It’s a busy summer for the Wildlife Trust in Cambridgeshire - and do you know your bats?
From maintenance work to surveys, reserve teams and volunteers with the Wildlife Trust in Cambridgeshire are hard at work improving habitats – and there’s a chance to go echolocating with bats, writes Caroline Fitton.
This summer for the Wildlife Trust in Cambridgeshire there’s no such thing as ‘the silly season’: there is always work to be done, and summer is inevitably the time to fix infrastructure countywide – from boardwalks and interpretation signs to fences and fallen trees.
And now with the aftermath and impacts of heatwave and drought to contend with - along with the political fallout and concern over just who will stick up for the environment in Westminster - summer seems very far from being deemed silly or lightweight anymore.
The team have been especially busy at Brampton Wood, where different sections of trees are felled on rotation producing large amounts of wood (some may be removal of non native conifer, some have been coppiced, and some more latterly is infected with ash dieback).
Dead wood is important for many forms of life in a woodland but it can also be used for producing firewood and charcoal. With the help of volunteer site wardens last month the reserves team used machinery to pull these logs onto paths for easier access, before transporting them to the wood yard for later collection.
Recent work has included cutting back rides and glades, which happens on rotation - Brampton Wood has retained significant areas of wildflower grassland of different types (almost entirely lost from the surrounding countryside) along with a wide range of invertebrate species such as butterflies associated with it.
Restoring the original width of rides and ensuring grassland connections between rides and glades allows the associated open space species to spread throughout the wood - these areas cover around five per cent of the woodland.
Some areas require that trees and shrubs are not coppiced but layered (similar to hedge laying) to maintain the living plants especially blackthorn bushes for the nationally rare black hairstreak butterfly and ground nesting birds – the wood supports a high proportion of invertebrate species including butterflies.
Ongoing careful management has seen greater numbers of populations of various species of butterfly this year: purple emperors benefit from the increased area of open woodland, especially ride edges and recently restored parts where sallows are one of the early colonisers.
Striking white admirals, seen in especially good numbers this year, benefit from the abundant honeysuckle found throughout the wood and especially the plants growing in partial shade on woodland edges.
Thinning of a proportion of canopy ash trees is under way and being completed in areas of the wood mainly due to the effects of ash dieback disease - these areas will have up to 30 per cent of the ash trees removed to allow greater light to reach to the woodland floor, stimulating tree and shrub regeneration.
Tune in to International Bat Night
Flitting out of the rising darkness like shadows, these nocturnal mammals are as charismatic as they are misunderstood. Britain is home to 18 species of bat, the largest being the noctule weighing as little as four £1 coins, and the smallest, the pipistrelle, weighing as little as a 2p coin – but known to gobble up more than 500 insects in an hour!
Whether in woodlands or skimming over a river, the sight of a bat quickens the heart. Most active in the summer months when they come out of hibernation, bats hunt insects, give birth and raise young, with the best time to see them around sunset or sunrise when it is warm and dry.
While some bats fly relatively high, others are found closer to the ground – not venturing far above the trees or flying low over grassland and water. To really experience the world of bats it’s worth borrowing a hand held detector to tune into the high-frequency clicks and buzzes of bats using echolocation to hunt; the frequency of the calls allows identification in the dark . . .
This Saturday (August 27) is International Bat Night and to mark the occasion the trust are running various bat events: an evening walk in Cambourne, 8-10pm, with bat detectors provided, while at the Great Fen, monitoring officer Henry Stanier will be leading a walk at Woodwalton Fen.
With a fascination for bats for over 30 years, Henry has applied this enthusiasm to his work in monitoring the success of the Great Fen, including training volunteers in bat survey skills.
His interest in bats has taken him to Australia, Costa Rica and Hungary, and he has run many courses on bat identification. There's also a walk in Cambridge with the trust's local group at Paradise nature reserve.
Visit www.wildlifebcn.org/get-involved/wild-events-and-experiences/bats.
The trust has a range of bat detectors - each bat species has its own unique call frequency, so by adjusting the frequency it's possible to identify the species being detected.