Wimbledon Common Weekend of Nature
Sunday 23rd June 2024
Quekett members participated in the tenth Weekend of Nature (formerly called a BioBlitz) on Wimbledon Common (a Site of Special Scientific Interest (SSSI) and a Special Area of Conservation (SAC)) in south-west London as part of the Club’s microscopy outreach programme.
Alan Wood and Neil Henry set up their microscopes, cameras and computers in the open-fronted garage next to the Information Centre to assist with identifying plants, insects and other organisms found during the organised walks. This location makes our presence obvious to visitors, and we had lots of interest from children and their parents.
Microscopes, cameras and computers
Neil Henry brought his monocular PZO compound microscope with 4×, 10×, 20× and 40× objectives and a YW5.0M eyepiece camera sending images to S-EYE software on his laptop computer. Neil also brought a copy of Collins Field Guide to Freshwater Life by R. Fitter & R. Manuel (the 1986 edition, very popular with Quekett members) to help identify freshwater specimens. His specimens included a dragonfly nymph, snails, copepods, ostracods, nematodes, and what we think was a microturbellarian.
Neil Henry
Alan Wood brought his trinocular Olympus SZ4045 6.7× to 40× zoom stereomicroscope (with an LED ring-light) and a Canon EOS 5D Mark II digital SLR camera (controlled by EOS Utility) to show live images on his laptop computer. His specimens included some of the smaller moths from the moth trap, and plants growing near the Information Centre. He collected some filamentous algae from the new pond, and among them found ostracods, copepods and a tiny juvenile water boatman, all of which were too small or too fast to photograph.
All of the aquatic specimens were returned to the pond.
Green oak tortrix moth (Tortrix viridana)
Aphids on grass
Grass flowers
Flower of ribwort plantain (Plantago lanceolata)
There were red and blue damselflies flying over the new pond, pond skaters on the surface, and water boatmen and a newt swimming around.
New pond in the Wildlife Garden
Moth trap
Les Evans-Hill ran a UV moth trap near the Common on Saturday night and opened it in the garage on Sunday morning. He removed the cardboard egg trays that give the moths somewhere to cling to, and told us the names of many of them. Some the moths were put into glass-topped boxes so that we could admire them, and some of the smaller ones were put into tiny Petri dishes so that they could be examined under a stereomicroscope.
Opening the moth trap (Henry Wilson on the left)
Egg boxes
All of the moths were released.
Walks
There were two organised walks during the weekend, one on Saturday afternoon mainly looking for butterflies and dragonflies (led by Simon Riley, Les Evans-Hill and Angela Evans-Hill), and a general nature walk on Sunday morning (led by Henry Wilson, Oliver Bennett, Les Evans-Hill and Peter Haldane).
Simon Riley (left) leading a group across the plain
Group at Hookhamslade Pond
We saw some emperor dragonflies (Anax imperator) at Hookhamslade, but they were too far away to photograph.
Les Evans-Hill (taking macro photographs with a 300 mm lens and two tele-converters)
In 2019 we saw lots of iris sawfly larvae (Rhadinoceraea micans) at Hookhamslade Pond, and a few in 2023, but this year we did not see any.
The most abundant insects that we saw were the small grasshoppers that we disturbed when walking through the grass on the plain.
Some insects are hard to see, but their presence is obvious by the damage that they cause, such as these marble galls that contain the larvae of a tiny wasp:
Marble galls on oak (caused by Andricus kollari)
Many of the leaves on horse chestnut trees were damaged by leaf-mining caterpillars, but this does not seem to affect the health of the trees.
Leaf mines on horse chestnut (caused by Cameraria ohridella)
Brown oak tortrix (Archips crataegana) on oak
There were huge numbers of green oak tortrix moths last year, but only a few this year. Many of the oak trees were infected with a fungus that can distort the leaves:
Oak powdery mildew (Erysiphe alphitoides)
Some caterpillars are very easy to spot:
Rusty tussock moth (Orgyia antiqua) caterpillar on oak
Speckled wood (Pararge aegeria)
Nymph of red-legged shieldbug (Pentatoma rufipes) on oak
In 2023, we saw lots of poplar leaf beetles (Chrysomela populi), causing significant damage to young trees, but this year we only saw two beetles.
We were not able to identify everything that we saw, such as this cocoon:
Cocoon
Newly-emerged (teneral) adult damselflies are pale until their colours develop, so they are very difficult to identify:
Damselfly
Large red damselfly (Pyrrhosoma nymphula)
Bumblebee
Honeybee (Apis mellifera)
We haven’t seen banded snails for a few years, but this time there were several on a patch of stinging nettles:
Banded snails (Cepaea spp.) on stinging nettles
We saw lots of flowers among the grasses on the plain.
Bee orchids (Ophrys apifera)
Bird’s-foot trefoil gets its common name from the seed pods, which resemble the feet of a bird.
Bird’s-foot trefoil (Lotus corniculatus)
Tormentil (Potentilla erecta)
White clover (Trifolium repens)
Yellow loosestrife (Lysimachia vulgaris)
Other plants that we saw included:
- Grass vetchling (Lathyrus nissolia), which has leaves that resemble grasses and tiny red flowers.
- Yellow rattle (Rhinanthus minor), which was accidentally introduced to the Common. It is a parasite on grasses and is now widespread on the plain, but by thinning the grass it allows more wild flowers to grow.
Displays at base camp
On Sunday, in addition to the Quekett, other organisations had displays (including activities for children) near the Information Centre.
Wimbledon and Putney Commons Conservators had a display of photographs, maps and information about the Commons.
Information about the Commons
Friends of Wimbledon and Putney Commons brings together people who are connected by a passion for the Commons and play a crucial role in preserving, protecting and maintaining this unique and special place. Benefits of being a Friend include access to special walks, invitations to social events, and an e-newsletter.
Friends of Wimbledon and Putney Commons
Wimbledon Common Nature Club is run by Auriel Glanville, and meets on the first Sunday of the month to introduce 6 to 14 year olds to nature on Wimbledon Common.
SW15 Hedgehogs is based in Roehampton and Putney. They make people aware of the decline in hedgehog populations and how they can help to reverse it, for example by building a hedgehog highway. The have a Facebook page and they are also on X (formerly Twitter).
SW15 Hedgehogs
Reptile Events gives people the opportunity to handle reptiles in a safe environment, educates people about the animals themselves and their requirements and care as pets, and acts as a “rescue” for reptiles whose owners are unable to continue looking after them.
Reptile Events
Acknowledgements
We are grateful to the Conservators for allowing us to use the garage for our microscopes and cameras, and to collect specimens from the Common.
Members of the Quekett Microscopical Club will be in the Information Centre for Wimbledon Common Open Day on Sunday 8th September 2024.
Report and photographs by Alan Wood