Marine life

If you take a trip to the coast and spend a short amount of time rockpooling or snorkelling, you’ll find out that Devon’s seas are full of wonder. We’ve highlighted some of the most charismatic, fascinating, and perhaps less familiar marine life that you can encounter in Devon:

Marine Mammals

Grey seal


Grey seal (pictured) – the larger and more common of the two UK seal species. It is estimated that the UK is home to more than 120,000 seals (around 40% of the world’s population), and the Southwest is a real stronghold.

Common (or harbour seal) – Despite their name, common seals are less abundant in the UK and smaller than grey seals with their face taking up a more ‘dog-like’ appearance.

Whales, Dolphins and Porpoises (Cetaceans)

There’s no better joy than spotting a pod of dolphins playing in a bay or bow-riding the wave of a boat, or even (if you are lucky) spotting a tail-fluke of a whale in the distance. What’s even better is the fact that you can do all of this in Devon – dolphins, porpoises and whales can all be spotted in our seas! Potential sightings include:

  • Common dolphinCommon dolphin  (pictured)
  • Bottlenose dolphin
  • Risso’s dolphin
  • Harbour porpoises
  • Orca (killer whale)
  • Humpback whale
  • Minke whale
  • Long-finned pilot whale


You may be familiar with the fact that we have species such as cod, bass, mackerel and pollock in our waters, but did you know that Devon is home to these fish:

Short snouted seahorse amongst kelp


Yes, Devon is home to seahorses! They can be seen amongst our amazing seagrass meadows. Both the long and short snouted seahorses can be found in Devon.


Blennies are charismatic clown-like fish. The common blenny is a likely encounter on your rockpool rambles. Did you know, just like leopards and whales, they can be recognised by their unique markings and can change colour like a chameleon.

Male cuckoo wrasse


There are several species of wrasse in our waters and they all look like they belong on a tropical reef, especially the cuckoo wrasse.



Sunfish or Mola Mola are one of the strangest sites in the ocean. Hopes Nose is a notoriously good place to spot them in the summer where they are feeding on jellyfish. You can often see them ‘flapping’ and basking on the surface.


Basking shark feeding

Sharks are fish too, they are elasmobranchs (cartilaginous fish) along with skates and rays (which we have plenty of in our waters), but we thought we would give sharks their own section because of just how awesome they are!

Many of us don’t associate Devon with sharks, but Devon is in fact home to, and visited by, many shark species, in fact over 40 species can be spotted in the UK, with at least 21 species being present in British waters all year. Below are some sharks which you could encounter in Devon:

  • Bull Huss
  • Small-spotted Catshark
  • Spurdog
  • Tope
  • Common Smooth-hound
  • Starry Smooth-hound
  • Blue Shark
  • Porbeagle Shark
  • Common Thresher Shark
  • Basking Shark (pictured)
  • Shortfin Mako

Unfortunately shark populations are declining at an alarming rate. Find out why and how you can help save our sharks



Aside from the common, but still wonderful sights of herring gulls, Devon has some very special seabirds. Perhaps the most ‘famous’ example is the puffin. Lundy island is the best place to see them, its home to 375 of them thanks to vital conservation work.

It’s not just puffins to be excited about, if you visit Berry Head from March – July you will encounter some of the 1200 breeding guillemots. Other seabirds to look out for across Devon are: razorbills, manx shearwaters, and kittiwakes.

Marine Reptiles

The waters off Devon are frequented by the largest sea turtle in the world, the leatherback turtle that can weigh up to 700kg (although sightings are rare). These ocean-going giants feed on jellyfish in our plankton rich waters.

Squid, Octopus and cuttlefish (Cephalopods)

Cuttlefish feeding

These shapeshifting, masters of disguise are wide-spread in Devon. Species include: the common octopus, common cuttlefish, common squid and little cuttlefish. They are widely regarded as the most intelligent of the invertebrates and with three hearts they have a lot of love to give!

Make sure you check out Dr Paul Naylor’s incredible footage of cuttlefish behaviour.

Other Invertebrates

Blue rayed limpets on seaweedYou can spot a plethora of other incredible marine invertebrates in Devon too. There’s far too many to name, but some of the most fascinating include:

  • crustaceans (spider crab, squat lobsters, European lobster)
  • sea stars (brittlestars, sunstars, cushion star)
  • jellyfish (moon, compass, barrel)
  • marine worms
  • anemones (snakelock, strawberry, dahlia)
  • Bivalves, such as the vibrant blue rayed limpets (pictured right)
  • corals (Devonshire cup coral and pink sea fans).

Special species

Devon is home to 96 rare and important species known as Devon Special Species. Over half of these are found within the marine and coastal environment, making them by far the most important habitats! Species include the sunset cup coral & yellow staghorn sponge. Find out more about Devon’s Special Species.

Invasive species

Invasive species are animals or plants from another region of the world that don’t belong in their new environment. They can be introduced by a variety of means, including: ballast water of ships, intentional and accidental releases of aquaculture species, aquarium specimens, and many other ways. Some of the more common and detrimental species include:

  • pacific oyster
  • carpet sea squirt
  • wireweed (or Sargassum)
  • slipper limpet
  • Chinese mitten crab

Visit the Devon Invasive Species Initiative (DISI) page to find out more.

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