MAYA BAY, Thailand, March 27 (Reuters) - On any given day in Thailand's Maya Bay, up to 40 blacktip reef sharks cruise in the cyan shallows while about 4,000 tourists visit its white-sand beach flanked by towering cliffs. Marine researcher Metavee Chuangcharoendee said that thanks to the pause in tourism the island was once again functioning as a nursery for young sharks. A number of factors affect the sharks around Phi Phi Leh Island, including seasonal movement patterns and human activity like fishing, Metavee said. For Phi Phi Island National Park, annual revenue was almost halved from 638.3 million baht ($18.7 million) in 2018 to 373.6 million baht in 2019 after authorities closed the beach. "If you can create a new image of Maya Bay as a nature reserve ...

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