Elasmobranchs are one of the most successful and resilient group of species ever to inhabit the earth. They have swum the world’s ocean for the last 400 million years and have even survived the mass extinctions which wiped out the dinosaurs. However, today they face the biggest threat to their survival and something which may drive many species to extinction, mankind.
Over 100 million sharks and rays are killed each year either intentionally or by catch in commercial fisheries. Coupled with the slow growth rate and late maturity of most species, this is having a devastating effect on populations of many species.
Many populations around the world have declined by 90% in the past 50-100 years and in the Northeast Atlantic 26% of species are classified as threatened. The situation in the Mediterranean is even worse with 42% of species considered threatened and some large predatory sharks such as hammerheads, blue sharks, makos, threshers and porbeagles have declined between 96 and 99.9%. These are some of the most heavily fished waters in the world and if current trends and fishing practices persist it is likely that we will witness the extinction of many species within our lifetimes.
Why are people slaughtering elasmobranchs?
1. For their meat
Some shark meat is highly prized particularly in the continental market whilst other species are considered unpalatable due the ammonia in their tissue. Species such as porbeagles are caught in seasonal directed fisheries, which target large aggregations of these sharks. This can have big effects on the population structure as large sharks may be preferentially targeted and these are likely to be mature females who contribute significantly to the reproductive success of the population. Elasmobranchs are also taken as bycatch in both bottom trawl and long-line fisheries. Some are retained if they can be sold however many are dumped back dead into the sea.
The main countries involved in shark fisheries in Europe are Spain, France and Portugal. There are very few if any regulations regarding shark fishing in European waters, unlike other valuable fish such as cod and tuna, which have quotas and management measures. Therefore fishermen are basically allowed catch as many sharks as they want or can fit on their boats.
2. For their livers
Sharks, unlike most bony fish, do not have a swim bladder and rely on a large oil filled liver to regulate their buoyancy. In the 1930s and 1940s shark liver oil was used as a high quality lubricant which prompted a boom in fisheries for sharks with large livers such as basking sharks (Irish fisheries off Achill Island and in Donegal Bay) and deep water species. In fact the street lights in Dublin used to be lit with basking shark oil.
Once synthetic oils were developed the shark liver oils market collapsed however they are still used in the cosmetics and pharmaceuticals. Squalene is extracted from the livers and is included as a moisturising base in creams and lotions. Fortunately this practice is becoming rarer although many of the top brands still use this in their face creams and lipsticks. If you don’t want to be rubbing shark liver into your face it is worth checking the ingredients list and avoiding products that contain it.
3. For their fins
Shark finning is the practice of cutting off a shark’s fins and dumping the live shark back into the sea to die a slow and painful death. The fins which are composed of cartilage are then dried and sent to the Asian market for use in the making of shark fin soup. The soup, which is a symbol of wealth in Chinese culture, can sell for upwards of $100 a bowl. The fin cartilage does not add any flavour to the soup but is used merely for its gelatine like texture.
The main country involved in shark finning and fishing in Europe is Spain although France and Portugal also have large landings. Sharks are generally caught on drifting long-lines, which as the name suggests is a long line of baited hooks which drifts. The surprising thing is the length of these lines. They can range from 20 to over 100 km long and have more than 1000 baited hooks on then. To put this in to context imagine a single line stretched completely across the Irish Sea between Dublin and Holyhead in Wales with a hook every few metres. Any animal, be it shark, tuna, sea turtle or even dolphin within the area is likely to get hooked. There are approximately 189 registered boats that do this in European waters and each boat is capable of catching and storing around 25-50 tonnes of sharks on each trip they do. The scale of the slaughter is almost unimaginable.
Until recently, usually only the fins were retained and the bodies dumped at sea however regulations have been introduced regarding the ratio of fins to bodies that a boat can legally land. This is a very complicated system and leaves plenty of scope for illegal fishing. If shark fishing is to persist then sharks regulations should be introduced where sharks must be landed with the fins still attached to the body.
4. For sport
Back in the 1950s and 1960s shark fishing was becoming very popular in Ireland but at this time almost all those caught were taken ashore for weighing and photographing and fishing quays covered with dead blue sharks were a regular sight during the summer months. These sharks would then be dumped off the quay or taken back out to sea for dumping. This was common practice at the time and happened in many other countries also. Declines in catches were soon noted and in Ireland the Marine Sport fish Tagging Programme was established by the Central Fisheries Board (then known as the Inland Fisheries Trust).
This step towards catch and release angling was extremely important for shark conservation and thankfully it has become the accepted norm for shark anglers in Ireland, most of whom would not even consider killing a shark for the sake of a photograph or a record. Unfortunately though some people are still in the mindset that the only good shark is a dead shark and annual shark derbies and shark hunts are common practice in many areas including North America and Australia in particular. It is often the largest individuals that are killed and taken ashore for weighing and these are likely mature or even pregnant females. It is clear that sharks are under enough pressure from commercial fisheries and could do without the added threat of trophy hunters.
Targeting sharks for recreational angling can be an exciting experience and if the shark is treated well and tagged and released it can provide valuable scientific data which may be used to help conserve the species.
What can you do to help save elasmobranchs?
- Don’t eat shark or rays or any products made from them.
- Don’t use cosmetics with shark liver squalene in them.
- Don’t kill sharks for angling. Carefully release them at the side of the boat if possible and avoid the sensitive stomach area. Support the body at all times when out of the water and do not suspend them by their tail.
- Join the Irish Elasmobranch Group and get involved in conservation projects.
- Check out the Shark Alliance website for more information about shark fisheries and finning.