The Whale Shark

The Rhincodon Tyous, more commonly known as the whale shark, is a highly migratory, pelagic species, recognized for being the worldʻs largest shark. They are plankton-eating fish that are not dangerous or aggressive towards humans. However, the same cannot be said about humans toward these gentle giants. Whale sharks generally roam the ocean alone, but now they are in need of help, as are many other sharks. They are globally listed as “vulnerable to endangered” by IUCN red lists, and now is the time to make efforts to change this classification before it is too late.

It is no surprise that the major threats to sharks are induced by human activity. Finning, plastic ingestion, bycatch, speed boats, fisheries, and even tourist operations are just a few of the key threats responsible for the decimation of this species. Whale shark meat has grown in demand over the last 30 years due to various reasons. In the late 1990s, a whole shark could be worth up to tens of thousands of US dollars (depending on size and weight of the animal). The sharks’ soft meat is consumed by the general public around the world (predominately in Asia), and oil from the sharks’ livers has been used for anything from shoeshine to treatment for waterproofing boats. Recent surveys have shown an increased demand for the fins as well. The fins are highly valued on international markets, especially for their size, which is why they are often sold as display or trophy fins. This continued demand for the fins, meat, and oil is a high threat to the existence of this species.

Unregulated fisheries are also causing a decline of these creatures. Even if the sharks are not purposefully targeted, they are regularly captured and retained if spotted. Bycatch is an issue as well. Bycatch is the term used to label any fish or other marine creatures that are unintentionally caught during commercial fishing for a certain species. Unfortunately, whale sharks are subject to this type of death, like many other shark species, and they have been largely found as bycatch off of mainland China.

Tourism can also pose a threat to whale sharks, due to the fact that it can interrupt their feeding patterns and possibly their migration routes. This is connected to damage to the animal by boat as well. Boat propellers have the potential to injure the sharks, and the risk of this is increased by the fact that whale sharks tend to swim near the surface. It is also believed that negative effects toward migration routes of these animals could occur because of increased levels of noise and pollution from boat traffic. Additionally, sharks sense sounds as pressure through their individual lateral line systems. It is possible that very loud sounds may even negatively affect their everyday behavior (such as feeding, mating, migration, etc.). The sharks’ movement may also be affected by longer-term and cyclical shifts in climate. Unfortunately, all this is made significantly worse by the fact that whale sharks are known to take up to 30 years to reach sexual maturity, making the killing of these animals extremely unsustainable.

While it is evident that humans have negatively impacted the global population of whale sharks, efforts are also being made to save this species. Scientific research has been/is being conducted in the form of satellite tags, sonar devices, and digital cameras. Photographic ID is a non-invasive way to track whale sharks. Unlike other

sharks, juvenile whale sharks exhibit their same skin patterns throughout adulthood. Scientists and conservationists are using spot recognition software to identify whale sharks by their unique spotted markings along their forward flanks. This process relies on the spot pattern found from the segment posterior to the 5th gill slit of each shark. One can also tell the difference between male and female whale sharks by the existence of claspers on the males.

Various international studies are being held on other issues that could affect this species as well. For example, current studies are being performed to determine the impact of marine micro-plastics in Western Australia, Indonesia, and the Philippines. Plastic pollution poses a major threat to all marine species, however, micro-plastics have a greater chance of being ingested by animals, especially those who spend time near the surface. Ingested plastics can block an animalʻs digestive tract, reducing its ability to absorb nutrients, etc.

Other conservation efforts are done by programs such as World Wildlife Foundation. These conservation efforts include legal protection and regulations. Whale sharks are legally protected in Australian Commonwealth waters, Queensland, Tasmania and Western Australia, the Maldives, the Philippines, India, Thailand, Malaysia, Honduras, Mexico, in U.S. Atlantic waters, and in a small sanctuary area off Belize, along with other location in consideration of these legal efforts. In Western Australian waters, whale sharks are protected under the Wildlife Conservation Act of 1950. Other regulations have been made to protect these sharks from live whale shark trades and the sale of their shark meat, etc. Enforcing existing laws for fisheries and fishermen is very important as well. Ecotourism projects are also working on promoting safe interactions among whale sharks and humans, while promoting the regional tourist economies. These require high monitoring to make sure that the increase of tourism does not negatively affect the sharks’ behavior.

Fortunately, there are ways that everyone can help, even if not involved with an organization. Some great ideas would be to hold/join protests and sign petitions. For example, support protests against fisheries targeting these sharks or producing a lot of whale shark bycatch. Another way one can help is by supporting habitat sustainability by attending beach cleanups and events that positively impact the environment.

There are also three very beneficial ways everyone can get involved in saving sharks right from their own living room: BE AWARE, RESPECT, SHARE! By being AWARE of the importance of sharks and the plight of their species, you hopefully can gain or expand your RESPECT for their vital work and role. Then you can SHARE the respect and knowledge you have on them with those around you!

Thank you for supporting shark conservation, and doing your part to help make sure that human activities stop having adverse effects on sharks!

*Websites I used:

http://www.iucnredlist.org/details/19488/0

http://www.abc.net.au/news/2015-12-04/manta-ray-breeding-threatened-by-plastic/ 6998334

http://animaldiversity.org/accounts/Rhincodon_typus/[page3image2008] [page3image2168] [page3image2328] [page3image2488]