Invertebrate organisms comprise a vast range of species fulfilling many fundamental roles in ecosystem services provision – there are approximately 30,000 species in the UK. Invertebrates include familiar animals such as dragonflies, beetles, earthworms, spiders, molluscs, flies, butterflies and moths but also less well-known varieties such as tardigrades, isopods and freshwater mussels.
Invertebrates are present in every habitat, they are strong indicators of environmental quality, often occurring in unique, local assemblages and many are incredibly rare, relying on the conditions specific to their niche, such as a particular plant variety.
They directly fulfil numerous vital ecosystem functions including pollination and decay and are a vital food source for many animals higher up the food chain such as amphibians, birds and reptiles.
Despite their diminuitive individual size, we must acknowledge that invertebrates are capable of causing major damage to structures (termites), natural capital assets (Oak Processionary Moth) and natural ecosystems and agricultural production systems as well as causing disruption to development. In addition, there are increasing numbers of invasive non-native species such as the Asian Hornet and Signal Crayfish.
Many species are rare, endangered or vulnerable and have protected status. Whilst there are only three designated European Protected Species, there are about 400 other invertebrate species of Principal Importance in England that need to be taken into account in planning decisions covered by:
- The Wildlife and Countryside Act 1981, Schedule 5
- S41 Priority species protected through biodiversity policy
Middlemarch Environmental ecologists routinely survey all terrestrial and freshwater habitats for invertebrates using a variety of standard techniques, such as the Freshwater Habitats Trust’s ‘Predictive System for Multimetrics (PSYM)’ methodology. We undertake invertebrate surveys for two primary reasons, firstly when development plans may affect habitats that are notable for their invertebrate population and secondly when we want to evaluate habitat condition, for example in undertaking biodiversity net gain assessment. We can advise on both risks to development plans from invertebrate species and design and create habitat to encourage their presence and enrich biodiversity. Invertebrate Surveys may be undertaken to support:
- Site selection (eg as local reserves,SSSIs)
- Impact assessment and mitigation
- Assessments at a landscape or regional scale
- Species recovery and action plans
- Management advice; and
- Change monitoring