement between the Northumberland Avenue gate and the refreshment Kiosk - but considering the considerable expense that this must have involved and the damage - as I see it - to the wildlife, I have to ask why when the lake was drained was the opportunity not taken at least to clear some of the accumulated debris from the pond - particularly along the east bank? An opportunity missed, I think.

Paul Ferris 4th September 2009