I bet you didn’t know that we have coral in the North Sea…

Now before you get too excited and start imaging a sprawling metropolis made of bright colours and weird structures, you might want to know a bit about our cold-water coral.

The main coral species we have here in the Northeast is Dead Mans Fingers (Alcyonium digitatum), and whilst we do occasionally see other species, this is the predominant one. Whilst Dead Mans Fingers may not resemble the wild majesty of the great barrier reef, the colours can be quite beautiful, usually oranges, whites and creams.

The name Dead Man’s Fingers is quite apt. It is named as when the coral sticks up from the substrate it does often look like a hand or fingers reaching up from the ground. It can be quite a creepy sight if you see them underwater especially if the water is dark or murky.

Coral doesn’t just look absolutely stunning, but it also has a variety of different purposes. It provides habitat for certain species, corals aid in carbon sequestration (they help to remove carbon dioxide from the atmosphere due to photosynthesis), nutrient recycling and oxygen production (again through photosynthesis from their symbiotic algae corals produce oxygen and help recycle nutrients in nutrient poor waters), the reefs that cold water corals can build help support ecosystem diversity, and corals can even play a part in coastal protection, helping to break waves before they hit the shore.

I remember the first time I saw a cold-water coral. I was on a scuba dive up the Northumberland coast; we descended beneath the surface swell and dove to 7 metres. We swam through a gulley and on either side was these odd-looking fingers reaching up to the sunlight above. It was reminiscent of a horror movie. When we got out of the water I immediately wanted to know more about these strange appendage looking animals.

Now I know that they may look like plants, but corals are in fact animals. They are marine invertebrates closely related to sea anemones and jellyfish, in the phylum Cnidaria. Corals exist as soft bodied organisms called polyps. These polyps live in colonies and create hard calcium carbonate skeletons, and that’s the part we see and admire.

Dead Mans Fingers are relatively slow growing, and it can take several years for them to reach maturity. They are quite long lived, with their colonies often surviving for over 20 to 30 years. For a coral species they are relatively small, compared to some tropical corals. They typically grow up to 10-15cm tall, although in ideal conditions they can reach 20cm in height.

We are always told that the waters around the UK and the Northumberland coast are grey and lifeless when in fact the opposite is true. Yes, some days the water is angry and grey but for many days of the year it crystal clear and beautifully blue and teaming with life and colour. The corals add the background colour for all the other life to flow around it. 

When you next venture into the wonderful North Sea, whether it be for a snorkel, dive, or just a dip, don’t forget to tell people that you are visiting the corals, I bet they won’t believe you!

@underwaterkatie