Press release from WI DNR

MADISON, Wis. – Together with Walleyes for Tomorrow, the Wisconsin Department of Natural Resources (DNR) announces the continuation of the walleye reward tag study in the Bay of Green Bay and its major tributaries.

The Bay of Green Bay and its tributaries support a world-class walleye fishery, allowing anglers to catch walleye of all sizes, including trophy-sized fish. The popularity of this fishery continues to be a major draw for anglers locally, statewide and throughout the Midwest.  

The DNR began the reward tag study in spring 2024 and will continue implementing the study with walleye tagging efforts this spring, thanks to funding from Walleyes for Tomorrow. The study aims to better understand the walleye fishery and gain estimates of walleye exploitation rates (i.e., the percentage of the walleye population that anglers harvest each year).

DNR staff will tag up to 5,000 walleyes with yellow floy tags throughout five major spawning areas around Green Bay this spring – Sturgeon Bay and the Fox, Oconto, Peshtigo and Menominee rivers. In addition to the yellow floy tags, 400 red reward tags will be distributed throughout these areas.

What Happens If I Catch A Tagged Walleye?

The fish can be harvested if it is legal to do so (within bag limits, season restrictions, etc.) or released. Any tagged fish not meeting minimum length requirements should be immediately released after collecting the necessary tagging information described below. Please keep the tag intact when releasing any walleyes and follow responsible catch and release practices.

Anglers are encouraged to report all walleyes that are caught with any color floy tag. We ask anglers to report the following information regarding their tagged fish: tag number, tag color, species, length, location caught, date caught and whether the fish was harvested or released.

Reward tags will be red and say, “REWARD $100.” All red reward tags will have a date printed on them, which is the date the reward is valid until. While the tagged walleye does not need to be harvested to receive the $100 reward, anglers must provide proper verification that they caught a walleye with a reward tag. Verification must be done in one of the following ways:

• If harvested, present the physical tag to the DNR.
• If released, take a close-up picture of the tag that includes the three-digit tag number and a picture of the angler holding the walleye with the attached tag visible.

To report your catch to the DNR, email DNRFHGBFISH@wisconsin.gov or call 920-662-5411. To mail in a floy tag from a harvested fish, send it to:

ATTN Fish Biologist
2984 Shawano Avenue
Green Bay, WI 54313

Anglers that report a yellow or green (from previous tagging years) floy tag will receive information about the fish, including date, location, size, sex and possibly age at the time of tagging. Anglers do not need to provide picture verification or mail in the physical tag when reporting walleyes with a yellow or green floy tag.

Reports of captured or harvested tagged walleyes will help the DNR guide walleye management throughout Green Bay and its tributaries by tracking angler harvest, exploitation rate, spawning site fidelity, summer movement patterns and growth rates.

This is the study WFT paid for in 2018 to document the value of Sport Fishing on Green Bay.  We did this in anticipation of the commercial fishing growth in Green Bay.
WFT representatives attended 2 meetings, one in Sturgeon Bay and one in Green Bay in 2018.  Both meetings disturbed us greatly, thus the study.
The DNR has never really referenced the study.
Meredith Penthorn at DNR and she said she would post it on the DNR website to make it a public document.

In an effort to better understand angling in the Bay of Green Bay
watershed and how this identity impacts the state economy, the
authors worked with Walleyes for Tomorrow and the Wisconsin
Department of Natural Resources (WDNR). Since the WDNR

continually examines the catch of anglers through a long-
standing creel survey design that is used to estimate fishing

pressure and success, the data collection effort for this study
piggy-backed upon this creel survey design by distributing
a survey packet to recreational anglers intercepted at boat
launches and shore fishing areas.

The Oshkosh fisheries work unit and Asylum Bay operations staff have completed the 2021 walleye spawning stock assessment. The objectives of the survey included tagging adult walleye to estimate annual exploitation, evaluate size structure, conduct age and growth analyses on male aging samples and evaluate spawning marsh conditions. Survey efforts began on the Wolf River on March 21 and continued through April 5. Water level gauge height at the USGS New London site ranged from about 7 feet on March 21 to 6.2 feet on April 5.

The lack of rain and snow this year led to fairly low water levels on the Wolf River during the peak walleye spawn compared to recent years. Water levels and flow in the main marshes around New London and Shiocton were marginal. Generally, a gauge height of at least 7 feet is needed to provided marginal conditions, with more ideal marsh conditions occurring when gauge height surpasses 8 feet. 

In total, 3,703 adult male and 852 adult female walleye were sampled on the Wolf River. That was near the annual goal of tagging 5,000 in the Wolf River. In addition, 72 adult male and 9 adult female walleye were sampled on the upper Fox River near Princeton. Peak spawning activity was observed throughout the week of March  25 and mostly wrapped up by early April. The strong 2016 year class was well represented during survey efforts, with males ranging 13-15 inches and females ranging 15-18 inches.

Tagging efforts included continuing the reward tag study and the release of 100 male and 100 female reward tagged fish. These tags are worth $100 for anglers that catch and report a pink reward tagged fish. The tag reward for this year’s tags will expire on March 31, 2022 and are being paid for by Battle on Bago. This study will continue to provide more accurate annual exploitation and angler tag reporting estimates. DNR staff also conducted walleye electrofishing surveys on the Upriver Lake and Lake Winnebago.

The objectives of the survey primarily include tagging immature (unknown male or female) and immature female walleye to estimate annual exploitation. Adult males and females sampled are also tagged. Overall, 372 immature, 243 immature female, 119 adult female and 642 male walleye were sampled. Immature walleye sampled mainly ranged 11-14 inches and immature female walleye ranged 14-17 inches.

Anglers can report the catch of a tagged walleye, yellow perch, bass, or northern pike by mailing the catch information to the Oshkosh DNR office (625 East County Road Y, Oshkosh WI 54901), emailing it to DNRWINNEBAGOSYSTEMTAGRETURNS@wisconsin.gov or calling 920-303-5429. If you have any questions about the trawling report or this year’s survey update, please feel free to reach out.

The Wisconsin Department of Natural Resources (DNR) recently published the 2020 Lake Winnebago Trawling Report, which discloses the results of the trawl assessment conducted on Lake Winnebago. This assessment has been conducted annually since 1986, and the main objectives include providing critical information on year class strength of game and nongame fish species, monitoring trends in the forage base and monitoring general population trends of game and nongame fish species. Overall, there were 15 species of young of year (YOY) fish sampled for a total of 79,835 YOY fish caught during the 2020 trawling survey. For adult ­­­fish, there were 18 different species sampled for a total of 42,480 adult fish captured. The 2020 trawling results revealed several highlights, including record catch rates of YOY freshwater drum and yellow perch, a strong crappie hatch and a measurable walleye year class. I hope you enjoy the report.

Nathan Jaksha¹, Daniel Isermann², & Daniel Dembkowski¹

University of Wisconsin-Stevens Point¹, USGS-Wisconsin Cooperative Fishery Research Unit²

Introduction

• Walleye are an important species in Wisconsin that support both recreational hook-and-line and tribal spear fisheries.
• Walleye recruitment has declined in some lakes that previously supported natural recruitment yet has remained stable in other lakes.
• Recent studies suggest that a recruitment bottleneck may be occurring at or before the larval stage in lakes exhibiting declines in natural recruitment.
• Reasons for the contrasting trends in recruitment among populations are unclear, as are mechanisms underlying the recruitment bottleneck in lakes with declining recruitment.
• Differences in prey availability among lakes with different recruitment histories could contribute to the observed trends in recruitment.
• Assessment of larval walleye diets from lakes with different recruitment histories could provide important insight to the role of prey resources in explaining trends in walleye recruitment in Wisconsin lakes.

Objective

Describe diet composition of larval walleyes in northern Wisconsin lakes displaying two different recruitment histories: sustained natural recruitment (S-NR) and declining natural recruitment (D-NR).

Methods – Sampling

• Larval  walleye sampling occurred during 2016 & 2017 on 13 lakes
  • Five of these lakes were resampled in 2018
• Sampling started mid-May each year
  • Continued at 7-10 d intervals until early June
  • Surface temps = 11-16˚C
• Larval walleyes were collected using a 1,000-µm mesh conical ichthyoplankton net.
  • Towed at surface (5 min) at both nearshore (within 100-m) & offshore locations (≥100-m) at night
• Percid larvae identified to species using dichotomous keys
  • Random subset selected for genetic verification of visual species identification using PCR techniques

Methods – Diets

• Gut contents of each fish were removed and diets were quantified using mean percent composition by number of individual diet items.
• Zooplankton items classified to order for adult copepods and genus for cladocerans
• Larval fish encountered in diets identified genetically using qPCR techniques

Results – All Lakes

• Larval walleye collected from 6 S-NR lakes and 4 D-NR lakes (diets summarized in Table 1).
• Guts were removed from 115 larval walleyes (mean TL = 11.4 mm; range = 6.4 –22.0 mm).
• 27% of diets (31 of 115) were empty
• 37% of diets (42 of 115) contained larval yellow perch
• 16% of diets (18 of 115) contained zooplankton

Table 1. Mean percent composition by number and counts of prey items observed in larval walleye diets from all lakes combined.Search:

Showing 1 to 6 of 6 entries

Results – S-NR vs. D-NR Lakes

• S-NR Lakes = 86 larval walleye (diets summarized in Table 2)
  • Larval walleye mean length = 11.3 mm (range = 6.5 -22.0 mm)
  • 38 % of diets (33 of 86) were empty
  • 31% of diets (27 of 86) contained larval yellow perch
  • 20% of diets (17 of 86) contained zooplankton
• D-NR Lakes = 29 larval walleye (diets summarized in Table 2)
  • Larval walleye mean length = 12.4 mm (range = 7.8 -21.0 mm)
  • 28% of diets (8 of 29) were empty
  • 52% of diets (15 of 29) contained larval yellow perch
  • 3% of diets (1of 29) contained zooplankton

Table 2. Mean percent composition by number and counts of prey items observed in larval walleye diets from S-NR and D-NR lakes.

Discussion

• Larval yellow perch were the dominant prey item for larval walleyes in lakes exhibiting both sustained and declining natural recruitment.
  • Extent of piscivorymuch greater than previously assumed
• In general, larval walleyes in S-NR lakes consumed a greater diversity of prey items and more zooplankton than larval walleyes in D-NR lakes.
• Further statistical analyses required to determine if diets and prey availability differed between S-NR & D-NR lakes.

Acknowledgements

• This study was funded by the Wisconsin Department of Natural Resources through the Fisheries Analysis Center at the University of Wisconsin-Stevens Point.
• Jason Gostiaux
• Walleyes for Tomorrow: Research Fellowship

As part of its ongoing effort to increase public access on federal lands, the U.S. Fish and Wildlife Service today announced (news release attached) it is seeking the public’s assistance to develop a list of its managed lands that would benefit from new or increased access routes. 

On March 12, 2019, President Donald Trump signed into law the John D. Dingell Jr. Conservation, Management, and Recreation Act (S.47, the Dingell Act), which directs the Service and other federal land management agencies to develop a priority list of lands that have significantly restricted or no public access where that access could be improved. The public is encouraged to identify national wildlife refuges, fish hatcheries and other lands managed by the Service that meet the complete criteria. 

Comments will be accepted over a 30-day comment period from February 10-March 11, 2020. 

Some of the criteria for nominated lands include: public lands must be managed by the Service and 640 contiguous acres; have significantly restricted or no public access; and be open under federal or state law to hunting, fishing, or use of the land for other public recreational purposes. 

For additional information and a full list of required criteria for consideration as specified by the Dingell Act, visit: https://www.fws.gov/refuges/realty/Public-Access-Nominations.html. 

Commenters are encouraged to review the required criteria and include additional information as to why the parcel should be on the Service’s priority list. Once the comment period closes the Service will evaluate the nominations to determine which lands meet the requirements and considerations specified by the Dingell Act.

A Thesis Submitted in partial fulfillment of the requirements of the degree
MASTER OF SCIENCE IN NATURAL RESOURCES (FISHERIES)
College of Natural Resources UNIVERSITY OF WISCONSIN
Stevens Point, Wisconsin

Many northern Wisconsin lakes that historically supported naturally-recruiting walleye Sander vitreus populations have shown declines in recruitment over the last 10-15 years. Previous research conducted on four northern Wisconsin lakes suggested a recruitment bottleneck was occurring before mid-July in lakes with declining walleye natural recruitment. Effective management of walleye populations involves understanding these recruitment bottlenecks, as potential management solutions may vary in relation to when and why this recruitment failure is occurring. To further assess these recruitment bottlenecks, I expanded on the previous assessment to determine if: 1) timing of a recruitment bottleneck for age-0 walleyes was consistent among lakes with declining
recruitment; 2) abiotic and biotic metrics differed between lakes with declining (D-NR) and sustained (S-NR) walleye recruitment, with a specific focus on the abundance of edible zooplankton and 3) catch-per-effort (CPE) of larval and post-larval walleyes can be used to predict the presence, absence, and relative strength of walleye year-classes indexed by standard fall electrofishing conducted by the Wisconsin Department of Natural Resources and the Great Lakes Indian Fish and Wildlife Commission.

Hadley Boehm was the grad student who did the walleye research under Dan Isermann last year. She graduated, got a job with the Minnesota DNR, and then finished her thesis, a copy of which is attached. The research is continuing….

The short version is: Walleye are spawning, then the fry are showing up in some lakes, and not showing up in other lakes. No fry = no YOY in fall. And nobody knows why.

Click here to read Thesis

We look forward to working with our local DNR staff in not only increasing habitat, but education about the walleye as well with work being done at the Peshtigo River

Photos of
• Anglers lined up in the lower Peshtigo River in the spring.
• A big female. Look closely at the base of the dorsal and you can see a green floy tag.
• Closer up of a floy tag.
• 2012 survey on the lower Peshtigo River. Left to right WDNR fisheries staff Ron Rhode, Tammie Paoli, Rod Lange, Brad Ryan.
• Crew and shocking boat on the lower Peshtigo.
• A walleye with lymphocystis (and a yellow floy tag). In the spring, we get quite a few calls about fish having warty growths on them. Lymphocystis is a viral disease that is seldom fatal that seems to peak in the spring during colder temps and spawning stress…