Latest / How To Protect The Ocean / The Problem with Seaweed Aquaculture: Hidden Threats to Marine Life
Transcript
- 0:00seaweed farms are sprouting up all over the world, offering potential climate, food, and coastal benefits.
- 0:06But a recent warning from scientists says grow too much too fast and we could inadvertently be harming critical marine habitats like seagrass.
- 0:15Today we explore on this how to protect the ocean podcast how this green wave might have a dark side.
- 0:21Let's start the show.
- 0:25Hey everybody, welcome back to another exciting episode of the How to Protect the Ocean podcast.
- 0:29I'm your host, Andrew Lewin, and this is the podcast where you find out what's happening with the ocean, how you could speak up for the ocean, and what you can do to live for a
- 0:35better ocean by taking action.
- 0:37On today's episode, we're going to be talking about seaweed farming and how it could be negatively affecting seagrass habitats.
- 0:44And the one thing that I was talking to a bunch of buddies of mine, colleagues, buddies, they're really good friends of mine, are the Project Seagrass people.
- 0:53They were at UNOC, the United Nations Ocean Conference in Nice, France a couple of weeks ago.
- 0:59And we talked a lot about
- 1:01How seagrass takes a backseat to coral reefs and without seagrasses you don't really have healthy coral reefs and vice versa without healthy coral reefs you don't really have
- 1:09healthy seagrasses they depend on each other same with mangroves all those can be a really good system if everything is healthy and they can secure the coastline offer a lot of
- 1:18biodiversity benefits to each and every one of those habitats because they all play a role but if they're mismanaged
- 1:25then those health benefits and all those biodiversity benefits go downhill and the entire system can be at risk global seaweed agriculture comes into play here as is being pushed
- 1:36because it's been valued at seventeen billion dollars u s in twenty twenty three projected to double by twenty thirty two largely driven by the demand in asia to see we can help
- 1:46with carbon capture
- 1:48fertilizers, food, even renewable plastics, but if it's mismanaged, it threatens vital habitats and biodiversity, just like we talked about for seagrasses.
- 1:58Here's the thing, when you have a seaweed farm,
- 2:00to generate money and offer all these benefits I just talked about.
- 2:04You often put it on top of a seagrass meadow, a seagrass bed, just because it offers that extra health aspect.
- 2:12So usually what was happening is when seaweed farms didn't have seagrass beds underneath, there was a lot of diseases which harmed the actual seaweed and its ability to create all
- 2:23these wonderful things.
- 2:24Scientists started to say, hey, you know what, let's put the seaweed on top of seagrass beds and then the seaweed becomes better.
- 2:30becomes healthier and it becomes easier to work with.
- 2:34The problem is now that seaweed is becoming a huge thing in the market.
- 2:39we're going to see a threat to seagrass beds, which is already starting to see threats.
- 2:44We've had the people from Project Seagrass a number of times on the podcast.
- 2:47Major threats like anchoring boats in seagrass meadows.
- 2:50People don't think seagrasses are a big deal.
- 2:53They're a huge deal.
- 2:54Like I said before, they have a lot of animals that rely on seagrass beds to hide from predators.
- 2:59They rely for food, whether it's the seagrasses themselves or the animals that hide within there.
- 3:04It's a plentiful area and a benefit to a lot of animals.
- 3:08And when you start to scrape
- 3:10anchors or you start to
- 3:12move them around or take them out because people don't want to have sea grasses in their feet when they go in on the beach if they're near a resort or if they're near a popular
- 3:21beach you start to take away the benefits of those sea grasses so we're already seeing a lot of pressure on sea grasses and Project Sea Grass and their partners and their networks
- 3:30are trying to restore sea grasses which is very difficult to do it's not an easy thing to do hasn't been done a lot before there are a lot of projects out there some are successful
- 3:39and some aren't depending on the type of species that they're
- 3:42depending on the environment that they're working in.
- 3:45There's a lot of problems when it comes down to it.
- 3:48And so we need to ensure that seagrass beds and habitats are protected.
- 3:54The ones that are already there are protected.
- 3:57Having this boom of seaweed poses a risk to these seagrass beds because we are seeing like less protection for these seagrass beds.
- 4:05And if you start to push them all in certain areas like Asia and other places, you'll start to see a reduction in the habitat of seagrasses, which is a bad thing.
- 4:16You know, something that could be detrimental to not only seagrass beds in general, but also biodiversity around the ocean and around the
- 4:24world as well as just you know protection for other habitats and health of other habitats and protection of shoreline.
- 4:32So this loss of seagrass meadows because of seaweed farms is not great.
- 4:37and especially in Southeast Asia.
- 4:38these metals, you know, they support fish nurseries, oxygen production, sediment stabilization, and farming infrastructure can smother and damage the seagrass habitat.
- 4:48So it's not always great.
- 4:50Other risks are nutrient imbalance and pollution.
- 4:52Rapid growth may deplete nutrients.
- 4:55When that happens, artificial fertilizers may be used, raising neutrophilication, algal blooms, oxygen depletion, and so forth.
- 5:04of course is also invasive species in genetic spread so farms can introduce non-native species or varieties and diseases escape spores may alter local dynamics if you take
- 5:14seaweed from one place and you start to grow it in another place with oftentimes aquaculture does like liquid it does for the atlantic salmon it'll take atlantic salmon
- 5:21from the atlantic and it'll grow it in the pacific as it provides
- 5:25better habitat for that and a better area for that.
- 5:27So imagine doing that with seaweed, your spores of seaweed that gets into a new habitat or a new environment that becomes invasive that can take over the area and it can cause more
- 5:36damage to the area, including seagrass beds.
- 5:40And of course you have coral competition.
- 5:42in tropical seas, dense seaweeds can directly harm corals through shading, chemical warfare and space competition.
- 5:49So seaweed can be harmful to a lot of places.
- 5:52So having this widespread push
- 5:55for seaweed farming needs to slow down there needs to be precautions that are taken in this is what we do as humans as a population we start to look at one solution like all
- 6:05this is a great solution let's push it to the maximum and less ramp it up and let's do it as much as we can and then we do it we start to realize that there's some damages that can
- 6:15happen let's not look at the ethics before happens and
- 6:18when we look back at it, need to say, look, these are the ethics that we need to think about.
- 6:23We need to go through it as a precautionary approach.
- 6:25Just like we're talking about when Dr.
- 6:26Andrew Thaler was on the podcast talking about the opportunities that we have with deep sea mining.
- 6:31This deep sea mining will probably go through in some cases and in some places, but we have an opportunity to do what's right.
- 6:37We have an opportunity to regulate the heck out of it, making sure that we are protecting the environment while doing it and going slowly and making sure that we are doing what is
- 6:46right.
- 6:47Same thing with seaweed farming.
- 6:48We need to proceed with caution.
- 6:50Do study pilots.
- 6:51Make sure they go on for years and make sure we are looking at how this affects seagrass habitats as well as a seaweed as a product and making sure that we're protecting it.
- 7:01Also, just looking at, hey, you know what?
- 7:03Maybe we shouldn't put seaweed farms everywhere we see seagrasses because seagrasses are important and we know that the seaweed farms can actually harm the seagrass beds.
- 7:13It's hard to say both of these.
- 7:14So that could be a big problem.
- 7:17These are something that we have to see.
- 7:18So some real world examples are having Southeast Asia and the Western Indian Ocean.
- 7:22Some farms have outright replaced seagrass habitats, which is not good.
- 7:26And in the UK, murrel beds, ancient red algae formations, are being smothered by fast growing farm species fostered by nutrient runoff.
- 7:34So obviously not a good thing.
- 7:36Now the upside is, seaweed does help remove nutrients from coastal waters, use and integrate it in multi-trophic systems.
- 7:43to treat ocean to you trophic water so there are some benefits to it as some farmers have turned sargassum overgrowth into simple products such as fertilizer you know building
- 7:52materials and even feedstocks so there are some benefits that's key here is it proceed with caution this is something that we say with everything just like i said when we bring
- 8:02things up too quickly
- 8:04things get out of hand.
- 8:05So the expert takeaways and guidelines scientists argue that we need zoning to avoid sensitive habitats and nutrient budgeting before scaling up the farms.
- 8:14Proceed with caution, just like I said.
- 8:16Regulations should restrict non-native strains and mandate monitoring and adaptive management, and then learn from shellfish aquaculture, riparian buffer zones, and
- 8:26integrated systems to design low-impact seaweed farms.
- 8:30There are ways to go about this the right way.
- 8:33pushing this and ramping up too fast where there's no guidelines or the guidelines aren't being followed can really damage seagrass beds for the long term.
- 8:41And that's not what we need.
- 8:42There are not enough seagrass beds around.
- 8:44There's not enough money put into the restoration and protection of seagrass beds.
- 8:48They are a habitat that is vulnerable to not only extinction and extirpation in certain areas, but degradation and just bad health is really what it comes down to.
- 8:59So, seaweed farming is not the silver bullet, but when guided by smart science and regulation, it can be powerful too.
- 9:05I highly recommend that they team up with seagrass scientists and making sure that things are done science-based and the decision-making is science-based and the management is
- 9:16science-based.
- 9:16Do get the theme here?
- 9:19Science-based rules.
- 9:21This is what we need to do when we go forward with seaweed farms.
- 9:24We're not saying that seaweed farms are bad.
- 9:26But when you start to put seaweed farms over seagrass beds every single time, and that starts to be widespread and scales up, that could be detrimental to seagrass beds,
- 9:34detrimental to biodiversity, detrimental to shoreline security, and detrimental to the ocean in general.
- 9:39Let's ensure we harvest solutions without uprooting the foundations of marine life.
- 9:45That's really what it comes down to.
- 9:47I'm gonna stop it there.
- 9:48I'd love to hear your thoughts.
- 9:49Do you think that seaweed farms should be scaling up?
- 9:53without any of these guidelines or how do you think these guidelines should be implemented?
- 9:57Should they be mandatory in different regions of the world?
- 10:00Love to hear your thoughts.
- 10:01You can hit me up in the comments below.
- 10:03If you're listening to the audio podcast, you can hit me up on the websites, go to speakupforblue.com forward slash contact, fill out the form.
- 10:09It goes right to my email or you can DM me on Instagram at how to protect the ocean.
- 10:14And if you want more ways to guide you to better ocean action, join the undertow, go to speakupforblue.com forward slash join the undertow.
- 10:22That's speak up for blue.com forward slash join the undertow.
- 10:26I want to thank Dr.
- 10:28Benjamin Jones and Dr.
- 10:29Richard Unsworth for writing this article in the conversation.
- 10:31I'm to link to that below and I want to thank you for joining me on today's episode of the how to protect the ocean podcast.
- 10:36I'm your host, Andrew Lewin from the true north strong and free.
- 10:39Have a great day.
- 10:39We'll talk to you next time and happy conservation.