Ecological compliance for development projects

Several overlapping laws protect wildlife and habitats on development sites. The Wildlife and Countryside Act 1981 protects most wild birds and their nests. The Conservation of Habitats and Species Regulations 2017 give additional protection to European Protected Species such as bats, great crested newts, and dormice. The Environment Act 2021 introduced mandatory biodiversity net gain for most developments. Understanding which laws apply to your site is the essential first step.

Before submitting a planning application, you will almost certainly need ecological surveys. Local planning authorities routinely require a Preliminary Ecological Appraisal (PEA) as a minimum, and this often triggers further species-specific surveys for bats, great crested newts, badgers, reptiles, or nesting birds.

Survey timing is critical. Most species surveys can only be conducted during specific months of the year. Missing a survey window can delay your planning application by six months or more. Commissioning a PEA at the earliest stage of site acquisition gives you the best chance of keeping to your project timeline.

If your surveys confirm the presence of European Protected Species that will be affected by your development, you must obtain a mitigation licence from Natural England before any works that could disturb them. You cannot rely on planning permission alone - the licence is a separate legal requirement.

The licensing process requires you to demonstrate three tests: that there is no satisfactory alternative to the proposed works, that the development is in the overriding public interest, and that the species' conservation status will be maintained. Your ecologist will prepare the licence application, but you as the developer are legally responsible for compliance with its conditions.

Since February 2024, most developments in England must deliver a minimum 10% biodiversity net gain (BNG). This means the habitats on your site after development must be measurably better than before, calculated using the statutory biodiversity metric. BNG is a planning condition - you cannot discharge it without an approved biodiversity gain plan.

You have three options for delivering BNG: on-site habitat creation, off-site habitat creation on land you control, or purchasing statutory biodiversity credits from Natural England (the most expensive option). Most developers use a combination of on-site and off-site delivery.

Trees on or near your development site may be protected by Tree Preservation Orders (TPOs) or conservation area designations. Carrying out works to a protected tree without consent is a criminal offence with fines of up to 20,000 pounds in the magistrates' court or unlimited fines in the Crown Court. Even if a tree is not formally protected, felling may require a licence from the Forestry Commission.

Invasive species such as Japanese knotweed, giant hogweed, and Himalayan balsam are common on brownfield development sites. You have a legal obligation to prevent their spread, and contaminated soil must be disposed of as controlled waste. Failure to manage invasive species can also expose you to civil liability from neighbouring landowners and create problems for property transactions.

Ecological compliance does not end when construction finishes. Wildlife licence conditions typically require post-construction monitoring for several years. Biodiversity net gain habitats must be maintained for a minimum of 30 years. Tree planting conditions usually require replacement of any trees that die within five years.

Keep your ecological records, licence conditions, biodiversity gain plan, and habitat management plan accessible. These are legal documents that may be audited by Natural England or your local planning authority at any point during the maintenance period.