Skip to Content

Marine Habitat Classification

Description of biotope or habitat type

To understand more about what this page is describing, see How to use the classification. See also How to cite.

   Atlantic upper bathyal

Physical habitat description

Salinity Full (30-35 ppt)
Wave exposure
Tidal streams
Zone Atlantic upper bathyal
Depth Band 200 - 600 m
Other Features

Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.

Distribution of habitat M.AtUB Atlantic upper bathyal

  • Records used to define the biotope (core records)
  • Other records assigned to this biotope, marked as 'certain'
  • Other records assigned to this biotope, marked as 'uncertain'
  • Predicted extent of the level 3 (for sublittoral rock & deep sea) or 4 (for sublittoral sediment) habitat

Point data based on records in the UK Marine Recorder Snapshot. Predicted habitat extent is from UKSeaMap.


Atlantic waters are warm (typically >8°C within the UK) and Atlantic seabed habitats occur around most of the UK, excluding depths greater than 300 m in the Faroe-Shetland Channel. The upper bathyal is the shallowest deep-sea zone occuring below the deep-circalittoral. Where the Atlantic upper bathyal meets the Arctic, waters mix to form the Atlanto-Arctic upper bathyal zone; here the lower boundary of the Atlantic upper bathyal zone is appoximately 300 m at the seabed, while in other areas the lower boundary is approximately 600 m, where the Atlantic mid bathyal zone begins. Communities found in this zone are described in child habitats. Biological zones are three-dimensional biogeographical regions which represent changes in biological community both spatially around the UK and vertically in relation to depth. Biological zones have some overlap in the types of community which can occur. The boundaries relate to areas of greatest change in overall species composition. The boundaries of zones are based on water mass structure which drives differences in biology. Rough boundaries of the zones have been predicted using modelled environmental data; a GIS proxy biogeographic zone layer can be downloaded from the Marine Habitat Classification download page. The depths of upper and lower boundaries depend on several variables, so the given depth range should be treated as a guide only.


No situation data available.

Temporal variation

No temporal variation data available.

Characterising species

Characterising species data not applicable.

Similar biotopes or habitat types

Not applicable or unknown.

Back to top