Phase I Habitat Survey

If you are proposing to develop a site, it is usually a requirement to provide ecological information as part of a planning application and without it, your application may not be validated. The Local Planning Authority (LPA) may ask you if a ‘Phase I Habitat Survey’ has been carried out.

The Phase I Habitat Survey technique is a widely used and standardised system devised by the Joint Nature Conservation Committee (JNCC) which is used by ecologists for classifying and mapping wildlife habitats across Great Britain. The main purpose of the survey is to identify what habitats are present and if they are of nature conservation importance.

During a Phase I Habitat Survey, vegetation is mapped and assigned to a category. Target notes are used to refer to features of particular interest or for habitats which are too small to map. There are ten broad level categories (as listed below) which are further divided into a range of specific habitat types:

  • Woodland and scrub 
  • Grassland and marsh
  • Tall herb and fen
  • Heathland
  • Mire
  • Swamp, marginal and inundation
  • Open water
  • Coastland
  • Exposure and waste
  • Miscellaneous

For the purposes of development, the scope of the Phase I Habitat Survey is usually widened and an ‘Extended Phase I Habitat Survey’ is carried out whereby additional information is collected. E.g. information on habitat composition including plant species present and their abundance, habitat condition and management measures if evident. In addition, an assessment of habitats to support protected or priority/notable species is usually carried out and a search for signs of non-native invasive species may be included. 

Protected species are those to which legal protection is afforded. Certain species are also of nature conservation importance because they are rare/vulnerable or in decline, these are often referred to as ‘priority’ or ‘notable’ species. Non-native invasive species are those that have spread into the wild at the detriment of our native habitats. It is illegal to cause the spread of certain non-native species in the wild, therefore if they are present on a site their management and removal is an important consideration.

The Extended Phase I habitat survey is usually the first ecological survey carried out on a site and together with a desk study forms what is commonly referred to as a ‘Preliminary Ecological Assessment’ (PEA).

The desk study element of the PEA involves an online search to:

  1. Identify records of protected and priority/notable species on, or in the locality of a site.
  2. To ascertain the presence of any nearby designated sites or priority habitats.

In the majority of cases, it is also necessary to contact the Local Environmental Records Centre (LERC) for more comprehensive information not freely available online. There are costs associated with the retrieval of records from records centres.

Protected species are those to which legal protection is afforded. Certain habitats and species are also of nature conservation importance because they are rare/vulnerable or in decline, these are often referred to as ‘priority’ or ‘notable’ habitats/species.

Statutory designated sites are those which are protected under current UK/European legislation and include Sites of Special Scientific Interest (SSSI), National Nature Reserves (NNR), Special Areas of Conservation (SAC), Special Protection Areas (SPA), Ramsar Sites and Local Nature Reserves (LNR). Sites that are classified as non-statutory are typically known as County Wildlife Sites (CWS). They are designated on account of the flora and fauna they support and are considered to be of county wildlife importance.

It is important to carry out a desk study to build an initial picture of ecology on a site. For example, it can quickly be determined if a SSSI occurs adjacent to or in close proximity or if a protected species occurs on site or close by. An absence of information for a site however, does not necessarily mean that there are no ecological considerations, hence why an Extended Phase I Habitat survey by an experienced ecologist is also required.

Once complete the results are collated into a report, commonly referred to as a ‘Phase I Survey Report’ or ‘Preliminary Ecological Assessment Report’ (PEAR) where the following is highlighted:

  • Potential ecological constraints
  • Whether further ecological surveys are required prior to your planning submission
  • Any mitigation measures necessary (although it may not be possible to determine all of these until further survey work is completed)
  • Opportunities for ecological enhancements.

As well as written text, the report usually includes a habitat map, photographs and where appropriate, an ecological constraints and opportunities plan may be included.

It is important to note that if the Phase I report/PEAR recommends that further ecological survey work is required, surveys must be completed and appropriate mitigation measures formulated before the local planning authority will consider any planning application. In such circumstances a Phase I report or PEAR on its own is insufficient and the Local Planning Authority will require a more detailed report which incorporates the results of further surveys together with an assessment of ecological impacts and mitigation/enhancement measures. Such a report is usually referred to as an ‘Ecological Impact Assessment’.

Surveys for protected species are generally constrained to the warmer months as many animals are inactive during the winter. Therefore, if a site walkover is carried out in the winter months and it is determined that habitats have the potential to support a protected species, it may not be possible to carry these out until the following spring/summer.

The main purpose of a Phase I report/PEAR is to inform a developer and their design team about the key ecological constraints and opportunities associated with a project. Commissioning an ecological consultant to produce a Phase I report/PEAR at an early stage means that any further surveys required can be inputted into project programmes and mitigation and enhancement measures can be incorporated into the design rather than retrospectively. This reduces the risk of delays and makes for a much smoother process leading up to planning.

Whether you are an individual homeowner, a developer looking to submit a planning application or if you are a member of the project team such as an architect, planning consultant, or landscape architect and require further information on Phase I Habitat Surveys, one of our experienced ecological consultants at Burton Reid will be happy to help.

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