This spring there were several sessions of clearing bramble, saplings, and bracken which are stifling important old trees in Ashtead Park. Several volunteer groups and individual residents were involved, as outlined by us previously, and we intend to carry on helping to remediate this wonderful site. Councillor Hawksworth and I have been liaising with the Mole Parks Department in creating a long-term management plan for the site, and the fishing ponds are part of the remit.
Leatherhead Angling Club leases the ponds from the Council, and they have exclusive fishing rights, but they are keen to improve their part of Ashtead Park for the benefit of visitors as well as for their Club. Fish stocks have been declining. Part of the problem has been the resident pike but also the frequent visits by cormorants; they get easy fishing in Ashtead compared to being out at sea. A certain amount of predation is healthy in an enclosed system like a pond because it prevents fish populations becoming too high but, in addition to the birds and pike, there seem to be some other, insidious, factors affecting fish survival.
It is obvious that overhanging, and even submerged, branches of neglected trees around the pond has created too much shade and allowed the seepage of plant toxins into the water. This is exacerbated in the autumn when vast quantities of leaves start rotting at the pond bottom, contributing to the development of thick, organic silt. Decomposing leaves and other organic debris can create anoxic zones at the water/bottom interface and these can be toxic to fish which, of course, need aerated, toxin-free water. The vast amounts abstracted from the pond by the surrounding trees also results in shallower water and this can make the situation serious for the fish in hot summers. One only has to remember the ghastly sight of dying fish flapping about in the drying mud in Ashtead Pond last year.
The lack of much emergent vegetation around the pond edges is also a factor that might be having a negative impact on fish and the pond as a whole. Fish feed on any appropriate food they can find, and insects and other invertebrates are important components in their diet; there needs to be a healthy balance of micro-flora and micro-fauna to provide food for all the various animals living in the water to maintain a healthy food-web. There also need to be tall plants to provide support and attachment for insect larvae as they emerge into the air when they change into adult flying forms. A marginal, emergent vegetation would also provide hiding places to protect the fish from the predatory birds.
With some advice, the Leatherhead Angling Club has carried out a great deal of restoration work and, as a result, some might consider the ongoing works to be unsightly. However, plans are well underway to transform the banks and surroundings of the pond into a more natural-looking feature and, in time, the whole site will be attractive to all, as well as healthier for the fish.
Recently, Councillor Hawksworth and I met with MVDC Parks Department and the Angling Club at the pond. They wanted us to check on their restoration work, and discuss plans for further improvements; and they will be keeping in close contact with the Council at all stages of their work. They will be dredging out basal organic silt, cutting some overhanging branches, reducing the thickness of the surrounding woody plants, and then planting up pond edges, and areas that are being created by the emplacement of dredged silt. Appropriate, native aquatics and emergent plants will be introduced.
It is also planned to construct eco-friendly paths leading from the carpark to the pond and around parts of the pond itself. This will make the whole area far more accessible to visitors and especially to the disabled.
We all make a plea to dog owners to forbid their dogs from entering the water.
Councillor Patricia Wiltshire
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