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HAMANN:

Welcome to another episode of the Econews Report. I'm your host this week, Alicia Hamann, and today we're going to talk about how we monitor and count fish in general, with a specific look at recent population estimates in the Eel River. Joining me today are Dave Kajtaniak, Environmental Scientist for the California Department of Fish and Wildlife. Hey, Dave. Hello. And Samantha Kannry, Fish Ecologist with TRIB Research. Hi, Sam.

So I want to start off just by orienting folks to the historical abundance of fish in the Eel River so listeners have something to compare to the figures you hear today. Anyone living in the Pacific Northwest has undoubtedly heard references to the days when you could walk across their backs, hearkening back to days when salmon returns were so plentiful that they literally filled the banks of the rivers. In the early 1900s there were a number of commercial canneries developed in the Eel River and those provide data about exactly how many fish were being harvested and using, you know, a little bit of extrapolation we can safely say that there were upwards of a million fish and that's a combination of coho and chinook salmon as well as steelhead coming into the Eel every year. Obviously that is nowhere near where we are today but we're going to talk a little bit about what the recovery targets are and those are those are numbers that are developed by state and federal agencies aiming toward recovery for the fish and what we're seeing today and what kinds of efforts are being made to improve populations.

So let's start off by ... Dave, do you want to tell me a little bit about the history of the department and how you all have counted and monitored fish and what kinds of goals you have for recovery?

KAJTANIAK:

Sure, yeah. So as far as how CDFW has been counting the fish, like you mentioned, the cannaries at the very beginning kind of provided early fish numbers. But then after that, there was the Benbow Dam on the South Fork Eel River, and that dam was there and basically operating as almost like a fish counting station from the late 1930s to the early 1970s. And that really provided like a solid, accurate counts, because they were basically counting every fish that was passing the Benbow Dam there for those like 50 years. And so in addition to the Benbow Dam, we've also been doing, has been doing, spawner surveys for many years, probably consistently in the South Fork Eel River since about 2010, in which teams have too been walking in streams and counting the fish and their redds.

And then there is also citizen scientists have been performing snorkel dives in the lower river. Those were doing also around since 2010, but more recently, these folks are using drones to help like get aerial images of the fish in the lower river and counting them. And those counts have been matching up well with what we've seen on the sonar camera.

And then there is also the Van Arsdale Fish Station located in the very upper river, in which they count basically adult Chinook salmon, as well as their jacks and steelhead that are passing that fish station. But granted, that's in the very upper portion of the river, but that data set also goes back since the dams were there, which I believe since the 1930s. But that really only captures about 10% of the population. And so it doesn't accurately reflect the entire population. And that is just capturing Chinook and steelhead generally that are going up there.

So more recently, knowing that we don't have like these accurate counts out there, we started using sonar cameras in the Main Stem Eel River, South Fork Eel River, that one's operated by Cal Trout, California Trout. And then more recently, we started a camera in the Van Duzen River as well, so that these can help count the number of fish coming into the river and going upstream.

HAMANN:

So when people are doing the spawner surveys that you mentioned, are they swimming through the river, are they hiking along the banks and they're just kind of looking at fish and counting them? How do they know that they haven't counted a fish twice? Like, are there methods that they use?

KAJTANIAK:

Sure. They developed a fairly strict protocol and most of the time it's teams of two walking up the stream in these predetermined reaches and there's a whole sample frame that's developed. And generally, like for the South Fork Eel River, for example, there's about 38 reaches that we cover and you're able to, based on that sample frame, extrapolate into an overall population. But going back to your original question, it's generally teams of two walking up a stream looking for fish such as Chinook, steelhead, and coho, creating these potential redds, counting the redds, marking the redds, and so that they're not recounted. And same with if there's carcasses, there's a way to mark the carcasses so they're not recounted and by chance recapture them, so to speak. So it's very systematic these days in which the redds are counted. Cool. Some are done by, most of the time it's just done by walking up the stream, but some of the larger reaches are actually done also by boats in which you're floating down the river and counting these redds. Sounds like fun. It is. It is fun surveys. I mean, it's pretty exciting to be able to see live fish creating these redds.

HAMANN:

So the cameras, are those in place seasonally?

KAJTANIAK:

Yes, and so the cameras are put in basically right before the fall rains begin, and they're in the river, hopefully through the entire time that the adult fish are moving upstream. So for Chinook salmon, we put these cameras in generally before the fall rains, which can be either October or November. And then we're also trying to capture the steelhead runs in the Maine Steel Mill River. And so the steelhead run generally goes from mid-December until early April. So if the flows are correct and everything, we have the cameras operating 24-7 in the rivers during that time.

HAMANN:

Samantha, I know that you have done a lot of research into summer steelhead, and I know their populations are a lot smaller, but with the timing of when those cameras are in place, would they be capturing any of the summer steelhead migration?

KANNRY:

Yeah, I think they could capture a bit of the migration, the upstream migration, probably not the extent of it, but also depending on the year, like when they're able, there can be certain times when there's really high flows in there or certain years when the fish just come in a little later because there's a bit of variation between late April through early June.

HAMANN:

And I guess we should back up a little bit just to introduce people who aren't aware of the amazing summer steelhead. Do you want to talk a little bit about what makes these fish

KANNRY:

special? Yeah. So in the Eel, we have two runs of steelhead, winter run and summer run. And winter run enter freshwater, as Dave was saying, in like mid-December through April, primarily mid-December through March and kind of petering out after that. And they enter freshwater sexually mature, swim up to their spawning grounds and spawn, and then mostly return to the ocean. Some of them don't make it back out to the ocean. Summer steelhead, differently, enter freshwater between the end of April to early June, and they enter freshwater sexually immature. They swim higher up in the watershed than the winter steelhead, often as high as they can go to find like deep, cold pools and wait out the hot summer months. And then with the return of the rains in the fall and early winter, swim up to their spawning grounds and then spawn and return to the ocean. So they have a much longer freshwater phase than the winter run steelhead do.

KAJTANIAK:

Alicia, you had asked about having the cameras to potentially try and see these summer steelhead when they're moving up. And there was one year we kept the camera in. Normally, like I said, we take it out in early April. But one year we attempted to capture the summer steelhead run by keeping the camera in through about mid-June. And while we definitely saw steelhead passing the camera, there was also a lot of Sacramento pike minnow passing the camera. And so it really created a lot of noise and hard to distinguish the steelhead between some of these larger Sacramento pike minnow that were also basically migrating upstream or moving downstream, just moving all around. And so we were unable to do what we felt like was an accurate population estimate for the summer steelhead via using the sonar cameras.

HAMANN:

Oh, I bet. Well, and I know we've talked about this on this program before, but remind us again, once you get the camera footage, is there someone like a real human who's sitting there watching all of it? Or has the department moved on to using AI programs to determine like, what's the difference between different species

KANNRY:

KAJTANIAK:

So we are, someone is back at the office and reviewing all this data footage. It takes a long time to review this data. So we use a subset of the data, basically 20 minutes on the hour, every hour. And so we're looking at basically 24, 20 minute samples each day. But currently, while the AI technology is being developed, we have been working with Caltech to try and use their software to help count these fish. It's not quite there yet, but we hope to get there. Their funding has always been a little bit sporadic, but more just recently, they received more funding and they're also bringing on MIT to help with this AI technology. So I think it's coming in the near future that we'll be able to use this software to count the fish. Hopefully it'll be able to eventually tell the species, but there will still always be a human element, basically checking the data as well as performing quality control of it.

KANNRY:

The summer steelhead are somewhat unique in terms of the Eel river fish in that we do have a pretty good way of counting them because they're just in these clear pools and particular habitats all summer long and so we feel pretty good that we are getting a fairly accurate estimate of the numbers in there and so using the additional camera imagery isn't quite as necessary for the summer steelhead as it is for the other native fish.

HAMANN:

Are there teams of people that you work with who regularly go out and count the summer steelhead, or is that just like a couple years when you have funding for such?

KANNRY:

programs? We've been doing it every year on the middle fork of the Eel. It's been done every year for since the mid-1970s, and it's been led by various district biologists over the time. And then I've been helping with those surveys since about 2010. And then on the Van Dusen, we started an annual dive survey in 2011 and have done it every year since then. And prior to that, there were five years where the entirety of the summer holding habitat was surveyed, but it hadn't been done quite as regularly. Yeah, it's a little different than a lot of the other surveys where it's just we go out because there are 20 to 25 mile stretches of river that we're going through in the summertime. We just go out as one team of somewhere between two and seven individuals, depending on the year and the area, and just count all the fish in a three to five day period. And that's kind of the extent of the summer steelhead population estimate.

HAMANN:

You mentioned the that the entirety of the summer holding range has been reviewed just a couple of years. What what is that range? Are they up in the North Fork? Are they up real high in the main stem? Have you ever found any in the South?

KANNRY:

Yeah, we haven't found any in the South Fork. We haven't done extensive dive surveys there, but we have done some genetic research that leads us to believe that there aren't summer run currently in the South Fork. There is some pike minnow and summer steelhead dives that go on the entirety of the main stem of the North Fork, and they've seen a few scattered summer individuals, somewhere between one and I think last year the highest number they saw was 17. And then on the Middle Fork, their habitat is from just a few miles upstream of the Black Butte Confluence until a little, well, it switches around depending on how the barriers have shifted, but it has usually been up until right around the North Fork of the Middle Fork. And then on the Van Dusen, they're from a few miles upstream of Bridgeville until close to Dinsmore. Historically, we believe that they were in the upper main stem above Lake Pillsbury, according to anecdotal reports and some genetic research that we did, but there aren't any anonymous individuals up there.

HAMANN:

Frequent listeners to the Econews report have probably heard me gush about the exciting potential for reviving those populations behind Scott Dam, so yay dam removal, we won't get into that today because I think folks have probably heard enough about that, but just really, really exciting potential for the offspring of those resident trout up there.

KANNRY:

Definitely.

HAMANN:

So Samantha, you were starting to get into the numbers of how many summer steelhead we see. Dave, do you have figures from this recent year for Chinook or Coho or steelhead that you've been

KANNRY:

share with us.

KAJTANIAK:

Sure. We just recently completed our analysis of the Chinook Salmon run. And so for the Mainstem Eel River, our camera is located basically four miles upstream of where the South Fork and the Mainstem come in. And so this is numbers for just the Mainstem above the South Fork. There's basically a little over 8,000 fish. This is both Jackson adults, 8,167 is our final number. In the Van Dusen, we had almost 1,900 Chinook Salmon. That's also Jackson adults. I've heard from California Trout with their camera on the South Fork, and they estimate over 5,000, potentially even over 6,000 Chinook. And so collectively thinking that there's around 16,000 Chinook Salmon that came into the Eel River this year, potentially, give or take a couple thousand there, which has been the highest number. Probably, we started operating these cameras in the fall of 2018. Last year on the Mainstem, there was also around 8,000 fish, but it has been trending upward, which is definitely good to see.

HAMANN:

Yeah, that's awesome. Do folks have any leading theories about what's, what's causing this positive trend?

KAJTANIAK:

question. I mean, there's a lot of factors. This year, I think what could have played into it was the closure of the ocean fishery. Granted, that closure affects definitely more of the Klamath fish and Smith River, but I think that there's certainly a good number of fish from the Eel that are being caught. This year, I think, was helped by that fishery closure, which unfortunately means the overall population has been down. So the Eel's kind of been different in the way that we've had better numbers the last two years than the previous four years of the project.

HAMANN:

We're talking about how we monitor and count fish in general with a specific look at recent population estimates in the Eel River. And does it make sense to look back a couple of years to the conditions that these fish were juveniles in to possibly make some guesses about if the conditions were really good three years ago when they were babies coming out of the river? Does that bear any impact on population sizes?

KAJTANIAK:

That does. It certainly depends on the winters and how successful the redds are and also the stream conditions in the summer. I mean, Chinook salmon don't over-summer in the rivers. Rather, they move down shortly after hatching from their eggs and basically head down the river in the spring. But better summer conditions certainly affect steelhead and coho. Well, last year was obviously a really wet year and certainly benefited, I think, the fish in the river. Going back three years to when we're now seeing these better runs, I guess it can be a little bit surprising because there was some drought years in there. And so the higher return was maybe a little bit unexpected for the Eel. So I haven't placed my finger on what's been going on, I guess, in the past couple of years. I mean, there has been a lot of restoration in the South Fork particular, as well as throughout the watershed. And that certainly can only help as far as the success of the redds, fish spending time in the rivers and being able to come back. Definitely.

HAMANN:

a lot of variables, especially when the fish are in both fresh water and salt water. So about 16,000, give or take, Chinook, and those are the most plentiful salmonid species. You have figures for coho and steelhead as well?

KAJTANIAK:

I don't have figures for Coho in the sense that the main stem Eel has a very small run of Coho left. They've been almost extirpated from the system. There's really maybe just a couple hundred that go and utilize mostly Outlet Creek and the Upper Basin, still below the dams. But as far as Steelhead, unfortunately the last two years with all this rain, we have not been able to keep the camera in much during the Steelhead season. Like basically the high flows, these cameras are situated on a river bar and you have really high flows that almost take up the whole river bar, you're not able to keep the camera in. But last year's Steelhead numbers were really poor. We basically had the camera in during the month of February, which should be like one of the prime times that this Steelhead are running and we only counted 400 fish, which was a horrible number. This year we had it in just for 14 days at the end of December and into January, at least had like a thousand fish. So and I've heard from Caltrout's South Fork camera that they've been seeing better numbers of Steelhead this year than last year.

HAMANN:

So there's obviously other ways to count the fish and find them and I think when when you have a more human approach you can discern a lot of things about behavior and and really kind of get to know the fish better. Samantha, I know that your work with TRIB Research, you've developed a technique for following the tributaries. Do you want to talk a little bit about minking and the fun adventures you've get up to?

KANNRY:

Yeah. So yeah, the term minking came from our good friend at CDFW, Seth Ricker. The idea is basically that you're just moving down the river as a mink would, swimming through pools and sliding over rocks and climbing over boulders when need be and just getting around whatever way that you can. And I mean, it's basically what we've been doing for the summer steelhead dives and what CDFW has been doing for a long time, which just has a new official term for it. And in addition, yeah, about in 2017, I started doing some genetic research on steelhead in the Eel and have since, starting in 2020, moved into other basins north of the Eel, as well as the North Fork Eel and the Matolle, and then all the way north up to the Rogue River, primarily in rivers where summer steelhead are. And we have over time refined our methods to find the best way to answer the questions we're trying to look at, which is where are summer steelhead, where are winter steelhead, and then in the Klamath and Rogue, where are another run of fall steelhead, as well as how are the anadromous and resident genotypes distributed, and then overall just questions of genetic diversity and relatedness between different populations of steelhead within a basin and between basins.

And so what we have found works the best is to go out at night with little handheld dip nets, sometimes slightly bigger dip nets, and using headlamps or more recently we've started using red lights, which seem to spook the fish even less, but they tend to be fairly calm and docile at night and a lot easier to catch. And just scooping up juvenile fish and measuring them and getting a small piece of their caudal or tail fin to then dry and extract the DNA from and begin to answer these various questions that we have. We do that in a few different ways. Sometimes it's part of our summer steelhead monitoring dives where we just, wherever we happen to be camped at night, we go to nearby tributaries or little cold spots where the juvenile fish are holding at night and catch them or we'll go just make special trips to different locations. We're trying to get distribution downstream and focus upstream and downstream of potential barriers between the two populations in Eel and then the other populations in the other rivers as well as a good geographic distribution throughout the entirety of these basins. So a lot of it where we end up going is just based on what places we want to go, but also places that are accessible as in not, we don't have to go through private land or there's some reasonable route we can take to get there or it works with other places we need to go so we can kind of group different sites together.

HAMANN:

So are fish diurnal, are they sleeping at night? And if so, are they like a sleep with one eye open kind of species or what's that like?

KANNRY:

Yeah, I wouldn't I don't think it's sleeping is the way that we think of sleeping. They're just a lot less spooked than they are during the day. They can see very well and they're really aware of their surroundings. And so anything coming up upon them, such as a large human, they just shoot off into whatever little crack or crevice or pile of algae or debris they can find. But at night, they're just not able to see very well. And so they're not aware of your presence. We have found that as the water gets colder, they seem like in the fall, they seem to become a little more spooky at night. And so that's when we started switching to using the red light because it seems like the red light, they really can't see us once we're using red lights compared to the white lights of normal headlamps.

HAMANN:

Right. Well, and they tend to prefer these colder waters, I think, because they function better. So I wonder when the water's warmer, they're just not at their peak functioning, kind of like me before a cup of coffee in the morning.

KANNRY:

Yeah, yeah, they have a much higher like metabolic requirement at warmer temperatures and so I think things are a lot of their energy is going elsewhere and they're just slower in general but yeah as the water starts to get pretty cold in the fall they they get back on their fast moving darting behaviors.

HAMANN:

Yeah. Why does it matter to, to figure out if there is genetic diversity and, and where that diversity, how it's spread out? Why? Yeah. Why does that matter for, for fish recovery?

KANNRY:

Yeah, so genetic diversity is important as just enabling fish to have higher fitness and a better likelihood of survival and better likelihood of maintaining populations into perpetuity. As you start to experience any bottleneck in most species, you end up with a lot more physiological issues that can start to pile up on each other and just reduce the viability of a population. Yeah, the diversity is kind of an additional component of what we're looking at. We're primarily looking at the distribution of these different runs, which is a type of life history diversity. So just having more life history diversity is important just for like our personal values of like we came into this place, this region, this world that had a huge amount of diversity and over time with all the ways that we've altered the landscape, we're like reducing that diversity and reducing that diversity. And in the end, that may result, that is resulting in something that is not a very pretty picture. And so it's also just that these all these different populations have, like, in my mind, just like inherent right to be there, and we should be protecting them in any ways that we can. And so understanding where they are helps enable us to protect them, as well as being able to explain more scientifically to the broader community, the local community, as well as the scientific community, why, what is going on here and giving them a reason why it might be important to help these fish.

KAJTANIAK:

I think that genetic diversity allows them to survive in various or a more wide range of conditions such as, you know, like if the greater the genetic diversity, maybe they can survive in different changes with our climate, basically. And so having that broad genetic diversity helps with that.

KANNRY:

You need lots of different strategies. Yeah, it just makes a species a lot more adaptable to all the things that may throw at it. And historically, it seems like on the Eel, there used to be a lot more diversity within Chinook and within Coho and within Steelhead. And I think this was the case in many other systems where there was just more variability within life histories. And so when there were things that occurred at a certain time or in a certain year that really harmed a portion of the population, it didn't wipe everybody out because there were all these other things going on. And then over time, they went back, filled those niches and ended up in more abundance than what we're seeing today.

KAJTANIAK:

I think that's totally right in the sense from something that we have seen is like really truncated runs of like the Chinook, mostly the Chinook and a little bit to a lesser extent of Coho in the sense that the run used to be spread out from like September through potentially even January and now we're getting such like large pulses right at the beginning of the run that's producing two thirds to 75% of the run and that's putting a lot of like eggs in one basket. If for something were to happen to those fish or the conditions in the river at that time such as extreme drought, it could really hurt that population that run that year.

HAMANN:

I think you meant a lot of eggs in one red. Yes. Yeah, I've got a fisherman friend who is constantly bragging to me about how back in the day he used to catch a steelhead every single month of the year, and he's up there in age. So I think when he says back in the day, he's not talking about a decade ago. So aside from protecting what remains as far as genetic diversity is concerned, if we create more diverse types of habitat, is that going to encourage fish with different genetic diversity to thrive and survive and, and reproduce if I guess one of the things that I think about is the genetic diversity that might exist in some of these populations of resident trout, for example, trout behind Scott Dam. But are there other ways that are there novel things people are talking about to really bring back that diversity? Because I know it, it seems like something that's once it's lost, it's lost. But I'm just wondering if those of you on the emerging front of scientific research, know anything about that.

KANNRY:

Yeah, those adaptations are something that occurred over a very long period of time. And so without some really weird techno genomic fix of like, altering genes, which I don't think is something we want to even consider as an option, like, some of it is just restoring the habitat and removing some of the pressures that we placed there. And then just knowing that it's going to take a lot of time for things to settle back in and not expecting to see changes on a human timescale of things that took like a geologic timescale to arrive.

KAJTANIAK:

I think that's right. I mean, you know, like what's special about the Eel River populations of some mountains is that there hasn't been like really a hatchery influence in a very long time. And so I think that's what can potentially help them in the long term is that there isn't this human influence on their genetic stock. They're more of a true wild fish that has been able to survive and flourish throughout obviously time memoriam.

HAMANN:

Before we wrap up here, I want to get back to the numbers. We talked a little bit about how the returns that we saw this year in the Chinook populations were quite significant. Is that anywhere reaching the recovery targets that our wildlife agencies have set?

KAJTANIAK:

Yeah, I'm glad you asked that question, because even though we've had relatively good numbers the last two years, they are still far below the numbers that we are hoping for. They're federally listed species as threatened, and the number for the main stem ale, the NOAA number for recovery target is 10,600 fish, so that's just like a bare minimum to potentially get them off, become delisted, and that would have to happen for a number of years as well. So 8,000 fish is still below that 10,000 number, and even more significantly is the steelhead number, they're also listed, and we're far below the number to delist them, which is about 22,300 I believe, so it seems like we're getting just somewhere around 5,000 steelhead returning, so that number is far below that 22,000 number that they're looking to hopefully delist them. So we still have a long way to go.

HAMANN:

go. Long way to go indeed. Samantha, if people want to learn more about the research you're doing with TRIB research, where can they go?

KANNRY:

The best thing right now would be to go to our website, which is www.cribresearch.org, and there we'll have information about the events that we put on at the farm in Bayside or other things that we're up to, and it has a bit of information about a little more write-ups of the various fieldwork that we've been doing in the past year.

HAMANN:

Great. And we'll put a link to that in the show notes as well. Well, thank you both so much and keep up the good work. Let's keep our fingers crossed that we keep seeing this positive trend of salmon returns in the

KAJTANIAK:

Well, thank you very much for having us.

KANNRY:

Cool. Thanks, Alicia.

KAJTANIAK:

It's good to talk to you today.

HAMANN:

Thanks for listening to another edition of the Econews Report. Join us at this same time and place next week for more environmental news from the North Coast.