The first major update in over 15 years of the common language that describes life on the seafloor has been published. The Marine Habitat Classification for Britain and Ireland (MHCBI) is used for Protected Area designation, assessments of environmental status, marine spatial planning and casework throughout the UK.

A report in JNCC’s latest newsletter says that a collaborative effort by JNCC and the marine community has updated the sedimentary section of the classification, which describes areas of the seabed that are not rocky, adding a set of five new habitats and expanding the definitions of others.

Two epifaunal habitats (with animals living on the seabed) were determined from underwater video data. One, discovered in the Small Isles off north-west Scotland, is a habitat dominated by fan mussels and brittlestars which also supports a diverse array of anemones, crustaceans and sea urchins. The other is dense Ophiura brittlestar beds which are widespread throughout the UK – a habitat known for some time but now recognised in the classification.

Three new infaunal habitats (with animals living in the seabed) were determined from Day grab data. One is a muddy habitat supporting the crustacean Calocaris macandreae and a variety of polychaete worms. The second is a mixed sediment community found in the English Channel and the third was discovered on sandbanks to the East of the Isle of Man. Access to new survey data has improved definitions of 26 existing habitats, for example expanding definitions where a community has been found on different sediment types.

JNCC have also updated 22 species names throughout the classification. Now work is analysing the sediment habitats on the shore, and rock habitats.

For further information see the Marine Habitat Classification for Britain and Ireland’ website here.