Manny Mogato, PlanetArk 12 Feb 09;
PILAR - Dozens of Philippine fishing boats tried to stop hundreds of disoriented dolphins from beaching themselves near the mouth of Manila Bay on Tuesday, officials said.Inspector Edgardo Bernardo, police chief in Pilar town in Bataan, said many of the dolphins were found in shallow water and some had come ashore, including three in a bad condition due to wounds.
Malcolm Sarmiento, head of the fisheries and aquatic resources bureau, said experts were studying whether an underwater quake had disoriented the animals or the pack of dolphins followed a sick leader.
"Many strange things are happening in our oceans now and we still don't have any explanation for these occurrences," Sarmiento said.
(Editing by Rosemarie Francisco)
Why those dolphins beached themselves
Capt. David Williams, Special To The Manila Times 12 Feb 09;
Several hundred dolphins entered Manila Bay on Tuesday. Never before had so many dolphins been seen in one group in the Philippines. I can explain why these animals visited the area in such great numbers.
Dr. Malcolm Sarmiento Jr., the director of the Bureau of Fisheries and Aquatic Resources, announced on television that a “seaquake” might have caused the stranding. He was right. I developed the Seaquake Theory in the early 1980s and published a 106-page report dedicated to the US Marine Mammal Commission entitled “Auditory Trauma as the Major Factor in Whales and Dolphin Strandings” in which I showed how undersea earthquakes injure pods of whales.
The US government was not ready in the 1980s to talk about auditory trauma in dolphins and whales, so my work got swept under the rug so to speak. Even today, most scientists find it difficult to comprehend earthquake-associated injury in whales because they apparently do not appreciate the intensity of pressure changes in the water above the epicenter of a potent seaquake.
Rest assured, diving-related injuries from undersea disturbances are a hundred times more common than today’s scientists can even imagine. They have closed their eyes so tightly to pressure-related auditory trauma that they often become angry at the mere suggestion that an undersea earthquake could cause injury in a whale. This is so because most governments and naval establishments do not want the scientists they support with grant money to talk about such things as deafness and barotrauma in marine mammals because of implications that sonar and oil-industry airgun arrays might also do the same thing. They have been able to suppress the truth by selectively funding scientists who are willing to look the other way in exchange for a grant. Most scientists know the truth. If they come out in support of pressure-related sinus injury in whales, they will be blacklisted by government funding agencies in the United States, the United Kingdom, Australia and Canada. Just asked the ones on the side of the whales in the recent battle over sonar use. They know that they will likely never get another government-funded grant.
Undersea quakes to blame
Regardless of what scientists might say, the pod of melon-headed whales (dolphins) on Manila Bay were injured by a rather nasty group of more than 120 undersea earthquakes. The swarm started with a small magnitude-4.5 event on December 21, 2008. Things got red-hot on January 3, 2009 when a magnitude-7.6 event erupted near the water’s edge on Papua Island in Indonesia, 700 miles southeast of Davao City in Mindanao. The 7.6 magnitude quake was followed by more than 120 major aftershocks each one capable by itself of inflicting injury on a pod of dolphins.
Just as it would be if a large group of Navy scuba divers were suddenly exposed to rapid pressure changes from explosive depth charges, a pod of feeding dolphins caught off-guard by rapid and excessive changes in the surrounding water pressure during a series of potent thrusting earthquakes are subject to barotraumatic injury in their heads and middle ear sinuses when the rapid changes in pressure exceed the dolphins’ ability to adjust.
The volume of air contained in each sinus cavity is in direct proportion to the surrounding water pressure. As the pressure increases, the volume decreases. As the pressure decreases, the volume increases. The dolphins can normally deal with a certain amount of pressure change, but, on occasion, a major disturbance on the seafloor, a volcanic eruption or a meteorite impact sends intense waves of changing pressures over the entire pod. The fluctuations in pressure come too fast and are too excessive, causing the volume of air in the sinuses to expand and contract to the point of injury, thereby disabling the entire pod at the same time. Sinus injury would naturally disrupt feeding and diving because of extreme pain.
Sensitive air sacs
Of particular concern to whales and dolphins are the small air sacs (pterygoid sinuses) that surround each inner ear and help the dolphins sense sound direction underwater. These air sacs bounce sound waves around inside the dolphins’ heads in a fashion so that they can determine the direction from which the signals originate. The first symptom of a damaged pterygoid air sac is the lose of echonavigation and echolocation. Additionally, biosonar requires two balanced ears so even a slight injury to one air sac will knock out echonavigation.
To repeat, oscillating pressure changes in the water above the epicenter of an undersea earthquake or volcanic eruption causes the volume of air in the head sinuses to expand and contract excessively resulting in a pressure-related injury (barotrauma) that interrupts diving and causes biosonar failure. An earthquake-injured dolphin could hear sounds perfectly well, but would not be able to determine from which direction the signals were coming.
I have found that often it is not just one seaquake that causes the stranding. Of the several thousand beachings I have studied over the last 40 years, more than 80 percent were associated with a swarm of 10 or more earthquakes as was the case for the recent event on Manila Bay.
Recovery time
Some pods recover within a few days. Others within a few weeks. Those that do not recover stand an excellent chance of beaching or being culled by sharks.
The swim path of the injured pod is determined by the surface currents. Common sense says that the flow of the water offers many times the resistance when swimming upstream as it does when swimming downstream, thus the lost pod is stirred by reduced resistance into the fastest downstream flow where it remains until some other factor causes it to change direction. Of course, the pod can and often does use its excellent vision to help guide it, especially during the day. This explains why dolphins usually go ashore at night when they can no longer see the bottom.
The pod on Manila Bay was first carried east of Papua Island and away from the Philippines by prevailing surface currents. The dolphins then encountered a counter-current that carried them north for a few hundred miles and then northwest to a point north of Samar Island. The fast current flowing through the San Bernardino Strait directed the pod to the Ticao Pass around Ticao Island and into the Sibuyan Sea. The surface currents then carried the pod through the narrow Verde Island Passage and past Balayan Bay and into Manila Bay by way of the South Channel on a rising tide. I am certain that this route will be verified by local fisherman who surely saw this large pod moving toward Manila.
That the dolphins were milling around Manila Bay was a dead giveaway that the current at the time was calm, as can be verified by pictures of small boats near the dolphins.
When the current picks up, a lost pod will swim downstream in the path of least resistance. Current is what builds the beaches so the odds are good that the pod could be directed to a sandy spot somewhere nearby. If the current carries the dolphins back out to sea on a falling tide, they are subject to return on the next rising tide. If winds remain as predicted, the pod will slowly leave the coast and head out to sea toward China and the Gulf of Tonkin. If they survive for another week, they will strand somewhere near the Chinese island of Hainan. Likely, they will not survive more than another week.
Final words
In summary, my Seaquake Theory indicates that barotrauma, as a result of exposure to potent earthquake-induced changes in ambient pressure, solves the centuries-old mystery of why whales and dolphins mass-strand on beaches around the world.
Forty years of experience tells me it is too late to save the dolphins that were stranded on Manila Bay. They had been at sea for over 30 days without fresh water and food. They were weak and likely had a large parasitic burden and were unable able to rid themselves of these worms unless given large doses of antibiotics, which could have damaged their sensitive ears, resulting in fatal hearing impairment. Bottom line is that at this point, the dolphins that beached themselves on the bay stand zero chance of recovery.
Editor’s note: Capt. Williams is a 67-year-old retired marine mammal researcher now living in Dumaguete City, Negros Oriental. He was a commercial sea captain for 40 years and has been very active in whale conservation since he was 14 years old. He said he has been “obsessed” for more than 50 years trying to understand why whales and dolphins strand themselves.
Marine mammal studies pushed
Alexander Villafania, The Inquirer 11 Feb 09;
MANILA, Philippines – Tuesday's stranding of an unusual number of melon-headed whales in the coast of Pilar, Bataan should spur the government to pursue more studies on the country's marine mammals, an expert said Wednesday.
The Philippines does not have comprehensive data on marine mammal ecology, Associate Professor Lemnuel Aragones of the University of the Philippines Institute of Environmental Science and Meteorology (UPIESM) (http://www.iesm.upd.edu.ph/) told INQUIRER.net Wednesday.
Aragones said the comprehensive data was necessary to enable a proper response to the strandings of whales and dolphins that belong to the family of cetaceans.
Nelson Bien, head of the fisheries resource and management division of the Bureau of Fisheries and Aquatic Resources, said that the melon-headed whales or Peponocephala electra are listed under the family Delphinidae, commonly known as dolphins.
The International Union for the Conservation of Nature (IUCN) has listed these whales in its list of threatened species, said Bien.
Aragones, a post-graduate degree on tropical environmental science from the James Cook University in Australia, said it was difficult to get funding from government on marine mammal studies largely due to the lack of economic value from marine mammals.
Aragones noted that the BFAR, a sub-agency of the Department of Agriculture, was the main agency with jurisdiction over marine mammal programs.
He added that the Department of Science and Technology (DOST) was looking into cetacean conservation studies.
He also said there were at least 26 types of cetaceans present in the country, ranging from ordinary bottle-nose dolphins to pygmy blue whales.
Incidentally, Aragones said BFAR, UPIESM, and the Ocean Adventure Marine Park in Subic started the Philippine Marine Mammals Stranding Network (PMMSN) in 2005 as a response to cetacean strandings or beachings.
Aragones cited the PMMSN training received by BFAR officials in Bataan during the mass strandings.
Whale and dolphin strandings are common yet unexplained occurences worldwide but is rare in the Philippines. Aragones said the last mass stranding in the Philippines was in 1956 when around 12 sperm whales were stranded in a coastal area in Capiz.
Incidentally, Aragones said there were at least 10 strandings that happened in the Philippines every year but which involved only one or two animals that were either sick or dying.
The Bataan incident involved at least 300 stranded melon-headed whales (scientific name: Peponocephala electra). The International Union for Conservation of Nature (http://www.iucnredlist.org/details/16564) said the melon-headed whale was widely distributed throughout the world's oceans.
Project Jonah, a non-government organization in New Zealand claims that the largest recorded beach stranding
Read more!