What are the Clearest Lakes in Wisconsin? The 2021 Report

 

For the best underwater photography, finding clear water with high transparency is essential. So what are the clearest lakes in Wisconsin?  Every year, I consult with Wisconsin's state-wide citizen's lake monitoring group. They're a network of individuals, usually lake-front property owners who monitor and regularly take a variety of water samples from lakes all across Wisconsin.  The data they compile helps to give us a look at how our lakes are doing. 

One of the many tasks lake monitors perform is to take regular Secchi disc readings. This is a universal way of assessing and comparing water clarity.  I'm always interested in knowing which Wisconsin inland lakes are the clearest.  Ordinarily, I rank the lakes that recorded the highest average water clarity for the previous year. This year, I'm looking at lakes that recorded the single highest Secchi disc reading in 2021. Because of Covid-19, not all the usual lakes were sampled at their usual intervals, so we have only the data that was collected. With that in mind, here are Wisconsin's clearest inland lakes and their highest single-day water clarity readings taken in 2021:

1)   Lake Metonga, Forest Co.39.5 feet

2)   Nagawicka Lake, Waukesha Co. 38 feet

3)   Sand Lake, Burnett Co. 35.5 feet

4)   Upper Eau Claire Lake, Bayfield Co. 34.5 feet

5)   White Lake, Marquette Co. 33 feet

6)   Delavan Lake, Walworth Co. 32 feet

7)   Lake Mendota, Dane Co. 30 feet

8)   Pearl Lake, Waushara Co. 30 feet

9)   Forest Lake, Vilas Co. 29.5 feet

10) Big Arbor Vitae Lake, Vilas Co. 29 feet

11) Sugar Camp Lake, Oneida Co. 29 feet

12) Blue Lake, Oneida Co. 29 feet

13) Butternut Lake, Forest Co. 28 feet

14) Lake Owen, Bayfield Co. 27 feet

15) Black Oak Lake, Vilas Co. 27 feet

To see the list from 2020, click here.

What are the Clearest Inland Lakes in Wisconsin? The 2020 Report:

For the best underwater photography, finding clear water with high transparency is essential. So what are the clearest lakes in Wisconsin?  Every year, I consult with Wisconsin's state-wide citizen's lake monitoring group. They're a network of individuals, usually lake-front property owners who monitor and regularly take a variety of water samples from lakes all across Wisconsin.  The data they compile helps to give us a look at how our lakes are doing. 

One of the many tasks lake monitors perform is to take regular Secchi disc readings. This is a universal way of assessing and comparing water clarity.  I'm always interested in knowing which Wisconsin inland lakes are the clearest.  Ordinarily, I rank the lakes that recorded the highest average water clarity for the previous year. This year, I'm looking at lakes that recorded the single highest Secchi disc reading in 2020. Because of Covid-19, not all the usual lakes were sampled at their usual intervals, so we have only the data that was collected. With that in mind, here are Wisconsin's clearest inland lakes and their highest single-day water clarity readings taken in 2020:

1)   Upper Eau Claire Lake, Bayfield Co. 39.5 feet

2)   White Lake, Marquette Co. 36 feet

3)   Middle Eau Claire Lake, Bayfield Co. 35.75 feet

4)   Whitefish Lake, Douglas Co. 35 feet

5)   Blue Lake, Oneida Co. 32 feet

6)   Lee Lake, Oneida Co. 31.5 feet

7)   Black Oak Lake, Vilas Co. 30.5 feet

8)   Forest Lake, Vilas Co. 30.5 feet

9)   Stone Lake, Washburn Co. 30 feet

10) Pearl Lake, Waushara Co. 30 feet

11) Lower Eau Claire Lake, Bayfield Co. 29.75 feet

12) Bass Lake, Oconto Co. 29 feet

13) Smoky Lake, Vilas Co. 29 feet

14) Sugar Camp Lake, Oneida Co. 28.5 feet

15) Upper Nemahbin Lake, Waukesha Co. 28 feet

To see the lake list from 2019, click here. 

What are the Clearest Lakes in Wisconsin? 2019 Report

What are the clearest lakes in Wisconsin?  Every year, I consult with Wisconsin's state-wide citizen's lake monitoring group. They're a network of individuals, usually lake-front property owners who monitor and regularly take a variety of water samples from lakes all across Wisconsin.  The data they compile helps to give us a look at how our lakes are doing. 

One of the many tasks lake monitors perform is to take regular secchi disc readings. This is a universal way of assessing and comparing water clarity.  I'm always interested in knowing which Wisconsin inland lakes are the clearest.  Ordinarily, I rank the lakes that recorded the highest average water clarity for the previous year. This year, I'm looking at lakes that recorded the single highest secchi disc reading in 2019. Here are Wisconsin's clearest inland lakes and their highest single day water clarity readings taken in 2019:

1)   Pine Lake, Waukesha Co. 52 feet
2)   Lake Metonga, Forest Co. 37 feet
3)   Maiden Lake, Oconto Co. 35 feet
4)   Wazee Lake, Jackson Co. 34 feet
5)   Sugar Camp Lake, Oneida Co. 33 feet
6)   Whitefish Lake, Douglas Co. 31 feet
7)   Lake Lucerne, Forest Co. 31 feet
8)   Deer Lake, Polk Co. 30 feet
9)   Crystal Lake, Marquette Co. 29 feet
10) Stone Lake, Washburn Co. 29 feet
11) Lake Owen, Bayfield Co. 29 feet
12) Blue Lake, Oneida Co. 28 feet
13) Smoky Lake, Vilas Co. 28 feet
14) Millicent Lake, Bayfield Co. 28 feet
15) Big Portage Lake, Vilas Co. 28 feet

To see the lake list from 2018, click here. To see the lake list from 2017, click here. To see the lake list from 2016, click here.To see the lake list from 2015, click here.  To see the lake list from 2014, click here.  For the lake list from 2013, click here.  And for the 2012 list of clear lakes, click here.

Walleye 911: The Walleye & Bullhead Connection

Juvenile Walleyes in Lake Metonga (C)Engbretson Underwater Photo

How Bio-Manipulation Saved the Walleyes of Wisconsin’s Lake Metonga

by Eric Engbretson

Something was going very wrong in Lake Metonga. The 2,000-acre lake in Wisconsin’s north woods had been a successful walleye lake for decades, but by the late 1990s, natural reproduction and walleye recruitment had slowed to a trickle. To make matters worse, by 2004, the adult walleye population had sharply declined.  Spawning habitat was excellent, but young fish, either stocked or natural, were not surviving to adulthood.

 

Mike Preul, fisheries biologist for the Mole Lake Sokaogon Chippewa Community has been involved with fisheries work on Lake Metonga for twenty years.  He took a closer look at the lake to see what changes might explain why walleyes were suddenly having such a rough time. 

The fish community in Lake Metonga had always included black bullheads, but now fishermen were telling Mike how often they were catching the small catfish. “We were doing some routine electro shocking one day and when the stunned fish floated to the surface, all you could see were yellow bellies. That’s when I knew there was a problem”. The abundance of bullheads had become enormous. “We did some simple math and calculated what a bullhead eats in a year. They were taking up a lot of space in the system and stressing the available forage for walleye.”  The theory was they were outcompeting walleyes for important forage at critical times when walleyes need an abundance of specific-sized food.  “We knew stocking wasn’t working, so the idea was that if we could create a kind of void, the walleyes might rush in to fill it.”

Like many fisheries managers, Mike’s resources were limited, and he privately wondered if this was really a battle he could win. His plan was to create conditions where walleyes could thrive, and that meant doing something about how much of the lake’s biomass was tied up in bullheads.  His plan reversed the fortunes of the lake’s walleyes almost overnight. 

In the spring of 2008, Mike began the first of what would become an annual bullhead removal on Lake Metonga. The work was labor-intensive. “At first we set fyke nets, but the fish weren’t moving into them in sufficient numbers, so the decision was made to electroshock for bullheads”.  Mike’s crew worked until their arms ached, shocking and netting the whiskered fish out of the lake. By summer’s end, they had removed 13,337 pounds of bullheads. All the fish were donated to the public, to food banks and to nearby wildlife rehabilitation centers for the feeding of raptors. 

Into the newly created void, Mike stocked 5,000 large fingerling walleye.  The next spring, another 6,216 pounds of bullheads were removed and over two million walleye fry were stocked. But this time, something different happened.  Substantial numbers of young walleyes survived from the two years of stocking and began to show up and be counted in fall recruitment surveys. 

At first there seemed to be no end to the steady stream of stunned bullheads that rose to the surface every time Mike’s crew flipped on the electrodes of his shocking boat. But gradually, fewer and fewer bullheads appeared, and it took longer to fill up the tubs on the boat with fish. This process became a ritual every spring on Lake Metonga and by 2012 the total catch rate had dropped by 87%.  During the same time, the abundance of walleye fingerlings was steadily increasing.

During 2011 there was a large year class consisting of purely naturally reproduced fish. With the resurgence of naturally reproduced walleye, stocking was no longer needed after 2012. With bullhead numbers reduced and in better balance with other fish, walleye production in Lake Metonga boomed. Eventually, both natural recruitment and adult walleye density reached historic highs. For Mike Preul, this felt like the kind of victory that fisheries managers too rarely experience.  “I won’t lie to you, it was a lot of hard work some days, but the results have been so amazing.”

Today Mike Preul spends only a few days each spring shocking for bullheads. It’s become pure maintenance now, like mowing his lawn. “As long as they don’t get out of control, I think we’re good”, smiles Mike.  Walleye production has it’s up and down years but has remained reliable overall.  What Mike learned on Lake Metonga could fill a book. His bio-manipulation method of removing bullheads to rebuild embattled walleye populations was successfully employed on Patten Lake in nearby Florence County and worked like pure magic. When that lake’s over-abundant population of bullheads were severely reduced, the walleyes quickly came back in record-setting density.

Keeping walleye lakes healthy and productive is an ongoing issue, and all lakes face their own unique challenges. Overall, there likely aren’t a great number of walleye lakes affected by bullhead populations, but where such lakes exist, Mike Preul’s pioneering work is one silver bullet that fisheries managers can now add to their arsenal. 

(For further information, questions or comments about his work, Mike Preul can be contacted at mike.preul@scc-nsn.gov)

What are Wisconsin's Clearest Lakes?

What are the clearest lakes in Wisconsin?  Every year, I consult with Wisconsin's state-wide citizen's lake monitoring group. They're a network of individuals, usually lake-front property owners who monitor and regularly take a variety of water samples from lakes all across Wisconsin.  The data they compile helps to give us a look at how our lakes are doing. One of the many tasks lake monitors perform is to take regular sechi disc readings. This is a universal way of assessing and comparing water clarity.  I'm always interested in knowing which Wisconsin inland lakes are the clearest.  Here are the lakes that recorded the highest average water clarity in 2018. In short-here are Wisconsin's clearest inland lakes and their average water clarity in 2018:

1)   Lake Wazee, Jackson Co. 30.3 feet
2)   Whitefish Lake, Douglas Co.  27 feet
3)   Smoky Lake, Vilas Co. 26.7 feet
4)   Paya Lake, Oconto Co. 26.6 feet
5)   Black Oak Lake, Vilas Co. 26.5 feet
6)   Pine Lake, Waukesha Co. 25.5 feet
7)   Lake Metonga, Forest Co. 25.5 feet
8)   Presque Isle Lake, Vilas Co. 25 feet
9)   Mildred Lake, Oneida Co. 24.3 feet
10) Blue Lake, Oneida Co. 23.25 feet

To See the lake list from 2017, click here. To see the lake list from 2016, click here.To see the lake list from 2015, click here.  To see the lake list from 2014, click here.  For the lake list from 2013, click here.  And for the 2012 list of clear lakes, click here.

Can you Recommend a Good Underwater Camera?

Scott P. wrote to me recently asking about Spearfishing and Underwater Photography:

“Been spearfishing for a while. Wanting to get into underwater photography. Any tips on a decent, but simple to operate camera? – Scott P.”

As an underwater photographer, I can always tell when a lake or a river gets a certain amount of spearfishing pressure because the fish become very wary of divers. They learn to avoid us. In waters where spearfishing doesn't happen, the fish tend to be friendlier and you can approach them closely and quite easily.  I mention this to you because if you start doing any underwater photography, you will definitely want to avoid lakes you spearfish and vice versa.

Spearfishing is outlawed in most counties of the northern Wisconsin where I spend a lot of time so luckily I don't encounter fish that are inherently frightened of divers. When I go to southern Wisconsin, or even Lake Michigan, it's a different story. When photographing fish, ideally you want to be about 2 feet away from them. As you can imagine, on lakes where spearfishing occurs, the fish never let you approach that closely.

There's a lot of digital cameras on the market that work well underwater. As a rule, the more expensive they are, the better they perform. If I had to single out one to recommend to you, I'd say go with a GoPro Hero. The latest one is the Hero 6, but the Hero 5 and Hero 4 models are also excellent. You'll be able to get some nice photos with any of these models along with truly exceptional video. You won't be disappointed. Trust me. They're small, easy to use and the results are very impressive. Both the GoPro Hero 5 and Hero 6 are waterproof to 33 feet. The Hero 4 requires a waterproof housing.  All the GoPro models shoot exceptional videos. However, their still photo capabilities are limited to 12MP images, which is a little less than we like to use for professional purposes.  All that means is that unless you’re a professional photographer, the images from the GoPros will be more than satisfactory.

Thanks for your question Scott.  If you have a question about fish, underwater photography or any related subjects, feel free to email me here.

From The Mailbox "How Do I Find Fish Cribs?"

I thought it would be fun to share with you some of the questions I get about the underwater environments I visit, the fish I see, the structure fish are attracted to, and other observations I make when I’m photographing fish underwater.  (If you have any questions, fire away, and I’ll do my best to answer them.)

Today’s email comes from George Mycroff of Antioch, IL. who writes: 

”Hi Eric.  I've been looking for a source for 'marked' crib location maps for various lakes I fish in Northern Wisconsin.   Very hard to come by!  While the 'primary' purpose of fish cribs is to promote the growth and proliferation of fish species in a lake,  the secondary purpose is that it's an excellent spot to find fish....The reasoning goes, 'find the cribs, you'll find the fish'!  So my question is how do I find 'fish cribs', marked on a DNR 'topo' map or 'GPS' coordinates?  If the DNR installs them don't they use permits and note the location for later study? So wouldn't they be 'public record' anyone should be able to obtain?  WHERE? I've checked with the DNR, they say since 'fish cribs' don't last over years, they may not have records, or the locations move from year to year. I’ve checked the internet, but have not had much luck finding 'marked' fish crib maps for, the lakes I'm interested in.  Any comments or suggestions or recommendations from you would be greatly appreciated!” 

George, Just to be accurate. Fish cribs DO NOT promote growth and proliferation of fish. This has been studied extensively, and fish cribs do not lead to more fish in the lake. If anything, they decrease over-all abundance because fish tend to be concentrated and can be over exploited. I don't spend a great deal of time around fish cribs myself.  When I'm taking pictures, I prefer more natural backgrounds like plants or sunken trees.  It just looks prettier in photos than a big cube of wood. Also, many cribs are poorly constructed or deployed in bad locations. Therefore, finding cribs doesn't at all mean that you'll also find fish.  I'd go as far to say that most of the cribs I've seen hold few if any fish. It depends on where they were placed and how they were constructed. 

Here's what I've noticed with marked fish crib maps.  Usually, those cribs were placed decades ago and have fallen apart.  Meaning, the wood is still on the lake floor, but the structure no longer has any vertical height and consequently no longer attract fish.  The cribs I occasionally visit aren't on any maps I've seen.  So I wouldn't put too much stock into the credibility or integrity of maps.  The best info comes from fisherman who know where the cribs are. They can usually direct you to the most active ones.  They share this info readily with me, but perhaps are more tight-lipped with fellow fisherman. 

The DNR topo maps that you refer to are a notoriously unreliable resource for finding any structure that was placed. So many of these maps were drawn in the 50s and 60s.  I think if I were you, I'd just spend some time slowly motoring around the lakes in the 10-20 foot depths and looking at your electronics.  I know this can be a tedious way to locate cribs, but if you're looking for a short cut, the DNR maps aren't going to help you.  Another trick is take a drive around the areas lakes before the ice goes out. You'll be able to spot any new cribs sitting on the ice and note the location.  But I don't expect you'll see many these days.  They aren't as popular as they once were.

Wisconsin DNR has never marked GPS coordinates of the cribs and made them public. Other states do this religiously.  WDNR is now of the opinion that fish cribs are detrimental to fish populations, and no longer deploy them. They now favor fish sticks, which actually do help to grow fish.  All the reasons the DNR gave you for why they can't help you are valid in my estimation. Cribs do disintegrate and move, and they didn't have GPS back when they were building and placing them.  Thanks very much for your question George. 

I love talking about the lakes, fish and of course underwater photography. If you have a question, feel free to email me.

Wisconsin's Shrinking Panfish

Large Bluegill

Often, when I’m coming out of lakes in my scuba gear with cameras, I’m approached by fisherman who ask me “if I saw any big ones?”  The answer is usually yes and no.  As you might expect, the large fish I tend to see are species where catch and release fishing is the norm.  It’s common to see giant smallmouth bass and large muskies, because while fishing pressure is often heavy on these species, they’re almost always released to grow bigger.  Conversely, species that don’t enjoy high levels of catch and release and are kept for the dinner table like walleyes, bluegills, crappie, and yellow perch have a harder time reaching their full potential.  So I don’t often see large panfish with regularity.  I still encounter some very large walleyes because regulations like slot limits that are in place in many waters help to keep fish in the system longer which means they have an improved chance to reach larger sizes. 

So how much does harvest affect fish sizes?  I think it’s pretty significant. 

Liberal bag limits on panfish for example will likely not lead to decreased abundance, but they do cause poor size structure.  When bluegills get around 7 inches, and are at a size worth cleaning and eating, very few of them are released.  So the population gets further compressed into mainly fish that are 6 inches or less.  It tends to be the same way with yellow perch and crappie.  The problem is not the total amount of the harvest, but the selective harvest of what fish managers call “quality fish”. 

Since larger panfish are less common than smaller, younger fish, they often can’t sustain this extra selective targeting.  While many fisherman have long encouraged letting the big ones go and keeping a few smaller ones for the frying pan, it doesn’t seem like this is happening on a scale that could make any real difference.  Quality panfish are being targeted and harvested and the numbers of larger, older fish have plummeted. 

I spend 70-90 days a year in lakes taking fish pictures.  That’s a lot of time underwater where I observe many fish.  In an average year, in dozens of different lakes, I might see only one or two 10 inch bluegills a year.  That’s how rare they are.  Perch of the same size are also rare as are large crappie.  I think it’s important for fisherman to realize that when they catch an 10 inch bluegill and put it on the stringer, they are very likely removing the largest bluegill from that lake.  On smaller sized bodies of water, this is most certainly true.  You might erroneously think there must be many others of that size, so taking that single large fish wouldn’t be reason to pause.  But if you could be with me in these lakes and see what I see, you would realize how truly rare and special these large panfish are.  If you knew you were removing the largest fish of that species from the lake, would it make any difference to you? 

Fish managers are aware of the declining numbers of larger panfish available in Wisconsin Lakes, and have been working on new panfish regulations that would address overharvesting of quality fish.  When I asked Andrew Rypel, the top panfish expert with Wisconsin’s DNR about the problem, here’s what he told me:

“There is no doubt that anglers probably affect bluegill size structure more than any other factor in Wisconsin. However in our statewide surveys of angler attitudes and public hearings, we were unable to find public support at this point in time for changing the statewide panfish regulation, but we did find support for doing something about problem lakes where we thought angling was the problem. The adaptive panfish management plan is definitely not a permanent solution to broad-scale overfishing of panfish, but it does allow us to conduct a large-scale science-based study that will allow us to learn more about conservation management of all three of our big panfish species. It's unique among approaches taken in other states (almost all of which still have only high bag limits) and allows for the potential to manage lakes in the future on more of a lake-specific basis. So in a sense, Wisconsin is becoming a leader on this topic, albeit on a limited basis. However, I believe the results of this work will be helpful to our managers in the near future. For example, some lakes can probably take more harvest sustainably, however others can tolerate only very little harvest. I'll bet you could take a pretty good guess at which lakes might fall into these categories based on your knowledge of underwater habitats, lake fertility and fish abundances. It is indeed amazing to see unfished bluegill populations - to see the full complement of ages in their population.  It would be nice to have some populations like this in Wisconsin that weren't in the middle of nowhere, and only have size-structures like this because people cannot access the lakes. However, we are taking a step in the right direction, and my sense is that most anglers want to do the right thing for future generations.”

Twenty Years of Underwater Observations: What's Changed?



2015 will mark my agency’s 23^rd year of photographing freshwater fish, underwater in the wild.  As I thought about that, I began to reflect on two trends I’ve noticed over the past two decades, especially in lakes in Wisconsin and Northern Michigan where I live.  A few things stand out regarding fish sizes and abundance and general lake quality. 

Water Clarity:

As an underwater photographer, water clarity is critically important for getting good images.  Because of that, we make it our business to know where the clearest waters are.  One disturbing trend over the past 20 years is that we seem to be losing many of our historically clear lakes in Wisconsin.  More than a dozen lakes that were once very clear are no longer suitable for underwater photography because they simply are no longer clear enough.  Whether it’s because of run off, phosphorus overload or natural eutrophication is unknown.  But since these dramatic changes have occurred over such a short period of time, it suggests that the causes are not natural and are probably indications of damage we as lake users are facilitating.  On the other hand, there are also lakes that were once turbid or had poor water clarity that are now excellent.  The bad news is that virtually every lake that has significantly improved water clarity, it’s because of the presence of zebra mussels.  That may be a nice byproduct for snorkelers and divers, but the expansion of invasive species may also cause long-term negative consequences that aren’t as desirable as clearer water.

Changes in Fish Size and Abundance:

In Wisconsin’s inland lakes I’ve noticed some real changes in the last twenty years in fish abundance and sizes. In the interest of brevity, rather than detail and discuss each one at length here, I’ve decided to instead post a chart of what my personal observations have been over the past two decades. 

Table 1 Change in abundance and average size of Wisconsin fish species I've observed: 1993-2014

SPECIES	ABUNDANCE	AVERAGE SIZE
Muskie	Unchanged	Unchanged
Northern Pike	Decreased	Decreased
Walleye	Increased	Increased
Largemouth Bass	Increased	Decreased
Smallmouth Bass	Increased	Increased
Yellow Perch	Decreased	Decreased
Bluegill	Unchanged	Decreased
Black Crappie	Unchanged	Decreased
Rock Bass	Decreased	Decreased

It’s interesting to note that many of my personal and subjective observations regarding fish abundance and size structure mirrors what Wisconsin DNR fish biologists have also found over this same time period.  Walleyes and Smallmouth Bass are doing better these days but panfish in general are probably being overexploited in many areas, especially what fish managers consider to be quality fish.  (The Wisconsin DNR is in the early stages now of implementing new panfish regulations that hopefully will reverse a 70 year long trend of ever- increasingly smaller fish.)

 

The Future:

 

So what does these mean for us?  For someone like me who’s trying to photograph large gamefish underwater or fisherman who like to catch them, it means that in many cases, there are fewer trophy fish swimming in Wisconsin waters than there used to be.  Today, for me, it’s easier than ever to encounter and photograph nice-sized smallmouth and walleyes, but it’s getting harder and harder to find larger pike and quality sized panfish.  The future isn’t necessarily a bleak one however.  It’s my hope that we can turn this around.  Today, with camera phones being ubiquitous and replica mounts being both stunning and affordable, there’s little reason not to release not just the trophies but ALL the larger fish we catch.  If these same trends continue for the next twenty years, as fishermen, we’ll have no one to blame but ourselves.

What are Wisconsin's Clearest Lakes? 2014

I was talking to Jennifer Filbert at the Wisconsin DNR the other day. Jennifer manages the data for the state-wide citizen's lake monitoring group.  They're a network of individuals, usually lake-front property owners who monitor and regularly take a variety of water samples from lakes all across Wisconsin.  The data they compile helps to give us a look at how our lakes are doing. One of the many tasks lake monitors perform is to take regular sechi disc readings.  This is a universal way of assessing and comparing water clarity.  I was interested to know which Wisconsin inland lakes were the clearest.  Jennifer sent me a spreadsheet of some really comprehensive data and I thought it would be interesting to pass this along.  Here are the lakes that recorded the highest average water clarity in 2014. In short-here are Wisconsin's clearest inland lakes and their average water clarity in 2014:

1)  Pine Lake, Waukesha Co. 31 feet
2)  Black Oak Lake, Vilas Co. 30 feet
3)  Hart Lake, Bayfield Co. 30 feet
4)  Whitefish Lake, Douglas Co. 30 feet
5)  Bass Lake, Washburn Co. 30 feet
6)  Des Moines Lake, Burnett Co. 27 feet
7)  Lake Owen, Bayfield Co. 25 feet
8)  Maiden Lake, Oconto Co. 25 feet
9)  Lake Millicent, Bayfield Co. 25 feet
10) Sugar Camp Lake, Oneida Co. 24 feet

To see the lake list from 2013, click here.  For the 2012 list of clear lakes, click here.

Engbretson Underwater Photography Featured on Minnesota Bound Television Show

It was very cool to have Ron Schara do a little feature piece on our underwater photography on the latest episode of the Minnesota Bound television show.  I thought Ron did a nice job of telling my story and showing what an average day "at the office" is like. To see the video, click on the picture above, or go to this link.

Fish Sticks-The Habitat Management Tool That's Giving Wisconsin Lakes A Make-Over

 

Fish Sticks are assembled on lake ice over the winter. (DNR Photo)

In pre-settlement times, the near shore areas of all of Wisconsin’s lakes were filled with vast amounts of fallen trees.  Due to natural decay and storms that toppled large trees into lakes, our waters contained impressive amounts of timber that provided important habitat for fish and other species.  Today, those natural shorelines and their abundance of downed trees can only be found in a few places.  Lakes like those in Michigan’s undisturbed Sylvania Wilderness Area for example, give us a glimpse of the way all our lakes looked at one time.

As Wisconsin was settled and lakes were developed, shoreline trees were removed to make swimming beaches or to create an “uncluttered” look.  Large trees still growing along the shores were cut down to provide vistas of the lake for home owners to gaze at from their cottage windows.  In a short period of time, most of the wood on Wisconsin’s lakes was gone, eliminating a critical habitat element important to a wide variety of animals who made their homes in or near the lakes.

Today, we recognize the damage we’ve done by removing trees and interrupting the eons old process that replenished our lakes with a constant source of wood.  While it may take hundreds of years to restore our lakes to begin to resemble their original state, one innovative idea is jump-starting the process.  Referred to as “Fish Sticks”, it’s a way to move wood back to our lakes that’s been lost.  Fish sticks were made popular in Wisconsin by Bayfield County Fisheries Biologist Scott Toshner.  He’s worked on more than twenty fish sticks projects in the past four years.  "People tend to clean up their shorelines and remove fallen trees," said Toshner. "Sometimes the trees never get the chance to naturally fall into the water because lawns have taken over eliminating trees, shrubs, and ground cover. Fortunately, some northern Wisconsin communities are taking action to turn back the clock and restore the habitat on which fish, frogs, turtles, bugs, songbirds, ducks, and other critters thrive. Not only that, but they're good for water quality and shoreline protection, too."

Last year, a similar project, called “tree-drops” began on Florence County’s Lake Emily.  Tree drops are helpful but differ in that they usually involve single trees.  While their impact is important, a single tree can’t do the same job as multiple fish sticks.  Dr. Mike Bozek, formally of UW-Stevens Point, has studied this distinction.  “Submerged trees located closer to other submerged trees result in greater numbers and diversity of fish compared to individual trees. Larger numbers of submerged trees create a mosaic of habitats over greater shoreline areas than single trees do. This underscores the importance of riparian areas. We need to manage entire riparian areas and develop complex littoral zone habitats, not just individual trees.” 

As science has begun to better understand the importance of woody habitat in lakes, one type of habitat enhancement that’s been used on Wisconsin’s lakes for generations is on the way out.  In recent years, Fish cribs, have fallen out of favor with fish managers.  New studies show it’s a poor substitute for more natural and legitimate types of fish habitat like fish sticks.   "With the fish cribs, the one thing you kind of miss with them is the link between the near shore area where a lot of these fish spawn and spend their lives as juveniles ... [With fish sticks] the wood in this near shore area may be a missing link in terms of habitat in some of these lakes," Toshner said. 

To further illustrate the difference between single tree drops and fish sticks complexes, we can look to Bony Lake in Bayfield County.  This 191 acre lake was one of the first to employ fish sticks.  To date, more than 400 trees have been added to the lake, and they’re not done yet.  This may seem like a whole lot of wood, but in truth, it’s only a fraction of what the lake would have contained had shoreline property not been radically altered by development. Toshner hopes that as users of lakes, we’ll redefine our idea of what beauty is and discard our desire to create white sandy beaches and instead embrace the wild, unorganized, and natural look of shorelines comprised of fallen trees.  “Fish sticks projects are paying off in northern Wisconsin lakes by providing critical habitat for fish and insects, birds, turtles and frogs," says Toshner. “Beaches are really ecological deserts which don’t support any habitat or sustain any life”. 

A new streamlined permit available from the state and an easy step-by-step guide for fish sticks is now available from the Wisconsin Department of Natural Resources.  This will help lake associations or individuals get started with their own lake improvement projects that incorporate fish sticks.  Scott Toshner is excited about the changing landscapes of our lakes and is optimistic about how as stewards we’ll make better decisions in the future.  "If people can see that trees in the near shore area are a valuable resource, they're less likely to remove a tree that might fall in along their own shoreline."

What are the Clearest Lakes in Wisconsin? 2013

I was talking to Jennifer Filbert at the Wisconsin DNR the other day. Jennifer manages the data for the state-wide citizen's lake monitoring group.  They're a network of individuals, usually lake-front property owners who monitor and regularly take a variety of water samples from lakes all across Wisconsin.  The data they compile helps to give us a look at how our lakes are doing. One of the many tasks lake monitors perform is to take regular sechi disc readings.  This is a universal way of assessing and comparing water clarity.  I was interested to know which Wisconsin inland lakes were the clearest.  Jennifer sent me a spreadsheet of some really comprehensive data and I thought it would be interesting to pass this along.  Here are the lakes that recorded the highest average water clarity in 2013. In short-here are Wisconsin's clearest inland lakes and their average water clarity in 2013:

1)   Black Oak Lake-Vilas Co.-37 feet
2)   Pine Lake-Waukesha Co.-27 feet
3)   Maiden Lake-Oconto Co.-26 feet
4)   Keyes Lake-Florence Co.-25 feet
5)   Whitefish Lake-Douglas Co.-25 feet
6)   Eagle Lake-Bayfield Co.-24 feet
7)   Lake Metonga-Forest Co.-23 feet
8)   Lake Lucerne-Forest Co.-23 feet
9)   Stormy Lake-Vilas Co.-23 feet
10) Blue Lake-Oneida Co.-23 feet
11) Bolger Lake-Oneida Co.-23 feet
12) Lac Courte Oreilles-Sawyer Co.-22 feet
13) Lake Owen-Bayfield Co.-22 feet
14) Millicent Lake-Bayfield Co.-22 feet
15) Deer Lake-Polk Co.-22 feet

For the 2014 lake list, click here.  For the 2012 list, click here.

Lake on The Brink-The Unexpected Consequences of Treating Eurasian Watermilfoil

In 2012, Greg Matzke, a fisheries biologist for the Wisconsin Department of Natural Resources, made a startling discovery on Florence County’s Lake Ellwood. During a comprehensive fish survey which included spring, summer and fall netting and electrofishing surveys, Matzke discovered that all of the lake’s largemouth bass were older than 5 years of age, with approximately 91% of the largemouth bass population being at least seven years old.  The absence of younger fish indicated a recruitment failure for a number of years.  Such failures in largemouth bass recruitment over multiple years are unprecedented in the state of Wisconsin. 

“The current largemouth bass population is in serious trouble,” Matzke reported. “It appears that natural reproduction of largemouth bass has not occurred since 2007. As these older/larger fish move through the population, a significant reduction in largemouth bass abundance will take place, with the potential for the complete loss of this species of fish unless the current situation changes.”

Matzke next began looking at the lake’s panfish population.  What he found was stunning. Overall, the lake’s panfish abundance had fallen an estimated 75% in just the last 10 years, with bluegill and rock bass abundance down an estimated 65% and 89% respectively, showing that these populations also appear to be collapsing. Intense sampling throughout 2012 found only a single black crappie under six years of age, showing another alarming recruitment failure in several consecutive years. When Matzke analyzed the ages of Lake Ellwood’s northern pike population, the results were even more disappointing: There were no pike under the age of eight!  

Matzke stared at the data he had collected. His department had never seen a mystery like the absolute and complete recruitment failures of native northern pike, black crappie, and largemouth bass (along with significant reductions in recruitment of other panfish populations). He shared his findings with other fisheries professionals across the state and they all said the same thing.  They had never seen a collapse like this in their careers. Matzke and his team scrambled to collect more data and tried to find a cause that could have brought the fish to the brink of extirpation in Lake Ellwood. Surveys from 2002 had shown normal abundance, size structure, growth, and recruitment in all of these species. What had happened in the last ten years that was preventing fish from successfully reproducing? 

The only thriving species of game fish in the lake were smallmouth bass. Their abundance and size structure had grown in the last decade and recruitment was high.  This suggested that the problem was targeting specific species of fish. Because Lake Ellwood’s smallmouth bass were doing so well while the other species were collapsing, the focus turned to the lake’s historically sparse but important aquatic plant community. All the species showing recruitment failures are highly dependent on aquatic vegetation for spawning as well as cover and food for their young. Matzke observed that smallmouth bass seem to be different. “The fact that this species was not affected by the reduction in plant life,” he said, “is not a major surprise since as a species smallmouth bass are less dependent on aquatic vegetation.”

 

The Smoking Gun

Eurasian Water Milfoil was discovered in Lake Ellwood in 2002. Herbicide treatments began in 2003 and increased every year. By 2007 recruitment of northern pike, largemouth bass and black crappie had come to an end. “When I started to analyze the data it was strikingly obvious to me that there are some problems associated with the herbicide”, said Matzke. When he graphed the fish abundance (by year class) over the last decade and overlaid it with a graph showing yearly herbicide treatments, he found what he believed was a critical connection.  Fish numbers fell as the amount of herbicide increased.  Interestingly, in the year following a relatively low application of herbicide, young bluegill (and black crappie to a much smaller degree) began to appear again, but their numbers are still very low and they will likely disappear before they reach age 2.

 
“We still wonder which stage of reproduction has failed in these species”, says Matzke. “Aquatic vegetation plays a major role in spawning site selection and in the survival of eggs and fry. Plants are also the source of primary production providing food and habitat for young fish and prey items, including invertebrates and minnows. It seems likely that one or all of these important phases of reproduction are dwindling in Lake Ellwood.”

On April 17, 2013 Matzke met with the Lake Ellwood Association to reveal his data and conclusions. He told the group, “The main cause for failed northern pike, largemouth bass and black crappie recruitment (along with the massive reduction in panfish abundance) appears to be the loss of aquatic vegetation.” The 2-4-D herbicide used on Eurasian watermilfoil had been successful in reducing the abundance of this invasive species significantly. Conversely, other native plants were also harmed by years of chemical treatment. Matzke said he has no reason to believe the chemicals have directly caused a failure in reproduction of any species of fish in Lake Ellwood. However, Matzke does believe that the chemicals have indirectly caused recruitment failure by eliminating too many of the aquatic plants young fish need in order to survive.  Matzke has called for a change in the way the Lake Ellwood Association has been managing the lakes aquatic plants.  He recommended that further chemical treatments for milfoil be stopped.

“First and foremost,” says Matzke, “we need to promote and strengthen aquatic vegetation in Lake Ellwood.” He stresses the role of aquatic vegetation in spawning and concludes that the loss of vegetation (including the invasive milfoil) has almost certainly wiped out a great deal of forage for young fish.

It seems that milfoil treatments controlled the invasive plant but also jeopardized the health of the lakes fishery. Today the lake contains a dwindling and rapidly aging population of largemouth bass, black crappie, northern pike, and bluegill. Matzke hopes the plants will come back in time for the remaining old fish to produce at least one year class before they die. If that doesn’t happen, many fish populations will likely be extirpated from Lake Ellwood. New fish can be stocked, of course, but the lake would lose the unique genetic lineage of the fish that have lived there for thousands of years.

 

The Future

Could chemical herbicide treatments for Eurasian watermilfoil be reducing fish recruitment in other lakes? None of the other lakes that have been receiving chemical treatments have had their fish populations surveyed this intensely. Large scale recruitment problems due to loss of important plant cover could be taking place throughout the region where the invasive plant is now being fought. There is no way to know if this is happening, and frankly, up until now, there has been no reason to find out.  Fisheries experts around the state are only now learning of Matzke’s findings on Lake Ellwood. In the future, they will likely start paying more attention to fish recruitment on lakes treated for Eurasian watermilfoil which would allow the Department of Natural Resources to determine whether this crisis is an isolated instance or a more widespread problem. 

In the meantime, it’s a race against time for Lake Ellwood’s native fish. The question remains: Will the plants come back in time to save these fish populations?

Read this story in In-Fisherman Magazine here.

(Note: An updated, follow-up article (Back From The Brink-How Lake Ellwood, Once Doomed Is Being Rescued), from May 2014 can be viewed by clicking here.)