Alcuin Papa, Philippine Daily Inquirer 11 Feb 09;
MANILA, Philippines -- Experts are looking at dynamite fishing as a possible reason for the beaching of some 250 dolphins in Pilar, Bataan, on Tuesday.
Environment Secretary Jose “Lito” Atienza said he asked Bataan Gov. Enrique “Tet” Garcia in a meeting at the Department of Environment and Natural Resources offices in Quezon City on Wednesday whether there was dynamite fishing in his province.
“I asked him [Garcia] and he confirmed it. He also said he was battling this illegal activity,” Atienza told reporters.
Dr. Lem Aragones of the University of the Philippines Institute of Environmental Science and Meteorology, told reporters the melon-headed whales of the dolphin family could have been led astray by the leader of their pod.
In turn, the leader’s acoustic system, which serves as its guidance system, might have been impaired.
“The causes of the acoustic trauma could have been sound waves caused by dynamite fishing or sounds emitted by passing ships or seaquakes,” he said. But he said they had ruled out a seaquake as the cause.
Dr. Theresa Mundita Lim, director of the DENR’s Protected Areas and Wildlife Bureau (PAWB), said they found no lesions or other physical manifestations that the ears of the four dolphins that died had been injured.
“There were no injuries to their ears, like visible lesions, but the possibility of an acoustic problem or trauma is still there,” Lim said.
But she also said more tests, like analysis of tissue samples and MRI tests will have to be done to see if there were other injuries to the animals not visible externally. Lim also said they are sending tissue samples to the University of Philippines in Los BaƱos, Laguna for analysis.
She said dolphins usually venture into shallow waters to feed.
Joel Palma of the World Wildlife Fund (WWF) said dynamite fishing is usually done in shallow waters.
According to Lim, Atienza reiterated his directive to remove stationary fishnets and other obstructions in the sea off Pilar after one of the dolphins was found tangled in nets.
Lim added they are looking at the whole environment in Pilar to determine what might have caused the dolphins to beach.
“If it was something like climate change, then it would be a bigger environmental problem,” she said.
Malcolm Sarmiento, director of the Bureau of Fisheries and Aquatic Resources (BFAR) said the dolphins would not leave their leader or any member of their pod behind due to their strong social instincts.
But for now, Sarmiento said they had yet to determine who was the leader of the pod that beached in Pilar.
“Usually, it would be male, the biggest among the animals, and the most battle-scarred. He would be swimming in the middle part of the pod,” he told the Philippine Daily Inquirer (parent company of INQUIRER.net).
Aragones said the cause of beaching of marine mammals is not usually discovered. Around the country, there are 12 to 15 incidents of beached marine mammals every year, he said.
Lim also said that a protocol and guidelines for incidents of beaching by marine mammals would be drafted soon.
“In general, what we saw was good cooperation between various stakeholders in a stranding incident. In the past, those animals would have been slaughtered,” Palma said.
Melon-headed whales are considered threatened by the International Union for Conservation for Nature (IUCN) and are protected under Philippine laws.