The Tiny Fish Holding the Ocean Together Are at Risk

0:00 As the ocean warms, some of the species holding marine ecosystems together may be tiny fish most people never think about. This is the How to Protect the Ocean Podcast, your weekday ocean news update. If you care about staying informed on the ocean every weekday, hit that follow button right now so you don't miss tomorrow's story. Today, we're talking about climate change, ecosystem resilience, and why forage fish may become one of the most important conservation stories of the next decade. Because climate change is not just affecting polar bears and coral reefs. It's changing entire food webs. And forage fish are right at the middle of that shift. So why are these tiny fish becoming even more important in a warming ocean?

0:41 That's really the question to ask, isn't it? And what happens when climate stress collides with already pressured ecosystems? Let's talk about it. Forage fish are highly sensitive to environmental conditions, and that includes ocean temperature, plankton availability, oxygen levels, ocean currents, a lot of different things. Even small environmental shifts can affect where these fish live, how successfully they reproduce, and whether predators can find them. Marine heatwaves are a major example. During extreme warming events, plankton production can change dramatically. Because forage fish feed heavily on plankton, these populations can also shift or decline. That creates a chain reaction.

1:23 And if forage fish move farther offshore, predators may struggle to keep up. If populations crash temporarily, predators may suddenly lose access to a major food source. And scientists are already seeing signs of this actually happening. In some regions, seabird colonies have experienced breeding failures linked to forage fish shortages. Adult birds simply cannot find enough food for their chicks. Same with whale feeding grounds are also shifting as prey distributions change. Some other things that are happening, you know, you look to see salmon populations in certain areas are dealing with increasingly unstable food conditions during their life stages. So we're seeing that shift in foods in terms of the whole parameters of shifting baselines and everything that's happening.

2:06 But then there's also another thing that we rarely talk about, and that's upwellings. Upwellings can shift in where they are going to be, 'cause an upwelling is essentially this current that comes from the deep oceans, brings nutrients to the top, phytoplankton, zooplankton, and that will attract forage fish. Those forage fish will come in, and then, of course, their predators are gonna come in, whales, sea turtles, tuna, salmon, cod. Depending on where they are around the world, you get a lot of fish that are coming in. Seabirds, sharks, all these different prey and predator interactions will happen during that time. And that's on different multiple stages. Now, if those upwelling shift, and they shift outside of migration routes, or they shift outside of regular areas that they're normally gonna be, you're gonna see a shift in where those forage fish are gonna go.

2:48 And you're gonna see a shift in where those predators are gonna go, but there's gonna be some loss of life because of that chaos that happens as shifting baselines happen. And that's something that you don't want to see. So what makes forage fish so important is that they connect the lower ocean productivity to larger predators. They stabilize the ecosystems, just like I talk about how diversity stabilizes ecosystems, which means when ecosystems become stressed, forage fish become even more critical. This matters because climate resilience is not just about protecting species individually. It is about protecting ecosystem function. Healthy ecosystems need strong food webs. They need enough species to absorb environmental stress.

3:28 Think about it like financial savings. I know. Why are we getting into finance? But just trust me on this. If an ecosystem has abundant forage fish populations, predators have a buffer during difficult environmental periods. But if forage fish populations are already heavily reduced from industrial fishing or habitat stress, ecosystems become more fragile. There's less margin for error. So that means climate impacts can hit harder and faster. And this is especially important because climate change is creating more unpredictability in the ocean. Species are shifting northward because they can go in warmer waters. Seasonal timing is changing. Migration patterns are becoming less reliable, which we're seeing with the North Atlantic right whale when they start to go up to the Gulf of St. Lawrence and where they saw more death because of human impacts.

4:14 And predators are increasingly competing for food resources that may no longer be consistently available. Now, one concept scientists talk about is timing mismatches. As an example, predators arrive at traditional feeding grounds expecting large schools of forage fish, but warming conditions may have shifted the timing or the location of those forage fish. That means predators show up at the wrong place at the wrong time. And in nature, timing matters, and it can be a heavy consequence if you show up at the wrong place at the wrong time. And before we continue on what happens next, I wanna just talk to you a little bit about how this is all involved in communication. Now, as I'm communicating this to you right now about forage fish, about the fish that nobody talks about or nobody really understands, and how important it is to stabilize an ecosystem, communication is really important, not just for your organization, not just for you as a science communicator.

5:04 It's important for everybody to understand what is happening in the ocean. And we can't just communicate through peer-reviewed papers because they are behind those walls, those science journal walls that cost forty dollars a paper just to get. And not everybody knows a professor or the academic author who actually puts this together. And so what we really need here is we need people to help us out with science communication. And I work for Pisces Oceans. I'm the ocean communications manager, and we help organizations, academic projects and for-profit companies to get their message out and amplify that message. We look at the strategy of who they're messaging, their target audience, what they're trying to say, why it matters. We have scientists, we have ocean communicators, we have project managers.

5:47 The whole slew of people in one consulting firm, and we wanna help you. So if you want more information and you wanna find out how you can get help from us, go to piscesoceans.ca. That's piscesoceans.ca. I'll put the link in the show notes and fill out the little tool that I link to so that you can find out where you need help the most. All right, let's get back to our show. Let's talk about what happens next. This is where more scientists and conservation groups are arguing that protecting forage fish should be part of a climate change adaptation policy, not just fisheries policy. There's a major shift in this thinking because for years, climate adaptation discussions focused heavily on infrastructure, emissions, and coastal protection.

6:29 Those issues absolutely matter. But ecosystems also need biological resistance. And that often starts at the bottom of the food web. Some fisheries managers are already incorporating climate data into stock assessments. Others are exploring more precautionary catch limits during warming periods. Researchers are also using ecosystem models to better understand how climate stress affects predator-prey relationships. But there's still uncertainty in everything that goes on. Climate systems are changing quickly, and forage fish populations can fluctuate naturally even without human pressure. That makes management extremely difficult. Still, one thing is becoming increasingly clear.

7:11 If ecosystems are going to survive accelerating climate stress, they need strong foundations, and forage fish are part of that foundation. Climate change is testing the resilience of ocean ecosystems, and the species helping hold those systems together may be the smallest fish in the sea, the forage fish. So it's important to get to know more about these forage fish. And if you've been listening for the last three episodes, this is our fourth episode that we do on forage fish, you're gonna wanna hear the next episode where we talk to Jack Daly from Oceana Canada, where they just released a report on the state of forage fish in Canada. I'll be honest, it's not that great, and you're gonna wanna hear why, but the report is really laid out well. It's got a number of different stories from a number of different rights and stakeholders, and I think it's really important to listen to that conversation that I had with Jack Daly.

7:57 So if you want to know more about what's the conversation is gonna be, I want you to follow this podcast, How to Protect the Ocean podcast, so you get tomorrow's episode and your weekly ocean news update from Monday to Friday, where we do an interview on Friday, and we set you up to success for that interview on Friday by going Monday to Thursday solo episodes like I'm doing right now to explain and prepare you for what we're gonna be talking about so you have a better understanding of what's gonna happen on Friday. I wanna thank you so much for joining me on today's episode of the How to Protect the Ocean podcast. I'm your host, Andrew Lewin. Have a great day. We'll talk to you tomorrow, and happy conservation.