The whale shark is the largest fish in the world, as it is usually about 12 meters long, approximately, and weighs more than 20 tons. Unlike most sharks, it is not a great predator, but rather a peaceful-tempered giant with tiny teeth of just a couple of millimeters that feeds on filtering huge amounts of plankton, algae, crustaceans, and small fish.
Despite efforts to preserve the species, whale shark populations have declined dramatically in recent years globally.
So, are whale sharks in danger of extinction? In this GreenEcology article we will talk about its conservation status, how many whale sharks there are in the world and, if so, we will explain why the whale shark is in danger of extinction.
Is the whale shark in danger of extinction or not?
The whale shark ( Rhincodon typus ) is the largest of all chondrichthyans, the class of cartilaginous fish to which sharks belong. They are ovoviviparous and migratory creatures that feed by filtration and can live for more than 100 years.
One of the greatest curiosities of the whale shark is that, like human beings we have fingerprints, they have unique and unrepeatable dorsal body patterns that allow them to differentiate from each other.
Whale sharks have very few natural predators, the main ones being killer whales, other large sharks such as the great white or tiger shark and, lastly, humans. If you want to know more about the Types of sharks: how many there are and species , read this article that we recommend.
They are an endangered species . Its population has decreased by 50% in the last 75 years and it is estimated that it is between 7,000 and 12,000 specimens . Below we will look at some of the causes why the whale shark is threatened and we will mention other measures that can be implemented to help conserve the species.
The main threat to the whale shark is overfishing or overfishing, as for other species. Although whale sharks do not pose any risk to humans and are a protected species in many of the countries and regions where they live, they are indiscriminately killed to sell their bodies for US $ 3,000 to US $ 4,000.
In many parts of the world its meat is consumed, which is considered a culinary delicacy. Its fat is also used to make cosmetics, medicines and vitamin supplements , and in some places it is even believed that certain parts of the whale shark have aphrodisiac, healing and magical properties.
They are not aggressive animals, they move at a speed that does not usually exceed 5 kilometers per hour and they do not fear or avoid people, so it has been very easy for the large Chinese, Taiwanese and Philippine fisheries to capture them.
Trawling is the most environmentally damaging type of fishing that exists. It affects multiple species (some of them are not even commercial) and destroys the seabed, the ecosystem and the ecological balance of the places where it grows.
Whale sharks are sometimes accidentally caught and killed by getting caught in fishing nets used in trawling. Many of the times the whale shark survives capture, it is returned to the sea with injuries, lacerations and even mutilations.
Collisions with ships
More than 20,000 whales are believed to be killed each year by fishing boats, cargo ships and cruise ships. In most cases the crew is unaware of the collision and the animal dies and sinks without a trace. Here you can find out more about Why the blue whale is in danger of extinction and Beluga whales in danger of extinction .
Collisions between boats and whale sharks are also very common. They can cause injuries, lacerations, mutilations, and even death to affected specimens.
Pollution and destruction of their habitat
Whale sharks are migratory fish that inhabit the Pacific, Atlantic, and Indian Oceans. They prefer the warm waters of the tropics, but can be found in colder waters, such as those off the coast of New York or South Africa.
Although whale sharks are usually inland (at depths between 200 and more than 1,500 meters), it is quite common to see them off the coast, swimming in coral reefs or bays. Whale sharks have been sighted off the coasts of more than 90 different countries , with the largest populations in the Philippines, Taiwan, the Galapagos Islands, Mexico, Australia, South Africa, the Maldives, Mozambique, India and China.
The human being is the main responsible for the pollution of the oceans . Here are some human activities that damage the habitat of whale sharks:
- Mismanagement of waste : all the garbage, plastics, sewage and chemical waste that are thrown into rivers and seas pollute the water and affect aquatic ecosystems.
- Irresponsible Tourism : In some places, whale sharks are tourist attractions. When tourism is done in an invasive way, it can put stress on the animals and interfere with their feeding, reproduction, migration and lifestyle in general. If you want to know more about responsible tourism: what it is and examples , do not hesitate to read this article that we recommend.
- Trawling : trawling is one of the main causes of the degradation of marine soils, affecting countless populations, food chains and ecosystems.
- Oil spills: when oil leaks from the vessels that transport it, it contaminates innumerable amounts of water.
Climate change is causing the temperature and acidity of ocean water to increase. The change affects the feeding and development process of many marine species, including whale sharks.
The plankton , nekton, some algae and many small fish, arthropods and mollusks which feed the whale sharks are affected by climate change. If their populations decline, the food for whale sharks may become scarce.
If we want to save the whale shark we have to take measures that allow its population to increase quickly and efficiently. The human being is the cause of the vast majority of the factors that threaten the whale shark, so all efforts to recover the species must be aimed at reducing the environmental impact that people generate.
Some steps we can take to prevent whale sharks from becoming extinct in the near future include:
- Raise awareness in other people through the dissemination of truthful information about the conservation status of whale sharks.
- Promote and practice sustainable ecotourism .
- Avoid buying disposable plastic containers and other single-use products that are not biodegradable.
- Recycle and reuse to generate as little waste as possible.
- Do not throw garbage into rivers or the sea.
- Do not buy meat or products made from whale shark parts.
- Do not dispose of substances that can contaminate bodies of water, such as vegetable oils, petrochemicals or fertilizers.
- Contribute to research programs that favor the preservation of the species, either through donations, volunteering or dissemination. There are projects dedicated to safeguarding whale sharks such as Sharkbook: The Wildbook for Sharks and The Maldives Whale Shark Research Program .