Latest / How To Protect The Ocean / The Pollution That Breeds: How the Great Lakes Stopped Invaders

Transcript

The Pollution That Breeds: How the Great Lakes Stopped Invaders · How To Protect The Ocean

0:00
in 1988 someone found a small stripe muscle in Lake St.
0:03
Clair. and it was about the size of a fingernail.
0:06
Nobody had seen it in North America before.
0:08
And within a few years, there were actually billions of them coating pipes,
0:12
boats.
0:13
And the bottom of the Great Lakes.
0:14
It didn't look good. A lot of the fish populations went down.
0:18
It would like the lakes were changed quite significantly.
0:21
Then the Great Lakes pulled off something that no other freshwater system
0:26
in the world has managed. And that's what we're gonna talk about
0:28
on today's episode of the How to Protect the Ocean podcast.
0:30
I'm your host, Andrew Lewin.
0:32
Marine biologist and science communicator here to tell you
0:35
all about what's happening with the ocean.
0:37
Today we are talking a lot about ~ invasive species,
0:42
right? It's a we're gonna talk about some of the stories ~ that usually
0:46
end in the same way. some something arrives,
0:47
they take over, and then use is like this is here forever,
0:50
we can't do it.
0:51
And you feel helpless because you see these animals here.
0:53
And how are you gonna get rid of them?
0:54
How do we get rid of them in the Great Lakes?
0:56
Like these mussels and other like lionfish.
0:58
How do you get rid of them into the ocean?
0:59
And there's all these things that you you look at and you're my gosh,
1:02
how are we doing? ~ but this episode shows two places where people did push back,
1:06
and the numbers have proved that we can manage some of these invasive species.
1:11
I'm not saying it's easy, but it's something that we can do.
1:15
~
1:16
Just to kind of give you an I an idea,
1:18
like I've been watching the Zebra Mussels for a while.
1:21
This this whole invasive zebra mussels thing since high school.
1:24
So I was in high school in the 1990s.
1:26
they were the poster poster child for it's too late,
1:29
quote unquote, it's too late. And and I've been waiting a long time
1:33
to tell the other half of the story.
1:35
This was something that I did a project on in my science and society class,
1:39
which is one of like my favorite classes looking back at at high school.
1:42
And it it's something that,
1:44
We never really talk about in terms of pollution.
1:49
This is a type of pollution. And we've been talking all about pollution this week.
1:53
We had, the author of the second edition of Marine Pollution,
1:57
Dr. Judith Weiss, who's here to talk to us on Monday about all
2:00
the different types of pollution.
2:01
Then we start to dive in. We looked at sewage in New York Harbor and how it's,
2:04
we stopped the flow and the harbor started to recover.
2:07
~ and recovered. Now we have, a great ~
2:10
organization that's looking at whale counts because the whales are back
2:13
and the Mendaton are back. the next day we talked about on Wednesday
2:16
we talked about drugs in our water like pharmaceuticals.
2:19
to try and stop the dose and and and we see that the the lake can recover
2:23
and we have the technology to do that.
2:25
And then yesterday we talked about plastic and it it only grows when
2:29
we make more and so that we know that we can stop making it
2:31
and everything is better.
2:33
Now, every one of those pollutants needs us to keep adding it,
2:37
right? Like the like plastic, pharmaceuticals,
2:40
sewage, everything is added in there.
2:42
But this one, the biological pollution,
2:45
breaks that rule, right? A chemical spills and gets diluted over time.
2:48
an invasive species as a population gets bigger because it reproduces.
2:53
And that's why like some scientists call invasive species like biological pollution.
2:59
living things in the wrong places and changing the system around it.
3:02
That's what we need to do. So let's let's talk about,
3:06
the zebra muscle situation and how that started and then how we we're
3:10
and getting to the point where what we are doing to really stamp this out.
3:14
Cause I think it's it's really important when we think about
3:17
the ramifications of this.
3:19
So the big cargo ships that you see in at ports carry water in their hulls
3:23
to keep them steady, It's a called ballast.
3:25
So a ship takes on water in one port,
3:28
sails across the ocean, and pumps it out into another.
3:31
So if it arrives in Hamilton Harbor here in Canada in the Great Lakes,
3:34
~ in Lake Ontario, then it will,
3:36
it'll pump out that water. Now
3:40
Not anymore, but it did that's what it did.
3:41
So along with that water comes whatever was living in it.
3:44
So it could be larvae, tiny crustaceans,
3:46
fish eggs, plankton. a ship's ballast tank is is pretty much a free ride across
3:51
the planet. And
3:52
In 1988, a small striped mussel was found in Lake St.
3:56
Clair. It's the little lake between Lake Huron and Lake Michigan.
3:59
And it was a zebra mussel, native to the region around like the Black
4:03
and Caspian seas in Eastern Europe and Western Asia.
4:06
It almost certainly arrived in the ballast water.
4:09
That's what pretty much we have on ocean-going ships.
4:12
it spread pretty quickly. So zebra mussels and their close cousins,
4:15
the quagga mussel, can pack in about 20,000.
4:20
per square meter. That's how that's how close they can get and that's
4:23
how dense they can get. And they're small,
4:25
like they're like the size of a fingernail.
4:27
and at some of the power plants intakes,
4:29
so the pipes that that bring in the water,
4:30
people have counted up to 750,000 per square meter.
4:34
they clog the pipes, jam valves,
4:36
they they damage cooling systems
4:38
I remember I worked for one of my first jobs in private environmental consulting.
4:42
I worked for a company, a wastewater company,
4:45
that would try to get rid had like a type of natural chemical that these erbamos
4:51
didn't like. And they would they would help industry get rid of them from their
4:55
pikes because they would clog them up so much.
4:58
Now, the estimated economic damage in North America since they arrived runs between
5:02
one and one and a half billion dollars.
5:05
that's a pretty large sum of money,
5:06
especially when you look at all the stuff that happens along the Great Lakes.
5:09
And they changed the lakes themselves,
5:11
like completely. A single adult can filter up to two liters of water a day.
5:15
And Lake Erie's muscle population can filter a volume of water equal
5:19
to the whole basin in a single day.
5:21
Now, Lake Erie is not the biggest lake,
5:23
but it's still a pretty big lake.
5:25
And that made the water clear,
5:26
which sounds to be good news. That's great.
5:28
Like it make it nice and clear.
5:30
But clear water here means the plankton at the bottom of the food
5:33
web has been stripped out. There's like a lot of the the brownness or
5:37
the the the murkiness, I guess,
5:39
of the water was plankton. And when you don't have plankton,
5:43
the fish that depend on it, including like the young species like walleye
5:47
and leg trout, pay the price. they're not there anymore.
5:49
And unlike a spill, the mussels
5:52
didn't fade over time. They reproduced every year.
5:55
There were more and more and more.
5:57
That's the type of biological pollution we're looking at.
6:00
It's not like that it dilutes,
6:02
it multiplies. So now let's head south to a warmer water and a fish that's pretty
6:06
beautiful, venomous a little bit,
6:07
and very hungry. it's the stuff that nobody really recognized,
6:11
like lionfish. Lionfish are stunning.
6:14
red and white stripes, long fan-like fins,
6:16
a crown of venomous spines. Like they're pretty cool.
6:19
They're native to the reefs of the Pacific and the and the Indian Oceans.
6:23
And for years, they were a popular fish in home aquariums.
6:27
And in mid-1980s, lionfish started to turn up along the Florida coast.
6:31
And people were like, where did this come from?
6:33
And most likely the explanation is that they were released from the aquariums,
6:36
like the marine aquarium hobby.
6:38
So essentially people had them in the aquariums.
6:41
And they said, what, we don't want them anymore.
6:42
We don't want to ret we're not going to return them to the store,
6:44
which is what they're supposed to do.
6:45
They don't want to kill them. So they release them into the ocean because it's
6:48
the ocean. It's one big ocean.
6:50
This is where they should be. Well,
6:51
yeah, they do belong in the ocean,
6:53
but they're from Indonesia. They're not on the Atlantic.
6:55
They're not in the Caribbean. So since then,
6:58
they've actually spread through the Caribbean,
6:59
the Gulf of Mexico, and the US as far north as Carolina.
7:04
I've gone diving in the Caribbean multiple times and I see them
7:07
on every single dive. It's actually
7:09
Quite insane to see them. The only time I didn't see many of them
7:13
was in Grand Cayman, and that was pre-COVID.
7:16
So that was quite a long time ago.
7:17
Now they had every advantage. A female lionfish can spawn every three to four days,
7:23
releasing more than two million eggs a year.
7:26
their venomous spines mean almost nothing in the Atlantic wants to eat them.
7:30
So there's no natural predators.
7:32
And the native fish had never seen a predator like this before.
7:35
So they didn't know like to swim away.
7:37
So lionfish had been recorded eating like more than 70% of the native species that
7:42
were on there, the native fish that were on there,
7:44
because they're predatory species.
7:45
And in 2008, two scientists from Oregon State University,
7:48
Mark Albans and Mark Hicks, measured just how much damage they do.
7:52
On a small experimental reef in the Bahamas,
7:55
they compared reefs with lionfish to reefs without.
7:58
Over just five weeks, the reefs with lionfish saw about 79% fewer young native fish
8:03
settling into that area. That's crazy.
8:07
Like young fish are like the reef's future and lionfish are eating.
8:10
And I've covered this on Ocean Dakota Live ~ earlier this week,
8:14
where we talked about how if you have a coral reef that is suffering from bleaching,
8:19
having the layers of fish that you need.
8:22
To make sure that there are fish to take off algae,
8:25
to allow young corals to settle after a pretty devastating like
8:29
six month bleaching event or six-month heat wave event.
8:32
It's really important to have those there,
8:35
to have that like layers of fish and and a and a healthy food web.
8:38
If you don't have that, then the coral reefs are not going to be able
8:41
to survive for very long. So now you have like we talked about two invaders,
8:44
right? We two different places,
8:46
very different places, one freshwater,
8:47
one marine.
8:49
And like I want to talk now like how how people are are fighting back,
8:53
because that's really what this comes down to.
8:56
This is not anymore where we're just like,
8:57
hey, these species are here. We're just gonna have to deal with them.
9:00
That was part of it. But there's been research going on for decades
9:03
to kind of figure out how we can get rid of them.
9:05
So between eight 1959 and the mid 2000s,
9:08
the Great Lakes picked up a new invasive species,
9:10
roughly like every six to seven months.
9:12
It wasn't just the zebra mussel.
9:13
Some had more impact than others.
9:15
And scientists have said no other freshwater system on the planet
9:18
was invaded that often. It's almost like a war of the species.
9:22
And it's because, the Great Lakes are such an important navigation area into central
9:27
Canada and the US. Now today there are close to 190 non-native species established
9:34
in the basin. And about two-thirds of the ones that have arrived after 1959 came
9:39
in the ship's ballast water. So Canada and the United States went after the ballast.
9:44
Like that's that's you found the the the problem.
9:46
Now you gotta go after it. So in nineteen ninety-three,
9:48
ships coming into the Great Lakes from the ocean have to swap their ballast water
9:52
out and it's at sea, replacing the fresh or brackish water with salt water.
9:57
So it gets rid of all those animals that were in there.
9:59
And anything that stays around,
10:01
get if they're freshwater, they're gonna get killed by the salt.
10:04
And the idea was simple like freshwater hitchhikers from the from the port
10:07
in Europe usually can't survive a
10:08
With a full strength ocean water.
10:10
And the the early rules had some gaps.
10:13
So ships that said they had no ballasts on board often still carried leftover water
10:18
and sludge in the bottom of their tanks,
10:19
and invasive and invasions kept coming in.
10:22
So between 2006 and 2008, both countries,
10:25
United States and Canada, tightened up the rules.
10:28
Ships had to flush even those empty tanks with salt water.
10:32
And every ship heading into the St.
10:33
Lawrence Seaway would have its tanks checked.
10:35
So they were all inspected. In 2022,
10:38
two Canadian scientists, Anthony Ricciardi at McGill University and Hugh McIsaac
10:43
at the University of Windsor, looked at what happened next.
10:46
They compared three 13-year periods from 1981 to 93.
10:51
19 new non-native species were detected.
10:54
From 1994 to 2006, 26 were detected.
10:58
So obviously that the f now they're gonna have to really flush them out.
11:01
From 2007 to 2019, after the tougher rules,
11:05
just four not native species came in.
11:07
That's an 85% drop. The invasion rate in the Great Lakes is now the lowest it's been
11:12
in two centuries. So we're starting to see some progress here.
11:16
There's still obviously some work to do,
11:18
but there's some progress here in not allowing more in and trying to get
11:21
rid of the ones that are already here.
11:23
And Ricky already put it this way.
11:25
He goes, I'm aware of no other documented case
11:27
In which the invasion rate of a large aquatic system has been suppressed through
11:31
a management intervention. Like the same lesson as New York Harbor.
11:36
Find the door to the problem that comes through and pretty much close it.
11:40
That's the idea, And in 2017, an international treaty on ballast water management
11:44
came into force. So ships around the world now have the to manage their ballast
11:48
water too. So it's not just people coming into Canada or the US or the St.
11:51
Lawrence Seaway. Now closing the door.
11:55
works for new arrivals, but what about the lionfish already here?
11:58
You can't flush an ocean. Like it just doesn't work that way.
12:01
So once the lionfish had spread across thousands of kilometers of reef,
12:06
most people assumed nothing could be done.
12:08
you'll never catch every lionfish in the Caribbean.
12:11
That's just not going to happen.
12:12
And a team led by Stephanie Green,
12:14
~ working with Isabel Cote at Seven Fraser University,
12:17
asked a different question. What if you don't catch every single one?
12:22
they worked on 24 coral reefs near Eleuther Island in the Bahamas.
12:26
On some reefs, divers regularly speared lionfish,
12:29
removing somewhere between 75 to 95% of them.
12:32
enough to keep their numbers below the level where they start to wipe
12:36
out the native fish. Others were left alone.
12:38
The results came out in 2014 on the reefs where lionfish were kept low.
12:43
native prey fish numbers went up by 50 to 70 percent fish that matter
12:47
to local fishers like nasal grouper and yellow tail snapper they came back
12:51
too and Stephanie Green summed it up like this by creating safe havens small pockets
12:56
of reef where lionfish numbers are kept low we can help native species recover
13:01
and we don't have to catch every lionfish to do it
13:05
And that idea caught on. So in Florida,
13:07
the state now runs a lionfish challenge.
13:09
In 2024, 285 divers removed 31,773 lionfish.
13:15
Holy cow. The highest total since the challenge started in 2016.
13:21
One diver speared 915 by himself.
13:24
And the lionfish ended up on restaurant menus,
13:27
where it turns out like they're quite delicious.
13:29
I've actually had them before.
13:30
They're they're they're quite meaty.
13:31
Noah has even promoted eating lionfish as a way to help control them.
13:35
we are very good at overfishing.
13:36
Overfishing an invasive species,
13:38
it's not a bad thing. So the thing is,
13:41
I think what I want you guys to keep in mind here is you don't need
13:45
to completely win. Keeping an invader low gives the local ecosystem time to recover.
13:50
But the thing is, like ballast rules close one door and
13:54
There are still others that are still open,
13:56
right? You have recreational boats moving between lakes,
13:58
aquarium and pet releases, bait buckets,
14:01
and invasive carp moving north through US rivers.
14:04
And there are programs out there to try and keep them out as much as possible,
14:09
but we can't control everything.
14:11
Like zebra and quagga mussels aren't leaving the Great Lakes.
14:13
They're still there. The wind is keeping them from reaching new lakes
14:17
and keeping new species out. They're even
14:19
Have been experiments to try and keep them out of smaller lakes and even just like
14:23
eradicate them from smaller lakes by dosing the lakes.
14:26
I don't know the exact chemical to use,
14:28
but it's usually natural and it doesn't affect the rest of the lakes because they
14:31
do a lot of studies around that.
14:33
Now lionfish aren't leaving the Caribbean either.
14:35
They're gonna be there. The wind is managing them reef by reef.
14:38
So it's all gonna be down to local management and whether the local authorities
14:42
or the countries or the islands that are around there have the ability
14:45
and the resources to do this type of stuff.
14:48
And it's like this is where where you come in,
14:50
I mentioned earlier, if you have a boat and you're going from lake to lake,
14:54
which is fine. I want we want people to be on lakes.
14:56
But the thing is you should clean,
14:58
drain, and dry every time you move a boat,
15:01
canoe or kayak, anything, or a paddle board even,
15:04
from one lake or river to another.
15:06
Sometimes it just takes a couple of larvae pieces to attach onto
15:09
a paddleboard and then it goes into another lake and it starts to
15:12
it starts to invade that lake,
15:14
Clean off any kind of plants, mud.
15:17
Anything struck under the hull or a trailer,
15:19
Drain all the water, anything that will go into the water,
15:22
like clean them off, drain all the water,
15:24
including the bilge and live wells.
15:27
Let everything dry before you launch somewhere new.
15:29
And in Ontario, it's it's pretty much the law.
15:31
Since January 1st, 2022, you have to remove aquatic plants and animals
15:37
and drain the water before you move the boat overland.
15:39
Fines could run up to at least $350,
15:42
which doesn't sound like much,
15:43
but for a recreational boater,
15:44
you don't want to have to pay that much.
15:46
we saw a zebra mussel spread from the Great Lakes to inland lakes,
15:50
largely on boats and trailers.
15:51
And the ballast ruse close the big door,
15:54
they're less likely to come in through through the ports.
15:57
you clean, drain, and dry, that closes the small ones.
16:00
you're the one who's who's holding them shut.
16:03
Like we want to close these doors.
16:05
We want to close these areas that they can come in.
16:07
Now, this week we had five episodes.
16:09
The first episode was all about the different types of pollution.
16:12
Then we broke down four different types of pollution,
16:14
Sewage in New York, drugs in the lake,
16:16
plastic in Canada, invasives in in the Great Lakes.
16:20
Obviously, a focus on Canada because I'm Canadian.
16:22
I'm I'm close to these ~ ideas,
16:24
but this is happening all around the world.
16:25
And the pattern is pretty much every time.
16:28
We find where the problem comes from,
16:30
we act on it, and give nature time.
16:32
It responds faster than most people expect.
16:36
You'd be surprised when policies go into place.
16:38
Getting them in there sometimes is tough,
16:40
but once they're in place and they're enforced properly,
16:42
they work. Like look at the Great Lakes.
16:45
It was home to over 150 non-native species,
16:49
invasive species, Once a bit more often than any other freshwater system on Earth,
16:53
and is probably one of the biggest freshwater systems on Earth.
16:56
And now it's holding the door shut,
16:57
like with ships flushing their their tanks at at sea and boaters cleaning their
17:01
hulls at the launch. pollution can breed,
17:04
sure. And it can spread and it can hide.
17:06
And we've shown again and again that we can stop it.
17:09
All we have to do is put the policies in place and enforce those policies once
17:12
they're in. Mistakes happen. Sometimes they're bigger than others.
17:15
Totally understand. as the world becomes more globalist and we're we're
17:19
all mixing in, we have to ensure that there are
17:23
Policies and regulations in place and laws enforced to ensure that everything
17:27
is not being changed. one study that I was a part of,
17:30
it was really just a more of a exercise,
17:33
I guess, is we looked at how similar the fish populations got within
17:37
the Great Lakes over years. So we had data all the way back from the 1800s,
17:41
and we looked at it presently at the time was like mid 2016 and we or mid 2012.
17:46
And I I looked at it.
17:48
Like as the years went by, the decades went by,
17:51
we started to see a like it it was less diverse and more similar because
17:56
of the lock system, because of all the travel,
17:59
these fish are able to get into different places and there are certain fish that
18:03
will dominate others. And it changes the diversity,
18:06
it changes the biodiversity that we see,
18:08
and it can switch up the system.
18:10
Having other species that come in from other places around the world that
18:14
can take advantage of these like Asian carps and so forth,
18:17
that becomes a dangerous situation because it can change habitat.
18:20
Anything that changes habitat can really have an effect on the populations that
18:24
are here, whether they're fish or invertebrate populations.
18:26
And this happens not only in in the Great Lakes or in lake systems
18:29
and freshwater systems. This is happening in the oceans.
18:31
We just saw that with the lionfish.
18:33
It's great to see them in the southeast Pacific,
18:35
but not in the Caribbean, not in the Atlantic.
18:38
which we gotta make sure that we keep them where they belong and to make sure that
18:41
the systems where they are are pretty safe.
18:43
And this happens in ecology all the time.
18:46
~ and it and it changes how a system will run with underwater.
18:51
And I think we have to be very careful on how that diversity gets affected
18:55
in that way. But that's it for today's episode.
18:57
I would love to hear your thoughts.
18:58
If you're listening to this on Spotify,
19:00
I love Spotify because it has a comment section.
19:02
I normally listen on Apple, but I'd love Spotify for the comment section.
19:05
So let me know what you think about this episode in Invasive Species.
19:08
If you have a story to share, love to hear that.
19:10
Also, you can just hit me up on my socials.
19:13
The links are in the show notes to see to have that conversation.
19:16
Cause this is the beginning of that conversation.
19:17
Unfortunately, podcasting, I can't get responses back quickly,
19:20
but I would love to hear what you think.
19:22
because ideas are what leads to solutions.
19:25
And we really need a lot of solutions.
19:27
So thank you so much for joining us.
19:28
Thanks for being a part of this community I can't wait to talk to you next time.
19:31
This has been another episode of the How to Protect the Ocean Podcast.
19:34
I'm your host, Angela. Have a great day.
19:35
We'll talk to you next time and happy conservation.