Which Fish in British Waters are the Most Endangered?

When we think of endangered species, fluffy pandas and snow-white polar bears often spring to mind. But what about fish? You might not think of them as particularly cuddly or photogenic, but many species of fish are also under threat. A report by the World Wildlife Fund in 2017 found that one in four fish species across the globe are threatened with extinction. The same report revealed that 25% of British freshwater fish are at risk from human activities like pollution, dams, and land reclamation. If you love fish but want to ensure that this isn’t putting any important species at risk, it’s worth knowing which ones you should leave alone if you want to keep seeing them in our seas, rivers and lakes for years to come.

Here is a breakdown of some the most endangered fish in British waters.

Arctic Skate

This large, green fish with a spiky tail has been a victim of over-fishing for decades. The fish’s eggs have a very short lifespan, meaning that fishing them has a more serious effect on the species than harvesting the eggs of other species. The Arctic skate is found in the North Sea, the Irish Sea, and the English Channel, and it is under extremely strict protection in the Channel due to its declining numbers. The European Union has placed a ban on all commercial fishing of skates and rays, and there is also a ban on landing them in the English Channel. There is no commercial fishing of these species in the Irish Sea, and you can only catch one skate per person per day in the Irish Sea. However, in the North Sea there are no restrictions on harvesting skates and rays, and they are therefore at risk of being over-fished.

Eurasian Bullhead

This freshwater fish is relatively rare, and it has been found that populations in the River Thames are now at less than 10% of what they were in the 1970s. The fish is believed to be declining due to the fact that certain species of fish eat it as a source of food. Man-made obstructions, such as boat ramps and weirs, are also putting a strain on this species as they are preventing it from breeding in large numbers. The bullhead is native to the River Thames in England, the River Ouse in Yorkshire, and the River Wear in Durham, but it is also found in the southern part of Scotland. The fish is protected in England and Scotland, and the Environment Agency is currently developing a management plan for it. It is also listed as threatened by the IUCN Red List.

European Eel

The European eel is a freshwater fish that can be found in European rivers, as well as many parts of North America. It is listed as critically endangered due to overfishing and habitat loss. There were once hundreds of thousands of eels in British waters, but by the start of the 20th century, the population had declined by around 90%. The eel is a migratory species, so it travels from the Sargasso Sea in the middle of the Atlantic Ocean all the way up to the Baltic Sea. Unfortunately, it is particularly sensitive to changes in water temperatures and levels, so it is at risk from climate change. Eels also require clean water, so they are often very negatively affected by pollution. Finally, they have also been overfished because they’re highly prized by sushi lovers.

The European eel has a long history of being commercially fished across Europe. In fact, it has been so heavily harvested since the 16th century that its population has struggled to recover. Eels have long been an important source of protein for many people in Europe, Asia and America, but commercial fishing for them has been banned in the EU since 2002.

European Sea Sturgeon

This is the largest species of sturgeon found in British waters, and it is currently listed as endangered. It is a freshwater fish that can be found in the Baltic Sea, Black Sea, North Sea, and Atlantic Ocean. It is listed as critically endangered due to overfishing, pollution, and river damming. The European sea sturgeon is currently protected in the UK, but there are no regulations in place to protect it in other parts of Europe.

Sea sturgeons can live for more than 100 years, but they’re particularly sensitive to changes in the environment. They are at risk from climate change, as higher sea temperatures can reduce the amount of food available in the sea.

The sturgeon is threatened by commercial fishing, pollution, and the loss of its natural habitat due to the construction of weirs and dams. The fish’s eggs are also collected for caviar, and this has also had a negative impact on its numbers.

The European sea sturgeon is found in the Thames Estuary, the Severn Estuary, and the rivers of Wales and Scotland. The fish has been listed as endangered since 2002, and it is currently under review for possible reclassification as critically endangered.

Giant Kelpfish

This species of fish has been found in very small numbers in the Irish Sea and the English Channel. It has also been spotted in the Baltic Sea, where it is thought to be migrating from British waters. The giant kelpfish is a tropical species, which has led researchers to believe that it is being transported to British waters in ship hulls. This fish is found in very deep water, and it is currently under review for protection under the Wildlife and Countryside Act. The giant kelpfish is currently listed as endangered on the IUCN Red List.

Glossy Sea Viper

This is another tropical species that has found its way to British waters. The viper is a venomous fish that is thought to have been transported to Britain in ship hulls. The viper has been found in the Mediterranean Sea, the Black Sea, the Baltic Sea, and in a few British waters. Although the viper is currently only listed as endangered in the Mediterranean Sea, it is thought that it could be migrating to British waters. This would lead to it being listed as endangered in these waters as well, as it is a protected species.

Though sea snakes are usually harmless, this species has a highly toxic venom that can cause paralysis. It lives in warm, tropical waters where it feeds on small fish, juvenile octopuses, and crustaceans.


This species of fish is listed as critically endangered, and it has only been found in the Ionian Sea and in a few British waters. It is thought that the mandarinfish is migrating from the Mediterranean Sea to British waters, and there are currently efforts to monitor its migration. The mandarinfish is very rare, and it is believed that there are only a few individuals in British waters. The fish is currently under review for protection under the Wildlife and Countryside Act. There are also efforts to try to identify the species’ migration route and find the best way to protect it from being accidentally caught by fishermen.

Mediterranean Bluefin Tuna

This large species of tuna is listed as critically endangered in British waters. It is thought that overfishing of the species in the Mediterranean Sea has led to it migrating to British waters. There have also been efforts to find new ways of farming the species, and it has been found in a few British waters, including the English Channel.

Popular with sports fishermen owing to it's size and speed the Mediterranean bluefin tuna is currently protected in the UK, but there are no regulations in place to protect it outside British waters. Mediterranean bluefin tuna are at risk from climate change due to their sensitivity to water temperature changes and water levels. They are also negatively affected by water pollution.

Orang Utan Fish

This fish is a species of coral trout that is currently listed as endangered. It is believed that this species of fish was introduced from the Caribbean Sea to British waters. There are currently efforts to find a way of breeding the fish in captivity, which would help to increase the number of wild fish. The orang utan fish has been found in smaller numbers in the Caribbean Sea and the Gulf of Mexico. It is believed that the species could be migrating to British waters, and there are currently efforts to find a way to deterine its numbers.

Shark species in British waters

As many shark species migrate to the waters around Britain each year, they are likely to be found in our seas, too. However, all species of shark are currently listed as endangered, particularly the Atlantic angel shark, the bigeye thresher, the porbeagle shark, and the smalltooth sand tiger.

The number of sharks in British waters has declined, and this is believed to be due to over-fishing, the loss of habitat in the Mediterranean Sea, and over-fishing in other parts of the world. There are currently efforts to find ways of recovering the numbers of sharks in British waters and in the rest of the world.

Sharks can live for up to 30 years, but they only reach sexual maturity after around 12 years. Once they do, they only give birth to around four live offspring every two years. This means that sharks are extremely vulnerable to overfishing. If there are too many sharks caught before they’ve had a chance to reproduce, it can have a really significant impact on their numbers.generations to come.