Show Notes
Back in 1946, the Wisconsin Conservation Commission had the idea to set aside an area made up of five lakes in Vilas County for fisheries research.
Using special free permits and mandatory reports from all anglers fishing the lakes, they’ve gained a lot of knowledge and tested the impact of various fishing regulations on those fishing populations.
We’re celebrating the 75th anniversary of this groundbreaking research area. To learn more, we spoke with the facility’s lead reasearcher, Greg Sass. Listen in as he talks about the way the data is used, how it has evolved over the years and what the hopes to see over its next 25 years.
Learn more about research at the Wisconsin DNR:
https://dnr.wisconsin.gov/topic/Research--------------------------------------
TRANSCRIPT
SARAH HOYE: [
00:00:00] From the Wisconsin DNR, this is Wild Wisconsin. Bringing you inside voices on Wisconsin's outdoors.
KATIE GRANT: [
00:00:16] Welcome back to another episode of Wild Wisconsin "Off the Record". I'm your host, Katie Grant. After World War II, fishing and resort-based tourism was beginning to boom in northern Wisconsin, specifically near Boulder Junction. At the same time, the Wisconsin Conservation Commission, which is now known as the DNR recognized a need to better understand the fish population in the area. In 1946, they established what was then known as the Five Lakes Research Project across well, five lakes in the area. It utilized special licenses and reports from all anglers on these lakes to gain data and test the impact of various regulations and stocking practices.
Flash forward to 2021. And we are celebrating the 75th anniversary of this groundbreaking research area. Over the years over 243,000 anglers have fished the shores of just Escanaba Lake accounting for over 1 million hours of angling effort. It's now known as the Northern Highland Fisheries Research Area.
Greg Sass has been the lead researcher there for half a decade. Sit back and listen in as we talk with him about how the research here is used, how it's evolved over the years and what he hopes to see over its next 25 years. All right. Well, welcome to the show, Greg. We are very excited to talk about the Northern Highland Fishery Area and its upcoming anniversary.
But first, why don't you tell us a little bit about who you are and what it is?
GREG SASS: [
00:01:53] Well, thanks so much for having me, Katie. It's exciting to talk about, uh, the 75th anniversary of the Northern Highland Fishery Research Area coming up. Uh, my name is Greg Sass and I'm Fisheries Research Team Leader in Wisconsin, DNR Office of Applied Science.
And my role within the agency is to lead our group of fisheries, research, scientists, biologists, and technicians to address high-priority fisheries research needs for our fisheries management program, um, and other program partners. So, um, I helped to facilitate that program. Um, I oversee and direct the Northern Highland Fishery Research Area Program. And then we work extensively, uh, with university partners and our stakeholders and tribal partners, um, as well to conduct research, to benefit the fisheries of Wisconsin and beyond.
KATIE GRANT: [
00:02:40] We've both mentioned the Northern Highland Fishery Area. Can you tell us a little bit about what it is and why it was established?
GREG SASS: [
00:02:48] Absolutely. The Northern Highland Fishery Research Area, um, was established in 1946 by the Wisconsin Conservation Commission at the time, which is now of course our Wisconsin Department of Natural Resources. Um, and at that time in northern Wisconsin, um, the tourist-based in, in fishing resort-based economy was just starting to pick up.
And we didn't have a tremendous amount of information about our fisheries in this part of the state. And in listening to anglers and stakeholders, our anglers were concerned about stunting and fish populations, and stunting is basically, um, slow growth and in low size structure or a lot of small fish in a population.
And in response to that, the Wisconsin Conservation Commission, uh, set aside five lakes in Vilas County, near Boulder, Boulder Junction to use as experimental fisheries research lakes. And at that time to address the question of stunting and fish populations, the default regulation on all five lakes was that there would be no size limit, no bag limit, and no closed season on any species unless specified for research purposes. And so, um, the, the lakes were set aside initially to, uh, look at a test. We're gonna allow, um, as much harvest of any size and. Um, any fish species, uh, without any closed seasons to see how those fish populations responded.
Um, in addition to that, the five lakes were chosen to be representative of the lakes in the area. So, um, Vilas County has about 1300 lakes and they're, they're very diverse from clear to, uh, very tannic, meaning that the waters slightly stained brown, um, to deep, to small, to large. And so the five lakes that were selected kind of represent that gradient with Escanaba Lake, uh, being a drainage lake with fish species, diversity Pallette Nebish lake, being what we call our classic kettle lakes, where an ice block was left in the landscape from a glacier. So they're deeper and they're clear, um, and relatively unproductive. And then we have two sphagnum bog lakes, which are kind of more of our wetland lee lakes with darker water color in a Mystery Lake and Spruce Lake.
KATIE GRANT: [
00:04:51] Can you just kind of clarify a little bit because I don't understand necessarily the different kinds of lakes. You mentioned that the kettle lake is, is left from the glacier. Can you talk a little bit more about the other two?
GREG SASS: [
00:05:02] So when I talk about Escanaba Lake being a drainage lake, it means that it has an inflow and outflow.
And so, uh, the inflow to Escanaba Lake comes from Spruce and Mystery Lake into the lake. And then the lake flows out to Lost Canoe Lake. And so that's what we mean with drainage lakes, uh, for Pallette Nebish when I say it was an ice block left in the landscape. These are lakes that are, um, their lake levels are dominated by precipitations and we have high levels of precipitation over time.
the lake levels are going to be higher. Um, when we have a drought, like we did in the early 2000s up here, those lake levels are going to be lower because the water table is lower for precipitation. And with our sphagnum bog lakes, these are lakes that are surrounded by lowland areas, uh, with vegetation like spruce, uh, leather leaf, uh, wild cranberry.
They're more of our wetlands sort of lakes. And with that wetland influence, uh, they tend to have, uh, a tea or a coffee-stained color water. And that's what I mean, when I say tannic.
KATIE GRANT: [
00:05:57] The main purpose of the fishery area is really research. Right? Can you tell us a little bit about some of the projects that have happened there over the years?
GREG SASS: [
00:06:06] Absolutely. Like I mentioned, early on the initial regulations were set up to, um, see about stunting and fish populations and how, um, high exploitation or a lack of regulation would influence that. But over time, there's been a number of different research projects that have been conducted on the lakes that have had, um, you know, pretty fair significance and importance.
I would say, you know, first of all, um, we might not realize that at that time was that by, um, and I should've mentioned this previously, that we have a compulsory Creel survey on all five of these research lakes. And so any angle that wishes to fish, one of the five lakes has to check in and fill out a free permit at the Escanaba Lake Research Station prior to fishing one of the lakes, um, they go out fishing and when they get done, they're then required to check back out at the station and report certain things about their catch.
Um, and so this data set has been incredibly important to us. Um, and the fact that allows us to calculate angler effort, harvest rates, catch rates. And then when, when I was getting to initially, um, in responding to the research, it also allows us to calculate an exploitation rate or how much of that fish population was removed in a given year.
And so those exploitation rate research has been really important for, uh, managing fisheries in Wisconsin and beyond because it's allowed us to, um, address what might be a sustainable exploitation rate for a population. Uh, so for example, for some of our walleye regulations right now, um, Escanaba Lake showed that an average exploitation rate over time of 35% of the adult population was sustainable. And so that's the same exploitation, uh, limit reference point we use for, um, many of the lakes in northern Wisconsin right now. Um, same thing in our joint tribal, um, and angling [unintelligible] fishery, where that limit reference point exploitation rate is 27%.
Um, on top of that, um, some of the other key research has been conducted we've, um, or I should say my predecessors have developed, um, indices to, um, go from a relative abundance estimate of walleye recruitment up to lake-wide densities. We've tested a number of different regulations on the lakes before they might be, um, implemented more broadly throughout the state.
Uh, for example, minimum length limits on Northern pike, which occurred on Escanaba Lake. Uh, we've had various small mouth bass regulations on Nebish and on Pallette lakes. Um, that often ended up in our fisheries management toolboxes for certain purposes. And then, um, more recently, you know, a number of different studies where Escanaba Lake has served as a reference lake, um, to other whole lake studies that we've done.
Um, And so those are just some of the examples of the many ways that we've used the lakes for research. And I would add on top of that, that, um, many undergraduate and graduate students have also used the lake for, um, their thesis and dissertation research, uh, covering a wide range of topics ranging from things like, um, genetic influences in small mouth bass.
Nesting and reproduction to influences of regulations, um, and for many purposes. And so, uh, we also have a pretty strong presence, um, educationally with graduate students using the lakes to address research questions as well.
KATIE GRANT: [
00:09:19] Yeah. Lots of great information coming into you guys. So you mentioned those, uh, Angler Creel surveys where those who go out, fishing in these lakes have to come back and kind of report back. What sort of information do you get from anglers on the lake?
GREG SASS: [
00:09:35] When an angler comes... like I said, they have to check in or required to check in at the Escanaba Lake check station. It's right at the Escanaba Lake boat launch. Um, there.,Uh, my team of Creel clerks and research scientists, biologists, technicians there, uh, we'll check the anglers in. And when they come in, uh, they have to fill out their name and their address, um, and a bit of demographic information about gender and an age range and what lake they're going to be fishing. Um, so we give them the top copy of the permit, which says that they checked in as required and they take that with them while fishing and when they get done fishing, um, the things that we collect when they report out are things like the amount of hours they fished on the lake.
Uh, what kind of bait they might've been using. Live artificial or a combination of both. We ask them what kind of methods they were using. Were they fishing from the boat? Shore? Um, were they ice fishing? And, uh, or were they just casting or trolling or motor trolling, those sorts of questions. And then we get into some other important information.
Um, one is harvest information. So any fish that are harvested by the anglers, we get the length, the weight, uh, the sex of that fish. And then we also pull an aging structure from all of them. We also look for marks on the fish, and this might be a thing like a fin clip or a Floy tag or a PIT tag, uh, because this allows us to calculate an exploitation rate based on our other surveys and through an equation in doing so.
And I will add the most recently, one of the interesting things that we've observed at the Northern Highland Research Area is the prevalence of catch and release, um, over time. And that more anglers are catching and releasing fish than they used to. And so this is an area where, for most species, you can harvest as many as you want.
Um, but despite that we've seen major changes in the catch and release ethic, particularly towards large mouth bass, small mouth bass, and muskie over time. And so in the initial design of the Creel survey, the information collected, we will lose all that information. Cause we were only getting information from harvested fishes.
Now we also asked anglers to tally, uh, within size range by species, um, fish that they might've caught and released. And so we implemented this about five years ago and it's been a very important data set for us to capture not only what's coming through the Creel survey that is harvested, but also fish that are caught and released. And so it gives us information about the size structure of the population and additional catch rate.
KATIE GRANT: [
00:11:51] You mentioned that, you know, this research, uh, the data we have available has been used by graduate and undergraduate students. You know, it's, it's informed things that we do here at the DNR in Wisconsin, but also beyond.
Can you talk a little bit about why the data set is so important from a research perspective, both here for Wisconsin and, uh, outside of Wisconsin as well?
GREG SASS: [
00:12:14] Great question. I think it really lies in the strength of being such a long-time series. And so we have 75 years of continuous data, uh, from the Northern Highland Fishery Research Area.
Or we will on June 20th here, um, this month, uh that's when the first permit was issued in 1946. And I'll quote, Secretary Cole here on a visit from a couple of years ago, he came up to visit the field station and said 75 years is a long time for anything. And so we agree, but in the fisheries world, having a time series of data from these five lakes for 75 years is pretty much unprecedented.
Um, to my knowledge, there's only one other small field station in south central Illinois that has a data set this long and that's from Ridge lake. Um, so we're really unique. Here in Wisconsin, anywhere around the world to have this amount of continuous data to use. And long-term data, um, obviously is difficult to acquire.
It takes a long time. It's expensive. It requires a lot of effort, but it's also incredibly important for being able to monitor fisheries and changes that may occur in those fisheries over time. And so I think that's one of the greatest strengths and why we've been able to do so much with this dataset and also, you know, contribute with others, with data requests that they might have to help them in their research.
Um, and so I think really long-term data is something that, um, most agencies or places don't have that we do, um, that really sets us apart. And it makes us data set even more important.
KATIE GRANT: [
00:13:39] We'll talk a little bit more about some of the things that you've learned from the dataset, uh, in a little bit here, but one of the things that, uh, I thought was really fascinating about, uh, what you guys are able to do and what that data is used for, um, is that it, it actually helped influence the, uh, Ceded Territory of Wisconsin Walleye Management Plan.
What role did the research area play in that Ceded Territory of Wisconsin Walleye Management Plan and kind of how, how has that information been used specifically for that?
GREG SASS: [
00:14:15] That's another great question and the Northern Highland Fishery Research Area, particularly Escanaba Lake played a, uh, a very significant role in the management plan that we're currently using in the ceded territory of Wisconsin, which is about a northern... the northern third of the state.
And so, um, as a little background in, in the treaties of 1837 and 1842, um, Ojibwa Native Americans ceded, uh, two large chunks of land in northern Wisconsin to the federal government, which would later become, uh, the state of Wisconsin. And in those treaties, the Ojibwe Native Americans, um, were allowed to hunt, fish and gather on off-reservation lands as a part of those.
And for a long time, those treaty rights were really not acknowledged. Uh, but in the early 1980s, uh, through the Voigt case, those treaty rights to hunt fish and gather on off-reservation lands in the ceded territory of Wisconsin were affirmed. And so, um, tribal spearfishing for walleye in the Spring, um, was back again, um, as allowed by those treaties.
And so, what it set up was the challenge of now, um, managing a joint fishery for walleye that is a travel spearfishing and recreational angling fishery. And at that time as an agency, we really only had walleyed data on some of our best wildlife populations. We didn't have a standardized monitoring program.
And so, um, establishing a management plan that would be sustainable. Um, given the joint fishery, um, was a challenge, uh, but we had Escanaba Lake, which at that time had 40 years or so of....oh, yeah, 40, 30, 40 years of data or so on walleye harvest from Escanaba Lake and exploitation rates during that time. And so during that time, when the walleye management plan was being developed and standardized, uh, by 1990, the average sustainable exploitation rate for walleye in Escanaba Lake was 35%.
And that's still what is used today as the limit reference point in our ceded territory of walleye fisheries. And when I say limit reference point, is it's not a target to hit 35% for every walleye population it's the maximum allowable, so to speak. And so,now we use that 35% and the management plan was set up not to achieve that or not to exceed it except in one in 40 cases.
And so most cases, the walleye management plan is set up, uh, primarily based on the Escanaba data and observations from that individual population. Is that our exploitation rates range in the oh 12 to 14% or so annually between the recreational and tribal fishery. And so that information that was collected in the long-term walleye population abundances and recruitment in Escanaba Lake was primarily the backdrop and establishing the current walleye management plan used today. Um, although as we've gained more information from Escanaba Lake and other walleye populations in northern Wisconsin, uh, we often look to that now, um, to help us make tweaks within the management plan when necessary.
KATIE GRANT: [
00:17:23] You've mentioned a couple of times that, you know, the, the fishery research area is really important for getting that data set, but it's also important for us to try out regulations and, and learn what the effects of those regulations may be. What have we learned from the current walleye regulation on Escanaba Lake?
GREG SASS: [
00:17:41] You know, starting in 1946, we had no closed season, no bag limit, or no size limit on walleyes in Escanaba Lake. And that regulation ran the same up until 2003. And my predecessor at the station, uh, before me, uh, decided that we're going to go in completely the opposite direction and essentially eliminate harvest a walleye to see how that white population responded. And so in 2003, uh, we went from no closed season, no bag limit, no size limit for walleye in Escanaba Lake to a 28 inch minimum length limit and a daily bag of one fish on Escanaba Lake. And since 2003, um, there's not been a single walleye legally harvested from the lake in the recreational fishery. Although there's been a little bit of tribal harvest in there. And what we've learned from that regulation, I think are a couple of things most importantly. Um, you know, one, uh, we saw
the abundance of adult walleyes, jump up a little bit, which would be the expected given the lack of harvest. Um, but we didn't see major growth responses, um, to that elimination of harvest. And I think that's simply because there's a lot more mouths to feed out there on the lake right now. And so fish aren't growing maybe as fast as they used to.
Uh, we also, with those growth rates going down, I've seen, um, a little bit of a delay in maturation, um, compared to what we saw, uh, before the regulation. And we've also seen low and stable recruitment and so reproduction of young fishes. And so we had much more booms and busts, uh, in recruitment of walleye when it was more heavily exploited. Under low exploitation, uh, we've kind of just seen low and stable recruitment, which is very different from what we observed previously. And we reasoned that that's likely just an unexploitation effect such as there's already a lot of mouths to feed in the lakes. And there's also a lot of competition. And so, um, we don't see a higher level of recruitment like we do, um, under exploitation. In many ways Escanaba Lake right now is, um, acting like relatively unexploited walleye fisheries and other places for example. Canadian shield lakes, we have a lot of fish in the [unintelligible] range out there. Uh, but we don't see it a lot of, uh, very large individuals, just because of the sheer number of fish in the population.
KATIE GRANT: [
00:19:50] Technically speaking, walleye could be harvested, it's just that there's that length, a minimum that needs to be met and they just haven't been growing big enough and being caught if they are, uh, to be able to be legally harvested. Right?
GREG SASS: [
00:20:03] That's correct. And so we just, we don't have a lot of large fish in the population. In fact, uh, we haven't seen her in a couple of years in our Spring surveys, but, um, the only walleye that we've had since 2003, that's exceeded 28 inches is Floy tag number [audio glitch] 2110. And it's a female that's just over 28 inches. Uh, but she's definitely an anomaly and may have passed on, um, her nest by now because we haven't seen her a couple of years in our nets. Basically what we see... yes, walleye...anglers can harvest walleyes that are greater than 28 inches. They're just not present in the population.
KATIE GRANT: [
00:20:35] So when does that kind of experimental regulation end and what is the proposed new regulation?
GREG SASS: [
00:20:42] The current regulation will end starting next summer on the second Saturday in June. And so we've learned what we think we're going to learn from this lack of exploitation and the response to the Escanaba Lake walleye population to it.
And so now, uh, we're going to go in a different direction. We've seen some natural recruitment issues on some of our walleye lakes in northern Wisconsin over time. We also have some evidence that because of those natural recruitment declines, that there could be some production over-harvest of walleyes, which basically means that, uh, we're, you know, we're continuing to fish them, but we're just not getting, um, as many fish being produced to replace them.
And so, um, we're going to test a production over harvest experiment on Escanaba Lake that new experiment and regulation will be what I'll call our ceded territory default regulation for walleye. Which will be a 15 inch minimum length limit. A 20 to 24 inch protected, no harvest slot length limit with a daily bag limit of three fish with only one fish allowed over 24 inches.
And so this is a regulation that was implemented on many ceded the territory of Wisconsin lakes several years ago. And this regulation will also allow us to test, um, sort of influences of, of that regulation. But more importantly, is that within that regulation, we'll be establishing an annual quota in pounds of walleyes that we would like to have removed from Escanaba Lake to test the production over harvest question.
So we'll do our Spring surveys. We'll annually establish that harvest quota. And then on June 15th, I'm sorry, the second Saturday in June. Um, anglers will then be allowed to, um, harvest. That walleye quota. Um, and when that quota is met for the year, then the walleye fishery will close on, on Escanaba until the following second Saturday in June.
Um, I'll also mention that, uh, we'll have a tribal component to this as long as the, uh, uh, tribal members declare the lake for Spring spearfishing. So this is another important component of the experiment, uh, that will be, um, removed from that annual harvest quota, um, to meet our goals.
KATIE GRANT: [
00:22:48] Yeah. And I think that's a really interesting, uh, you know, demonstration of the fact that these are in fact research lakes. It's not that you've learned any or you've you found anything good or bad necessarily to cause the regulation change. The regulation changes really just... These lakes are for research. You've gotten the data sets that you need to be able to, you know, infer the information that you you were looking for or prove your hypothesis. And now it's time to try something new.
GREG SASS: [
00:23:17] Exactly. And so, um, you know, these are research lakes and research lakes are somewhat hard to come by. But every regulation change or experiment that we try, or, or some sort of manipulation we try in a lake, is an experiment that we can learn important things from.
And so, uh, you know, we're excited about this next regulation change and this next experiment. Uh, we think it's gonna help us to inform walleye management, um, in Wisconsin and, and teach us some new things. And, um, that's, that's really what it's all about is using these experiments, uh, to sustain fisheries and having these uh, research lakes established to do that, um, because it allows us to make science-based decision-making.
KATIE GRANT: [
00:23:57] So, obviously the last 75 years have been really productive in terms of research. You've gotten that giant data set. What do you hope to see happen within the research area over the next 25 years?
GREG SASS: [
00:24:11] Well, first I'd say I just appreciate the agencies and uh, the sport fish restoration program from the US Fish and Wildlife service for the continual support of the agency. And 75 years is a long time for everything, uh, for anything, but it requires support and, you know, adequate funding, um, to do that. And so, um, I'd just like to acknowledge those sources there and, and thanks for the continued support.
And I hope that continues for the next 25 years and, and the next a hundred years after that, um, as we continue to maintain this dataset, um, Looking forward. Um, I think, you know, some of our main goals are one of mine for sure, is that early on in our time series, um, we didn't collect a lot of non-fisheries related data and so things like water quality or what's happening on the landscape or in the watershed.
And so, um, we've implemented some broader sampling in order to get those water quantity, quality characteristics. Look at habitat within the lakes, and then also within the watersheds and even more, um, regionally. Um, so that we can take a more holistic approach at what might be influencing our fish populations overall.
And so, um, if anything, over the next 25 years, I look forward to continuing, to not only leverage the great data set that we have with the Northern Highland Fishery Research Area. Uh, but take a more ecosystem-based approach, um, along with social economic and social-ecological approaches, um, to help us understand our fisheries now.
And how they might respond to, uh, various changes, perturbations disturbances in the future. And then how we can use that for, um, applying management actions in Wisconsin for other fisheries and beyond.
KATIE GRANT: [
00:25:49] Yeah. I think that's a really fantastic thing to note is that, you know, so much of that data set is just the fish and not that over overarching, uh, kind of ecosystem perspective. I'm excited to see what you guys are able to, to make happen there in terms of, uh, kind of further expanding that research.
GREG SASS: [
00:26:08] It's very exciting for the station right now. I mean, not only is the 75th anniversary this year, um, you know, but also mentioned just the, the network that we as a station are involved with.
There's a lot of different scientific entities in, uh, in this region and throughout the state. And again, in some of our partners across the Midwest, um, that we've been able to tap into and it just creates this large network. For example, we do a lot of collaboration with UW Madison Center for Limnology, which is just at Trout Lake, which is only a few miles from the Northern Highland Fishery Research Area.
Uh, they're linked into another long-term ecological research program, which has 40 plus years of data now. Um, so we partnered with them very frequently. Um, we work within our, with our partners within the agency, of course, we're working with the Great Lakes Indian Fish and Wildlife Commission, which has some longer-term data and outstanding biologists and scientists.
Um, the University of Notre Dame has a research center that's very near, um, to the, to the area up here, just across the border in the upper peninsula, Michigan. Um, and we're also partners, partnering with some private entities that have allowed us to do research on their lakes to help them achieve some of their management goals and address our research goals.
And so the future is very, very bright and, uh, we continue to be thankful for these partnerships and everyone that's engaging in these broader collaborations because it allows us to do things, um, that are bigger and, and very relevant for, uh, fisheries management, aquatic ecological research and just, you know, clean water across the landscape up here. Um, so it's, it's it's really amazing to be a part of.
KATIE GRANT: [
00:27:38] Is there anything else that we might not have talked about that you want us to know about the Northern Highland Fisheries Research Area?
GREG SASS: [
00:27:46] I think the last thing is, is come, come pay us a visit. You know, most much of the data we collect and the things that we're able to do are, are collected by the anglers themselves.
And so the compulsory Creel survey and all the great information that we've been able to collect over the seventy-five years. Wouldn't be possible if we didn't have anglers fishing the lakes.
KATIE GRANT: [
00:28:06] Have a question about the research being done here at the DNR? Email us. dnrpodcast@wisconsin.gov and we'll work with our experts to get you an answer.
SARAH HOYE: [
00:28:21] You've been listening to Wild Wisconsin. A podcast brought to you by the Wisconsin DNR. For more great episodes, listen and subscribe to Wild Wisconsin wherever you get your podcasts.