When Local Planning Authorities Request Ecological Assessments: A Technical Overview

WHEN LOCAL PLANNING AUTHORITIES REQUEST ECOLOGICAL ASSESSMENTS: A TECHNICAL OVERVIEW

Local Planning Authorities (LPAs) in Scotland frequently request ecological assessments to support planning applications. These requests are grounded in national policy, statutory obligations, and the requirement for proportionate evidence to inform decision-making. For project managers, architects, developers, and consultants, understanding when and why ecological assessments are triggered is essential for realistic programming, accurate budgeting, and avoidance of preventable delays.

This article outlines the rationale behind LPA ecological information requests, the evidential thresholds involved, and the implications for development across Scotland.

1. Policy and legislative drivers

LPAs must ensure that planning decisions comply with the Conservation of Habitats and Species Regulations 2017 (as amended in Scotland) and the Wildlife and Countryside Act 1981, both of which impose strict protections for certain species and habitats. Planning authorities must also apply the principles of Scottish Planning Policy and the National Planning Framework, which emphasise biodiversity safeguarding and environmental risk management.

Where there is reasonable likelihood that a planning proposal may affect protected species, designated sites, or priority habitats, LPAs have a legal duty to seek adequate ecological information before issuing a decision (Scottish Government 2019; NatureScot 2020). Planning consent cannot be granted in the absence of sufficient data.

2. When LPAs are likely to request ecological assessments

LPAs commonly trigger ecological information requests when:

2.1 There is potential for protected species presence

This includes bats, otter, badger, breeding birds, water vole, and great crested newt (where relevant). Evidence may include habitat suitability, local records, or the nature of the structure affected. Even without confirmed presence, potential alone is often sufficient to require assessment.

2.2 The proposal lies within or adjacent to sensitive habitats

Woodlands, wetlands, riparian corridors, peatlands, and species-rich grasslands frequently prompt assessment requests due to their ecological importance and policy status.

2.3 The proposal affects structures commonly used by protected species

Buildings with crevices, bridges, culverts, stone walls, and mature trees routinely attract requests for bat surveys.

2.4 Insufficient baseline information accompanies the application

Where Preliminary Ecological Appraisals (PEAs) or other early-stage assessments are missing, incomplete, or inadequately evidenced, LPAs will request further information to determine ecological relevance.

3. Proportionality and the Scottish approach

LPAs are expected to follow a proportionate approach to ecological information, consistent with NatureScot guidance. This means:

• Surveys must be appropriate to the scale and risk of the proposal.

• Applicants should not be required to survey for species with no reasonable likelihood of being present.

• High-risk features require higher survey effort, while low-risk proposals may need only basic screening.

Proportionality does not mean minimal effort; rather, it ensures that evidence matches ecological risk, enabling defensible planning decisions.

4. Common triggers for bat-specific assessments

Because bats are European Protected Species, LPAs often adopt a precautionary approach. Triggers include:

• modification, replacement, or demolition of buildings with bat roost potential;

• works to bridges, culverts, or stone structures;

• lighting schemes affecting known or potential roosts;

• woodland removal or tree works involving mature or veteran trees.

Where roost potential is identified, LPAs expect evidence from seasonally appropriate surveys, not general inspections, to inform decision-making (BCT 2023).

5. Planning validation vs. planning determination

A crucial distinction exists between:

5.1 Validation requirements

LPAs may validate an application with minimal ecological information, provided that an initial assessment (such as a PEA) is submitted. Validation does not mean the application contains adequate information for approval.

5.2 Determination requirements

During determination, LPAs must ensure they have all information needed to make a lawful decision. This often requires further surveys, additional analysis, or a detailed mitigation strategy. If this information is not available within statutory timeframes, LPAs may:

• request more information;

• defer determination;

• or refuse the application based on insufficient evidence.

Understanding this distinction prevents unrealistic expectations during project planning.

6. Why late ecological requests occur

Late requests for ecological information are usually driven by one of the following:

• ecological constraints not identified early enough;

• incomplete or outdated survey data;

• seasonal limitations preventing required survey work;

• design changes increasing ecological risk;

• insufficient detail in planning submissions.

These issues commonly arise when ecological input is sought late in the design process, leaving little time for proportionate surveys.

7. Reducing risk through early engagement

Early ecological involvement enables:

• identification of species likely to trigger surveys;

• survey programming aligned with species survey windows;

• clear understanding of mitigation requirements;

• alignment between ecological outcomes and planning conditions;

• informed dialogue with LPAs and NatureScot where necessary.

Projects that delay ecological engagement frequently encounter seasonal survey constraints, leading to deferral to the following survey year.

Conclusion

Ecological assessments requested by Local Planning Authorities are driven by legal requirement, policy expectation, and proportional risk assessment. Understanding when and why LPAs request information helps project teams anticipate constraints, design realistic programmes, and avoid preventable delay. Early ecological screening and clear communication with planning authorities remain the most effective ways to ensure legally robust and proportionate planning submissions in Scotland.

References

Bat Conservation Trust 2023. Bat Surveys for Professional Ecologists: Good Practice Guidelines. Bat Conservation Trust, London.
NatureScot 2020. Guidance for Local Authorities on Protected Species and Planning. NatureScot, Inverness.
Scottish Government 2019. Wildlife Crime and Protected Species. Scottish Government, Edinburgh.
Scottish Government 2020. Planning Guidance on Biodiversity and Protected Species. Scottish Government, Edinburgh.