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How 5 billion sea stars died and what we can do to save them · How To Protect The Ocean

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  Since 2013, researchers have noticed a drastic decline up to 90%
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  decline in sea stars starfish along the west coast of North America.
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  Nobody really knew what was going on.
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  There was this idea of a sea star wasting disease where they would
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  just waste away and just like, kind of like tear apart underwater.
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  And the ramifications were drastic.
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  We saw an increase in sea urchin populations because of a decrease in
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  the sea stars, as well as a decrease in kelp because urchins eat kelp.
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  There are huge ramifications in finding out what has caused the
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  decline of the sea stars and what we need to do to bring them back.
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  Luckily, researchers have figured out what the actual cause of the sea star wasting
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  disease and now we're hoping to be able to fix it and get that ecosystem back intact.
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  We're gonna talk about it all today on this episode of the How
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  to Protect the Ocean Podcast.
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  Let's start the show.
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  Hey everybody.
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  Welcome back to another exciting episode of the How to Protect the Ocean Podcast.
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  I'm your host, Andrew Lewin, and this is the podcast where you find
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  out what's happening with the ocean, how you can speak up for the ocean,
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  and what you can do to live for a better ocean by taking action.
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  On today's episode, we're gonna be talking about sea stars, including the
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  drastic 90% decline in sea stars since 2013 because of sea star wasting disease.
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  It's a disease that basically broke down sea stars across the west coast of North
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  America, and it caused a lot of panic.
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  There was people running what's going on.
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  During that time, we saw El Nino and the blob, which was, you know,
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  El Nino caused a lot more sea surface temperature increased.
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  There was the blob, which was like a blob of water that was just
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  heating up from the North Pacific.
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  And it was coming down towards the mid Pacific, I guess mid Eastern Pacific.
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  And people said, well, maybe it's because of that.
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  Maybe there's something in the water that's increasing because of this
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  increase in temperature and it's causing like a lot of the parts of the
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  ecosystem to kind of go out of whack.
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  So it's not surprising that sea stars would actually have a problem and
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  maybe they're just melting away.
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  We didn't really know.
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  Scientists were trying to figure out for years.
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  And it has come to my attention that they've actually
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  figured out what's happened.
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  They've identified a bacterium, and I'm gonna try and pronounce this
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  bacterium, but we'll see what happens.
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  Vibrio pectenicida strain, FHCF-3 as the cause of the sea star wasting disease.
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  SSWD that has been devastating sea star populations along North
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  America's west coast since 2013.
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  So like I said before, the disease led to the loss of up to 90% of the
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  Sunflower Sea Stars population equating to over 5 billion individuals leaving
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  the species critically endangered.
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  This is the thing, what happens when you have climate change, when you have other
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  factors that are cumulative that can be very hospitable to other organisms.
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  This bacteria potentially has been doing really well in higher temperatures.
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  It's been proliferating and it's been going all over the West coast
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  of North America, and affecting the Sunflower Sea Star population,
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  making them critically endangered.
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  Like, think about taking 5 billion individuals out of a population.
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  It's critically endangered.
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  We're lucky that it had such a high population.
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  It didn't go extinct.
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  So researchers confirmed the causation by isolating the bacterium from their fluid.
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  So it's almost like their blood fluid, their sea star blood,
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  essentially what we call it.
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  And fulfilling Koch's Postulates via controlled infection study.
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  So this is just the method that they used.
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  And the consequences have included a dramatic surge in sea urchin
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  populations, which has in turn led to the destruction of kelp forests, a key
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  marine habitat for, you know, supporting biodiversity, coastal protection, carbon
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  sequestration, and local communities.
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  Now, just to kind of take it out a little bit and, look at
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  an overview of a kelp forest.
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  Kelp forest are aquatic plants that grow underneath the surface of the ocean.
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  And they stem, like all the way from the bottom.
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  It could be like a hundred meters, 200 meter.
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  I don't know even know if it goes that far.
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  But it goes pretty far up.
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  It's secured at the bottom of the ocean, and then it goes
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  all the way up to the top.
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  And you know the forests are dense forests where you have a lot of cover for animals.
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  And if you go to any aquarium, Monterey Bay Aquarium, you can go to the Toronto
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  Aquarium here locally here in Toronto, and you can see these kelp forests and what it
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  creates, the environment that it creates, all these fish and invertebrates are
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  almost like made to be hidden within this kelp forest.
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  And it's something that is extremely important to a lot of
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  fisheries along the West coast.
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  you know, just sustainable populations and making ecosystems, structure
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  and security along that coastline.
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  There's a lot of stuff that's benefit to that and I remember in university.
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  I'm going back to my university days 'cause my daughter's going to
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  the same university this year that I went to, my wife went to, and I'm
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  going back to my university days and I'm remembering population of
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  Ecology and learning about food web systems and how when you take out a
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  important animal within a species, within a food web, that it affects the rest
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  of the food web and it can affect the dynamic and the balance of that ecosystem.
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  And what I learned was, you know, urchin, sea otter and kelp forest relationship.
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  And so when the sea Otter population dwindled, and it went to critically
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  endangered back in the 1800s and 1900s and there weren't
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  any protections for sea otters.
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  The kelp forest declined because the sea urchin population increased.
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  Well, now we've had some success in seeing the sea otter population increase.
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  And over time we've seen the sea urchin population decrease a little
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  bit, but unfortunately, what we didn't really know is the amount of
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  effect of sea stars on sea urchins.
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  They also eat sea urchins, and the disappearance of these sea stars have
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  shown that there's still an increase, even though the sea Otter population
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  is doing fairly well or doing better.
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  Maybe not at what it once was, but doing better.
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  Even with the sea otter population there, they're not eating enough sea
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  urchins to control the level predation of sea urchins on kelp forests.
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  So I hope this is not too confusing 'cause I'm using a lot of things here.
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  I should probably have a diagram maybe when I get paid to do these types of
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  videos, we can put a diagram together.
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  but essentially what happens is even though you have sea otter population
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  doing better than what it was.
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  You don't have that sea star population, and they both predate on sea urchins.
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  Now the sea urchin population is increasing a little bit and affecting
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  the kelp forest population, which affects so many other species within the west
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  coast of North America that it becomes a negative effect on the entire west coast
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  and affects, you know, coastline security.
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  It affects biodiversity, it affects fisheries, affects a lot of things.
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  and having, you know, cumulative effects like climate change and maybe
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  bad management of fisheries in certain situations and other things, and just
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  coastal development and so forth.
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  You have problems.
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  So the fact that we have diagnosed the problem that's happening with the
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  Sunflower Sea stars and other sea star populations, we can do better now.
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  So with the pathogen now identified.
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  Efforts can shift towards a targeted recovery such as captive breeding,
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  probiotic treatments, and monitoring environmental drivers like warming
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  waters that influence disease outbreaks.
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  So now we know when the water's warm, we can actually detect how badly this
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  bacterium will do, and we can start looking at experiments like that.
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  So graduate students, if you're looking for a project, this would
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  be amazing to do because you're on the forefront, on the cutting edge
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  of looking at how to manage this bacterium and how to manage a critically endangered
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  population and try and bring it back, which seems to perforate quite a bit
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  if it's healthy because there was 5 billion individuals that were killed
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  and it's still critically endangered.
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  So there's a big upside in bringing these species back if
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  we can control this bacterium.
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  So that's the episode.
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  I'd love to hear what you think about this is the fact that it took us so long.
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  Why did it take us so long?
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  I'd love to hear your questions or comments.
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  Let me know in the comments below, if you're watching this on YouTube.
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  If you're listening to this on the audio version, you can get
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  in touch with me with two ways.
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  You can go to speak up for blue.com/contact and you can email me.
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  Just fill out the contact page or if you want to connect with me over Instagram,
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  just DM me at how to protect the ocean.
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  I would love to hear from you and if you want to learn more about how you can
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  better protect the ocean, don't forget.
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  You can join the undertow at any time.
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  We're coming up with this app.
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  It's an online digital app to essentially bring together people
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  who want to do better for the ocean.
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  So not only do we have this community here, but it's also we have this community
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  on this app that you can learn how and be guided to connecting to the ocean.
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  Be with a community that wants to do better for the ocean.
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  And essentially take part in conservation projects or learn how to
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  fund conservation projects, identify by, you know, through vetted processes
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  of what products to use and so forth.
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  There's a lot of upsides, so go to speak up for blue.com/join the undertow.
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  I wanna thank you again for joining me on today's episode of the How
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  to Protect the Ocean Podcast.
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  I'm your host, Andrew Lewin from the True Nord Strong and free.
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  Have a great day.
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  We'll talk to you next time and happy conservation.