Ecology and Natural Environment

Our expert ecologists help clients navigate the complex ecological and regulatory landscape to ensure sustainable development. From initial site assessments to post-construction monitoring, we provide end-to-end support that combines robust science with practical, integrated design solutions.

We work across all sectors, supporting planning, permitting, and construction through proactive ecological advice, survey delivery, mitigation design, and compliance services. With a deep understanding of UK and European legislation and international best practice, we help clients build with biodiversity in mind.

Ecological Assessment and Reporting

Our experts are skilled at the ecological assessments of local, regional, and national policy. We bring decades of experience providing assessment and reporting services for important infrastructure projects that deliver on economic, social, and environmental needs whilst protecting and restoring biodiversity.

• Preliminary ecological appraisals (PEA)
• Ecological impact assessments (EcIA) and specialist environmental impact assessment (EIA) chapters
• Habitats directive and habitat regulation assessments of plans and projects
• Habitats regulation assessment (HRA), Appropriate Assessment (AA) screening, Natura Impact Statement (NIS), Article 6(4)/Alternatives & Compensation Assessments
• Biodiversity inputs to strategic environmental assessment (SEA) of plans and projects
• Water Framework Directive (WFD) assessments
• Licence applications including species and maritime usage license (MUL)

Habitat Survey and Assessment

We provide comprehensive assessments to understand ecological constraints and opportunities from the outset of a project.

• Terrestrial habitat mapping and classification surveys (Phase 1, UKHabs, NVC, Fossitt, IVC, Annex 1 Habitats)
• Freshwater habitat mapping, characterisation and bioassessment surveys (Q-value, RHAT, River Condition Assessment (RCA), River Habitat Survey (RHS))
• Marine habitat mapping and classification surveys (benthic, coastal, and intertidal)
• Habitat suitability and condition assessments
• Biodiversity Net Gain (BNG) strategy, planning, and advice

Species Survey and Assessment

Our specialists deliver a full suite of protected and notable species surveys, tailored to seasonal and legislative requirements.

• Bats (roost assessment and characterisation—trees, buildings and structures; tree climbing, emergence surveys, activity surveys—transect, static and bioacoustics, hibernation assessment, offshore activity)
• Otters (presence/likely absence, trail camera, holt/couch characterisation)
• Badgers (presence/likely absence, trail camera, sett characterisation, bait marking studies)
• Other mammals (dormice, water vole, red squirrel, pine marten, deer)
• Amphibian and reptile (presence/likely absence, great crested newts, eDNA)
• Ornithology (breeding bird, raptor, wintering birds, vantage point, bioacoustics, marine, coastal)
• Freshwater aquatic species (electrofishing, eDNA, crayfish, pearl mussel, lamprey, salmonids, macrophyte, diatom)
• Protected plants (Flora Protection Order)
• Invertebrate (marsh fritillary, butterflies, moths, aquatic invertebrates)
• Invasive species (Japanese knotweed, invasive plants, invasive animals)

Licensing and Mitigation

We support clients in obtaining licences and designing pragmatic mitigation strategies to keep projects moving. Our approach integrates mitigation hierachy into all stages of project design including constraints analysis, optioneering, multi-criteria analysis, avoidance, and impact minimisation. Our Natural England Class Mitigation Licences include Bat Earned Recognition, GCN District Level Licensing, and other specialist species licencing routes.

• Species mitigation/derogation licences and compensation
• Mitigation strategy design and implementation
• Monitoring and post-development reporting
• Marine consenting (MUL, maritime area consent (MAC))

Arboriculture

Our qualified arboriculturists support clients to meet their goals in alignment with the European Union’s Nature Restoration Regulation. Our experts provide tree surveys, arboricultural advice, and expert witness services to support the integration of development around trees to protect the natural environment, and to ensure trees are managed to their potential within their environment.

• Trees and Development
  • BS 5837 Tree Surveys (with reports and schedule) and Tree Constraints Plans (TCP)
  • Arboricultural Impact Assessments (AIA) and Tree Retention and Removal Plans
  • Arboricultural Method Statements (AMS) and Tree Protection Plans (TPP)
  • Arboricultural Clerk of Works
• Trees and People
  • Tree health and safety assessments for risk (THREATS, QTRA, VALID)
  • Veteran tree and ancient tree and woodland assessments
  • Tree risk management policies, tree strategies and woodland management
  • Canopy cover and carbon capture/sequestration assessments
• Trees and Law
  • Tree preservation orders (TPO), conservation areas
  • Forestry Act (Felling Licences) and woodland management
  • TPOs and planning applications/consents
  • Tree valuation (CAVAT, Helliwell)

Nature by Design

Tetra Tech’s ecological experts bring a global suite of knowledge, experience, and capabilities to plan, design, and deliver resilient solutions for people and nature. We help quantify, value, and enhance natural systems to deliver long-term environmental and social benefits. Working alongside our engineers, we integrate ecology with landscape architecture to deliver multifunctional spaces that deliver ecosystem services to support our economic, social, and environmental needs while protecting and restoring nature.

• Natural capital assessments and baseline studies
• Ecosystem service valuation and mapping
• Nature based solutions (NbS) and nature inclusive design (NID)
• Integration with BNG and ESG strategies including biodiversity CSRD strategies and reporting
• Stakeholder engagement and benefits visualisation
• Planning, design, and implementation of green and blue infrastructure
• Habitat creation and restoration
• Urban greening and pollinator strategies
• Integration with sustainable drainage systems (SuDS)

Ecological Clerk of Works (ECoW)

We provide on-site ecological supervision to reduce risks and ensure legal compliance during construction.

• Toolbox talks and site inductions
• Watching briefs, ecological monitoring, and action logs
• Habitat protection and translocation advice
• On-site stakeholder liaison and reporting
• Detailed ecological construction method statements