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https://defraenvironment.blog.gov.uk/2023/10/05/irreplaceable-habitats-and-bng-what-you-need-to-know/

Irreplaceable habitats and BNG: what you need to know

Posted by: , Posted on: - Categories: Biodiversity net gain, Land use
Ancient Mighty Oak Tree with Exposed Tangled Roots. Source: Getty

Ahead of mandatory BNG, we are confirming that the initial list of irreplaceable habitats for biodiversity net gain (BNG) purposes will broadly mirror the list of examples already within the National Planning Policy Framework. This will be followed by a consultation next year so that we can incorporate learnings from the initial months of BNG into the final irreplaceable habitats list.

How irreplaceable habitats interact with BNG

The irreplaceable habitats list recognises and protects England’s most valuable habitats. They have a high biodiversity value and are so difficult to recreate, that it would be impossible to achieve the requirement to increase biodiversity on top of no net loss.

Irreplaceable habitats have significant protection in the National Planning Policy Framework. Impacts on these habitats from development require a strong justification. BNG will strengthen these protections further.

For BNG purposes, the 10% net gain requirement is not applied to irreplaceable habitats, as they are so valuable, they cannot be easily recreated.

Irreplaceable habitats must still be recorded in the biodiversity metric, but any impacts to these habitats will flag as unacceptable and requiring bespoke compensation to be agreed with the planning authority.  If there are no impacts, enhancement of irreplaceable habitats can contribute to towards a developments BNG requirement.

The BNG irreplaceable habitats list

The below irreplaceable habitats are an initial list, to support the launch of mandatory BNG, ahead of a public consultation on a broader definition of irreplaceable habitat in 2024.

For now, in mandatory BNG, the list of habitats will be:

  • Ancient woodland
  • Ancient and veteran trees
  • Blanket bog
  • Limestone pavements
  • Coastal sand dunes
  • Spartina saltmarsh swards
  • Mediterranean saltmarsh scrub
  • Lowland fens

This list will be set out in secondary legislation and because it is a list already in use, provides certainty for developers and local planning authorities during the first phase of implementation of BNG whilst they are adjusting to the new mandatory requirement.

Future consultation on irreplaceable habitats

We will launch a public consultation on irreplaceable habitat in the second half of 2024. The consultation will seek views on the definition and list of irreplaceable habitats. The consultation will seek views related to BNG, but also the impact of any new definition or list on wider planning policy.

What developers need to know

Mandatory biodiversity net gain will not change the existing strong protections and compensation requirements for these habitats already required in planning policy.

If you’re a developer, you should consider if these habitats are present on any of your sites and speak to your local authority at an early stage if they will be affected.

If you have been granted planning permission on a site with irreplaceable habitat present, you should firstly try to minimise any impacts on those habitats. Where this isn’t possible and there is a loss of irreplaceable habitat as a result of the development, these habitats will be excluded from your BNG calculation as the habitats are so valuable, it could be impossible for you to meet the BNG requirement. Instead, you’ll need to agree bespoke compensation with your local planning authority as part of the planning application process.

If you’re retaining or enhancing any irreplaceable on your site (which we encourage you to do), you should record this in your metric calculations. Any enhancements to irreplaceable habitat should be recorded in the metric and can count towards your 10% BNG.

You’ll still need to achieve 10% BNG on any other non-irreplaceable habitat present on your development site.

Compensating for irreplaceable habitats

Where impact to irreplaceable habitat cannot be avoided, developers will be required to deliver bespoke compensation agreed with local planning authorities on a case-by-case basis. The planning authority must be satisfied that as a minimum, the compensation plan meets requirements in relevant policy and guidance and delivers appropriate compensation which should aim to reflect the same type of habitat that was lost.

The legislation will also set out that off-site biodiversity units and statutory biodiversity credits cannot be used to compensate for the loss of irreplaceable habitat.

Varieties of saltmarsh

The National Planning Policy Framework lists a single broad category of ‘salt marsh’, but following the latest ecological evidence, we will list ‘Spartina saltmarsh swards’ and ‘Mediterranean saltmarsh scrub’ as irreplaceable for BNG purposes as these two categories of saltmarsh only are very rare and irreplaceable outside their natural range in the south and southeast of England. Other types of salt marsh habitat are considered replaceable, so we do not want to exempt these habitats from the 10% BNG condition.

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11 comments

  1. Comment by SIMON HARDING posted on

    I cannot believe Ancient Grassland habitats with their unique botanical and mycological assemblage have been omitted from the list of irreplaceable habitats.
    These are habitats no amount of money can recreate, when they are gone they are gone forever and are suffering huge decline from well intentioned but poorly researched change of land management including well financed Tree planting, Change of Agricultural use and Developments are seriously impacting on their quality and quantity yet we know they are important sites that contain many species vulnerable to extinction in the wild.
    Please, I strongly urge you to reconsider and include Ancient Grasslands as irreplaceable habitats before we lose them

    Reply
    • Replies to SIMON HARDING>

      Comment by pollywight posted on

      Hi Simon,
      Thank you for your comment. I've spoken with the relevant team. They've told me that irreplaceable habitats already have significant protection in the National Planning Policy Framework. Impacts on these habitats from development require a strong justification. BNG will strengthen these protections further. We have confirmed that the initial list of irreplaceable habitats for BNG purposes will broadly mirror the list of examples already within the National Planning Policy Framework.
      There will be a public consultation on the definition of irreplaceable habitats in 2024 so we can incorporate learnings from the initial months of BNG into the final irreplaceable habitats list. The consultation will seek views related to Biodiversity Net Gain, but also on the impact of any new definition or list on wider planning policy.
      I hope this helps to answer your question!
      Polly
      Blog team

      Reply
  2. Comment by Cherry Beeby posted on

    We have to protect the eco systems, this include all forms of native flora and fauna including in my opinion fungi species. They are the green flags of a healthy eco system and should not be ignored

    Reply
    • Replies to Cherry Beeby>

      Comment by pollywight posted on

      Hi Cherry,
      Thanks for your comment. I've recently replied to Simon, who left a similar comment on this post. Please see the response to Simon's comment for more information. I hope this helps!
      Polly
      Blog team

      Reply
  3. Comment by Philip Wilson posted on

    I am very concerned that other Priority Habitats (NERC Act 2006) are not included in the list of irreplaceable habitats. The full biodiversity of species-rich grasslands, lowland heathlands and other habitats cannot be recreated within the medium-term, and given the rarity of these habitats, their value for biodiversity and importance for other ecosystem services (especially carbon-storage), I would strongly urge that they be included in the irreplacable habitat list and regarded as such in the BNG system.

    Reply
    • Replies to Philip Wilson>

      Comment by pollywight posted on

      Hi Philip,
      Thanks for leaving us a comment. Please see my response to Simon's comment on this post, which I feel addresses your comment also. I hope this is useful!
      Polly
      Blog team

      Reply
  4. Comment by Carol Fisk posted on

    Hello. Your reply didn’t directly answer the question about adding grasslands to the list. Can you confirm, as you suggest, that they are already protected in the same way as the 8 listed irreplaceable habitats? Thanks

    Reply
    • Replies to Carol Fisk>

      Comment by pollywight posted on

      Hi Carol,
      I've spoken to the relevant team and they've provided me with the following definition for Irreplaceable Habitats.

      Irreplaceable habitats are defined in the National Planning Policy Framework as habitats which would be technically very difficult (or take a very significant time) to restore, recreate or replace once destroyed, taking into account their age, uniqueness, species diversity or rarity. They include ancient woodland, ancient and veteran trees, blanket bog, limestone pavement, sand dunes, salt marsh and lowland fen. As we’ve confirmed, the list for BNG purpose broadly mirrors this list and will be subject to a public consultation later in the year.

      I hope this helps!
      Polly
      Blog team

      Reply
      • Replies to pollywight>

        Comment by Carol Fisk posted on

        Hello. It's the same issue. There is no mention of grasslands, some of which are indeed technically very difficult (or take a very significant time) to restore, recreate or replace once destroyed. Acid grasslands, which are rare where I live, are currently at risk and we would welcome more solid inclusion for habitats like that in both the irreplaceable habitats list and BNG.

        Carol

        Reply
  5. Comment by Elizabeth Brandon-Jones posted on

    Dear Polly,

    When carrying out field work in order to fully understand a landscape its often necessary to map the significant semi-natural habitats to NVC standard, It would be very helpful if you could provide a higher level of detail ie to NVC level. Please can you provide a compatibility list &/or spreadsheet showing the relationship between
    *Habitats of Principal Importance,
    *BAP habitats
    *European Red List habitats
    *National Planning Policy Framework as habitats
    *Irreplaceable habitats
    I hope this information will show why some habitats of significance such as grasslands (neutral, calcarious, and marshy) appear to have been missed off the BNG Irreplaceable habs list. Also why is Mediterranean saltmarsh scrub included?
    Ancient woodland
    Ancient and veteran trees
    Blanket bog
    Limestone pavements
    Coastal sand dunes
    Spartina saltmarsh swards
    Mediterranean saltmarsh scrub
    Lowland fens

    Look forward to hearing your response (please can you email your reply as I am not sure if I will be able to find this webpage again)
    thanks Liz
    Thanks

    Reply
    • Replies to Elizabeth Brandon-Jones>

      Comment by pollywight posted on

      Hi Liz,

      Thank you for your comment! Our BNG team have said that they will be consulting on the list of irreplaceable habitats for BNG later this year and will welcome and take into account any evidence on specific habitats that is submitted.

      I hope this helps!

      Thanks,
      Polly
      Blog team

      Reply

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