Practical techniques: Birds
UK and Ireland
There are over 250 species of bird that breed in the UK, including residents and summer visitors. Additionally, around another 60 are purely or mainly winter visitors, for whom the UK is a vital winter feeding ground. There are also around 60 species of migrants that neither breed nor winter in the UK use it as an important stopping post on spring and autumn migration. Bird populations in Ireland tend to be less diverse than those found in the UK, but are nevertheless largely similar to the resident and migrant species of Britain. Birds breed in nearly all habitats, from bare ground through to woodland, and therefore their nests may be found almost anywhere. The breeding season for the majority of species extends from March through to August, though some species may nest earlier or later in the year, especially in times of good weather and food supplies.
Protection and its implications
The best sites for birds (breeding or wintering) are largely protected from damage by development through their inclusion within designated sites, including:
- Special Protection Areas (SPAs)
- Sites of Special Scientific Interest (SSSIs)
- Areas of Special Scientific Interest (ASSIs)
- Natural Heritage Areas (NHAs)
- National Nature Reserves (NNRs)
- Local Nature Reserves (LNRs)
- Non-statutory Local Sites
The protection of these sites is described elsewhere in this handbook. Proposed development quite some distance from sites designated for birds can come under close scrutiny by the planning authority. For example, a residential development within 400m of a SPA in southern England can be blocked because of its potential effects on breeding birds, while development further away from this same site may be subject to provision of new, large scale public open space. Another example is windfarms which lie within 15km of Special Protection Areas. Outside of designated sites, there are essentially three main levels of protection that apply:
1. Those listed on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended) and the Wildlife (Northern Ireland) Order 1985 which have protection from disturbance while they are breeding, such protection is additional to the general protection given to all birds
2. Those species on a list of priority species which should be considered by the local planning authorities when determining planning applications. In addition, further species may be identified as priorities for action at a local level in the relevant Local Biodiversity Action Plans or on local Priority Lists
3. In England, Wales and Scotland, all birds and their eggs and nests of (including Schedule 1 and priority species) are protected under the Wildlife and Countryside Act. In Northern Ireland and Ireland, similar protection is provided by the Wildlife (Northern Ireland) Order 1985 and the Wildlife Act 1976, as amended, respectively.
There are also a handful of rare species whose nests are protected even when the nests are not in use.
Given the wide variety of bird species found in the UK and Ireland and the variety of sites used for nesting, almost all development sites have the potential to support nesting birds.
Species listed on Schedule 1 (such as kingfisher, barn owl and black redstart) do occasionally breed on or near development sites and, when this is the case, careful planning of the work will be required to avoid disturbing the birds while they are nesting. A more typical situation is that one or two national or local priority species are present on the site, along with several more common species without specific legal protection. It is increasingly likely that the applicant will be required by the local planning authority to accommodate priority species, within the new development by protecting existing habitat or providing replacement habitat. This is especially the case for development which is subject to an EIA. With other bird species, it is often sufficient simply to avoid offences under the Wildlife and Countryside Act by undertaking site clearance outside the bird breeding season. Whilst this may allow compliance with the law, bird populations will be eroded if the habitat is not replaced.
Ecologists’ reports sometimes refer to birds on the ‘Red List’ and ‘Amber List’ or as included in the Red Data Book. These listings do not confer any specific protection to birds, but can be useful when assessing the importance of the site for birds.
Mitigation techniques
Killing and injuring adult birds on most development sites does not usually occur because they are generally able to escape the movements of site machinery. Exceptions may be new roads and wind farms and special considerations would apply to these types of development if birds are likely to be affected. Birds’ nests, eggs and nestlings, however, are vulnerable whenever vegetation is cleared or buildings demolished during the bird breeding season. There may be ways around this such as checking for potential nest sites prior to site clearance. However, if birds’ nests are found then these will have to be protected until after the young have fledged. By far the easiest solution, then, is to undertake site clearance and building demolition between September and February when birds are not breeding.
If Schedule 1 species have been found on the site, it is even more important either that works close to the nest site are not undertaken during the bird breeding season or the potential nest sites are removed before the breeding season commences. The nest sites of a very small number of rare bird species that re-use their nests are protected even when the nest is not occupied. If a development is planned for a site which is used as an important feeding area by wintering wildfowl, then appropriate mitigation would be to create a suitable alternative area near to the site. This would be a legal requirement under the Habitat Regulations, if there was a link between the site and a SPA or Ramsar site.
Maintaining habitats for birds
The layout of the development should be designed to retain habitats such as trees and hedgerows if possible. In addition, most new developments will include some areas of landscaping or public open space and, of course, there may well be a new building on the site. All these features may offer foraging or nesting opportunities and can be designed or managed in a way to benefit a range of bird species.
Methods can be used to reinstate or improve conditions for birds on a site following development. These include:
- Allowing the growth of ‘wild’ areas of long grass, thistles and teasels in selected areas and maintaining areas of short grass to provide foraging opportunities for different species of bird
- Providing wet areas that birds can use for drinking or for collecting mud for nest building
- Planting native trees, hedges and bushes, particularly those that support good numbers of insects or produce berries in the autumn, to provide foraging opportunities and nest sites
- Putting nest-boxes on trees and incorporating nest sites into new buildings – a range of different designs can be used
Management of the habitat will also influence its attractiveness for birds. For example, in suburban areas, tall thick hedges that are cut only once every two or three years and have a few trees are likely to support more birds than box-cut hedges which lack trees and are trimmed once a year or more. Some large urban areas support a rare breeding bird, the black redstart, listed on Schedule 1 of the Wildlife and Countryside Act. The black redstart likes derelict sites amongst tall buildings, often alongside waterways. Redevelopment of brownfield sites can therefore affect this species. Green roofs can be designed to offer the same sort of sparse vegetation that is found on derelict sites and therefore offer good foraging habitat for this species.
Post-development monitoring
Post-development monitoring is only likely to be required when rare or specially protected bird species are affected by development. The methods used to monitor bird species vary and specialist advice should be sought to identify an appropriate technique and the best time of year during which to undertake the survey work.
Timing of works
The breeding season of most bird species runs from March to August. Therefore, works that may affect breeding birds (such as removing trees and bushes or demolishing buildings) should not be carried out during this period. However, if this is not possible, then a careful check for the presence of nests can be carried out, and work may commence if no active or occupied nests are found.
Further reading
Barn Owl Trust (2002) Barn Owls on Site. EN, Peterborough
The Royal Society for the Protection of Birds (RSPB) produces a series of management case studies and technical reports, each giving specific details of different habitat management and enhancement techniques for birds
The British Trust for Ornithology (BTO) also produces a series of guides, including a nest box guide.
Natural England (2015) Wild birds: surveys and mitigation for development projects. https://www.gov.uk/guidance/wild-birds-surveys-and-mitigation-for-development-projects