The Dwindling Sharks and Rays of the Western Indian Ocean

By Rhett Bennett

Sharks have been cruising the world’s oceans for millions of years. We know them as ferocious hunters, built for the kill. And some are. However, most shark and ray species have somewhat less aggressive feeding behaviour and, of course, many end up as food themselves.

These magnificent creatures have adapted to an incredible diversity of habitats, from the open ocean to deep ocean trenches, volcanic seamounts, coral reefs, mangroves, estuaries and rivers. There are even some that have evolved to live exclusively—or almost exclusively—in freshwater environments like the freshwater stingrays in South America and the river sharks in Southeast Asia and Australia.

In the waters off East Africa, in the Western Indian Ocean, nearly 230 shark and ray species have been identified, making this one of a handful of global shark and ray biodiversity hotspots. Because of this high diversity, including several species that are found only in this region, and because shark and ray species are millions of years old, the Western Indian Ocean is considered globally important for shark and ray conservation.

A shark is eviscerated and its fins are removed on the streets of Zanzibar. Photo credit: Rhett Bennett/WCS.

At the same time, in East Africa there are 70 million people living within 100 km of the coastline, many of whom are dependent on fishing and marine resources as their primary form of protein or income. Artisanal and traditional fishers use a range of fishing gears, such as handlines, longlines, spears, mosquito nets, beach seine nets, gill nets and even baited gill nets to target fishes, and many also target sharks and rays.

There are also small-scale commercial, commercial and industrial fishing vessels using deepwater trawl nets, shrimp trawl nets, deepset gill nets, longlines and purse seine nets. The result is that many of these either target—or result in considerable bycatch of—shark and ray species.

This heavy fishing pressure creates a major threat to sharks and rays. Most species grow much slower than other fish species and become sexually mature much later in life. They also tend to have very few offspring. Most will have just five or ten well-developed young per year, compared to some fishes that may release several million eggs in a single spawning event.

Wedgefishes dominate a drying rack. Photo credit: ©Michael Markovina.

While sharks and rays may have evolved the perfect biology to capitalise on all aquatic habitats, their reproductive design cannot support extensive fisheries. Approximately one quarter of the species found in the Western Indian Ocean face a high risk of extinction in the wild due to overfishing. Sawfishes have not been seen in East Africa in several decades.

Fishing of sharks and rays has increased exponentially in recent years, driven largely by the global trade in fins—especially guitarfishes and wedgefishes—to supply the demand for shark fin soup.

It is not only direct fishing pressure that has a negative impact on sharks and rays, but also the destruction of critical habitat. Examples include the burning of mangrove trees to create coal (mangroves provide nursery areas for many species of coastal sharks and rays), destruction of coral reefs for coastal development, and overfishing of fish species that provide food for sharks and some ray species.

WCS staff Dr Rhett Bennett and Katya Kalashnikova prepare to deploy a baited underwater video camera off Pemba Island, Zanzibar. Photo courtesy of Katya Kalashnikova.

A recent status report led by WCS (Wildlife Conservation Society) in collaboration with several other organisations highlighted the key threats to sharks and rays in the Western Indian Ocean. These include directed and incidental mortality in several fisheries, a lack of ecological knowledge and information on catches in the different fisheries, as well as poor controls on trade and a lack of legislation specifically for sharks and rays.

Nevertheless, it is not all bad news for these animals. There has been a new wave of focus on shark and ray conservation in recent years, both globally and within the Western Indian Ocean. Seychelles and South Africa have developed national plans of action, for the conservation and management of sharks and rays in their waters.

In addition, WCS is supporting the Ministry of the Environment, Ecology and Forests of Madagascar and the Kenya Fisheries Service to produce national plans of action for shark and ray conservation and management in Madagascar and Kenya, respectively, while plans are underway to develop a guiding roadmap for shark and ray management in Mozambique, and hopefully Tanzania will follow soon.

A cowshark investigates an underwater camera in a South African marine protected area. Photo credit: Michael Markovina.

WCS has several conservation initiatives in the Western Indian Ocean aimed at addressing the threats to sharks and rays, through collection of ecological and fishery data, supporting governments to develop and implement regulations and legislation specifically for shark and ray species, and through engagement with fishing communities to raise awareness of the poor status of most shark and ray species, and the need for their conservation.

While sharks may kill four or five humans per year, the annual number of sharks and rays killed by humans exceeds 100 million! And most shark attacks are effected by just a few species. Ultimately, sharks and rays support many human activities and contribute essential ecological services, and they have very few negative impacts on humans.

Shark Week reminds us that it is time to improve our knowledge of sharks and rays, and support initiatives to protect these prehistoric species and their habitats, rather than persecute them.

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Dr. Rhett Bennett is Shark and Ray Conservation Officer for Madagascar and the Western Indian Ocean at WCS (Wildlife Conservation Society).

Reducing Manta Ray Mortality in the World’s Largest Targeted Manta Fishery

By Hollie Booth

This Shark Week, take a moment to consider the manta ray. This much-loved gentle giant of the shark and ray (elasmobranch) family is a large, slow-growing and long-lived species, which makes it particularly vulnerable to overfishing.

Unfortunately, fishers have increasingly targeted mantas in recent decades to meet emerging demand for their gills in traditional Chinese medicine markets. This growth in demand is primarily the result of industry marketing, with the gills being peddled by practitioners as a cure for coughs and chicken pox, and for promoting respiratory health.

Left: A tourist admires a manta ray in Indonesia’s Komodo National Park. Photo credit: Hollie Booth/WCS; Right: Indonesian law enforcement authorities seize an illegal shipment of hundreds of manta ray gills. Photo credit: Paul Hilton for WCS.

Indonesia is a global priority for manta ray conservation, as it’s the world’s largest elasmobranch fishing nation and a major supplier of manta ray gills to the world’s largest consumer markets. Indonesia is also home to what is thought to be—or at least was—the world’s largest targeted manta ray fishery: Lamakera.

Lamakera is a small coastal community in Eastern Indonesia made (in)famous by the 2015 Emmy-award nominated film documentary “Racing Extinction.” People in Lamakera have been hunting marine megafauna for centuries, but traditionally the catch was just for local consumption. However, in the early 2000s manta ray catch in Lamakera rocketed, transforming in to a commercialized industry.

Map of Lamakera.

Around 2002, annual landings were as high as 1,000 individuals—a huge mortality rate for such a large, slow-growing species. Catch has declined ever since despite increases in fishing effort: a sure sign of an overexploited population.

Through a collaboration led by Reef Check Indonesia and Manta Trust, a manta conservation project was launched in Lamakera in 2013. This coalition led an intensive scoping and community consultation phase, laying critical foundations for future work by WCS Indonesia and Misool Foundation.

In 2014, the Indonesian Ministry of Marine Affairs and Fisheries declared manta rays a protected species. This was a huge success for elasmobranch conservation (one that provided a clear legal framework for protecting mantas) but a major challenge for implementation—particularly because manta ray fishing is an important part of the livelihoods and culture of coastal communities like Lamakera.

A manta ray fisher expresses his livelihood concerns. Photo credit: ©Misool Foundation.

To address this complex problem, WCS Indonesia and Misool Foundation adopted a multi-faceted approach. We focused on improving enforcement of manta ray regulations while developing incentives for regulation compliance and adoption of sustainable marine management practices—a classic carrot and stick approach. Since then, we’ve been monitoring our data to assess our impact.

What have we achieved so far? Since 2014, WCS has conducted law enforcement trainings on detecting, deterring, and prosecuting marine wildlife crimes, while supporting collection of data on illegal trade and providing legal advice to enforcement officials. More than 20 suspects involved in illegal manta ray trade have been arrested since 2014, with an estimated 4,200 kg of manta ray products seized.

These have resulted in sizeable fines and jail time in the first-ever prosecutions related to protecting fish species in Indonesia. We found there has been a significant increase in average fines and prosecutions for illegal shark and ray traders following WCS trainings for government officials, which we believe is an indicator of improved awareness, motivation, and capacity to prosecute marine wildlife crimes.

LEFT: The WCS and DKP East Flores patrol boat out on the water. Photo Credit: Hollie Booth; RIGHT: Graph by WCS.

Marine patrols were launched in 2016, and increased significantly in 2017, with the timing and location of patrol efforts strategically concentrated in areas and times of highest likelihood of hunting incidents.

On the community level, our partners at Misool Foundation established a sustainable fisheries cooperative. Of 63 members, twenty-two are ex-manta ray fishers committed to cease targeting mantas by participating in the cooperative. The benefits from participation are tied to compliance with manta ray protection regulations. An additional 13 local female manta ray traders have committed to developing non-manta ray livelihoods, and have received small business loans to do so.

Community monitoring of illegal fishing and by-catch incidents has significantly increased. Over the past year we’ve received 33 reports of illegal fishing and accidental by-catch of protected marine fauna, resulting in the apprehension of five illegal fishing vessels and release of 18 protected animals. Awareness of regulations has clearly improved along with local pride in marine megafauna.

Building community pride in marine megafauna. Photo credit: Erma Normai/Misool Foundation.

Most importantly, we are already seeing a measurable impact on manta ray mortality—with a statistically significant decrease in manta ray mortality in 2016/17 we can connect to our dual ‘carrot and stick’ strategy.

Through concerted efforts across different levels of society, WCS and Misool Foundation are achieving a measurable impact on saving manta rays in Indonesia. Behaviour change required for effective conservation can be complicated. Encouraging people to reduce environmentally destructive habits (especially if they have limited options) requires a variety of approaches. Some people will respond well to carrots, and others to sticks.

Despite these successes, pressures, challenges and uncertainties remain. Demand continues to drive hunting of manta rays. The population is severely depleted and recent enforcement measures may have resulted in illegal activity moving to less well-monitored locations. Our successes so far are just the first steps towards achieving long-term meaningful change and holistic sustainable management of marine resources.

Achieving success in the long-term is possible only with flexible, understanding donors and diverse and resilient partners. The financial support of  the Shark Conservation Fund and The Paul G Allen Family Foundation/Vulcan has been critical, just as we have relied on the skill and commitment of Misool Foundation, the East Flores fisheries authority, and the water police.

Establishing and maintaining change takes time (especially when there are strong a persistent drivers for illegal targeting and trade), but based on our success so far we feel confident that time is on our side in protecting these extraordinary species.

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Hollie Booth is Sharks and Rays Advisor for Southeast Asia at WCS (Wildlife Conservation Society).

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