Science Friday - Eating More Oysters Helps Us—And The Chesapeake Bay

Episode Date: April 10, 2024

The Chesapeake Bay produces around 500 million pounds of seafood every year, providing delicious blue crabs, striped bass, oysters, and more to folks up and down the coast. It’s one of the most productive bodies of water in the world, but the bay is constantly in flux due to stressors like overfishing, pollution, and climate change. But scientists have a plan to conserve the bay’s biodiversity, support the people who rely on it, and keep us all well fed—and it involves oyster farming.On stage in Washington, D.C., Ira talks with Imani Black, aquaculturist, grad student at the University of Maryland Center for Environmental Science, and founder of the nonprofit Minorities in Aquaculture, as well as Dr. Tara Scully, biologist and associate professor at George Washington University. They discuss the bay’s history, the importance of aquaculture, and how food production and conservation go hand in hand.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Oysters are tasty, if you're brave enough to eat them, that is. But they're also environmental powerhouses. An adult oyster filters 50 gallons of water a day. It's Wednesday, April 10th, and you bet your bottom dollar. Today is Science Friday. I'm Cy-FRI producer Kathleen Davis. The Chesapeake Bay produces about 500 million pounds of seafood every year. It's one of the most productive.

estuaries in the world. It's home to striped bass, crabs, and of course, oysters. But the bay is constantly in flux due to overfishing, pollution, and climate change. Ira Flato speaks to two experts about conserving this important body of water with a plan that involves you eating more oysters. Let's take a listen live from the George Washington University. Okay, you like to applaud. This is good because I want a round of applause. how many of you have eaten striped bass fresh from the Chesapeake Bay? Yeah? How about blue crab?

And in fact, the bay, this is amazing, produces around 500 million pounds of seafood every year. It is one of the most productive bodies of water in the world. But yeah, you can applaud your bay. But if you live here and you know this, the bay is constantly in flux due to overfishing, pollution, climate, change, you know the works that's going on over the year. And scientists have a plan that will conserve the Bay's biodiversity, support the people who rely on it and keep us all well fed. And one piece of the solution is oyster farming. Let's hear it if you love oysters. You want to see it. Great. My next guest are here to discuss the Bay's history and how food production and conservation go hand in hand. Let me introduce them.

Imani Black, aquaculturist and grad student, the University of Maryland Center for Environmental Science. She also founded the nonprofit minorities in aquaculture. Dr. Tara Scully, biologist and associate professor right here at the George Washington University in Washington, D.C. Welcome to Science Friday. Yeah, thank you for having us. Thank you for having us. I hear that, Imani, that you in Chesapeake Bay go way back. Is that right?

Tell me about that. Yeah, something like that. Well, I grew up on the Asian shore of Maryland, and so I just have been around the Chesapeake Bay for a while, but in my family's genealogy, we can trace back Waterman in our family to the early 1800s. Wow. Yeah, long time.

Skipped a few generations before it got back to me, but yeah, you know, we still brought back full circle. And Tara, what about you? So I haven't lived here my whole life, but I grew up in Connecticut. I'm one of nine kids, and I have 28 first cousins, and I think that growing up, the most important thing to our family

was getting out into nature, especially my mom and dad who are in the audience. They brought us across the street to go collect blueberries and to go collect little head ferns, and we had a huge urban garden back when urban gardens weren't a thing. I then moved to New Orleans and got hooked.

I got hooked on looking at the natural environment and seeing how we're impacting it. I had an amazing professor, Dr. White, who was so impactful that when I moved here, I wanted to do something. And actually I owe it to my brother, Sean, who actually said, we should do something. And I was like, yeah, you're right, we should do something.

And so I started working with the Chesapeake Bay Foundation. And so that's how I got involved. Did you actually move on to the bay? Well, we have a family house down there. And so we started to help the Bay by growing oysters ourselves, but donating them back to the Chesapeake Bay. Foundation for their programming. Now, Imani, you've worked on an oyster farm before. Yeah. How do you take care of a bunch of oysters? What do they want? Well, really, they're just glorified

rocks. Like, they don't really give you a fuss. They don't really give you a fight. So they're pretty easy, especially in their adult stage. So my experience, I have experienced from all the way from the beginning when they're babies until they're on your dinner plate. But they're really wanting to have good water quality, good salinity, good food access, right? So we choose to eat microalgae. So that's always available in the water, but especially during the summertime. They're filter feeders. Yeah.

So they filter the water. They do. They clean it. Yeah. Wow. And then you eat the oyster that's filtered out of all that stuff out of the water. Yeah, we get that question. a lot, but they only, they, they kind of break down the particles. And so by the time that they

get into their digestive tract, they're not harmful anymore. Let me ask you, because I think a lot of people may be wondering, what's the difference between an oyster and a clam? Because they, you know, they're both shellfish. They are bivalves, so we don't have a prop. So it's a certain group of organisms that they form a shell that have a hinge to them. And so they have a soft body inside, yes, it's a glorified rock to a certain extent, but inside all of them are filter feeders as bivalves. And so they're the ones doing the job. Oasters, mostly because their population is so huge in the bay. And historically, they're the ones who have been the dominant species that is the filter feeder. How does the oyster market for oysters compared to

other seafood like striped bass, things like that, Imani? Yeah, we were, We were just talking about this offstage, and it's actually like one of the highest, right? Yeah, so in comparison, pound per pound, the oysters actually go for about the same amount of money, but most of the oyster men are now farming. So they're doing aquaculture instead of taking the oysters from the natural environment. And so that means that the natural populations are still there to filter, whereas for the striped bass, we're taking the natural population out of the bay. And so that affects the other organisms in the bay.

because it's a food web and they're part of that food web. You mentioned how good that the oysters are at filtering, Tarak. How much water do they filter a day? An adult oyster filters 50 gallons of water a day. 50 gallons? 5-0, yes. And that's a 2-inch oyster, 2-3-inch oyster. It's not that big.

Yeah, it's not big at all. Any way to come up with a wild guess of how many oysters there are in Chesapeake Bay? Well, I know that it's right now it's at 1 to 2% of the highest ever counted. So it's a very low population in comparison to historically. But the good news is in the past two years, we've seen the counts of juveniles go way up. They're at four times the amount that they have been in the average of the past, I think it's 38 years. And why is that? Because of restoration.

Yeah, restoration, oyster farming. So, yeah, let's give a round of applause for the oyster, yeah. There's a lot of efforts that are happening right now, and there's a lot of misconceptions about aquaculture and oyster farming in general, but it actually just like Tarr said. No, you can't say that without telling us what the misconceptions are. Well, okay, so, I mean, I think that for oyster specifically, because there's multiple different sections of aquaculture,

but for oysters specifically, I've heard that they're genetically modified, that we put harmful chemicals in them and different things like that. And so I'm here to set the record straight by just saying that it's natural selection. We just pick the best ones that survive in the saltier environments or the less salinity environments or the more brackish environments. And we just keep breeding them. So they're really like families that we get really good viable oysters that are actually susceptible to the common oyster diseases. Years ago, I would never have thought you could have conspiracy theories about oysters, but these days, anything. Yeah.

What else, Tara, do they do for the Bay besides clean it up? Well, they're also a foundation species, and what that means is that they establish a habitat for all the other organisms in the Bay. Just like a coral reef, I think the oyster reefs are more amazing than coral reefs. I know that they get their prettier or whatever, but they do support an entire habitat for different. organisms to come and breed, to come and live. There's even like the most amazing crab ever called the ghost crab that lives inside the shell with the oyster but doesn't harm it and actually helps to protect it. And it's really neat.

And so there's a lot of different organisms that rely on the oysters in order to survive. Are there like oyster reefs? Yeah? Like to protect the shorelines like coral? Yes. So Manhattan used to be surrounded by oyster reefs. The whole island was surrounded. But, of course, that's not really good for shipping and development.

So over the years, just like down here in the Bay, they destroyed all the reefs because, you know, they needed to get access to the land. And the population now, as you say, is healthy. It's on the increase. It is. It's not, I mean, we're about to get from the Chesapeake Bay Foundation our new, I think they do it every two years, the state of the Bay report. And I'm hoping that it's going to show that we're definitely coming back. and recovering from a lot of the issues that we have caused. But the Chesapeake Bay Foundation, the Oyster Restoration Program,

all of these different organizations have gotten together in a coalition to help to place reefs in different tributaries that they think are important to restore. And I think now they're up to nine out of 11 targeted for 2025. And so they're hoping to get all 11 by the end of 2025. Wow. Wow, that's great. Now, Imani, I know that you're wrapping up your master's thesis. Congratulations.

Yeah. Thank you. Everybody's rooting for you. What are you studying? So I am studying ecological anthropology of the Chesapeake Bay. So specifically, I'm interested in how socially and culturally we've changed on Chesapeake Bay and how that relates to what's happened ecologically. So specifically my title, or not the title, but just the overall,

topic is the historic African-American contribution in Chesapeake Bay commercial fisheries because our indigenous tribes were a huge part of creating the commercial fishing industry and so we're African Americans and so for a very long time it wasn't a high commodity to live on the water is actually a poor man's thing to live on the water and eat seafood and because of the enslavement era African Americans were pushed to the water's edge and so you know historical folks that we know Harriet Tubman, Frederick Douglass, actually use their maritime skills of being on the water to escape slavery. So it's been a huge significant piece of our cultural heritage as African

Americans. And so there's a lot of documents, people, accomplishments that have not been told before. And so I'm hoping to do that with my thesis. Has there been a decline in African-American oyster? Yeah. So there's actually only 12. Only 12. Living black captains on the Chesapeake Bay today, and they're all over the age of 60, with no real push for the next generation to come behind them right now. So right now it's said that I am the only African-American female to be working in oyster farming from Maryland to Texas, which is insane.

Insane. Wow. When did we see that exodus from the business? Well, you've got to wait for my thesis because that's like the chunk of it. I can't, yeah, that's the whole thing. Yeah, yeah. Send us a copy. Tara, is there a new wave, Tara, in aquaculture happening now?

As things on the increase? Well, I think there's not only a new wave, it's a new thinking around the ownership of the land. I think a lot of oyster men originally thought they owned the space where the oysters were growing. Nowadays, like the Rappahannock Oyster Company, which were two cousins who had parents who were both, oyster men, they went to their parents and they're like, listen, we need to do things differently. We can't keep on doing things the same way. So they really focused on doing aquaculture instead of harvesting, even though they could, they had the rights to do it. And now they're a huge company and they're very successful. And I think that that's the wave that we're seeing is more young

people want to get into this type of either vertical or horizontal type of aquaculture. It's much easier and it's not having that negative impact on. the environment, and even it's helping because you have those filter feeders in the water that are helping to filter. I was just about to say one oyster farmer annually puts out two million individual oysters a year. So, and imagine we have like thousands of oyster farms in the Chesapeake Bay. And so even if those oysters are in the water for a week or a day or whatever, they're still filtering 50 gallons of water a day. So oyster farming is actually kind of really helping in that, you know, really getting them back into filter feeding. We talked about conspiracy theories about what's going on with oysters.

But can Tara genetically engineering make the oysters grow more efficiently? Well, we have actually Dr. Allen who just, he retired, I think three years ago, yeah, from the Virginia Institute of Marine Science. He actually created the original triploid oyster. Triploid oyster. And what that means is you have three sets of DNA. You and I and Amani all have two sets from your mom and dad. But the way he did, he did several different techniques, but ultimately what he did was he figured out a way to have a tetraploid,

which has four, and then a diploid have a baby. And it's because the tetraploid can give two sets of their chromosomes, and that's male, and then the female gives one set, and then you have a baby that has three sets. And so the reason why that's important is because they're infertile, which sounds weird, but this means that it grows faster. It's not susceptible to disease like the normal oyster is. And it grows to market size much quicker because it doesn't have to reproduce.

So the reason why you can't eat oysters during the months without an R is because they're putting all their energy into making sperm and eggs. And so they shrink up and they're making their sperm and eggs and they don't taste as good. These, you can eat all year round. And so that's another benefit of aquaculture. Are they actually growing now? Yep, yeah. Yeah. Wow. And hopefully they'll take over more of the population.

Well, these are the aquaculture oysters. These are the ones that we're growing in aquaculture. I see. And Imani, what inspired you to get into writing your thesis and founding minorities in agriculture. Yeah, well, I didn't expect to do either, but 2020 had different plans, and so I just kind of took the opportunity. I wasn't expecting to do it at the same time, but they sort of kind of cascaded. And I really kind of, after being an oyster farmer for six years before starting both, I had to be really intentional about, well, I've got this beast of a train that's moving on with

minorities and agriculture. I need to think of a thesis project that is really going to tie into that. you know, I can be efficient on reading. There's a lot of reading in the master's program. So I was just trying to cut that down in half, really. Well, I was going to ask you how fast you can chuck an oyster, but I'm going to... Oh, I got a video in the back. You want to see? It's like five seconds. Five seconds.

Yeah. I'm not the... I'm not... I can't do that consistently. Like, I'm not doing any shucking contest. But, I mean, I was just saying to Tara, I should have had, like, a little basket of shells. I should have just, like, been... Anybody want to shucked them and throwing them out there. Wow.

Wow. I can be efficient when I need to be. I'm afraid to ask this next question now, but what do you want our audience to take home tonight to know about their seafood? What should they take home in the message? Yeah, I think for me, just like know where your seafood is coming from, right? Local seafood is how you become more sustainable. That's like the buzzword with people in our food security is sustainability.

The way to be more sustainable with your seafood, one, eat more oysters. oysters are the most sustainable protein on the planet compared to beef, chicken, all the things. So, eat more oysters. Second, just know where your seafood is coming from. Get it from a local source, you know, really shake hands with that person so that you can say for yourself that you understand how it's being produced, how it's being harvested, and you can be okay with that, and you can support that in any way that you want to. Great final message. I want to thank both of you for taking time to be with us today.

Yamani Black, aquaculturist, grad student, University of Maryland, Center for Environmental Science, and Tara Scully, biologist, associate professor at the GWU here in D.C. Thank you, again, both for coming here. And that's all the time that we have for now. A lot of folks help make the show happen, including... Rasha Auretti. D. Peter Schmidt.

Sandy Roberts. Shoshana Buxbaum. And many more. Tomorrow, we'll put on our detective hats and take a behind-the-alli. the scenes look at what happens when an animal dies at the Smithsonian Zoo. But for now, I'm sci-fry producer Kathleen Davis. Thanks for listening.