News & Views

There are now numerous detectors available to help ecologists monitor bats, but what are their limitations and how good are the data that they produce?  BSG has been working with Bristol University to try and come up with some answers.
On Sunday Steve Foot accompanied by Natalie White and Owain Gabb went to heathland in Surrey in search of rare reptiles. Steve regularly undertakes survey visits to this heathland and other sites as part of a monitoring scheme run by the Surrey Amphibian and Reptile Group. The Surrey ARG undertake surveys of approximately 40 sites spread throughout Surrey with new sites in neighbouring Hampshire, Berkshire and  West Sussex included this year. A number of voluntary surveyors (of which Steve is one) survey these sites each year allowing the Surrey ARG to monitor the populations and the distribution of reptiles across each of the sites.

Locating bat roosts in trees is challenging. Larger, regularly used roosts can sometimes be more obvious. For example, staining may be visible around the roost entrance hole or, if you are lucky, “chattering” bats may be heard at dusk, just before they emerge. However, roosts...

When the Bat Conservation Trust’s (BCT’s) “Bat Survey Guidelines” were published in 2007, wind farms were excluded because there was little knowledge or experience of surveying to inform a wind farm proposal. The guidance documents that did exist (principally the “Eurobats” guidance and Natural England’s guidance notes (TIN051 and TIN059)) are quite open-ended with regard to survey methods and effort and there are discrepancies between them.
Summary: In 2009 a paper by Pearce-Higgins et al (see previous BSG news and resources bulletin) concluded that operational wind farms had resulted in the displacement of a number of upland breeding bird species.  Since this time, nature conservation consultees have become concerned about displacement effects and the impacts this might have on wader populations.  Curlew, a species identified in the paper as showing a reduction in nesting density at distances of up to 800m from turbines, has been a particular concern, especially in areas (such as upland Wales) where local populations have been subject to considerable declines and are already extremely fragmented.  This has led to requests for large-scale ‘compensatory’ off site habitat management in relation to some wind farm planning applications.
Summary: A recent paper in the scientific journal Bird Study summarising the operational effects of the Beinn Tharsuinn wind farm (a Scottish Power scheme) on moorland breeding birds, draws into question the perceived wisdom that densities of golden plover are reduced in close proximity to wind turbines.  A further paper, by Natural Research, on the distribution of curlew around operational wind farms, suggests minimal effects on the distribution and population density of that species, formerly considered to be sensitive to displacement at distances of up to 800m from wind farms.

Owain Gabb will be attending Renewables Cymru, which will be held in Cardiff on 26th May 2011. Should you have any ecological or ornithological queries, Owain will be more than happy to answer them, or to direct you to someone at BSG who can...

BSG have been catching and ringing birds at the Oxford office since February 2010.  This work has been undertaken with permission from Worton Farms, and is carried out by appropriately licensed and experienced bird ringers (led by Owain Gabb).  All data collected is supplied to the British Trust for Ornithology (BTO).  The information is therefore available to be used in scientific research projects, while the ringing study provides training opportunities for some of BSG’s ecologists and detailed information to the farm on their local bird community.
A recent research paper from Sweden has confirmed that resident and migratory species of bats will fly off-shore to forage where there is a plentiful food supply. Of particular note, bats were recorded investigating an off-shore wind farm and even resting on turbines. Although the research is specific to the Swedish coast it does raise questions about whether similar behaviour is being exhibited elsewhere off the coast line of northern Europe. This research, linked to data relating to migration of Nathusius Pipistrelle bat between the UK and northern continental Europe, raises questions as to whether large off-shore wind farms should assess potential impacts on bats.
Integrating biodiversity into the built environment is an ever more important element of sustainable design. Policy guidance directs planning authorities to expect biodiversity benefit in new developments. Where space is at a premium the fabric of the built environment itself can be used to make cost-effective gains for biodiversity.