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Voyage to the Central American Dome, the Forgotten Sea

By Erick Ross Salazar, MarViva MarViva Foundation and Mission Blue have teamed up to seek protection for a high seas “hope spot” called the Central American Dome (CAD). A term coined by Mission Blue founder Sylvia Earle, hope spots are areas of particular conservation concern beneath the waves. The Central American Dome is a biodiverse,...

By Erick Ross Salazar, MarViva

MarViva Foundation and Mission Blue have teamed up to seek protection for a high seas “hope spot” called the Central American Dome (CAD).

A term coined by Mission Blue founder Sylvia Earle, hope spots are areas of particular conservation concern beneath the waves. The Central American Dome is a biodiverse, nutrient rich area located hundreds of miles off the coast of Central America. Most of it lies in international waters, outside of national jurisdiction.

Here, a fantastic range of organisms emerge from the depths. Phytoplankton and zooplankton populations, cornerstones in the marine food web, proliferate here due to some unique oceanographic features. They in turn attract a rich diversity of marine animals that come to feed, grow, and reproduce in the area. Blue whales, leatherback turtles, sardines, anchovies, sharks, manta rays, billfish, and tuna are a just a few of the many species that utilize this rich habitat.

Photo: Central American Dome Map (c) MarViva
Dome map (c) MarViva

The CAD is not a fixed area. It’s dynamic, constantly changing its size and position governed by the intensity and direction of winds and oceanic currents. Securing protection for any high seas area is a complex task involving multiple governments and stakeholders, and nowhere is it more true than at the Central American Dome Hope Spot.

The Missing Link

At Playa Grande, in the Las Baulas National Marine Park, Costa Rica, enormous efforts are underway to protect leatherback turtles. The protection of critical leatherback nesting beaches, reduction of poaching and increased collaboration between governments, scientists, and local communities, all work together to improve the one in 1,000 chance of hatchlings reaching adulthood. Every little bit helps for baby turtles that face 50 percent mortality in their nests. Their struggle is made even harder by native and introduced predators, and other human development impacts, including beach erosion, pollution (light, noise, and solid waste), and climate change.

Photo: Leatherback Hatchling © KipEvans /MB/MarViva
Photo: Leatherback hatchling © KipEvans /MB/MarViva

Although egg harvest has been curtailed at Playa Grande, the most important nesting beach for the species in the Eastern Pacific, annual counts of nesting females continue to decline, plummeting from around 1,500 individuals twenty years ago to 22 and counting this season.

The slow recovery of these turtles is largely a consequence from the impacts of intensive egg harvesting during 15-20 years of 90 percent plus take. There is also higher mortality because of more old turtles in the population. The fact that the Pacific leatherback takes 20+ years to reach reproductive maturity is another factor that makes a long-term conservation approach critical. Unfortunately the impacts of egg harvest and beach development have been compounded by dangers from fisheries in both coastal and offshore areas–now the single largest threat to this population.

George Shillinger, a leatherback researcher and scientific director for the Central America Dome Expedition, notes, “The continued survival of eastern Pacific leatherback turtles will require a ‘life-history’ approach. Governments must collaborate to develop management strategies that will protect turtles during all life stages, from the nesting beach to the high seas, linking together the most important marine habitats (juvenile dispersal and nursery areas, migration corridors and foraging grounds) across the range of this magnificent and imperiled species. For highly migratory species such as the eastern Pacific leatherback, these conservation efforts necessarily connect the Pacific coast of Central America with the Central American Dome.”


With a goal to raise awareness about the plight of leatherback turtles and other marine creatures who live in, or migrate through the Central American Dome Hope Spot, MarViva, Mission Blue, Lighthawk, and The Leatherback Trust joined forces to create a short documentary on this iconic and endangered species.

Photo: Sylvia Earle with Hope Spots Map (c) Kip Evans/MB/MarViva
Photo: Sylvia Earle with Hope Spots Map (c) Kip Evans/MB/MarViva

The expedition to film these amazing animals started with a press conference in San José, Costa Rica’s capital, where Sylvia Earle showed her support for this recently named Hope Spot, with government officials and NGOs in attendance.

The expedition team soon headed to Playa Grande searching for leatherbacks. They joined volunteers and park rangers on night patrols hoping to spot a nesting turtle; sadly they encountered only one female, showcasing the dire situation the species finds itself in.

“The high seas, the area that embraces most of the Central American Dome, is part of the global commons; it belongs to everyone and no one,” Earle said at the press conference. “And presently it’s being exploited disproportionately by a few.

“This is an opportunity to step up and say ‘we care,’ we want governance in the high seas, it’s half of the world… We can do whatever we want out there, use fishing methods that are not legal elsewhere, but we can do it in the high seas because there are no governance policies to help regulate the high seas.”

Night patrols were complemented with aerial and boat surveys of nesting beaches and coastal areas along the North Pacific coast of Costa Rica. Luckily several tracks belonging to leatherback and olive ridley turtles were spotted from the air. Dolphins, as well as manta and mobula rays, were spotted, all of them linked to the CAD.

Photo: Costa Rican Coast (c) Kip Evans/MB/MarViva
Photo: Costa Rican coast (c) Kip Evans/MB/MarViva

Next Steps

This expedition and short documentary are the first steps toward achieving sustainability for the dome, a difficult task when you consider that governance schemes for the high seas are just now being developed.

Next on the agenda is lobbying with Central American countries to place the CAD on their environmental agenda, as well as seeking allies around the world willing to support better management in areas beyond national jurisdiction.

An atlas will be created showcasing the distribution of ecologically and commercially important species like cetaceans, seabirds, sharks, rays, tuna, and marine turtles; the distribution of fish larvae and prey fish; the expanse of human activities; and the fluctuations of winds, productivity, ocean currents, and temperature in the CAD.

“We are determined to promote the conservation of the CAD,” said Jorge Jiménez, executive director of MarViva Foundation. “This vast region has the needed conditions to become a showcase for governance, cooperation, and conservation of high seas resources to the world. We cannot postpone any longer our responsibility to this oceanic region. We understand that it is a complex challenge, but this is the moment to act. Joining forces with other partners makes the task attainable.”

Photo: Leatherback Hatchling (c) Kip Evans / MB/MarViva
Photo: Leatherback hatchling (c) Kip Evans / MB/MarViva

All of this will lead up to a film expedition to the CAD during 2015, when we will seek to generate stronger data on the importance of the dome for endangered species and provide further momentum toward the creation of a management plan for the area.

For more details on the expedition you can check out the Central American Dome website.

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