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Cyngor Sir Ynys Môn - Isle of Anglesey County Council

Ecology in planning applications

Covering ecology has become increasingly important as policy and law evolves. We advise you read the following key points to help ensure your application can be accepted and processed without delays. 

What impacts could your application have on ecology? 


Your application might affect species or sites which are protected in law.

There are legal protections for species, such as bats, nesting birds and reptiles.

There is protection for designated sites such as Sites of Special Scientific Interest (SSSIs) and Special Areas of Conservation (SACs). There is also protection for Local Wildlife Sites (LWS) through local planning policy. 

If protected species or sites may be affected by a proposal, an ecological survey or assessment is likely to be required to inform the planning case. Pre-application case comments advise on this matter. 

Overall wildlife interest

Is the application likely to lead to overall losses?  

Under the Environment Wales Act (2016), the Council has a duty to seek to maintain and enhance biodiversity whilst carrying out its functions.

The Welsh Chief Planner has instructed all Heads of Planning, that

‘…where biodiversity enhancement is not proposed as part of an application, significant weight will be given to its absence, and unless other significant material considerations indicate otherwise it will be necessary to refuse permission’ (Neil Hemington, 23 October 2019). 

We therefore strongly advise that site design should retain existing wildlife interest where possible, and also include enhancement features, such as new native tree/shrub planting, addition of bat and bird boxes and/or other features. 

You should consider your proposal’s impacts both in the short term works/construction phase, and the long-term effects of changes resulting from the plan. If your proposal will lead to losses of features such as hedgerows, trees and/or ponds, then new features to make up for these should be included in the application. 

Avoiding delays 

The most common ways in which cases can be delayed for ecological reasons are: 

  • proposals show overall biodiversity losses, with lack of mitigation. Inclusion of new native planting and bird/bat boxes in design can save time significantly (bird boxes should be on north/north east/east elevations, bat boxes on south east/south/south west elevation
  • survey required, but not included with application
  • survey advises further survey, which has not been carried out
  • need to wait for survey season before survey can be undertaken (main season is normally spring and summer)
  • survey recommends mitigation features, but none included on proposal design (in some cases, addition of such features can be conditioned)
  • survey report requires changes
  • submitted survey is too old – surveys can in most cases be deemed valid for 1 – 2 years. (updates are easier than first-time surveys.)
  • non-coverage of ecology matters raised through pre-application comments
  • applications for discharge of conditions or for variation of existing permissions and conditions can require new surveys, or have to take account of new laws and policies, or new protected sites. If the condition is at least partly dependent on/relevant to information from an original survey with a time limitation extensions of existing planning permissions can require update bat surveys and so on
  • note also that some matters can be covered by planning conditions, but awareness and basic early consideration of these is advised; for example: methodology details for works phase, long-term management plan for site (normally applies to larger sites), and low-impact outside lighting plans 

Do you need an ecology survey?

The following kinds of application are the most likely to require ecological survey or assessment. 

  • conversions of outbuildings, particularly rural
  • conversions of chapels/churches
  • demolitions of many kinds of buildings
  • proposals affecting areas of natural/semi-natural habitat (especially larger site proposals)
  • proposals which may impact protected sites 

Each case is different. Advice on whether survey is required and the scope of survey takes many variables into account. Pre-application cases are advisable to help establish likely requirements. 

Survey reports should include recommendations, covering 

  • precautionary methodology to minimise risks, even if no protected species are found
  • mitigation to make up for impacts 

Protected Species Licences can be required if certain species (such as bats and crested newts for example) are found on a site. Natural Resources Wales (NRW) oversees licences separately from the planning process.