This photo from the University of the Philippines-Diliman College of Science Marine Mammal Research and Conservation Laboratory shows a spinner dolphin in Tañon Strait.
MANILA, Philippines — Unchecked tourism and overfishing are harming the biodiversity of the Tañon Strait located between Negros and Cebu.
Researchers from the University of the Philippines-Diliman College of Science (UPD-CS) Marine Mammal Research and Conservation Laboratory (MMRCL) issued the warning after it conducted a four-day survey in the area from July 20-23.
Researchers noted the decline in the number of spinner dolphins sighted during the survey period compared to observations conducted in previous years.
“We encountered only between 80 and 90 individual spinner dolphins throughout our four-day survey,” Lemnuel Aragones, head of the UPD-CS MMRCL, said in a statement Tuesday. This is in stark contrast to surveys in previous years, where we might spot as many as 100 individuals in just one day.”
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According to the UPD-CS MMRCL, last month’s survey only revealed three species: spinner dolphins, common bottlenose dolphins, and dwarf sperm whales.
Aragones said the decline may be caused by dolphin-watching boats, part of the strait’s tourism efforts, and a lack of food supply for the dolphins brought by overfishing.
“There should also be a comprehensive assessment of fisheries resources in the entire Strait as there is less food now for these creatures,” he said.
A separate study done by UP Los Baños researcher Maria Kristina Paler showed that microplastics are another threat to the ecosystem of Tañon Strait.
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Based on several studies, when marine animals consume microplastics, it causes problems in their digestive system, eventually leading to health issues in humans who eat these marine animals.
Aragones recommended that the local government place more restrictions on tourism and fishing to protect and preserve the marine biodiversity of Tañon Strait.
In 1988, President Fidel V. Ramos issued Presidential Proclamation No. 1234, declaring Tañon Strait a protected seascape.
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