The coasts of UK and Ireland are very important for breeding seabirds. The latest survey found that around 8 million sea birds from 25 different species breed in these two islands. This includes globally significant breeding populations of certain species, such as 90% of the world's Manx Shearwater. 18 species regularly breed in Northern Ireland. In addition to those breeding along Northern Ireland's coast, there are species that visit Northern Ireland during their annual migration, and those that feed in our seas.

Species include:

Northern Fulmar, Manx Shearwater, Common Shag, Great Cormorant, Black Headed Gull, Common Gull, Lesser Black-Backed Gull, Great Black-Backed Gull, Herring Gull, Black Legged Kittiwake, Sandwich Tern, Roseate Tern, Common Terns, Arctic Tern, Common Guillemot, Black Guillemot, Razorbill, Atlantic Puffin, Gannet, Great Skua, Arctic Skua, Oystercatcher, Brent Goose, Ringed Plover.

Northern Ireland has two species of seals and 24 species of cetacean (whales, dolphins & porpoises)  have been recorded in Irish waters, with 8 species regular visitors or residents to our shores.

Seals

Both the grey seal and the common (harbour) seal are year round residents on Northern Ireland's coast. The Grey Seal is the larger of the two, and adult males grow up to 2.5m. New pups are born between September-December. The grey seal is one of the rarest seals in the world, and the coasts around the UK support approximatel 40% of the global population. Some good spots for viewing the grey seal is the Maidens (off Larne), the Copelands (off Bangor) and Rathlin Island.

The common seal or harbour seal, is smaller in size, with adult males growing up to 1.8m. They have pups in summer, in June/July. They are easily seen in Strangford Lough.

The Exploris Aquarium in Portaferry also hosts a seal sanctuary for orphaned seal pups.

Cetaceans (whales, dolphins, porpoises)

There are at least 24 species of cetacean (whales, dolphins & porpoises)  which have been recorded in Irish waters, with 6 species regular visitors or residents to our shores. This includes , minke whale, bottlenose dolphin, common dolphin, risso's dolphin, orca (killer whales), & harbour porpoise. Less regular visitors include humpback whale, fin whale, sperm whale, Atlantic white-sided dolphin. Not all of these species are likely to be seen from land, with some species preferring deeper offshore waters. You are most likely to catch a glimpse of a bottlenose dolphin or harbour porpoise (the smallest of the cetaceans) along the North Coast of Northern Ireland, the Skerries and the Causeway Coast. Clike here if you want to hear what a harbour porpoise sounds like, or visit Voices in the Sea to hear other cetacean species calls. You can read more about the cetaceans found around our coasts from our partner organisation the Irish Whale and Dolphin Group.

This large grouping of animals includes the sub groups of ray-finned fish, and cartilaginous fish (sharks & rays), as well as jawless fish, and lobe finned fish.   

Ray finned fish

There are many different species in this group, in fact they total half the number on known vertebrate species on this planet. Most fish are part of this group, including commercially important species. These fish use gills to breath and most are 'cold-blooded' which means that they rely on the water temperature to heat and regulate their body temperatures. In Northern Ireland there are many different species of fish including wrasse, cod, whiting, plaice, flatfish, turbot, mackerel, haddock, herring, dogfish, coalfish, pollack, flounder and conger eels.  

Sharks and Rays (Cartilaginous fish)

This group of fish have skeletons made out of cartilage rathern than bone. Sharks evolved between 450-420 million years ago. Around the UK and Ireland there are atleast 30 species of shark, with 21 species year round residents or regular visitors. Northern Ireland has at least eleven species of shark which are regularly found around our coast. Around the world many shark species are severley depleted in number, affected by overfishing (directly, and of their prey) and as by-catch, with human development of the sea another likely disturbance. 

One iconic shark species for the UK includes the basking shark, which is the second largest fish in the world, after the whale shark. It can grow up to 12m, however it feeds on some of the smallest marine animals- plankton. These amazing animals migrate large distances, and are found around the planet, outside of the polar regions. In Northern Ireland they can be seen along the coast during summer, as they feed in the waters during their trans-Atlantic migration. They are listed as a Northern Ireland Priorty Species and are protected in our seas. Simon Berrow from our partner organisation, the Irish Whale and Dolphin Group, is involved in studying the Basking Shark in the North-East Atlantic. You can find out more from his recent Ted Talk. You can also read more about sharks in UK and Irish waters from the Shark Trust website. The Northern Ireland Environment Agency and the Agri-Food and Biosciences Institute have also produced a summary document outlining current knowledge of sharks, skates and rays in Northern Ireland. Read about the UK's committment to protect endangered sharks under the Convention of Biological Diversity and the European Parliament's 2012 vote to end the practice of shark finning.

Skates and Rays are the sister group to sharks. There are over 500 species of skate and ray in the world. There are 6 species recorded for Northern Ireland, including the common skate, thornback ray, blonde ray, cuckoo ray, white skate and undulate ray. Most species are now rarely found in Northern Ireland's seas. The common skate was once abundant, but is now believed to be almost locally extinct from the Celtic Seas region of the UK and Ireland. There has also been recent work to suggest that the common skate is in fact two different species, see the Orkney Skate Trust for more information.

If you would like to be involved in work to help conserve the species of sharks and rays found in the UK and Irish seas, then you can take part in the Shark Trust's Great Eggcase Hunt project.

The fish on the Northern Ireland Priorty Species List can be found here.

Crustaceans

Crustaceans are animals with a hard outer covering called an 'exoskeleton' on the outside of their body. They have soft bodies with no bones on the inside. These exoskeletons must be periodically shed (the moult) and re-grown to allow the animal to grow.  Their bodies are divided into distinct segments. Animals in this group include sea lice, crabs, lobsters, shrimp, krill and barnacles. The life cycle begins with fertilised eggs developing into various larval forms, which then grow into adult forms of the animal. In Northern Ireland, the lobster, brown and velvet crabs are important species for fishing. The Dublin Bay prawn, or nephrops/langoustine/scampi is also important to our local fishing industry, and is a major export to France and the Netherlands and other countries in mainland Europe. It is not a prawn, but actually a type of small lobster.

Echinoderms

The latin word 'echinoderm' means 'spiny skinned'. This group includes starfish, brittle sea stars, sea cucumbers, sea urchins and feather stars. All the species in this group are marine. Their bodies are divided into five equal parts, such as star fish which have at least five arms 'radiating' from the centre of their body. They do not have brains, eyes, or hearts. They have 'tube feet' which have tentacles functioning as suction pads, this allows them to attach to the sea-bottom or to rocks in rock pools. 

Molluscs

Molluscs are a broad group of animals, ranging from octopus, squid and cuttlefish to mussels, oysters, clams, scallops, sea snails and nudibranches. There is an amazing variety of species, with interesting characteristics. Many molluscs, like oysters, mussels, clams, scallops and sea snails have an outer shell that they live in. Sea slugs and nudibranches do not have a shell, and cephalopods (which include octopuses, squid and cuttlefish) are also free-moving with no outer shell.

Octopuses have no skeleton, allowing them to squeeze into and through small spaces. They have eight legs, and are believed to be extremely intelligent. When surprised or disturbed the octopus can produce a jet of ink to distract a predator and allow it to escape.  Squid and cuttlefish have eight arms and two tentacles. Squid do not have skeletons, however they have an internal shell-like structure which supports their body. They are also able to change colour according to their environment, and are extremely fast swimmers. Cuttlefish have an internal shell called a cuttle, this is unique in shape and size to each species and helps keep the animal buoyant in the water. Octopus, squid and cuttlefish are all able to change colour according to their environment, as their skins contain 'chromatophores' which allow the pigments to change and reflect differently. You can read more about cephalopods here

Bivalve molluscs include clams, oysters, flame shells, scallops and mussels. Each species is characterised by living inside a hinged shell, and most species in this group are filter feeders. Northern Ireland has both mussel and scallop fisheries. We also have a long lived species of mussel called a horse mussel (Modiolus modiolus) which can live to more than 70yrs of age and forms dense reefs for other species to settle on. An important site for this species was in Strangford Lough, although many of the mussel beds were damaged or destroyed.

Nudibranches are closely related to marine sea snails and slugs. There are over 3000 different species of nudibranch. They are often very colourful. Species in this group occur all over the world, including in Northern Ireland. They have tentacles on the top of their head which are sensitive to touch, taste and smell. To read more about the different species of nudibranches in the UK and Ireland you can go here.

Cnidaria- Anemones, corals, hydrozoans and jellyfish.

In the Cnidaria group, anemones, sea fans and corals live their life attached to the sea bottom or rocks, and do not move around to feed.

Anemones and Corals

The body of a sea anemone includes a 'polyp' with a disc and adhesive foot to attach to the bottom, and an oral disc opening in the middle of the polyp for eating its prey, with tentacles on top. They use their tentacles to capture prey and for defending themselves against predators. In Northern Ireland's seas there are soft corals, rather than the 'hard' corals which build reefs in tropical oceans. Unlike anemones which are single polyps, the soft corals are formed by a colony of polyps. A common soft coral in Northern Ireland is called 'Dead Man's Fingers'

Jellyfish and Hydrozoans

Unlike anemones and corals, which spend their lifetimes fixed to the one spot, the jellyfish is free-moving and mobile. Despite its name, jellyfish are not fish. There are many different species of jellyfish, however they all have the same basic shape. The body has an umbrella like shape (the medusa), with stinging tentacles trailing beneath it. There is a wide range of sizes across the different species of jellyfish, from 1 millimetre diameter to 2 metres in diameter.  Jellyfish do not have a nervous system, but instead have a net of nerves distributed across its body. They are carnivorous, feeding on other jellyfish, plankton and small fish. They, in turn, are eaten by sharks, turtles, and certain species of fish. They occur in all the world's oceans. Under certain environmental conditions, jellyfish can reproduce and grow rapidly, forming vast 'blooms' of jellyfish. Some scientists believe that blooms of jellyfish could indicate a deterioration in ocean health (eg. climate change, over fishing), however there remains a lack of scientific data to prove this.

Hydrozoans are a group of very small, carnivorous animals that can occur either on their own or in a colony. They can have either a free-moving or fixed 'medusae' stage or a polyp stage called 'hydroid', or a combination of both. When in hydroid form, these animals are generally living in a colony, with many species forming tree-like or fan-like structures. Colonial hydroids include polyps which are specialised for certain tasks, such as reproduction and digestion and in some species there are polyps specialised in defense.  

Porifera- sea sponges

Northern Ireland is globally important for its biodiversity of sponges, with around 200 different species, some of which have only ever been recorded in our waters. Sponges are sedentary animals, remaining mostly fixed in the one place on rocks or sea bed. They do not have a nervous system, or circulatory or digestive systems. Instead they are made up of pores and channels which allows water to circulate inside them. Their cells have tiny parts called 'flagella' which pump the water through these pores in one direction, allowing them to filter their food directly. It is believed that they are one of the earliest animals, and ancestor to all higher (more complex) animals. There are four groups of sponges; the glass sponges, the calcerous sponges, the demosponges, and the cladorhizidae. The waters around Rathlin island are excellent places to see many different species of sponges, as 134 species have been recorded there, including 29 entirely new species. You can read more about the different species in Sponges of Britain and Ireland from the Ulster Museum and in the NIEA report on Rathlin Island.

Seaweeds are plant-like macro-algae. Like land-plants they are vitally important to the ecosystem, as they provide food and habitat to countless marine and coastal species. They produce food through photosynthesis. Northern Ireland has many different types of seaweed, some of which are harvested and have a long history of being eaten by people. There are three main groups of seaweed: brown algae, red algae and green algae.

Brown algae

Most species have a green/brown colour. The different species range in size from only a few centimeters to 45m long. This group includes the iconic 'kelp' seaweeds, which are often large in size and can grow in dense 'forests'. One important species is the knotted wrack, which can be found around our shores, in our sea loughs and in shallow coastal waters. It is distinguishable by its many round air bladders within each frond. It is listed as a Northern Ireland Priority Species, as any threats to it would affect many other species around our shores. A good place to see this species are the shores of Strangford Lough. To see some good examples of kelp seaweed forests, such as the species known as tangle/cuvie, go for a snorkel around Dunseverick harbour on the North Coast. If you would like to find out more about seaweed harvesting, read the Department of Environment's summary document.

Red algae

There are estimated to be be over 3,000 marine species of red algae, and it is one of the oldest algal groups in terms of its evolution. Species in this group of algae are important in building coral reefs in tropical seas, and in the colder European seas certain red algae species with hard, chalky outer layers form maerl beds. Maerl is the collective term for this group of rock-hard red seaweeds, and the beds form important reef-like habitat for many species, including as a nursery ground for important commerical fish species. You can read more about maerl from the Natural England website.

Dulse is another red algae which is found around Northern Ireland's coast. It grows in both the North-East and North-West Atlantic, and reaches a maximum of 30-40cm. This species has both male and female individuals, however females exist as micro-scopic crusts and so are nearly impossible to find in the wild. This means that dulse found on the shore will be all male. It is also a species which has been traditionally eaten in Ireland, Iceland and North America.

Green algae

The green algae are a large group, with both freshwater and marine species. They are the ancestors of land plants. Almost all contain specialised green pigment (chlorphyll) for photosynthesis. One easily recognisable marine species is the sea lettuce, which is common around the island of Ireland. It is edible and a good source of vitamins.

Want more information?

The Irish Seaweed Research Group at the University of Galway has produced factsheets on common species along the Irish coast: Macroalgae Fact-sheets.

Sea-grass/eel grass

Unlike the algae species described above, sea grass species are classified as true plants- the only plants which are truly marine. In Northern Ireland there are three species off eelgrass, the common eelgrass , dwarf eel grass, and narrow-leaved eelgrass found in sea loughs and other sheltered bays and inlets.  Much less common, there are two species of tassel weed, which have occasional records from our shores. You can read the Northern Ireland draft Action Plan for sea grass species here.

Globally our seas are in trouble, facing:

• overfishing & collapse of fish stocks
• habitat damage and decline caused by human activities (eg. damaging fishing practices, development)
• over-crowding of the sea from unplanned development
• pollution from chemicals and litter
• climate change (sea level and temperature rise, ocean acidification)

We need to act now to protect habitats, species and our own livelihoods.

While Northern Ireland can't solve these global problems on its own, it is important that we play our part in protecting the species and habitats that live in our waters.

Marine Protected Areas are a vital part of conservation efforts. The

There are different types of MPA, and different levels of protection which in turn change the levels of disturbance to the protected area. The Task Force is urging the Government to include in their network of protected areas a type of MPA called a Highly Protected MPA. These have been found to be extremely effective in many cases in both tropical and temperate (colder waters such as in Northern Ireland) waters. To find out how these protected areas work use the slider on the picture below to see how species can increase in number and size over time.