More Than 70 Giant Freshwater Stingrays Mysteriously Died In Thailand River

More than 70 giant stingrays were spotted dead in Thailand's Mae Klong River in the past few weeks. The cause of their death seems mysterious and the officials are now investigating what killed these car-sized stingrays.

https://t.co/s08qnsEUv9 70 Car-Size Stingrays Die Mysteriously - The huge freshwater fish may have been killed by pollution in Thailand's …

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National Geographic reports that the Mae Klong River is slightly more acidic than the usual rivers. On the other hand, it is unclear yet if this is relevant with the deaths of the freshwater stingrays. As of now, Zeb Hogan from the National Geographic and other scientists are studying the fish in Thailand. The International Union for the Conservation of Nature listed the giant freshwater stingrays as endangered.

There are some speculations from Thailand environmentalists that the recent spill from an ethanol plant could have toxified the freshwater stingrays. Some theorize that they might have been poisoned by cyanide that intends to kill other desirable fish. Stingrays are often not caught by fishermen because they are not good to eat and they tend to break the fishing gear.

The stingrays are also threatened by oil spills, pollution and dams that have broken their environment. Hogan said that a reduction of pollution from surrounding factories is needed to improve the health of the river and save the stingrays in the long term. He hopes that the international coverage will encourage more measures to protect the stingrays.

Stingrays are cartilaginous fish that are related to sharks. They comprise of eight families, namely, the deep-water stingray, sixgill stingrays, whiptail stingray, round rays, butterfly rays, river stingrays, stingarees and eagle rays. They used their barbed stingers on the tail for self-defense. Their stingers could reach around 35 cm (14 in) in length and have two grooves called venom glands on their underside. Stingrays can be found in subtropical marine waters and coastal tropical waters around the globe.