We utilse the expertise of specialist sub-contractors for our invertebrate surveys due to the large number of species across each group.
- 1. Background
- 2. What to survey for
- 3. Aquatic Survey
- 4. Terrestrial Survey
- 5. Mitigation
There are few legally protected invertebrates in the UK, however a large number are highlighted on the UK Biodiversity Action Plan (2007) including many associated with brownfield development sites. For this reason they are of principle importance for any site survey.
Whilst there are a large number of UKBAP species and that alone is reason for survey, invertebrates are also valuable habitat indicators. They can help assess whether an area of land is “good quality” or of low biodiversity value because they occupy every tiny permutation in a habitat (a niche). For each niche there can be species of invertebrate that are of conservation importance or there will be indicators of particular features such as deadwood, cut plant stems, partially inundated ground, mobile sands or complex mosaics of herb-rich grassland and bare ground.
By carefully selecting the groups of invertebrates to sample (such as hoverflies, bees and wasps, butterflies) specialist surveyors can robustly assess a site for its invertebrate potential by targeting invertebrate groups applicable to the habitats present at the site.
In this way the most effective use of time and resources can be given to fairly and accurately assess a site for its invertebrate potential. New methods for survey including nationally recognised guidelines for targeting the most appropriate groups are now available. Along with these guidelines is a new software application to help assess sites of importance.
Water beetles are useful habitat indicators and also important insects with many scarce species including the legally protected lesser silver water beetle Hydrochara caraboides.
The most important types of water bodies are ephemeral or season pools which are often found on urban development sites and in quarries.
Whether it is a woodland, grassland, brownfield site, quarry or coastal dune there are particular groups of invertebrates that are of importance and fidelity to that type of habitat. Key groups that are often required for assessment include butterflies, moths, bees and wasps, various fly families and also beetles.
Invertebrates are not the most visible group of animals that we share our lives with. Otters, water voles and great crested newts are more tangible animals that people understand. Invertebrates, though small, require as much protection as larger animals.
Mitigation can be straightforward and tied into schemes for other species such as great crested newts which often share the same habitats as many scarce invertebrates on brownfield sites. Very basically, invertebrates need a place to breed and a place to feed. This can be accommodated for in relatively small areas, as long as mitigation is designed well and because many key insects are flower feeding species, migration can be aesthetically pleasing to people as well as a functional resource for the insects.