With all the talk in recent months of protecting elephants and rhinos, there is a third major species problem – this one in our oceans. Sharks are under threat and have been for many years. Despite international efforts to curb illegal hunting and fishing, many sub-species face the threat of extinction.
What Is a Shark?
Sharks are classified as a type of fish with between five and seven pairs of gills, a body made of cartilage and a pectoral fin that is not fused to the head. The smallest is the pygmy shark at just 22cm (9 inches); the two largest are the gentle giants of the seas – the basking shark (6-8m / 23-26ft) commonly seen around Britain’s coasts, and the whale shark (12m / 41ft) seen in more tropical seas.
They are predators and some of the most common such as the great white, tiger, blue and hammerhead are referred to as “apex predators”. So-called apex predators sit at the top of the food chain and are not prey for any other species. They perform a vital role of population control in the oceans, much like wolves, lions and tigers do on land.
Thanks largely to the book and film ‘Jaws’ in which a great white shark munches its way through a buffet of Long Island residents. Sadly, sharks have a reputation as dangerous to people. This reputation is not entirely unjustified, but shark attacks on people are rare. In 2015, just six people died in shark attacks globally. Injuries were more numerous; there are around 50 shark attacks in the USA every year. It is a threat, but you have a greater chance of winning the lottery.
Humans kill around one hundred million sharks every year.
Threats from Illegal Hunting
The largest threat to the world’s shark populations is hunting:
- The mistaken belief that they are a threat to humans, our livelihood and economy and as ‘revenge’ attacks.
- It is believed that some parts of a shark’s body have magical healing properties. None of these claims have ever been proven.
- Sharks are hunted for food. Shark fin soup is a delicacy in Asia and in great demand, but stocks are unsustainable. Some shark is sustainably fished though (see below).
Most species, particularly the great white, are protected by international laws but efforts to curb hunting is not always easy.
As well as the deliberate hunting, fishing practices in some parts of the world have led to accidental capture and death. People are not deliberately hunting these creatures; instead, they are getting caught up in nets in lucrative fishing grounds as they themselves are looking to feed. Reform of fishing methods is the best way to handle these accidental deaths – new types of fishing methods include ways of avoiding or releasing sharks back into the wild.
Some sharks are sustainably fished and not all are under threat. In India, baby sharks flake into a delicacy when cooked. In Australia, a fillet of shark is the most common form of fish used in fish & chips (gummy sharks are sustainable as they reproduce quickly).
In Europe, we eat a lot of dogfish – this is a type of shark too. In fact, Europe is one of the major markets for sustainable (and legal) shark fishing. However, Greenpeace and other groups advise consumers in the US and Britain not to eat shark.
As with many other things, the changing climate, pollution and underwater developments are pushing vital shark species away from their conventional hunting grounds. As ocean acidification rises with rising sea levels and the oceans absorbing more carbon, it is not known what effect this is likely to have on the world’s sharks, although as we have observed with other fish species and coral, it’s likely to be largely negative. More sharks will compete for fewer resources as prey species tumble in number. Sharks have a highly developed olfactory system (scent), and the changing ocean chemistry has already been shown to affect their hunting capabilities.
The Shark Trust is currently the only UK registered charity working to advance the worldwide conservation of sharks. Visit their website at http://www.sharktrust.org/en/shark_conservation.