seasonal movements of walleye in lake eau claire · seasonal movements of walleye in lake eau...

Seasonal Movements of Walleye in Lake Eau Claire

Walleye Tracking Final Report

Dominick Forseth: Wildlands School of Science Research Student

Alex Sobotta: Wildlands School of Science Research Student

Wildlands School of Science Research

S1 County Highway K

Fall Creek, WI 547422

Table of Contents

(Page)

1. Introduction…………………………………………………………………………..3

2. Purpose of the Project...............................................................4‐5

3. Timeline…………………………………………………………………………………6

4. Tagging the Walleye………………………………………………………………6‐7

5. Transmitters………………………………………………………………………….7‐8

6. Locating the Fish…………………………………………………………………..8‐9

7. Aerators……………………………………………………………………………….9

8. Arc Gis and Arcmap……………………………………………………………..9‐10

9. Continuation of this project………………………………………………..10

10. Lake Eau Claire Maps…………………………………………………………..11

11. Fish Locations……………………………………………………………………..12‐15

Introduction

Lake Eau Claire is a 900 acre man‐made lake located 8 miles north of

Augusta, Wisconsin. The Lake has three public boat landings, one on the north

side, one on the southeast side named skid row, and one on the southwest side.

Also, there is one beach located on the north side of the lake. Lake Eau Claire is

great for recreational boating and fishing. The Lake is well known for great fishing

for panfish and game fish alike. The Lake Eau Claire Association is constantly doing

things to improve the lake’s health as well as protecting and increasing lake’s

biological diversity. Such as dropping fish cribs and falling trees into the water to

make more habitats there for creating more space for more fish to live and grow.

The lake association has also dredged out parts of the river flowing into the lake

and adding sand traps to help stop the sand and sentiment from flowing into the

lake. Another project the association has been working on is putting aerators in

the lake which oxygenates the water which creates habitat that until now was

uninhabitable by fish.

Some Wildlands students wanted to do a telemetry project on fish to

figure out seasonal habits and habitats related to the seasons. With some thought

the students decided to put five transmitters on northern pike. We it came time

to fund it one the teachers contacted the lake association and the lake

association thought it would be more beneficial to their needs if the students

tracked walleyes and would give more scientific results if the students did ten

walleyes. Eight walleyes were tagged in May of 2015 and have been tracked once

a week by students since then. The data that was collected has given the students

and the lake association a wealth of information. The lake association used the

data the students collected to prove that the aerators are doing what they were

intended to do so they can continue to get funds for the aerators. The students

got lots of information on where the walleyes spend their time throughout the

seasons.

Purpose of the Lake Eau Claire Walleye Tracking Project

"How does Lake Eau Claire benefit from this project?"

"I think the lake benefits from your project in several ways. First, we are

able to study specific locations of walleyes over the soft water period and that

improves our understanding of what type of water and cover the fish prefer.

Second, we are able to watch geographical movements of the walleyes from

spring to fall. This should help us best choose locations to add our half‐log fish

structures (cribs). And, third, with the addition of the new aeration system, we

now have the opportunity to see what if any influences the air bubblers have on

the location and survival of walleyes in the lake." ‐ Fred Poss (Lake Eau Claire

Association member)

"The people of Lake Eau Claire community are interested in improving and

protecting their lake. An important aspect of this is improving the fisheries of the

lake and associated tributaries. One of the most prized fish is the Walleye Pike.

This fish has a migratory nature controlled largely by its feeding spawning

habitats. During the summer walleyes prefer deeper colder water with adequate

food close by and during the spring they migrate upstream to spawn. Most of

what is known about walleye behavior is from lakes and rivers that are very

different than Lake Eau Claire. Lake Eau Claire is a shallow lake with limited

aquatic habitat and deep water zones because of prevailing low oxygen

conditions over most of the period between April and October. There are also

questions regarding Lake Eau Claire walleyes annual spawning success in the

adjoining tributaries. Since the lake was first flooded in 1937 there has been a

consistent loss of what were once ideal spawning conditions. Over the period of

the lake's existence the streams have grown shallower and the once abundant

spawning and nursery areas have declined because of excessive sedimentation.

Over the last 12 years the Lake Eau Claire community in cooperation with

DNR and Eau Claire County has developed and implemented plans to reverse

some of these negative trends on the lake's fisheries. Fish habitat has been

increased by adding fish cribs and tree falls throughout the lake, by dredging the

river and other tributaries to improve fish access, and by opening spawning and

nursery areas previously lost. In 2015 a large area of the lake became habitable

to fish because of the addition of an aeration system that daily circulates large

volumes of oxygen rich water into deep zones that were previously uninhabitable

to fish over most of the year. Each of these changes should improve the overall

habitat for fish in the lake, and it is likely that walleyes because of their preferred

habits will be a major beneficiary.

As a result of these changing conditions of lake fish habitat the study of

walleye behavior became a primary objective for determining the benefits of

what was being done and also to provide guidance for future fish habitat projects.

The project for putting radio tracking devices on individual fish has many potential

informational benefits for walleyes such as

How useful are fish cribs and tree falls in providing new food sources

When and where do they spawn in the tributaries, how many spawn and

how many of those return to the lake

What is the annual survival rate of the fish

Have the fish moved into the deeper now oxygenated waters of the lake

during the summer

Are than any unusual or unexpected behavior patterns that these fish

display

Based on this study are there any suggested changes to future planning

efforts that could improve or protect the lake's fishery." ‐ Rod Zika (Lake Eau

Claire Association member)

Timeline of this Project

During the 2013‐14 school year at Wildlands, a project involving radio

telemetry was attempted by a few students but never got off the ground and

had to be put off until the following year due to time constraints. Coming into

the 2014‐15 school year, this was the biggest item on the agenda and planning

for a radio telemetry project involving Northern Pike started in October of

2014.

After communicating with the Lake Eau Claire Association, a plan was made

to order 10 transmitters to be attached to Walleye instead of Northern Pike.

These 10 transmitters were specially ordered from Advanced Telemetry

Systems Inc to work with the project and were set to be attached to these 10

Walleye. Six of these Walleye were caught and tagged in April of 2015 on the

Eau Claire River which flows into Lake Eau Claire. The remaining two Walleye

were caught and tagged on Lake Eau Claire in May.

Tagging the Walleye

The first step in this process is to figure out where the Walleye are

located. In this case the first Walleye that were tagged were spawning on the

Eau Claire River at County Hwy G Bridge near Augusta, Wi. The following step

is to collect the Walleye in some fashion or another. The process used for this

project was the hook and line method using either live or artificial bait.

Once the Walleye were collected they were put into a small tub filled

with water so that they could still breathe during the tagging process. Before

any Walleye were handled, the team gathered the tools needed to perform

this operation and were fitted with latex gloves to assume no further stress

nor harm was put on the Walleye. The Walleye were then measured and

weighed to ensure that the fish was large enough to handle the added weight

of the transmitter without its natural behavior being affected. Once the

Walleye Passed these credentials, the attaching of the transmitter started.

First the team used 2 very small, hollow metal tubes sharpened on one

end to poke completely through the Walleye just below the dorsal fin. The

cables on the transmitter were then fed through these tubes allowing the

team to then remove the tubes leaving only the cables running through the

Walleye. Then to secure these transmitters on the Walleye, a plastic washer

followed by a metal crimp were threaded onto the cables and secured.

Once this was done the excess cable was snipped off and the fish was

released back where it was collected. The final step is to turn on the

equipment and make sure that the fish can be located.

Walleye Tracking Equipment

All ten of the transmitters for the Lake Eau Claire Walleye Study were

purchased from Advanced Telemetry Systems Inc. Included in this order was

two brand new high tech radio telemetry receivers. All of the equipment for

this project besides the antennas that attach to the receiver was purchased by

the Lake Eau Claire Association and donated to Wildlands School of Science

Research.

Each one of these transmitters is powered by a lithium ion battery and is

equipped with a small section that includes information for the Wildlands

Walleye Team to be contacted if that fish is caught. All of these transmitters

are exactly the same other than that each one emits a different radio

frequency that is picked up by the receivers. These transmitters are also

constantly emitting a pulse so the fish can be found any time throughout the

life of the transmitter which is approximately 880 days.

The effective range that the location of these transmitters can be found

is approximately one mile out of the water. While out on the water the team

has discovered that the pulse can be picked up from about a half mile while

under water.

Method of Tracking the Walleye

Radio telemetry is the most common process used to track an animal and

its movements. Triangulation is the technique used to determine an animal’s

location that has a transmitter on it. When triangulating, a reading is taken

with the antennae finding the general direction of the animal. This gives a cone

shaped direction. Then two more readings are taken from different angles

around the animal and the bisector of all the cones is found. Where these

bisectors intersect is the point of location of that animal.

This method is very difficult to do on a lake with fish due to the fact that

fish move around frequently. Instead, the Wildlands Walleye Team finds the

direction of the fish, then drives the boat towards the fish until the

approximate location (about a 20 foot radius) can be found. This is done by

turning the gain down on the receiver. The gain is a setting on the receiver

that restricts the volume of the pulse that the transmitter puts out.

If the pulse from the transmitter can still be picked up when the gain is all the

way down, the fish is typically within 15 to 20 feet. Smart phones are then

used to plot a point on the ArcGIS map which automatically gets uploaded to

the map on the website.

Aerators on Lake Eau Claire

This year the Lake Eau Claire Association put 15 aerators in various

locations on the west side of Lake Eau Claire. The western side is the deepest

area of the lake and consistently has low DO (dissolved oxygen) levels, making

it poor habitat for fish. These aerators are also effective in stopping and

preventing the growth of blue green algae which can be toxic to humans and

animals.

The Lake Eau Claire Association implemented this huge project that

showed immediate results such as drastically improving the clarity of the

water. Interestingly, since July, most of the walleye have been found near the

aerators. Generally, walleye like deep water and now that they have a place in

the lake that they can actually survive that is deeper than the rest of the lake.

The data suggested to the team that the Walleye will stick around that

area for now until the aerators are turned off. The aerators were turned off in

late October, 2015, due to the changing weather conditions. Once the aerators

were turned off the walleye locations have been very sporadic around the

lake.

ArcGIS and ArcMap

ArcGIS online and ArcMap are the software tools that the Wildlands

Walleye Team uses to present their data. The team is using Arc map version

10.3 which is the latest high tech version of this software. Setting up the

software and doing the tutorials alone took up a lot of the team's time last

year. The data points are automatically updated to the map on the computer

right when the data is entered on a smart phone using the ArcGIS app.

First Half Conclusion of the Lake Eau Claire Walleye Study

The Wildlands Walleye Team will continue to track these fish for the

entirety of the life of the transmitters which is approximately two years. There

will have to be periodic breaks in tracking during the season changes due to

having thin or unstable ice, but tracking will continue once it can be done

safely. As seniors at Wildlands School of Science Research, Dominick Forseth

and Alex Sobotta will be handing down the project to a minimum of two

students that will be attending wildlands for the 2016‐17 school year. These

students will be taught the process of tagging, and tracking these fish so that

they will be able to continue the project. Also being left behind is two

remaining transmitters that may be attached to Walleye either in the summer

of 2016, or once the initial eight transmitters are all dead. The Lake Eau Claire

Association will continue to help these new students in whatever way they can

and continue to improve the project as they did with Dominick and Alex.

Lake Eau Claire

Lake Eau Claire Depth Map

Locations of Fish 503

Location of Fish 522

Location of fish 542


All Fish Locations 2015‐16

seasonal movements of walleye in lake eau claire · seasonal movements of walleye in lake eau...

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