Important Invertebrate Areas (IIAs) are the best places in Great Britain for our invertebrates, which have been identified using the most up-to-date data available from over 80 national expert recording schemes. They support some of our rarest and most threatened species, vulnerable habitats and unique assemblages of invertebrates.
Selecting and Mapping IIAs
The criteria for IIAs were developed by a group of invertebrate, data and recording experts. The national IIA network was mapped using a wealth of data from national invertebrate recording schemes – over 45 million records from 80 schemes.
Across England, Scotland and Wales, hectads (10km x 10km squares) were identified as IIAs for either supporting one of our rarest and most threatened species, meaning there is a special responsibility to act and conserve them, or for supporting a nationally important assemblage of rare or threatened species. Species that were considered for IIA mapping were identified using these criteria: