While many fear sharks, they are an important part of our oceans' ecosystem. Marine scientists are studying how the food these predators eat can be seen as a litmus test for the health of the oceans. Elizabeth Cook reports.

Sharks play a crucial role in regulating ocean food chains, making them important indicators of marine ecosystem health. Scientists from Oregon State University are studying sharks in Willapa Bay, Washington, analyzing their diets to assess the condition of the local environment. By examining what sharks eat, researchers can determine if the ecosystem is healthy, as apex predators reflect the overall state of the food web.

The research team has studied hundreds of sharks in the area, focusing on species like the broadnose seven gill shark. Their findings suggest that a healthy shark population points to a healthy bay, which is vital for local communities that depend on fishing. Despite public fascination with sharks, funding for such research remains a challenge.

How sharks help determine the health of our oceans

Sharks are among the top predators in the animal kingdom who help regulate the complicated food chain in our oceans. Marine scientists are studying how the food they eat can be a litmus test for the health of our oceans. Our Elizabeth Cook hopped aboard a ship in the Pacific to show us. Oh my gosh, there he is. Pulling a seven foot long shark out of the water turned out to be a lot easier than you might expect. Hey, look what I caught. Marine scientists from Oregon State University do this so they can study them and learn from them. I got you. I'm gonna crank him up just a touch. Hi. Dr. Taylor Chappell directs the university's big fish research program. Whether this male is mature or not. So what kind of shark is this? So this is a broadnose seven gill shark. He doesn't seem to mind that you're doing all these things to him. They get pretty chill when they're on the boat. Yeah. So we've got an aerator coming through. So right now he's calm. So your job, so you're gonna take your hand. You're gonna hold his nose right here. Okay. These fish, sharks, are the best way to understand not just how they live, but where they live. A healthy shark means a healthy ocean. I got it all under control. Don't worry. Don't worry. Oh my God. Good, you got it. Nice. Dr. Chappell and members of the university team have studied 350 sharks in this one bay. Total two, two, one. Willapa Bay in the state of Washington, just north of the Oregon border. There are 15 different kinds of species in and around the area. Now, why this species right now? So seven gills are really an indicator of the health of your ecosystem and the ones that maintain and manage the ecosystem. Sharks are an apex species, meaning they are at the top of the food chain. If what they are eating is healthy, then that is an indicator of the health of the water. And that matters too for many of the people who live here and depend on fishing for their livelihoods. So we'll actually collect the stomach contents from the individual shark. Part of the examination Jess Schulte will do is figure out what the sharks are eating. She is working on a PhD on sharks diet. And today, another shark. They're also generalist predators. So they'll eat basically whatever's in front of them. Even if it's another shark. Even if it's another shark. Back in the lab, what they learn from the shark is analyzed. We've actually got a jaw here of some animal. No surprise, this is a healthy shark. Has it been difficult to get people to care about sharks because of frankly the bad rap they've gotten over the years? Yeah, people are interested in sharks. They like to watch a show about sharks. But when it comes to people opening their wallet to support the research, it's really, really difficult. But because of what he and his team have been able to do here, they can say this one bay is healthy. You're free buddy, you did great. Elizabeth Cook, CBS News, Willapa Bay, Washington.

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