DR MARSHALL AND THE MANTAS The scientist bringing a ray of light to endangered marine life
Fishing methods must change if the mantas off Mozambique are to survive, writes Alexander Matthews
WE surge between the angry grey sky and the angry grey sea and then the engine cuts. “Manta!”
My heart leaps and topples — and it is not just the swell. After a fortnight, it’s my second last day in Tofo. Perhaps I’ll finally see one. The dive instructor points; the boat curls round — but there is nothing, nothing. We carry on towards the dive site.
My bum perches on the edge of the boat, an oxygen cylinder is harnessed to my back. As butterflies flutter, I tighten the straps and weights, tugging on flippers and mask. Final checks, a countdown, and I flop backward. As I fall towards the seabed, hope rises. Today will be the day.
But it is not. As our fingertips cling to coral, a current buffets our progress. We glimpse a moray, a few brightly coloured fish. But no mantas.
A decade ago this would’ve been startling. Tofo Beach, a laidback village six hours’ drive northeast of Maputo, has long been considered one of the best places in the world to see manta rays, along with other kinds of marine megafauna — whale sharks, bottlenose dolphins, loggerhead turtles and humpback whales.
These graceful giants brought the California-born scientist Andrea Marshall here in 2003. She has lived in Tofo, on and off, ever since, her research revealing a new manta species and earning her National Geographic Emerging Explorer status in 2013. Alarmed by the decline in numbers, she founded the Marine Megafauna Foundation with whale shark researcher Simon Pierce; together, they aim to research and help to conserve the world’s largest sea animals.
“When I first moved here you had like over a 90% chance of seeing mantas,” Marshall says. Often you saw six to eight of them at a time and sometimes as many as 40. Today, the chances of seeing one — just one — are far, far slimmer. “This used to be one of the greatest populations in the world and in the future I might not be able to show my daughter a manta here. That’s what drives me,” she says.
I didn’t come to Tofo with the intention of learning how to scuba dive, but quickly realised I didn’t stand a chance of seeing a manta if I didn’t. And so I spent three days training with Nick Bateman of Peri-Peri Divers.
A diver since the age of 12, it was witnessing 18 mantas on one of his first dives off Tofo that inspired him to move here from Joburg. “It just blew my mind,” he says. “Diving still blows my mind, that’s why I’m still doing it, but it’s sad to see these mantas slowly dwindling. Last year there was a four-month period without seeing a manta.”
A study by Marshall’s foundation estimates that divers coming to Inhambane on manta ray tours earn the province’s roughly 20 dive-operators $10.9fishers million (about R145-million) a year, while the broader economic impact is a whopping $34-million a year.
The biggest culprit in the decline of manta numbers is fishing. While it’s difficult to gauge the impact of big commercial fishing boats far out at sea, the foundation’s monitoring of artisanal fishing along the Inhambane coastline suggests that between 25 and 75 mantas are caught by small-scale a year. At one time Marshall estimates there were about 1 400 in the area, but because mantas give birth only once every several years (and the young don’t always survive), removing as few as 50 a year over a decade can easily wipe out a third of the population.
After several years of intense lobbying by the foundation, the Mozambican government is due to declare mantas a protected species this year.
But although local fishers will eat them (or sell the gill rakers which are as prized as much as shark fin is in East Asia), most aren’t trying to catch mantas deliberately. The gill nets that have become popular in the last 10 years are indiscriminate, snaring fish, mantas, humpback whale calves and much else besides.
More than half of Mozambicans depend on fish for protein and half a million rely on it to earn a living. A ban on fishing wouldn’t work, so Marshall’s foundation is working with fishing communities to establish “locally managed marine areas” by the end of next year that will allow fishing to continue in a more sustainable way.
Eight “ambassadors” are currently training in alternative selective fishing techniques that they will share with their fellow fishermen in an effort to improve yield and reduce by-catch.
THE sun is back, sparking against the yawning swell as we lurch towards land. It’s my last day in Tofo after two weeks and I’ve just completed my final dive. We checked out Manta Reef — but the site failed to live up to its name. But instead of thinking about what I have not seen, I’m thinking about what I have seen. Down below: honeycomb eels, fish that looked like lions and scorpions, angels and zebras. At the surface: a loggerhead turtle happily bobbing; a super pod of 100 or so bottlenose dolphins that slid around us on en route to my first deep dive. They were back today, one coming so close I could’ve lent down and touched it.
I came to Tofo looking for mantas, but discovered a whole world. I felt changed. And I still have hope. Tofo’s four dive centres have agreed to the foundation’s proposal that fishing and diving at two reefs be suspended for six months to see if that will help to rejuvenate the ecosystem and encourage mantas to return (studies show dive tourism can significantly affect mantas’ behaviour). The agreement to close the reefs is unanimous — good news, as local fishermen have agreed to the closure only if diving stops too.
Perhaps the next time I come, I’ll get to see my manta.
‘In the future I might not be able to show my daughter a manta here’