As I have monitored the results of meadow and hedgerow management in the park, tensions have arisen.
I did some experimental management of the hedgerows in early June. Some was in the 35-year-old hedgerow on the Tube line boundary between the Revelstoke Road car park and Horse Close Wood. This was established as a joint project between the Wimbledon Park Residents' Association and LB Merton tree officers and is still remembered by some of the school children who did the planting, now in their mid 40s. I also experimented along the 80-year-old hedgerow on the boundary with the ex-golf course north of the Athletics area. Both places had been butchered in the winter with the use of a heavy flail, leaving unsightly broken branch stumps. There were but two advantages of this. First, is the cost, the flail doing work much more cheaply than hand trimming. Second, is the avoidance of the bird breeding season, so avoiding breaking the law by harming the nests of breeding birds.
Since this butchering of the hedges, the plants had grown back and flowering stems of Bramble, Dog Rose and Native Honeysuckle were showing at the edges of the hedges. The fruits of the earlier-flowering Hawthorn and Blackthorn and the odd late Holly fruits were ripening. A few of the rose stems projected appreciably clear of the edge of the hedge, but there were many arching branches of Bramble without flowers, as is typical. This species flowers on one-year-old stems. These flowerless stems would threaten passers-by if left. So, my experimental management cut back mainly these threatening Brambles, whilst sparing the flowers and fruit, except in exceptional places where these branches stood out from the hedgerow edge. A few Dog Roses were in flower and had arched out, but these weren't long enough to intrude and I left them for people to enjoy, intending to cut them back once the flowers were over. As the work was solely on stems projecting clear of the hedge and was by hand, it was assured not to affect bird nests. Some of the Blackbirds, Song Thrushes, Robins, Dunnocks and Wrens were repeat-nesting after losing their first or second attempts and others had fledged young successfully and were embarking on their second nest of the year. I didn't search for these nests, as it's difficult to find nests in the dense shrubbery and so a search would risk disturbing them, but the birds' behaviour confirmed their presence in the hedge. My experiments confirmed that intrusive growth clear of the hedge could be removed in a responsible way.
Then, on 11th June, I was surveying the hedge on the boundary of the golf course and was disturbed to find that almost all of the flowering and fruiting stems that weren't any threat to passers-by had been cut off, leaving a straight edge with only a tiny fraction of the previous flowers and fruit. Clearly, someone had decided that the hedgerow needed pruning. They were wrong. Going on round, I found that the same pruning had been done on the eastern hedgerow as well. Not only that, but this trimming went well into the edge of the dense shrubs and alarm calls from Robins and Blackbirds told me that they were in distress. I cannot confirm what was the cause of that, but suspect it was disturbance of nests and their contents. Also, the flowers and fruit removed were no longer there for passers-by to appreciate, nor as sources of nectar and pollen for pollinating insects, nor for birds to consume the ripe fruits later in the season. Wanton harm to the wildlife and its habitat. Now, of course, if you don't survey a hedge before managing it you cannot confirm the presence of breeding birds. Failure to look is failure to find. It's commonplace for people to manage bird breeding habitat in such a way and technically they are not breaking the law. In my view, however, the choice not to look breaks the spirit of the law. At best these hedgerows have been impoverished by the management, at worst protected species have been harmed.
I will be making submissions on the future of our Merton parks in the current consultation. I don't believe that talking to local park users and seeking ways to balance the desires of all park users needs be any more expensive than is management by rote, as goodwill generates voluntary help. And we have a team of Community Payback Scheme people who could carry out sensitive management work with hand tools and could benefit from understanding why this is done.
As I did the monthly bird count on the 17th, I noted the Dave Lofthouse Glade in Horse Close Wood. The management work by the Friends is paying off. The early colour from Dandelions. Jack-by-the-hedge, Cow Parsley and Yellow-flag Iris has died back to be replaced by Creeping Buttercup, White Clover, Hybrid Hedge Bindweed, Hogweed, Meadow Buttercup and Hedge Woundwort. It looks like a wildflower meadow, even before the summer plants get going. The Cuckoo Flowers in the little triangle near the White Pavilion have died back and the grass flowers of Yorkshire Fog are prominant there now with just the odd Cat's-ear, Germander Speedwell and Nipplewort. The meadow beside the perimeter path south of the brook is also showing a few meadow species, the most interesting of which was a new listing for the public park, Wild Carrot. This species is most abundant in old meadows, so it is nice to find it here. It doesn't like acid soils, being found rather on the chalk in places south of here. So, yet another indication indication that there are no thoroughly acid soils in the heritage landscape.
Give their great decline, it was good to see that Swifts still commute long diatances to catch insects flying over the lake. Numbers are typically very variable, and they come and go, but seeing 20 at once was good. For other birds, much of the song is over, with birds intent on rearing their young, but it was good to hear Stock Doves and Song Thrushes on all sides of the public park. There were just a few Blackbirds in song, but many Wrens, a Blackcap beside the tube line in the east and a Chiffchaff in Horse Close Wood. There was a Great Spotted Woodpecker feeding its young in Horse Close Wood. I wonder if the pre-emptive spraying for possible Oak Processionary Moth has affected any of those species that feed caterpillars to their nestlings. My totals for both Blue and Great Tits were lower than they have been in most past years, but all manner of other things are possible explanations. It will be difficult to prove any adverse effect.
The Egyptian, Greylag and Canada Geese had arrived in the park for their annual moult, when they are flightless for about a month. There were some 120 Greylags, 50 Canadas and 40 Egyptians, all with their still flightless young of the year. At these times, they feed nearer to the lake, so they can retreat to safety out on the water when disturbance arrives in the public park (and also on the ex-golf course where the set-up for corporate hospitality is under way). There were 5 Great-crested Grebes on the lake, and three Grey Herons on the edge, suggesting that some fish are breeding naturally. Sadly, the incipient Heronry seems to have come to nothing this year.
I did the lake water sampling on the 19th. At 26 C, the water was well above the previous warmest June temperature and one degree above the highest in any month before. Sadly the water quality was low. The nutrient story was the same as usual: low nitrate and high phosphate, still suggesting that the lake is nitrate-limited. The Oscillatoria blue-green remained prominent, and the fauna was dominated by Daphnia magna, the big water-flea. People still set their dogs into the water, disregarding the warning notices about "blue-green algae". Myself, I'm careful to avoid exposure to the Oscillatora and I wash thoroughly on return home. Of course, the main risk is Weil's Disease, so it's essential that no open wound is exposed to the water. I found two other blue-greens, but so far not blooming. There was also quite a lot of Ulva lactuca, the miss-named "sea lettuce", and just a little Fennel Pondweed and Rigid Hornwort. I expect that the pondweed will increase and be cleared by the watesports people again, so exascerbating the nutrient problem. Many midges had emerged from the lake recently, leaving their larval exoskeletons behind. It was difficult undertaking a "kick sample" in the brook, as there was only a trickle of water, in many places flowing below the gravel surface, but I did find a large number of mosquito larvae alongside the usual water lice and shrimps. More like pond fauna than that of a brook.
