Scientists spotlight plight of whale shark in South and Central America

Scientists spotlight plight of whale shark in South and Central America
Ecoamericas
,
Trinidad and Tobago

Scientists spotlight plight of whale shark in South and Central America

Dení Ramírez was born and raised in Mexico City, but she and other members of her family were avid scuba divers who often spent vacations exploring the Caribbean. In 1998, when she was 20 years old, she moved to La Paz, capital of the Mexican state of Baja California Sur to study marine biology at the Autonomous University of Baja California Sur. There, she met and fell in love at first sight with the whale shark (Rhincodon typus), the world’s largest extant fish.

She asked her professors for information on the shark, which is found in tropical waters around the world, but discovered there was a dearth of research on the enormous, filter-feeding fish, which can grow to over 12 meters (39 feet length) and live 60 to 100 years. Since then, Ramírez has become one of Latin America’s foremost whale-shark experts.

As such, she has borne witness to disturbing whale-shark population declines in recent years—decreases that prompted the International Union for Conservation of Nature (IUCN) in 2016 to declare the giant fish “endangered.”

Since 2003, Ramírez has directed whale-shark research and conservation for ConCiencia México, or Mexico ConScience, a Baja California Sur-based environmental group. Her current research focuses on three areas of the Gulf of California where whale sharks gather every year from October to April to feed, mainly on plankton.

The sharks, which can spend 20 hours a day near the water’s surface and are harmless to humans, attract thousands of tourists who not only observe them, but also swim with them. Recognizing that the species is migratory and conservation efforts must be pursued along its entire route, Ramírez has spent time assembling a whale-shark research network in and beyond Mexico.

“We’ve established an alliance with researchers in other parts of Mexico and in Peru, Hawaii [and] Venezuela, and now we’re doing it in Ecuador, but in the Americas we’re still in diapers when it comes to understanding [the shark],” she says. “We know, for example, that the whale shark exists in Brazil, but there is no data. In Colombia, study is barely underway. On the coast of Belize there were whale sharks, but no longer, probably because they fed on eggs of fish that have disappeared due to overfishing.”

Adds Ramírez: “The whale shark has great tourism-development potential because it is a charismatic species that represents an opportunity for local communities. In La Paz (in Baja California Sur), which historically has attracted divers, we have 20 years of viewing and swimming with whale sharks.”


Victims of crisis

In July, Ramírez took part in a whale shark workshop for biologists attending the first-ever Latin America and Caribbean Congress of Conservation Biology, held in St. Augustine, Trinidad and Tobago. Discussion highlighted the need for cross-border initiatives such as educational-cooperation agreements, a focus of particular interest in the Caribbean, where some countries lack university marine-ecology curricula. Participants were alarmed to learn from Venezuelan biologists that whale sharks in that country’s waters were being caught for human consumption as a result of the ongoing humanitarian crisis there.

“We knew of four cases in 2017, but no doubt there must have been more,” Leonardo Sánchez Criollo, a shark specialist with the Venezuelan Institute for Scientific Research told EcoAméricas. “Unfortunately, the [conservation] efforts made in other countries go to waste in Venezuela and also Haiti, where last year there were at least two cases [of humans killing whale sharks for food]. Hunger means that fishermen that didn’t use to consume this species now do. In Venezuela the whale shark is not protected, and none of our efforts to persuade government officials to [establish protections] have produced results.”

Sánchez Criollo says that given these circumstances, conservationists are working directly with Venezuelan coastal communities. “We have spoken with fishermen who killed whale sharks, and discussed the possibility of developing ecotourism activities,” he adds, “but the critical situation Venezuela is going through makes things difficult.”

In Peru, a July 2017 resolution of the country’s Production Ministry prohibits whale-shark fishing and requires that whale sharks netted unintentionally must be released immediately. The regulation largely reflects advocacy in Peru by ecOceánica, a Peruvian nonprofit that was founded in 2009 and has worked closely with ConCiencia México researchers.


Locating populations

“We were surprised to learn of many cases of incidental [unintentional] fishing of whale sharks, so four years ago we began using fishing boats to look for concentrations [of whale sharks off the Peruvian coast],” says Dení Ramírez, who collaborates with ecOceánica. “The search was pretty frustrating at first, but finally last year we found them near Máncora, in the north of the country.”

Adds Ramírez: “[Peruvian] fishermen have made changes and rescue [whale sharks] caught in their nets. We think viewing and swimming with whale sharks can be a good economic option for local communities if it is done in accordance with conservation norms.”

At the Gulf of California’s La Paz Bay, a recently updated management plan overseen by Mexico’s Environment and Natural Resources Secretariat (Semarnat) allows up to 83 vessels to conduct whale-shark viewing and swimming activities for tourists.

That’s according to Nezahualpilli Tovar, a marine biologist with Tiburón Choyero, an association of tourism operators in the region. Tovar says that among other requirements, the management plan allows up to 14 whale-shark tourism trips at one time in areas where the fish concentrate, and requires that they keep a minimum of five meters (16 feet) from the fish. 

“Up until six years ago the whale sharks of La Paz Bay were in danger,” Tovar says. “Due to a lack of regulation, many tourists came with their own yachts and didn’t know the rules, and we found that as many as 60% of the animals had bruises and cuts. Ultimately, we made a very big effort to organize community oversight in partnership with Semarnat, and today we can say that the whale shark is protected.”

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