Endangered Sea Animals

Hundreds of thousands of once common animals are endangered.  In the seas these range from tiny plankton to the great whales and sharks.  Many creatures we probably do not yet even know exist.  Our knowledge of the oceans is still limited and hundreds of new species are being discovered every year.  Some animals may well be gone before we find them. 

This article is focusing on just three sea animals;. the Atlantic bluefin tuna, the hawksbill turtle, and the dugong.  These animals are critically endangered because of the threats affecting all ocea ecosystems.  These include climate change, pollution and overfishing.  All three have also been hunted way more than their populations could ever sustain.

Bluefin tuna

Atlantic bluefin tuna (Thunnus thynnus), are critically endangered and populations have plummeted by over 70%.  The main cause is, perhaps unsurprisingly, overfishing.  Although they are a popular target of sports fishermen because of their size, adults average 2 metres or more,  the real threat comes from commercial fishing. 

Thousands of tons of tuna are caught each year, legally and illegally.  This is way more than can be supported.  Unsustainable fishing is not just a problem for the tuna themselves, it is a problem for those that eat them (including us) and the animals they themselves eat.  Tuna occupy a key position in the food web and are crucial to the ecological balance in the Atlantic.

Hawksbill turtles

Of the seven species of marine turtle still surviving, the Hawksbill turtles (Eretmochelys imbricata) are one of the smallest and the most endangered.   They are threatened by the same things that threaten all marine turtles which include entanglement, pollution, climate and overfishing of their food. 

However their main problem is being hunted.  They are targeted for their shells, which are made into tortoiseshell jewellery and other ornaments and souvenirs.  The fact that equally beautiful things could be made from artificial alternatives is of course never taken into consideration.  Mainly because of this trade their numbers have dropped by at least 80 per cent.


Everybody is well aware of the threats posed to whales and dolphins, and fairly effective conservation efforts have been put in place with many populations recovering.   There are, however, other marine mammal species in great danger and the dugong (Dugong dugon) is one of them.  These peaceful marine herbivores are also called sea cows, and they do look a little like a cross between a dolphin and a cow.  

Dugongs are supposed to be the animals that gave rise to legends of mermaids.  Although they don’t look very much like mermaids there is sadly a good chance they could end up as rare, i.e. not exist.  Because they are long lived but reproduce slowly they are very vulnerable.  Populations simply cannot recover quickly, if at all. 

Many dugong populations are near extinction, and the species overall has a good chance of disappearing altogether.  As with the hawksbill turtle one of the main threats is hunting. In the case of dugongs for meat and blubber.  They also suffer from collisions with boats and all the other threats outlined earlier.

The oceans are often ignored simply because we cannot see what is happening down there.  It is time to realise that some of the most interesting, beautiful and vital animals on our planet are in them, but might not be for much longer if efforts are not made to protect them.