Invertebrates: surveys and mitigation for development projects

Standing advice for local planning authorities who need to assess the impacts of development on invertebrates.

Applies to England

Survey reports and mitigation plans are required for development projects that could affect protected species, as part of getting planning permission or a mitigation licence. Surveys need to show whether protected species are present in the area or nearby, and how they use the site. Mitigation plans show how you’ll avoid, reduce or manage any negative effects to protected species.

This is Natural England’s standing advice for local planning authorities who need to assess planning applications that affect invertebrates, including 3 European protected species.

This information should be used to decide what is needed for surveys and planning mitigation measures for invertebrates.

Ecologists need to decide which survey and mitigation methods are right for the project they’re working on. If this standing advice isn’t followed, they’ll have to include a statement with the planning application explaining why.

Where this guide says ‘you’ it means the ecologist.

Get more detail on how planning authorities can assess applications involving protected wildlife.

Specific guidance is available for:

How invertebrates are protected

The following invertebrates are European protected species (EPS) - they’re protected under European law:

  • large blue butterflies (eggs, caterpillars, chrysalises and adults)
  • Fisher’s estuarine moths (eggs, caterpillars, chrysalises and adults)
  • little ramshorn whirlpool snails

Where these species occur the sites are often designated as a sites of special scientific interest (SSSIs) and Special Areas of Conservation (SAC).

You’re breaking the law with these 3 species if you capture, kill, disturb or injure, on purpose or by not taking enough care.

It’s also against the law to:

  • damage or destroy a breeding or resting place (even accidentally)
  • obstruct access to their resting or sheltering places (on purpose or by not taking enough care)
  • possess, sell, control or transport live or dead protected invertebrates, or parts of them

If you’re found guilty of an offence you could get an unlimited fine and up to 6 months in prison.

Together with the EPS about 400 other species form the invertebrate species of Principal Importance in England and are included within :

EPS, Schedule 5 invertebrates and S41 priority invertebrate species are the protected and priority invertebrates that need to be taken into account in planning decisions.

Activities that can harm invertebrates

Even small areas of suitable habitat can be of high value to invertebrates. This means that even small-scale developments can harm large blue butterflies, Fisher’s estuarine moths, little ramshorn whirlpool snails and other protected or priority species.

In most cases you should be able to avoid harming them, and damaging or blocking access to their habitats.

When you need to survey

Survey for protected invertebrates if distribution and historical records suggest they may be present.

Use the National Biodiversity Network Atlas as your principal source of biological data.

Invertebrates exist in all habitats but certain habitat types are of very high value and should be considered in survey plans. These include semi-natural vegetation, wetland, coastal areas, open mosaics and previously developed brownfield land.

Field surveys

Field surveys should be carried out at the correct time of year, generally between May to early September. Use the Ecological survey and mitigation standards to help make sure your surveys are to the correct degree of standard, extent and accuracy.

Follow the Chartered Institute of Ecology and Environmental Management (CIEEM) guidance on invertebrate surveys for aquatic species and terrestrial species.

You may find these resources useful:

Assess the impacts

Assess the impacts this development would have on protected invertebrates if no mitigation measures were planned. To do this you must assess the status and importance of the species or assemblage that are affected.

The Joint Nature Conservation Committee species status assessment project establishes the risk of invertebrate extinction in the UK using International Union for Conservation of Nature methodologies.

Mitigation and compensation methods

Address the potential impacts you’ve identified on protected invertebrates and priority species with your mitigation plans.

You should aim to avoid negative effects, eg by redesigning the scheme. If this isn’t possible, use mitigation measures to reduce the impacts:

  • reduce the scale of the impact by minimising the footprint of the development
  • create new habitat
  • phasing of works and restoration activity is often important in providing habitat continuity
  • maintain sufficient suitable habitat to support the species in the local area

Due to the number of invertebrate species specific mitigation requirements these are not included within this guidance. Local planning authorities should seek a qualified ecologist’s advice about potential impacts and suitable mitigation measures.

Use compensation measures if there are still negative impacts for invertebrates.

Only move invertebrates to a new location (translocation) as a last resort.

Additional licensing information

This guidance is provided for ecologists and developers considering applying for a mitigation licence or other licence for protected species of invertebrate.

Get a licence

You might need a licence for development or other activities that could affect protected species. In most cases you should be able to avoid harming invertebrates and their habitats.

Get an EPS mitigation licence

If you can’t avoid this, you can apply for a mitigation licence for the 3 EPS species. You’ll need expert help from an ecologist.

If you need a mitigation licence or other licence, your application needs to follow the standing advice or it may be refused.

Licence exemptions

The Wildlife and Countryside Act 1981 does not provide for licences to be issued for development. In exceptional cases, where avoiding harm isn’t possible, the law allows certain exemptions to permit legal activities, eg a development with planning permission).

You might need a survey licence to survey protected invertebrates, eg in protected sites like SSSIs and SACs.

Contact the Natural England site officer to establish whether an additional consent is required.

Published 9 October 2014
Last updated 10 August 2015 + show all updates
  1. Added links to specific guidance for white-clawed crayfish and freshwater pearl mussels.

  2. First published.