All saltwater bodies on Earth form one big ocean. But within that there is infinite variety – just ask any diver. Some places have more coral, more sea turtles, more fish, more life.
“I’ve dived many places around the world, and there are few locations like Fuvahmulah Atoll in the Maldives,” said Amanda Batlle-Morera, a research assistant at the Important Shark and Ray Areas project. “You can observe tiger sharks, thresher sharks, scalloped hammerhead sharks, manta rays and more without casting bait to attract them.”
Identifying areas like Fuvahmulah that are especially important for certain species is a long-standing strategy for protecting endangered terrestrial animals, birds and marine mammals such as whales and dolphins. Now our team of marine conservation scientists at the Important Shark and Ray Areas project are using it to help protect sharks and their relatives.
I am a marine conservation biologist and the project’s communications officer. This initiative works to identify locations that are critical for sharks and rays so that these zones can be flagged for future conservation or fisheries management measures.
Where the sharks are
Sharks and their relatives are among the most endangered animals on earth, with more than a third of all known species threatened with extinction. Many of these animals play crucial roles in their ecosystems. Losing marine predators can destabilize entire food webs and the ecosystems on which those food webs depend.
In recent years, management of sharks and their relatives, rays and chimeras, has largely focused on curbing the impacts of fishing and trade on these species. But their populations are still declining rapidly, so new strategies are needed.
To effectively protect these important and endangered animals, my colleagues and I believe it is critical to identify and protect parts of the ocean, plus some freshwater habitats, that are particularly important to their lives. For example, some areas are important migration routes, or feeding or mating areas, or places to lay eggs.
Our team has developed a list of technical criteria so that zones around the world can be surveyed and potentially identified as important shark and ray areas. We modeled these criteria based on similar approaches already in use, such as Key Marine Mammal Areas, which we adapted to the specific needs and biology of sharks and their relatives.
We are now organizing a series of 13 regional workshops around the world and inviting local experts to nominate preliminary areas of interest for evaluation by our team and an independent expert review panel. To date we have completed three workshops, one focused on the Central and South American Pacific Ocean, another on the Mediterranean and Black Seas, and the third on the Western Indian Ocean, with a workshop for Asia planned to begin 2024.
Following the workshops and expert assessments, each final significant shark and ray area is added to our e-atlas, which can be viewed online. The important shark and ray areas of each region will be published in a formal compendium, and the entire global process will be repeated every ten years. This cycle will allow us to consider changes in areas that have already been mapped, such as new fisheries policies or the impacts of climate change, and take into account new research that can help us identify new areas.
Inform conservation policy
We recently published our compendium for the Mediterranean and Black Sea regions, which includes input from more than 180 experts from across the region. It identifies 65 important shark and ray areas that vary widely in size and habitat type. Our Western Indian Ocean compendium covers more than 125 areas.
These zones are important for species such as the critically endangered blacktail guitarfish (Glaucostegus cemiculus), as well as heavily fished shark species such as the common smooth shark (Mustelus mustelus).
Some of these areas, such as the island of Benidorm off Spain’s Mediterranean coast, are located in shallow coastal areas. Others, like the Cocos-Galapagos Swimway off the coast of Costa Rica and Ecuador, extend into deep ocean waters.
The smallest area identified so far, Israel’s Palmahim brine pools in the southeastern Mediterranean, measures just 0.09 square kilometers – about half the size of New York City’s Grand Central Station. Black mouth cat sharks (Galeus melastomus) breed and lay eggs there, and endangered angular tope sharks (Oxynotus centrina) feed there, also on eggs of blackmouth catsharks.
The largest area is the Strait of Sicily and the Tunisian Plateau, which extends over 200,000 square kilometers (about the size of Britain) in the Mediterranean Sea between Sicily, Malta, western Libya and Tunisia. This zone is home to at least 32 species of sharks, rays and chimeras, including many that are threatened with extinction, in habitats ranging from shallow seagrass beds to deep ocean trenches.
Identifying a location as an important shark and ray area does not mean it is automatically protected. Our aim is to inform countries’ existing land use and fisheries management processes and other conservation planning. Ultimately, these zones may be included in marine protected areas or other types of ocean reserves.
Sharks and their relatives need human help to survive and maintain their important biological role in the ocean. Through the Important Shark and Ray Areas project, hundreds of scientists and other experts are helping to identify special places for these species that we think need some extra attention.
Dr. Rima Jabado, chair of the IUCN Species Survival Commission Shark Specialist Group, contributed to this article.
This article is republished from The Conversation, an independent nonprofit organization providing facts and analysis to help you understand our complex world.
It was written by: David Shiffman, Arizona State University.
Read more:
David Shiffman does not work for, consult with, own stock in, or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond his academic appointment.