Today is Shark Awareness Day — an occasion to highlight research, promote conservation and dispel fear and myths about these important ocean predators.
There are about 500 different species of sharks, from the world’s largest fish, the whale shark, to the tiny dwarf lantern shark, smaller than a human hand. These animals live in every ocean and in a variety of aquatic habitats, from the deep sea to the open ocean or shallow, coastal lagoons.
But did you know that 25% of shark species are currently listed as endangered, threatened or near threatened by extinction by the International Union for the Conservation of Nature? They face threats due to changing environmental conditions, overfishing, getting caught in fishing gear meant to target other commercial species, and shark finning, which is the process of removing fins from sharks and discarding the rest of the shark back into the ocean.
FAU is home to several shark scientists working to understand more about these misunderstood creatures, to learn more about everything from how they swim to where they migrate. Here’s a look at a few and why what their shark research matters:
- Matt Ajemian, Ph.D., assistant research professor in the FAU Harbor Branch Oceanographic Institute, studies the ecology and conservation of targeted fisheries and vulnerable species, including sharks. He seeks to better understand the behavior and ecology of these species using scientific surveys and electronic tagging techniques to examine how sharks and other fishes respond to natural and anthropogenic changes in the environment. “Our work broadly seeks to understand interactions between sharks and human activities (fishing, nutrient pollution, etc.) as well as their ecological needs,” Ajemian said. “We cannot sustain these populations without this information.’
- Stephen Kajiura, Ph.D., professor in the Charles E. Schmidt College of Science, has studied the annual blacktip shark migration in southeast Florida for more than a decade. He also researches shark sensory biology and is currently examining the ability of sharks to hear low frequency sounds.
“Our work specifically studies the movements of these top-level marine predators that can traverse large distances over the course of the year,” Kajiura said. “This is important because the migratory patterns of these sharks are shifting in response to global climate change. As the oceans get warmer, the sharks are not coming down in the large numbers that they did historically. These sharks can thus be used as an indicator species to reveal the ecological impacts of a changing ocean.”
- Marianne E. Porter, Ph.D., associate professor in the Charles E. Schmidt College of Science, studies the mechanics of how sharks and rays swim and their different swimming styles. “In my lab we study biomechanics, we work to understand how animals function,” Porter said. “And we can also use information we learn about sharks. For example, in my lab we study shark skin mechanics, and these data can be developed into products that can help humans. Shark skin inspired surfaces can help prevent fouling and enhance the flow around objects.”
Here’s what they want you to know about sharks in South Florida.
Ajemian: Sharks are part of the scenery here in Florida and they play varied, yet vital, ecological roles necessary to maintaining the health of our ecosystems. They also support recreational and commercial fisheries, and people really enjoy seeing them under water. There are dozens of species here, and they’re not all out to get you. In fact, they’ve lived here well before any humans did.
Kajiura: Sharks perform a vital role as top-level predators in the local marine environment. Having lots of sharks is indicative of a healthy ecosystem so people should be happy that we have so many sharks visiting us each year.
Sharks are here in South Florida year round, but we have a tremendous influx of thousands of blacktips that migrate down every winter. These sharks are like snowbirds — they come down to enjoy the warm waters of South Florida during the winter months, then migrate back north in the spring. Despite the huge numbers of sharks in South Florida, we have few bites on humans, which illustrates that the sharks are not blood-thirsty monsters out to get us whenever we enter the water.
Porter: We are really lucky to have such great elasmobranch (sharks, skates, rays, etc.) diversity and live so close to the oceans. As scientists, we still have so much to learn about these critters. Elasmobranchs (sharks, rays, and skates) are an important part of our ecosystem.
The reefs that we love to dive and snorkel on are impacted by the presence or absence of sharks and rays that live there. Understanding and conserving Florida sharks and rays will help keep our ocean healthy.