Wednesday 19 May 2021

Wimbledon Park, May 2021

As temperatures and light levels increased in February and early March, planktonic plants thrived and the lake water became murky. My Secchi disk then was obscured at a depth of around 75cm. By mid May, however, enormous numbers of water fleas were feeding on the plants, leading to the annual peak in water clarity. I could still see my Secchi disk clearly resing on the lake bottom at around 180cm depth. This will allow waterweeds to thrive, providing much food and cover for fish and other water life.

I wonder if we have an incipient heronry on the island in the lake. I noticed it first in a photo I took whilst being shown round by the All England in April. There was a bird perched high up in a tree and much guano on the foliage below it, showing that the position was much-used.

Two aspects of the management of the public park are still lacking. 

First, is that the part of Ashen Grove Wood in the public park has been recognised as valuable since well before its inclusion in the Site of Borough Importance for nature conservation in Nature Conservation in Merton (1998). Subsequent work has shown that it is a tiny remnant of ancient woodland. It was being managed by benign neglect and slowly recovering elements of woodland flora beneath the trees, but has been subject to inappropriate management in recent years. First, we got the herbicide spraying around the tree bases, now fortunately stoped. However leaf litter on the ground has been blown into a windrow against the golf course fence. This removes cover for regenerating plants and helps to perpetuate bare soil with a few struggling grasses across much of the area. It makes sense to blow material off the public path on the eastern boundary of the wood but not to clear litter that's perfectly natural below a woodland canopy.

Second, is the chronic failure to repair the self-closing gate to the children's play area near the white pavilion. This was subject to a member query some years back and is perennially on the list of complaints by local residents, but nothing has been achieved. Dogs regularly enter the play area this way.