Celtic Deep recommended Marine Conservation Zone

Status: Potential T3 site

Common dolphins (Credit Eleanor Stone, Manx Wildlife Trust)Common dolphins (Credit Eleanor Stone, Manx Wildlife Trust)

Celtic Deep is an important aggregation area for seabirds and common dolphins.

The area is particularly important for its deep water mud habitats, which are rare for this region.

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The southern tip of the Celtic Deep is 112km north-west of Trevose Head and the western tip is 84km from the Pembrokeshire coast in Wales.

Important frontal systems occur here during summer indicating its value as an area of high productivity, which is supported by the recording of large aggregations of copepods. Copepods are essential for the health of the marine food web and contribute to the diet of the second largest fish in the world, the basking shark.

Celtic Deep is an important aggregation area for seabirds and common dolphins. One of the largest ever known gatherings of fin whales in British waters was recently observed here!

Intense levels of human activity within the site has resulted in Celtic Deep being classified as at risk by Natural England and the Joint Nature Conservation Committee- there is a high risk that the habitats and species found in this site are currently damaged or deteriorated.

Although proposed for designation in the 2013 Defra consultation, this site is now on hold. The proposal to designate this site will be reviewed in light of further developments in the devolution of UK waters. We will continue to reinforce the need for an ecologically coherent network of Marine Protected Areas, which includes the need for sites to be designated in Welsh Offshore waters.


Contains UKHO Law of the Sea data. Crown copyright and database right and
contains Ordnance Survey Data Crown copyright and database 2012


Other nearby sites

East of Celtic Deep  South of Celtic Deep


FilenameFile size
Celtic Deep Factsheet.pdf2.92 MB