” ‘Mantas!’ shouts Guy Stevens from the top deck, pointing to huge bat-shaped shadows gliding under the rippling, turquoise water of Hanifaru bay in the Maldives,” writes Damien Carrington for the UK’s Guardian newspaper.
“Mantas are protected in the Maldives and had been faring relatively well,compared with populations in Sri Lanka, Indonesia and elsewhere, where thousands of the inquisitive creatures are slaughtered each year to supply the Chinese traditional medicine market.
But Stevens is worried by a new threat. Usually about a third of the females are pregnant every year, he says: ‘But then – boom – in 2009 reproduction just stopped.’
‘Is this part of long-term natural cycles or is it something more sinister, related to climate change and human impacts?’ asks Stevens, founder and chief executive of the Manta Trust, which runs its Maldives programme from the Four Seasons resort on Landaa Giraavaru island, with the company funding the Trust’s staff and operations.
‘I suspect it is not natural,’ he says. ‘The meteorological people say the monsoon is changing [from usual patterns], and the fishermen who have been out there for 50 years say it is definitely changing.’
Stevens has been tracking the Maldive mantas for eight years and has 15,000 sightings of 1,500 individuals from the last four years alone. Their feeding events correlate closely with the average speed of the winds, which have been blowing less strongly overall in the past four years.
Weaker winds are less effective at stirring up the seas, meaning the nutrients needed for plankton to bloom are missing. “If primary production is affected, that passes up through the food chain and affects the mantas,” he says, adding that mantas bring in about $20m a year in tourism revenue for the Maldives.”