Ecological consultancy · England and Wales

Miss a survey window
and the scheme waits a year.

Virtus Green is an independent, science-led ecological practice. We scope early, survey in season, and write reports that hold up at determination — for housebuilders, infrastructure promoters and local planning authorities.

Survey windows — status

Optimal windows
  • Bats — emergence and re-entry surveys 1 May – 31 Aug
  • UKHab survey and condition assessment 15 Apr – 15 Sep
  • Reptiles 1 Apr – 31 May; 1 Sep – 30 Sep
  • Breeding birds 1 Apr – 30 Jun
  • Great crested newt — eDNA 15 Apr – 30 Jun

All 18 survey windows

§ 02Regulatory position

Where the rules stand today

Biodiversity net gain has moved twice this year and moves again in November. Here is the position as we read it, with dates.

In force · 6 Aug 2026

Small-site and temporary exemptions

Sites of 0.2 ha or less within the red line, and permissions granted for five years or less, are exempt from mandatory BNG — provided on-site priority habitat is not negatively affected. The self-build exemption was withdrawn at the same time, and the on-site-first hierarchy now binds only major development.

What changed, in detail
Due · 2 Nov 2026

BNG for nationally significant infrastructure

Mandatory net gain is expected to extend to English onshore NSIPs from 2 November 2026, through the Development Consent Order process. Baseline habitat condition work needs the growing season, which means the practical window for this year has already closed on most sites.

The NSIP deadline
Expected · later 2026

Statutory metric update

Defra has confirmed a programme of updates to the statutory biodiversity metric, with transitional arrangements for projects already using the current version, and a longer-term move from the Excel tools to a digital service. Watercourse elements may be taken forward separately.

All insights

Regulatory summary, not legal advice. Positions stated as at the date of the linked article; always confirm current requirements with the local planning authority.

§ 03Method

How an instruction runs

  1. Scope, before you have a scheme if possible

    A short call and a desk study tell us which surveys the site is likely to need and which windows are in play. That produces a programme and a fixed fee. This stage is free and takes about twenty minutes of your time.

  2. Survey in season, to published method

    Fieldwork to current good-practice guidance, with the method, effort and conditions recorded so a reviewing ecologist can see exactly what was done. Where we depart from guidance we say so and give the rationale in the report.

  3. Report, then peer review before it leaves

    Every deliverable is reviewed by a second senior ecologist against our internal technical standard before sign-off. This is the step that keeps reports from coming back from the local authority ecologist, and it is not optional here.

  4. Stay with it through determination and discharge

    We answer the consultee's questions, revise where the evidence supports it, hold the line where it does not, and see the ecology conditions discharged. The director who scoped the job is the one who answers the phone.

§ 04Position

Where we sit, honestly

There are three kinds of ecological consultancy you could appoint. Each is the right answer to a different problem.

Comparison of consultancy models
ModelStrongest atTrade-off
Large multi-disciplinary Integration with engineering, transport and EIA teams on very large schemes; deep bench. Higher rates, longer internal chains, the person you met at pitch is rarely the person on site.
Established mid-sized specialist Strong technical reputation, multi-office coverage, broad in-house discipline range. Capacity is tightest exactly when you need it — the peak summer survey months.
Sole practitioner Low cost, deep local knowledge, direct access to the person doing the work. No peer review, single point of failure, and no second surveyor for night work.
Virtus Green Director-led throughout, guaranteed survey slots booked ahead of the season, two-tier peer review on every deliverable. We are a small, new practice. For a multi-thousand-hectare NSIP with a twelve-discipline EIA, appoint one of the first two — and we will tell you so.
  • 1 dayTarget response to any new enquiry, in or out of season.
  • 2-tierSenior peer review on every deliverable before sign-off.
  • Class 2Natural England survey licences held for bats and great crested newt.
  • Fixed feeStandard planning deliverables quoted as a fixed price, not day rates.
§ 05Questions

Questions we get asked before appointment

My site is under 0.2 hectares. Do I still need biodiversity net gain?

Probably not, but do not assume it. Since 6 August 2026 a new exemption applies in England where the whole red-line boundary is 0.2 hectares or less — unless the development negatively affects priority habitat on site. The threshold is measured on the whole application site, not the development footprint. That priority-habitat condition is the catch: establishing whether priority habitat is present is itself an ecological judgement, and a planning officer can reasonably ask you to evidence it. A short desk study and site walkover is usually enough to settle the question, and costs a fraction of a full metric assessment.

How quickly can you get someone on site?

We aim to respond to any enquiry within one working day and to provide a fixed-fee proposal within two. Fieldwork lead time depends on the season: in the peak survey months of May to September the diary fills weeks ahead, so an early call — even before you have a scheme — is the single most useful thing you can do. Outside peak season we can usually walk a site within a week or two.

What does a preliminary ecological appraisal cost?

Fixed-fee from £1,200 plus VAT for a standard site, which covers the desk study, data search, site walkover, UK Habitat Classification mapping and a reported set of survey recommendations. A baseline statutory biodiversity metric calculation starts at £950 plus VAT. Larger or more complex sites are quoted individually, but always as a fixed fee for a defined scope — we do not issue open-ended time-and-materials quotes for standard planning deliverables.

Can you survey outside the recommended window?

Sometimes, with caveats, and it depends on which survey. Some windows are guidance and can be departed from where the ecological rationale is clear and documented — the bat guidelines say so explicitly. Others are effectively fixed: great crested newt eDNA sampling is only valid between 15 April and 30 June, and no amount of rationale changes that. Where a survey has to be done out of season, the honest answer is usually a precautionary assessment, which means assuming presence and mitigating accordingly. That can be the faster route commercially — but it should be a decision you take with the numbers in front of you, not a surprise at determination.

Who actually does the work?

A director scopes every instruction and stays named on it through to sign-off. Fieldwork is carried out by our own ecologists and, in peak season, by experienced seasonal surveyors working to our field protocols. Every deliverable is reviewed by a second senior ecologist before it is issued. Where a project needs a discipline we do not hold in house — arboriculture, or specialist freshwater work — we say so, and we bring in a named, insured specialist rather than stretching.

Tell us about the site.

Send a red-line boundary and a rough programme and we will tell you which surveys the site needs, which windows are open, and what it costs. No charge for the scoping conversation.