Posts Tagged ‘Wildlife’

A walk into the unknown, by Ben Oliver, Learning and Participation Manager

Wednesday, May 23rd, 2012

We’ve always known that we have bats at Westonbirt – but we’ve never really gone out looking for them.

Gloucestershire Bat Group - Miranda Winram
Previous bat walks have recorded pipistrelles and the odd Daubentons over the dewpond. Staff have found long-eared and horseshoe bats hanging in the tree team toilet. And a harp trap project last year recorded the rare Bechstein and also a whiskered bat. But this was really the sum total of our knowledge.

Was this all the species we had? Where did they fly in the arboretum? We didn’t really have answers to these questions… but then looking for small quick flying mammals at night in woodland is a bit like needles in haystacks.

However, thanks to the combined efforts of Gloucestershire Bat Group (GBG) and Forestry Commission staff (who ensured GBG members didn’t get lost) we now have a much better picture.

Assembling around 8.30pm last night seems a bit odd when you’ve only just left work – but all of us were quite excited as to what we might find (and truth be told a little nervous that we might not find much!)

The plan was to combine essential training for GBG trainees with the first bat survey transect of the arboretum using Anabat detectors. These remarkable gizmos record bats echo locating as they navigate in flight. Because different bat species echolocate at different frequencies and at different speeds it is possible for those in the know to identify the different species present by looking at their sonograms.

As dusk fell on a lovely warm day we split into three groups and headed out to our agreed survey areas – two covering Silk Wood and one in the Old Arboretum.

Armed with our detectors we were all soon hearing a variety of bat echo locating sounds including ‘smacks’, ‘ticks’ ,’clicks’ and ‘tocks’ – and of course the occasional raspberry; indicating a feeding burst as the bat closed in on its prey.

My group were given a particularly fine show in Sand Earth where we were able to watch bats spinning round Douglas fir lined amphitheatres.

Meeting back at Keeper’s Cottage, the GBG carefully reviewed the recorded sounds to identify the full list – and this was quite a revelation; as well as recording common pipistrelle, soprano pipistrelle and possibly a long-eared, the Anabats also detected serotine, noctule and two species of Myotis (the sonogram characteristics suggested Brandt’s and whiskered, but as Sandi, our bat trainer explained, she couldn’t be sure without a body). Finally another exciting possibility – a Leisler’s bat; although again this couldn’t be 100% certain from the sonogram – giving us possibly 4 new species on the night and taking the total bat species at Westonbirt to a possible 11 (out of a UK total of 18).

Whether or not it was or wasn’t a Leisler’s (or a Brandt’s for that matter) really wasn’t that important though – it was just exciting to get a glimpse of the nocturnal activities taking place on site that we had previously never really known about. And as David from the GBG said not knowing precisely provides the perfect excuse for some mist netting surveys.

Many thanks must go to the Gloucestershire Bat Group for coming out – we very much hope to continue our work together in future.

Photo: Members of the Gloucestershire Bat Group, by Miranda Winram

Useful links
Find out more about the Gloucestershire Bat Group
Become a member of the Friends of Westonbirt Arboretum
More about wildlife and bio-diversity at Westonbirt

How is ivy helpful to wildlife? by Caroline Bennett, Education Officer

Tuesday, December 6th, 2011

As part of Westonbirt’s programme of family activities this winter, Westonbirt’s education team have created a trail that explores winter traditions from around the world. Caroline Bennett, Westonbirt’s Education Officer, researched the trail and uncovered some fascinating facts about the trees and plants which are central to so many of these traditions and beliefs.

How is ivy helpful to wildlife?


The Celts in Ireland believed that ivy symbolised determination because of it’s climbing abilities.

Ivy’s flexibility makes it perfect for forming into wreaths which make beautiful winter decorations.

As ivy flowers in autumn it is excellent for wildlife, providing nectar for butterflies, bees and other insects when little else is around.

It’s berries then ripen in late winter and provide food for the blackbirds, fieldfares and thrushes who have already polished off the berries from autumn fruiting trees.

Useful links
More about family activities at Westonbirt
Become a member of the Friends of Westonbirt Arboretum

Have you visited the new bird viewing area? by Tony Pearce, volunteer

Monday, November 7th, 2011

The workshop and wood sales team of volunteers have recently completed a new bird viewing and feeding area that is accessible to visitors seven days a week, 52 weeks of the year. The previous bird viewing area had always been in the education centre, which couldn’t be accessible to visitors without staff there to open and close the building.

The new bird viewing area, located in the Old Arboretum just off Circular Drive and near to Holly Gate, is now open to the public. The RSPB have been hosting activities and working with Westonbirt Arboretum’s visitors (and wildlife) to make the most of this fantastic new facility. 

The workshop and wood sales volunteer team are a highly skilled group of volunteers who, once a brief had been agreed, began the construction of the new bird viewing area earlier this year. Here’s a closer look at how it all came together:

Initial design proposals were prepared which fitted in with other constructed elements of Westonbirt Arboretum. The design reflects the oak frame structures of the den building play in the Old Arboretum, the Great Oak Hall and the Silk Wood Barn.

The frame was made from 125mm by 125mm oak beams and 25mm larch boards to side elevations. The roof would be made from oak shingles of random widths, hanging on oak A-frames and larch purlins and battens. The design also had to let the building team manually move and lift the frame into position, and this determined the maximum length of the beams to be around 3.5m in length.

The basic design and budget was approved in early 2011, and initial milling of the oak butts was arranged with Alistair Williams for the first weekend in February.

Mobile band saw mill located along side Waste Drive. Alistair Williams operating mill with volunteers Geoff Fisher and Laurie Moir waiting to lift off cut timber.

Mobile band saw mill located along side Waste Drive. Alistair Williams operating mill with volunteers Geoff Fisher and Laurie Moir waiting to lift off cut timber.

With the timber relocated to the workshop area, material was selected for the initial components of floor and roof plates. These required an overall length of 6.6m, so three beams were scarf together using traditional framing joints to achieve the overall length. The scarf would normally use wooden pegs, but needed steel bolts to meet health and safety regulations.

The vertical posts were positioned in the floor plate and the roof plate was then located on the top of the posts. For this we used the standard mortice and tenon joint at each end of the post. All the joints were cut by hand using 50mm chisels and mallets, as through or blind joints depending on location.

Brain Young cutting mortice

Brian Young cutting mortice

Brain Carruthers and Michael Goom inspecting a roof plate

Brian Carruthers and Michael Goom inspecting a roof plate

Laurie Moir cutting tenon in post

Laurie Moir cutting tenon in post

Michael Goom  cutting housing in tie beam for roof A frame

Michael Goom cutting housing in tie beam for roof A frame

Having determined the location of the new bird viewing area, the kit was assembled in early June. The assembly of the basic frame and the raising of the roof A-frame was completed in a weekend, with all volunteers working hard over the two days.

Basic frame structure

Basic frame structure

Basic frame with roof A frames fitted

Basic frame with roof A frames fitted

At this stage of the build a delay occurred due to a requirement for planning approval. This slowed things a bit and we were only able to fit wind braces over the next eight weeks.

Marion Wilding fitting wind brace

Marion Wilding fitting wind brace

Given planning approval, all volunteers were keen to complete the project within the September target date. The boarding of the side elevations and fitting of the window frames were completed and the roofing battens, shingles and ridge were fitted over the next few weeks. During this time we were joined by a number of new recruits to the team.

New Volunteers, Roly Holtzgrave and Peter Burden, with Michael Goom

New Volunteers, Roly Holtzgrave and Peter Burden, with Michael Goom

10_11_12_near completion (1)10_11_12_near completion (2)10_11_12_near completion
With the one way windows fitted, the facility was opened for public use from 1st October. Benches were installed, leaving access for mobility scooters to enter and exit.

Some photographers have commented on the problems of taking pictures of feeding birds through the glass. This is a problem with automatic focusing cameras which has been experienced previously. It is to be noted that access for cameras have been left in the side hurdles for the serious photographers.

We hope that visitors will see this project as one which enhances their Westonbirt experience, and that birds will appreciate the new source of food when winter arrives and insects, fruits and berries are in short supply.  

My thanks go to all of the volunteers who have supported this project with their time and effort. We are now engaged on new projects, including additional play equipment for Silk Wood and some smaller projects for the Learning Centre and Family Events. In the New Year we hope that we will undertake some additional oak framing which will take the form of shelters in the arboretum.

You could help us by donating any carpenters hand tools (chisels, planes, hand saws etc) If you have any power tools please let me have details by email to