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Bats can live up to 30 years. After spending the winter hibernating, bats will now be fully active and feeding. At first light or dusk, on warm dry days, is the best time to look out for them. Some hunt high in the sky while others swoop low over water. The females, which will have been pregnant since the autumn mating season, will set up nursery colonies in May and then give birth to a single pup, usually in June. These pups are very small and, as bats are mammals, will be suckled until they learn to fly and hunt insects for themselves by August.
Although different species frequent different areas, a landscape generally favourable to bats includes varied sites to roost in, such as old buildings, caves, and hollow trees; hedgerows along which to commute to and from foraging areas, woods, copses, lakes, and ponds. This seems to be a rather good description of the Nadder Valley, and it seems to suit bats. Last year, the South Wiltshire Greater Horseshoe Bat Project carried out a programme of acoustic surveys using bat detectors across 40 locations in the Nadder Valley. Of the 18 bat species found in the UK, they detected 13 species, both common and rare. At the same time, a small stone mine was monitored, and this confirmed that it is used by several rarer bats, including the greater horseshoe bat. These data contribute significantly to the knowledge of bats in the area. Unfortunately, bat populations declined severely during the last century. In common with most bat species, those found in the UK feed on insects. Given that even a single tiny pipistrelle bat can eat more than 3000 insects in a night, the well documented fall in insect numbers in our countryside is likely to be contributing to this decline. If they cannot get sufficient food in autumn, when they are building up fat reserves to get them through the torpor and hibernation of winter, they will perish. They are also vulnerable to a range of other factors such as loss and fragmentation of habitat, destruction of roosts, and predation. Bats and their roosts are protected by law, but are still under threat from building and development work that affect the old buildings and trees where they roost or set up maternity colonies. by Andrew Graham  Chris Downer / Fisherton de la Mere: Fisherton Mill [commons.wikipedia.org] Peter Shallcross will be leading a river walk from Wylye to Fisherton de la Mere this coming Thursday, starting at 7pm. The distance along the footpath beside the river is around a mile each way, pretty flat and sound along its length, so not particularly onerous.
Members don't need to register but if you'd like to come as a guest please let us know via the contact form. To share car spaces and conserve fuel, meet at the Nadder Centre car park at 6:30PM or alternatively make your own way to Wylye for 7:00PM. The rendezvous point is a layby immediately after the river bridge on the main road north of Wylye, after passing the Bell pub on your right: see https://goo.gl/maps/9jAP7xYZqvhWn3Qp6 And you may care to bring with you a picnic to enjoy in the churchyard before heading home again. Gareth Harris of the Wiltshire Bat Group has sent us an update on The South Wiltshire Greater Horseshoe Bat Project which was launched in October 2020. As Gareth remarks in his update, “a considerable volume of work has been achieved” including the enhancement of roosting sites, hibernation counts and large-scale bat detector & dung beetle surveys. Further information from Gareth “During 2021, over 50 locations were surveyed for bats using static bat detectors, recording around 700,000 sound files, over 376 nights of survey, generating records of 13 species of bat. Notably this included many new records of foraging Greater horseshoe bat, as well as other rarer species of bat such as Barbastelle bat, Leisler’s bat and Lesser horseshoe. The map below illustrates the spread of locations surveyed in 2021, and then specifically which of these recorded Greater horseshoe bat. Given the importance of the Nadder valley, hosting Chilmark Quarries SSSI for example, it is unsurprising to see this area recorded such a high activity of Greater horseshoe bat. The project also initiated landscape-scale surveys for dung beetles; dung beetles are a major food source for adult and juvenile Greater horseshoe bats throughout the year (including during the winter months). Surveys were undertaken close to roosting sites of greater horseshoes as well as the wider landscape. This work feeds into partnership working with local farmers, promoting the importance of dung beetles in soil health, carbon sequestration, and also in managing livestock endoparasites. There is growing evidence that a diverse dung beetle assemblage may reduce the requirement to use livestock worming products which decimate the wider soil invertebrate community, including dung beetles.” The Wiltshire Bat Group will be releasing further updates on their website in due course, so you’ll be able to find out more about the impacts of their bat and dung beetle surveys there.  Mark Elliott of the Devon Wildlife Trust gave a fascinating talk to the Society’s February meeting on the reintroduction of beavers into the UK, based on his experience as leader of the Trust’s project on the River Otter in south Devon.
As he explained, beavers are a species native to Britain that were hunted to extinction roughly 400 years ago. As they are no longer regarded as ‘ordinarily resident’ they can only be released into the countryside with a licence; but things are changing now, as a result of the success of the Devon trials. Last August DEFRA confirmed that the River Otters trial had been sufficiently successful for the beavers to stay indefinitely, and support will now be provided for similar managed projects elsewhere. This outcome could not have been foreseen at the start of the Devon programme back in 2015. Mark showed us how these semi-aquatic rodents had interacted with the environment on the Otter, showing how the population had grown and migrated along the river catchment over the period since then. From two founding family groups the number had grown to around 13 territories in 2019. At the outset Mark dispelled the popular misconception beavers eat fish; they are strict vegetarians. And he showed the results of work carried out by the Universities of Exeter and Southampton to measure the beaver’s impacts on fish and other wildlife. The increased variety of habitats that result from the beavers’ dams (that periodically get washed away and then rebuilt) have led to enhanced fish populations of all types and sizes, and the wetlands that result are ideal breeding and feeding grounds for frogs and for wildfowl. The water storage capacity of the river catchment has increased, and water quality downstream has improved, with lower levels of sediment, nitrogen and phosphorus downstream of the beavers than in the upstream input, and an increase in the concentration of dissolved carbon. He didn’t disguise occasional problems that have resulted from damage to crops of sweetcorn and flooding of adjacent grazing land, but showed how these can be managed effectively. Overall the experience in Devon is that the beavers are popular and, if the initial introduction is managed wisely, can exist alongside the human population to provide benefits to our environment. You can read more about the Devon beaver population and Mark Elliott’s ongoing work by visiting: www.devonwildlifetrust.org/what-we-do/our-projects/river-otter-beaver-trial Dick Budden  Our 40th Annual General Meeting starts at 7:00pm in the Victoria Hall, Tisbury. All are welcome to attend.
The talk starts at 7:30pm. If you haven't already signed up to the talk and want to come, please let us know via the Contact form. We can also send out Zoom links for those who prefer to stay at home. Guests welcome for £2 per ticket. Our speaker, Mark Elliott heads the project being carried on by Devon Wildlife Trust on the River Otter that has led beaver conservation in the UK for more than ten years. He will be able to describe their work, what we have learned as a result about this amazing animal, how they can benefit us and the landscape around us, and how we can manage potential conflicts with land owners and residents. Photo credit: Eurasian beaver (Castor fiber). Per Harald Olsen, CC BY-SA 3.0 via Wikimedia Commons Jemma Batten, Black Sheep Countryside Management -Managing for wildlife on the Salisbury Plain21/10/2021
Jemma Batten gave the talk which had been postponed from September. She explained how she was invited to work as a consultant by the Defence Estates Licensees and Tenants Association (DELTA). These tenant farmers of the MoD-owned Salisbury Plain have set up Plain Conservation https://plainconservation.co.uk/ to work together “to enhance habitats, and protect wildlife, historic and landscape features, water and soils.”  Pheasant's eye -Adonis annua. © Krzysztof Ziarnek, Wiki Commons Jemma advises on how to deliver the key conservation objectives from the detailed plans drawn up by all the stakeholders. We saw examples on-screen of all the various mapping layers of Salisbury Plain. Areas are graded from low to high priority for land management reasons or the encouragement of native flora and wildlife. We were fascinated to see that there were also Super Plans which drilled down to field level detail where named plants such as horseshoe vetch and bastard toadflax on chalk downland and pheasant’s eye on arable fields were protected by sensitive management and where the wildflower field margins would stretch to 30 metres in places. Fertilisers are no longer used and wilding practices of leaving mown areas for seed dropping have helped contribute to the increased appearance of Britain’s rarest butterflies like the marsh fritillary, adonis blue and brown hairstreak and the shrill carder bee, Britain’s rarest bumblebee. Birds such as the bittern, hen harrier and stone curlew are also being seen more widely as the marsh and grasslands improve in quality.
We learnt that staying on top of the fast-growing scrub needs to be actioned every two months, either by tractor or by mob grazing cattle. Grazing areas are marked out by erecting temporary electric fences that need moving every 2-3 days. A time-consuming task, so some farmers set up virtual fences and use radio activated collars on the cattle which bleep when they are within feet of a virtual fence and then administer a mild electric shock if they cross over the “line”. The cows soon learn! Being a military zone, not only are there pockets of dangerous or simply inaccessible places on Salisbury Plain, but farmers also have to respond immediately to commands to move their herds, often with zero notice. We expressed awe in the face of what is obviously a complicated and heavily monitored way of farming on Salisbury Plain. There is no doubt that these chalk grasslands have benefited from the strict measures put in place over the last 20 years to bring a healthier bio-diversity to an area that, though never having had artificial fertilisers or pesticides, has in the past been neglected. The passion for conservation runs deep with these farmers, so take a look at their DELTA website to learn more about their work https://plainconservation.co.uk/ Please refer to the Gov.UK website for guidance about the public access of Salisbury Plain and always ring 01980 674763 before a visit. An answer phone recording gives up to date information on areas open for public access. https://www.gov.uk/guidance/public-access-to-military-areas#salisbury-plain  Photo: Dick Budden, Sunset on the Nadder 18 July 2021 We know from the survey undertaken last year further up the Nadder near Weaveland Farm, that this area is phenomenally popular with bats. Then, 5297 passes were recorded from a total of 10 identified species, over a month. This year, Peter G Thompson (who gave us our first Zoom talk last Autumn) placed a static bat monitor on one of the bridges over the Nadder in Dick Budden's patch for five nights in early July. It recorded 10,000 hits, i.e. 2,000 each night on average, with 13 different bat species = 75% of all the species resident in UK! The species were: Barbastelle bat (Barbastella barbastellus) Brandt’s bat (Myotis brandtii) Brown long-eared bat (Plecotus auritus) Common pipistrelle (Pipistrellus pipistrellus) Daubenton’s bat (Myotis daubentonii) Greater horseshoe bat (Rhinolophus ferrumequinum) Leisler’s bat (Nyctalus leisleri) Lesser horseshoe bat (Rhinolophus hipposideros) Natterer’s bat (Myotis nattereri) Noctule (Nyctalus noctula) Serotine (Eptesicus serotinus) Soprano pipistrelle (Pipistrellus pygmaeus) Whiskered bat (Myotis mystacinus) The survey on this stretch of the Nadder is part of a programme Peter is working on to map the bat population along the Nadder from Tisbury all the way to Barford St Martin by the end of this summer. Hopefully we’ll get him to share with us the results in due course.  Pipistrellus nathusii Mnolf, CC BY-SA 3.0, via Wikimedia Commons Meanwhile, these tiny creatures do sometimes live the most extraordinary lives. The Guardian reported that a Nathusius's Pipistrelle (we have only the Common kind) weighting just 8g (I don't think my scales would even weigh that little), flew 1,200 miles - and ended up being killed by a cat.
Life isn't fair, for bats any more than it is for humans. Organiser: Debbie Carter
Following Tom Morath's talk in April about the Hawk Conservancy Trust's history, we visited the trust near Andover. The Trust does exciting work with species worldwide but also has a number of research and conservation projects focused on kestrels and tawny owls - whose populations are now 'of concern' - and barn owls and the impact of declining prey populations such as rabbits, almost wiped out by mixomatosis. More encouragingly, banning organochlorine pesticides seems to be helping recovery. Many are the joys of cat ownership - the comforting furry purry warmth, the welcoming miaow. The changing of the litter tray. The lugging home the crates of food. But there can be the downside of predation. The presentation of voles, woodmice, shrews- or even larger mammals such as rabbits and squirrels - and birds of different sizes and volume of plumage. Most cat owners feel pretty bad about this, but up to now there seemed to be little that could be done to prevent it. The verdict was, 'it's their natural instinct.' But at last, help may be at hand. The Guardian has publicised research which has identified things owners of predatory cats (not all are) can do to minimise this habit. The most effective were found to be: Play with the cat for 5-10 minutes a day using something like the DaBird fishing rod toy from Pets at Home
Put a brightly-coloured, flashy 'ruff' collar on the cat with a noisy bell (but a bell alone isn't any good)
Over a couple of months, in at least one case this has achieved a substantial and welcome reduction in predation. And cat owners may also like to know that the plastic food pouches can now be recycled - in aid of the Wiltshire Air Ambulance - via this website. Some 20 adult members and non-members, plus half a dozen young people, took part in the evening bat walk at Old Wardour Castle. It was heavily over-subscribed, so our apologies to those who were disappointed - maybe we can organise a re-run.
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Photo: Barn owl
(Andrew Carter) The headers display photos taken by our members. Do get in touch via the Contact Form if you'd like to submit a photo for selection.
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