Posted on March, 09 2009

The shock discovery in the Philippines of a tiny whale shark – possibly the smallest of its kind ever recorded – has given scientists new insight into the breeding behavior of these mysterious fish.

Scientists from WWF-Philippines, working with local police and government officials, freed a 38 cm whale shark over the weekend captured by a fisherman in the Philippines province of Sorsogon, near the coastal town of Donsol, a hub where whale sharks congregate.

The rescued shark was the smallest whale shark ever recorded in the Philippines, and possibly the smallest ever found in the world.

The whale shark is the world’s largest living fish, measuring up to more than 12 meters and weighing up to almost 14 tons, making the weekend encounter by scientists with the miniscule captive whale shark a unique opportunity to learn more about the huge fish species.

Despite all the ongoing research on whale sharks, little is known about where they breed or give birth.

Because of its small size, the whale shark found in the Sorsogon Province was likely born near the area. This indicates that the Philippines – at the apex of the Coral Triangle – likely is one of the places where these giants of the sea are born, according to WWF-Philippines.

For many years, scientists thought that the Sorsogon coastline was merely one of many stops along the global network of marine highways traveled by whale sharks. The recent discovery of the small whale shark could change that long-held belief and instead establish the coastline as a birthing area for the sharks.

After being tipped off that a whale shark had been caught to be sold, researchers from WWF-Philippines alerted local authorities and together they located and freed the shark, which the fisherman had restrained with a rope tied around its tail.

The rescuers then checked to make sure the shark had not been injured, and documented and measured it, before transferring it into a large, water-filled plastic bag to allow it to swim freely prior to its release. They eventually took the shark out to deeper water, where it was less likely to get entangled in a fish net, and set it free.

Although listed under Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), a status which strictly regulates the trade of the species based on quotas and permits to prevent their unsustainable use, whale sharks continue to be harvested for a variety of products, including their liver oil and fins.

The waters around Donsol are part of the Sulu-Sulawesi Seas ecoregion, one of WWF's Global 200 ecoregions — a science-based global ranking of the world's most biologically outstanding habitats and the regions on which WWF concentrates its efforts. The also make up part of the Coral Triangle, a major area of marine biodiversity.

Leaders of the six nations that make up the Coral Triangle – Philippines, Indonesia, Malaysia, Papua New Guinea, Solomon Islands and Timor Leste –will meet on May 15 in Manado, Indonesia for the World Oceans Conference where they will announce a comprehensive set of actions to protect ecosystems and food security in the region.



(C) WWF-Philippines