Upload
greenlakeassociation
View
3.024
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Big Green Lake underwent a comprehensive fish survey beginning in spring 2011. At the 2011 GLA Annual Meeting, guest presenter Dave Bartz, WI DNR Fisheries Biologist, shared sampling techniques for collecting data on different fish species and also shared what information he hopes to gather during the survey.
Citation preview
Big Green Lake Fish Survey - 2011
ObjectivesObjectives Sample Coolwater FisheriesSample Coolwater Fisheries
Spring Fyke netting and ElectrofishingSpring Fyke netting and Electrofishing Walleye, Northern Pike, Bass sp. and panfishWalleye, Northern Pike, Bass sp. and panfish
Catch Rates/Population DensityCatch Rates/Population Density Population Age Structure and Growth RatesPopulation Age Structure and Growth Rates
Fall ElectrofishingFall Electrofishing Walleye RecruitmentWalleye Recruitment
Sample Coldwater FisheriesSample Coldwater Fisheries Fall Gill Netting, Fyke Netting and ShockingFall Gill Netting, Fyke Netting and Shocking
Lake Trout, Brown Trout and Cisco Lake Trout, Brown Trout and Cisco Catch Rates/Population Density Catch Rates/Population Density
Carp?Carp?
Fyke Net Lead
Set Fyke Net
Set Net ready to run
Sex determination on Northern Pike
All fish sexed and measured to nearest tenth of an inch Weights and age samples taken on subsample
Green Lake Musky
2500 stocked annually since 2004
Black Crappie
Walleye Length Frequency
0
20
40
60
80
100
120
140
160
180
12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
Inch Class
Num
ber
Males
Females
Walleye Length - Percent Frequency
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
Inch Class
Perc
ent
Males
Females
Northern Pike Length Frequency
0
5
10
15
20
25
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Inch Class
Num
ber
males
females
Northern Pike Length - Percent Frequency
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Inch Class
Perc
ent
males
Females
Boomshocker
Age StructuresAge StructuresDorsal Spines
Scales
Walleye - 94 surveyWalleye - 94 survey
Low density populationLow density population Recruitment problemsRecruitment problems
habitat losshabitat loss predation/competitionpredation/competition cool water temperaturescool water temperatures
Increased interest in stockingIncreased interest in stocking Concern over geneticsConcern over genetics
Mixing OTC Solution for marking fry
Gill NettingGill Netting
Net locations are historical sitesNet locations are historical sites Target species are Lake Trout and Target species are Lake Trout and
CiscoCisco Catch rate comparisonsCatch rate comparisons Size structure comparisonsSize structure comparisons New aging techniques New aging techniques
Stocking 1980-PresentStocking 1980-Present
Quotas increased 1980-82Quotas increased 1980-82 Increased recruitment by 1984Increased recruitment by 1984 Disease problems 1987-89 - No stockingDisease problems 1987-89 - No stocking Stocking quotas raised to 50,000 in 1991Stocking quotas raised to 50,000 in 1991 Presently quotas back to 25,000Presently quotas back to 25,000 Average 30,736 since 1992Average 30,736 since 1992 VHS concerns have affected availabilityVHS concerns have affected availability
Cisco
Seeforellen Brown Trout
CarpCarp
First planted in 1882First planted in 1882 Full scale removal efforts by 1930’sFull scale removal efforts by 1930’s Carp trap at County A in 1950’s-60’sCarp trap at County A in 1950’s-60’s State rough fish crews 1950’s-60’sState rough fish crews 1950’s-60’s Commercial removal during the 80’sCommercial removal during the 80’s Carp trap at County K – 1992 Carp trap at County K – 1992
replaced by barrier in 2009replaced by barrier in 2009 Commercial contractsCommercial contracts
SummarySummary
Fish Populations are constantly Fish Populations are constantly changingchanging
What can be done to help improve?What can be done to help improve? Habitat Protection and RestorationHabitat Protection and Restoration Water Quality IssuesWater Quality Issues Aquatic InvasivesAquatic Invasives
PlantsPlants AnimalsAnimals Disease - VHS?Disease - VHS?
Goal is to Improve Fish Populations and Fishing
Thank YouThank You
Questions ?