Bat Surveys and Mitigation

Wildscapes bat surveys

Bat Surveys and Mitigation

Bats inhabit a wide range of structures including buildings, trees, caves and bridges, amongst others. If there is a potential that bats are present on the site of a proposed development, then by law, an appropriate level of survey is required. There are a variety of surveys that Wildscapes ecologists can undertake depending on the type of project and time of year.

All bats and their roosts are protected under The Wildlife and Countryside Act 1981 (as amended) and The Conservation of Habitats & Species Regulations 2017 (as amended).

In England, Scotland and Wales it is illegal to:

  • Intentionally or deliberately kill, injure or capture bats;
  • Deliberately disturb bats, whether at roost or not;
  • Damage, destroy or obstruct access to bat roosts;
  • Possess or transport a bat or any part of a bat, unless acquired legally; and
  • Sell, barter or exchange bats, or any part of a bat.

There are 18 species of bat in the UK. Bats are protected due to a steady decline in numbers largely as a result of lost habitats and the conversion of buildings that are typically used by bats such as barns.

A bat survey will usually be advised by a planning consultant or architect for works or developments going through a planning application.  It may also be recommended following a preliminary ecological appraisal.

As bat surveys are seasonal and mitigation measures can take some time to implement, it is important that bat surveys are conducted as early as possible in the development and planning process.

A Wildscapes CIC Ecologist surveying

Preliminary Roost Assessment

A Preliminary Roost Assessment (PRA), sometimes referred to as a daytime bat survey or bat scoping, is the first step in the process and should be conducted on any building or structure that will be impacted by the proposed works.  A PRA is designed to look for evidence of the presence of bats and determine the suitability of a structure to support roosting bats.

The survey involves an Internal and External Visual Inspection (IEVA) of the building or structure and can be undertaken at any time of year.  However, the level of visual evidence created by target species (bats and birds) may vary throughout the year due to weather conditions and human disturbance.

A Preliminary Roost Assessment will typically also include a desk study, where existing information and ecological records pertaining to the site and its surroundings are collated and reviewed.

The survey aims to identify the overall suitability of the site for bats and assess whether further bat activity surveys will be required.

Ecologist carrying out bat survey in tree

Tree Survey - Ground and Aerial Risk Assessment

A ground level roost assessment is undertaken on each tree (or group of trees) and this involves the assessment of a tree from the ground to search for Potential Roost Features (PRF).  An endoscope is used by a suitably licenced ecologist to view any cavities which are accessible from ground level. A torch and binoculars are also used to assess the canopy branches and upper canopy. Any signs of bat activity such as staining are recorded.  If Potential Roost Features are identified or if the tree is difficult to assess from ground level, then an aerial inspection will be conducted.

The Wildscapes climbing team are all City and Guilds NPTC certified in tree climbing and aerial rescue. During an aerial risk assessment, a licensed ecologist will access the upper branches of the tree using a rope and harness to further assess any Potential Roost Features which have been identified from the ground. A torch and endoscope are used to determine if bats are present and to confirm the feature suitability.

Should any proposed works be likely to affect trees which have been assessed to have bat roost potential during the aerial assessment, they are then subject to nocturnal presence/absence surveys.

Wildscapes CIC bat in hand

Nocturnal Bat Activity Survey

Often referred to as presence/absence surveys or emergence/re-entry surveys, these are required if the Preliminary Roost Assessment has identified bats (or the potential for bats).  The surveys take place at dusk and dawn and involve surveyors observing the building, tree or structure from vantage points. The aim is to determine the presence or likely absence of a bat roost within a structure and any necessary mitigation requirements.

Any bats seen to be entering or leaving the features are recorded. In addition, surveyors record any other bat activity detectable from their survey position. Where possible, the time of recording, species, the number of bats, type of activity, and flight path of observed bats are recorded.  Bats entering or leaving a building or tree are considered evidence of bat roost presence within that entity.

Nocturnal Bat Surveys are highly seasonal and typically undertaken by Wildscapes ecologists from May to September in weather conducive to bat activity, i.e. little or no rain, low wind and temperatures above 10°C. The number of surveys required (between 1 and 3) is determined during the Preliminary Roost Assessment and is dependent on the overall suitability of the site for bats.

To determine the value of a site for foraging and commuting bats, bat activity surveys can also be undertaken. These involve a combined approach of installing static board-band detectors on site and conducting transects surveys of the site and the surrounding area.  During the survey, surveyors walk a predetermined transect route to identify habitats or features of importance to foraging, commuting and roosting bats.  A transect survey should be carried out monthly between May and October. 

Bat Survey and Mitigation by Wildscapes

Bat Licensing and Mitigation

If a bat activity survey highlights the presence of roosting bats within a structure and the development cannot be altered to prevent any impact on the species, then appropriate mitigation will be required.  Work is typically unable to proceed until a European Protected Species Mitigation Licence (EPSML) is granted by the relevant statutory body. Our experienced ecologists can guide you through this process and apply for the necessary licences on your behalf.

Where the conservation importance of the roost is assessed as low following bat activity surveys and the impact of the development on bats can be easily mitigated, it may be possible to utilise a more simplified system and apply for a Bat Low Impact Class Licence.  Again, Wildscapes ecologists will advise if this is a suitable option.

Mitigation strategies vary and can take the form of the installation of several bat boxes through to the design and construction of a specific roof feature for roosting bats.  The aim is to ensure there is no detrimental effect on the bats, and strategies will be proportionate to the number of bats identified and the conservation value of the species.

Once the necessary licence has been granted, Wildscapes can offer a suitably qualified ecologist to act as an Ecological Clerk of Works (ECoW), providing supervision during the construction phase of the works and ensuring the specified mitigation measures are implemented.

Access creation and improvement

We offer a wide range of services to make sites easily accessible; from building and improving footpaths to adjoining land management and installing site furniture. We are qualified to use high quality machinery which speeds up the time of creating/improving access points where appropriate.

We provide clearance of public right of ways (PROW), and specialise in labour intensive work on sites where use of large machinery may be intrusive, inappropriate or inaccessible. We make sites more easily accessible whilst protecting wildlife. We are experienced at delivering PROW works within a wide range of habitats, be it extensive moorland habitats to urban woodlands.

Boundary work and Improvements

Wildscapes deliver boundary improvements to greenspace sites consisting of:

  • Post and wire fencing
  • Post and rail fencing
  • Vehicle barriers
  • Access points and entrance gates
  • Dry stone walling

We use locally sourced materials wherever possible, enabling you to support the local economy by working with us. Our materials are sustainably sourced, with all of our timber for our fencing being of Forest Stewardship Council (FSC) standard. This means you can be reassured that the work we deliver for you isn’t damaging to the environment.

Grounds Maintenance

Wildscapes provides competitive grounds maintenance services for a range of clients. We specialise in nature reserves, schools, neighbourhood parks and housing landscapes, bringing real quality to some of the most challenging urban locations. Our experience of involving users results in a safer and better-valued outdoor environment.

Conservation Management

We work with landowners who are required to manage their landholdings to Local Wildlife Sites, Areas of Outstanding Natural Beauty (AONB) or Sites of Special Scientific Interest (SSSI) standards, and with conservation organisations implementing enhancement or restoration works. Our experience includes woodland, wetland, meadows and heathland management, as well as maintenance for grazing infrastructure, firebreak creation and scrub clearance.

Habitat creation and restoration

We are extremely passionate about creating new habitats to be enjoyed by both people and wildlife. To add to our passion we have a proven track record in the successful delivery and creation of new habitats through our Land Management service.

We pride ourselves in constructing, managing and maintaining all types of outdoor spaces; ensuring that the clients and end-users are at the heart of service. Our team are all trained in practical land management with the relevant technical accreditations and practical conservation knowledge. Together this provides our clients the assurance that our service is safe, efficient, of the highest quality and practical to fit to the needs of users both during and on completion of projects.

Whether our clients are required to re-instate lost habitat via the planning process or are investing in local green infrastructure for employees or communities, Wildscapes has extensive experience of creating a range of natural habitats such as ponds, wetlands, flower-rich grassland, woodlands or artificial habitat such as otter holts, badger setts or water vole ditches.

Invasive Species Control

If you’re having difficulties with invasive species our land management team can help you save time and expense and also prevent you from breaking the law.

Professional support when dealing with invasive species can save time, expense and diminish health risks. Wildscapes can advise on appropriate management and differing control techniques for these problem species, and is licensed to undertake practical removal and control work on site.   Our team are experienced and trained to eradicate species such as Japanese Knot weed, giant hogweed and Himalayan balsam, which can course serious and ongoing problems for both existing and new development.

Japanese knotweed can compromise the structural integrity of buildings and pavements and if left untreated will reduce both the amenity value of a site and its commercial value. The Wildlife and Countryside Act 1981 requires that landowner or land tenants take all reasonable steps to control Japanese knotweed from infringing into adjoining land. Penalties for causing an infestation can be as serious as two years imprisonment and/or a large fine. The Environmental Protection Act 1990, Duty of Care Regulations 1991, states that cut knotweed materials and soil containing rhizomes must be disposed of as controlled waste if they are to be removed from their site origin.

The Weeds Act 1959 requires that the following plants are controlled:

  • Creeping thistle (Cirsium arvense)
  • Spear thistle (Cirsium vulgare)
  • Broad-leaved dock (Rumex obtusifolius)
  • Curled dock (Rumex crispus)
  • Common ragwort (Senecio jacobaea)

These plants do have some ecological value so action should only be taken to prevent them from spreading in large quantities to other areas or, in the case of common ragwort, to prevent them from adversely affecting livestock.

Tree planting

Our Team are experienced in the art of tree planting; whether it be habitat restoration via woodland creation in remote moorland cloughs; tree planting as part of schools or volunteer day events or planting of native hedgerow or native trees as part of landscaping schemes. We have worked for a variety of clients from large scale conservation organisations such as RSPB and National Trust, to councils, including Sheffield City Council and Rotherham MBC, and private individuals.

Moorland Conservation

Our land management team have an exceptional local knowledge and as a result have helped restore some of the most damaged areas of moorland in the UK. With expert heathland and moorland restoration skills, we work on a number of projects throughout the winter months to help stabilise bare peat. This is achieved through a combination of methods including the spreading of heather cuttings (brash) to prevent any further deterioration of the bare peat, and the planting of sphagnum and other native moorland plants to create a healthy blanket bog. We specialise in delivering moorland restoration works to remote areas, using working methods that protect the surrounding ecological and archaeological valuable habitats and features.

Wildflower ID Workshop

This course provides a day’s introduction to the identification of wildflowers with an emphasis on the most common plant families and basic flower structure.

We will spend the morning in the classroom before heading out to a local nature reserve in the afternoon.  Following the course, attendees should be able to;

– Recognise the key diagnostic features used to identify wildflowers

– Recognise members of the 9 most common families of wildflowers

– Learn to identify a number of common species

– Become familiar with the use of keys to identify species

The course is aimed at anyone with a general interest in botany, no previous knowledge is required.

Winter Tree ID Workshop

Do you know your ash from your alder?

If you do, you’ll know that ash trees have distinctive black buds, whilst the buds of the common alder often have a striking purple tinge. 

If you’re still in the dark, you can learn the secrets of tree identification in winter with this day-long course run by our Wildscapes ecologists. We will spend the morning in the classroom looking at winter identification features before heading out to a local park to practice identifying trees, and end the day with a fun quiz to test your knowledge.

The course is aimed at anybody with a general interest in tree identification, no previous knowledge is required.

An Introduction to Phase 1 Habitat Surveys

This one day course provides the detail on how to conduct a Phase 1 Habitat Survey – an essential skill for quickly surveying and mapping habitat types.

The course covers understanding how to plan, conduct and write up a Phase 1 survey. There will be a classroom-based introduction in the morning, followed by the opportunity to try out techniques in the field in a local park.

Following the course, attendees should be equipped with the skills to; 

– Understand the methodology of a Phase 1 Habitat Survey

– Be able to use mapping techniques, target notes and create a species list

– Understand the key indicator species to identify habitats

– Understand the basic report format

– Understand the options for mapping

– Understand how Phase 1 surveys are used and their role within extended surveys and PEAs

An Introduction to Bat Surveys

This one day course is aimed at people entering or working in the ecology sector who want to get an introduction to bat surveying before the start of the survey season. The course covers:

– An introduction to the biology and ecology of bats

– An introduction to the identification of British bats

– An introduction to bat legislation

– How to plan and conduct a Preliminary Roost Assessment on buildings, identifying potential for bat roosts

– How to plan and conduct ground based tree assessments, identifying potential for bat roosts

– An introduction to aerial survey techniques with a demonstration of tree climbing and use of endoscopes

– An introduction to nocturnal activity surveys

– Bat walk in a local park, practicing using bat detectors