Our next event for you all is a butterfly and moth day on Sunday 27th July. Weather permitting, moths will be trapped overnight for us to see in the morning, and if the sun shines there should be plenty of butterflies to see. Please meet at 10 am in the car park on Wittering Road, Barnack – no need to book. Just a reminder – please remember to bring suitable footwear, the Hills and Holes can be difficult terrain and sandals are not advised. Hope to see lots of you there!
This is for members only but if you would like to come along please join the Friends of Barnack Hills and Holes. It’s only £5 pa and you can join on the day.
At 10.30 on a damp night in late June, people in Barnack may have wondered at a mysterious glow on the Hills and Holes. It came from the light of a dozen torches held by a group of Friends of Barnack Hills and Holes, led by Chris Gardiner, from Natural England. They had come to find a more fascinating light – that of our native glow-worm.
The glow-worm, Lampyris noctiluca, is not a worm but a brown beetle up to 25 mm long. It glows at all stages of its life (egg, larva, pupa and adult) but it is only the wingless female that glows strongly. The light-producing organ is on the underside of the tip of the abdomen and contains a layer of the chemical ’luciferin’, backed by a reflector of minute crystals. Luciferin glows with a cold, greenish light when combined with oxygen, and the glow-worm is able to turn the light on and off, possibly by regulating the supply of oxygen. The sedentary female glow-worm lights up strongly for a few weeks in summer, to attract sharp-eyed, winged males. As well as attracting a mate, the glow is a warning to predators: glow-worms taste bad and can cause vomiting. Adult glow-worms rarely feed, so after mating the female turns out her light, lay eggs and dies.
The eggs hatch into larvae after a few weeks and remain as larvae for one or two further summers. The larvae are greyish-brown, with yellow triangular markings on their sides. They are predators, feeding on small snails and slugs, which they grab with their jaws, inject with digestives juice and ingest as a mush. It is no coincidence that limestone grassland, which supports large populations of snails, is a favourite habitat of the glow-worm, although the insect can also be found on road verges, along hedgerows and in gardens. The decline in glow-worm populations in the last half century is linked with the loss of much of Britain’s chalk and limestone grassland. Another problem for glow-worms is competition from street lights and other light sources, which disrupts mating behaviour by attracting males away from the glow of the females.
Although the weather was not ideal, the Friends did find glow-worms that night in June. The glow was unmistakable, pin-point sharp and surprisingly bright. Once the rain started in earnest the reflection from the raindrops on the grass caused confusion, so the party called it a night, feeling well satisfied with the outcome of the expedition.
A hardy group of 14 friends surveyed the south-west compartment for man orchids on a very wet Saturday morning. Completing three traverses of this area of the reserve spread out in a line we managed to count and record the location of 161 man orchid flowering spikes. A significant increase in numbers on surveys in recent years but still significantly less than the peak recorded in the 1980’s. The survey only covered one sector of the reserve and casual walks along the main paths in the north west compartment can also find man orchids in flower. The previous post shows what we were looking for and the orchids are still flowering and can be seen on the reserve with a little care and time to hunt out the green/brown spikes from the green/brown vegetation! If the sunshines it is an added benefit as the butterflies will also be out, they were notably far more sensible than us and avoided a soaking!
Enjoyed a day out with the Peterborough Conservation Volunteers on Sunday 13th April.They work on various local nature conservation projects. At first sight removing new growth of Silver Birch, Hawthorn and other new bushes and trees may seem more like destruction than conservation.Unfortunately, if these bushes and trees were left undisturbed,they would grow to cover too much of the Hills and Holes and the flowers which currently carpet the open area would decline. In the Hills and Holes it is the open limestone landscape that is being conserved so that its particular habitat can continue to support its rich population of plants and wildlife . The weather was fortunately dry and mild. The outdoor work was enjoyable and fellow workers seemed to have plenty of information to pass on about findings on the reserve as work progressed. Due to the need not to disturb birds and other wildlife during the spring and early summer months it seems that they will not be further working parties like it until late summer but I shall be awaiting their future programme with interest.
The Friends of Barnack Hills and Holes (FBHH) are to hold an Open Day based at the Millstone in Barnack. This will give all visitors a chance to meet the steering committee and learn more about the plans for the nature reserve.
More details to follow but there will be an information display, photographic exhibition, Easter egg hunt, raffle etc and the opportunity to sign up to become a Founder Member of FBHH