09/09/2016

Is a Seaweed Boom a Boon?

5:28 minutes

Seaweed farming at Uroa, a fishermen village in Zanzibar. Credit: Moongateclimber (Own work) [Public domain], via Wikimedia Commons
Seaweed farming at Uroa, a fishermen village in Zanzibar. Credit: Moongateclimber (Own work) [Public domain], via Wikimedia Commons

Seaweed is trending. Demand for the fast-growing, nutrient-rich food is on the rise, and what’s not being eaten is now used in everything from skincare products to pharmaceuticals and industrial adhesives.

In 2014, the seaweed industry was worth more than $6 billion, and today, farms of cultivated seaweed continue to spread off the coasts of China, Korea, Indonesia and elsewhere. But while seaweed’s popularity brings with it plenty of economic and nutritional benefits, a new report from scientists at the United Nations University cautions that the way we’re farming the crop may be putting our supply at risk.

“Many countries such as Korea and Japan and China, Indonesia, the Philippines … have benefited from seaweed farming for hundreds of years, and they’re doing very, very well,” says Elizabeth Cottier-Cook, a marine biologist for the Scottish Association for Marine Science and the report’s lead author. “It provides very poor, rural communities with an excellent income.”

And in the last decade, rising demand for seaweed has also opened new production markets in places throughout Canada, America and even Scotland. As crops go, seaweed isn’t fussy: One variety native to Indonesia and the Philippines is now grown in over 30 countries.

“It’s really easy,” Cottier-Cook says. “You just propagate it like you would some of your plants. You take a cutting, and then you can move that cutting to any place in the world where it’s likely to grow, where the temperature is right.”

Despite the ease with which the marine algae can be transplanted, Cottier-Cook warns that doing so is still risky business. Seaweed cuttings from other farms can harbor ‘hitchhikers,’ or pests and pathogens that may also thrive in a crop’s new location.

And as with other crops, seaweed’s growing global monoculture also warrants caution. Between 2011 and 2013, the Philippines lost a seaweed harvest worth $310 million to ice-ice disease, a bacterial infection that causes part of the plant to bleach itself, and die, as if turned to ice. With so little biodiversity between farms, the disease spreads like a deep freeze.

“You can lose your entire crop very quickly because of course, [the plant] is just a clone,” Cottier-Cook says. “It’s got the same genetic makeup throughout the entire farm. So one plant gets infected, and that’s it.”

To stave off a global seaweed crisis, the United Nations University report recommends that seaweed farmers embrace a hard-won lesson from other farm industries: Cultivate more varieties.

“One of the recommendations we really called for, as well as improved biosecurity on your farm, is actually to produce far more cultivars of the seaweed, [with] different genetic makeups,” Cottier-Cook says. “So you have seed banks ready, so if a farm fails you’re ready to supply it with a new cultivar — the same species, but of a slightly different genetic makeup that may well be resistant to that disease.”

—Julia Franz (originally published on PRI.org)

Segment Guests

Elizabeth Cottier-Cook

Elizabeth Cottier-Cook is a marine biologist for the Scottish Association for Marine Science in Oban, Scotland.

Segment Transcript

IRA FLATOW: Now it’s time to play “good thing, bad thing.” Because every story has a flip side.

And here’s something you might not have known. Seaweed farms– seaweed farms– are doing brisk business. Demand for seaweed as food is growing. But so is its use in skincare products, industrial adhesives, and even landscaping. The industry was worth more than $6 billion in 2014 and farms of cultivated seaweed continue to spread off the coasts of China, and Korea, and Indonesia, and many other countries.

So where am I going with this? Well, there’s some good and some bad news in this story. And a new report from scientists with the United Nations University have some warnings for the burgeoning industry. The lead author of that report is my guest, Elizabeth Cottier-Cook is a marine biologist with the Scottish Association of Marine Science, head of the UN University Associate Institute in Scotland. Welcome to Science Friday.

ELIZABETH COTTIER-COOK: Hi. Hi. Thank you so much for having me on your program.

IRA FLATOW: You’re welcome. Well, let’s talk about this. How do you farm seaweed to begin with?

ELIZABETH COTTIER-COOK: OK. Well, typically, you kind of stretch some lines out and you buoy them so they’re sort of floating on the surface of the sea. And then you have other lines that are hanging sort of vertically down from beneath that, in which you attach your tiny, tiny little [? spawlings, ?] your tiny plants. You’re attach them maybe in your nursery or hatchery, and then you put it out to sea and then they grow into these beautiful, long seaweed plants.

IRA FLATOW: Dr. Cottier-Cook, who is benefiting from seaweed farming?

ELIZABETH COTTIER-COOK: Oh. Of course, many countries, such as Korea, and Japan, and China, Indonesia, Philippines. All of these countries have benefited from seaweed farming for hundreds of years and they’re doing very, very well. And it provides these kind of very poor, rural communities with an excellent income.

Of course, in the last 10 years, though, there’s been more and more countries in developed nations– in Canada, America, Scotland even– that have kind of cottoned on that seaweed production could actually be quite profitable. And there’s more and more interest in growing seaweed in these more developed countries. So yeah, there’s quite a lot of interest. And that’s one of the reasons why it’s grown so much over the last 50 years.

IRA FLATOW: Well, it seems like everybody can grow seaweed then and make some money, and feed, and make all kinds of products from that seaweed. What’s the bad side about this?

ELIZABETH COTTIER-COOK: OK. So, yeah. Over the last few years– and this is something that really sparked this report that came out just earlier this week. The seaweeds that are being grown– there’s one in particular, kappaphycus, which is from sort of Indonesia and the Philippines area– that’s now grown in over 30 countries around the world. And this one particular seaweed, it’s really easy. You just propagate it like you would some of your plants. You just take a cutting and then you can move that cutting to any place in the world where it’s likely to grow– where the temperatures are right, of course.

But of course, along with those plants, you can also take disease. You can also take hitchhikers, like pests and pathogens. And we call them invasive, non-indigenous species. So you can take these along with you.

And one of the countries– the Philippines– just between 2011 and 2013, it lost $310 million dollars, just in that two year period, through disease– a disease called the ice-ice disease, which is a bacterial infection. So you know, there are these downsides of cultivation which have been seen in other industries. And the purpose of this report was to, pretty much, what lessons can be learned from other industries that we can apply to the seaweed. Yeah.

IRA FLATOW: Well, what does the ice-ice attack? When you say you they’ve lost all this money. From what?

ELIZABETH COTTIER-COOK: Yeah. It’s the actual seaweed itself.

IRA FLATOW: The seaweed itself?

ELIZABETH COTTIER-COOK: If you looked at the seaweed, it looks like parts of the frond and parts of the seaweed has actually turned to ice. It loses its color. It loses its red coloration. It just turns very sort of opaque white and dies. And you can lose your entire crop very quickly because, of course, it’s just a clone. It’s got the same genetic makeup throughout the entire farm. So one plant gets infected, that’s it. There’s no resistance.

IRA FLATOW: So you need more biodiversity in the seaweed then?

ELIZABETH COTTIER-COOK: Yeah. Absolutely. And that’s one of the recommendations that we really called for, as well as improved biosecurity on your farm, is actually to produce far more cultivars of the seaweed. So different genetic makeups. So you have kind of seed banks ready, so if a firm fails, you’re ready to supply it with a new cultivar. The same species, but of a slightly different genetic makeup that may well be resistant to that disease.

IRA FLATOW: Dr. Cottier-Cook, thank you for taking time to be with us today. Elizabeth Cottier-Cook is a marine biologist with the Scottish Association of Marine Science.

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