Cetacean hotspots in the Philippines identified

Jo. Florendo B. Lontoc, Manila Bulletin 3 Jun 09;

Prof. Lemnuel V. Aragones of the UP Diliman Institute of Environmental Science and Meteorology, an expert on marine mammals, recently revealed that there are a host of potential cetacean eco-tourism “hotspots” in the country.

However, he also warned about the many dangers that these marine mammals could face as a result of tourism activities.

His findings, the result of more than 10 years of studying Philippine waters, clearly demonstrate how Philippine waters are richer in dolphins and whales than anybody assumes.

The cetaceans together with the dugongs, a marine herbivore, are the marine mammals found in the Philippines.

Aragones said the term “cetacean hotspots” also underscores the fact that they are areas of concern.

“These are places where you have a great diversity and abundance of marine mammals and presence of apparent conflicts [related to human activities such as fishing] which could have deleterious effects on these animals.”

Among these dangers are the proliferation of trash, abandoned fishing nets, and the increasing number of active fishing gear such as nets and permanent fish corrals and cages. Cetaceans mistake trash for food and get entangled or trapped in the nets.

Overfishing, meanwhile, could deprive dolphins and whales of their food. Dugongs are especially vulnerable to human activity because they survive only along coasts where seagrass, their staple, can be found and where human activities are also greatly felt.

All cetaceans in the Philippines are in danger of being hunted. Some are run over by boats. Underwater noise from dynamite blasts and seismic surveys can damage their hearing and impair their ability to navigate.

“Being watched by tourists should not add stress to their existence,” Aragones said. “Dolphin-watching and other such economic activity should be conducted with high standards of professionalism or else it won’t be sustainable.”

Aragones and his co-researchers have documented 28 cetacean species in Philippine waters, or more than a third of all cetacean species in the world.

Hotspots for dolphin and whale watchers include the areas off the Batanes and Babuyan groups of islands, Cagayan, Isabela, Aurora, Bataan, and Zambales in Luzon.

Other hotspots include the Sulu Sea off southern Negros and the Zamboanga peninsula; Tañon Strait between Negros and Cebu islands; the sea between Bohol and Misamis Occidental, Lanao del Norte, and Misamis Oriental; or the waters off the Bohol Triangle consisting of the islands of Bohol, Siquijor, and Camiguin.

The dugongs, now classified by the International Union for Conservation of Nature (IUCN) Redlist as vulnerable to extinction, are distributed along the northeast and the entire eastern coast of Luzon; all coasts of Palawan; the coasts of Guimaras, southeastern Panay, and northern Negros; the entire southern coasts of Mindanao island; the coast of Agusan del Norte; and the coasts of the Basilan, Sulu, and the Tawi-tawi group of islands.