Fisheries Techniques, 3rd Edition Chapters 6 &...
Transcript of Fisheries Techniques, 3rd Edition Chapters 6 &...
![Page 1: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/1.jpg)
Fisheries Techniques, 3rd Edition
Chapters 6 & 7
![Page 2: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/2.jpg)
Outline Today
Goals – Fish sampling gear (2 lectures)
1) Electrofishing
2) Passive and active gear
Accompanying lab: Thursday Sep 28
![Page 3: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/3.jpg)
Capture Gear in Fisheries (& WL)
![Page 4: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/4.jpg)
Which is the ‘active’ method?A. …we’ll eat like kings
B. …keep the lights in their eyes and you can bag them
![Page 5: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/5.jpg)
Passive Techniques—Advantages
![Page 6: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/6.jpg)
Passive Techniques—Disadvantages
![Page 7: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/7.jpg)
Float Line
Lead Line
Entanglement
![Page 8: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/8.jpg)
Gill nets
Trammel netsFloat Line
Lead Line
Entanglement
![Page 9: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/9.jpg)
Problems with gill nets and trammel nets
![Page 10: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/10.jpg)
Figure 7.2 – Mesh
Factors influencing
Gill Net CPUE
![Page 11: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/11.jpg)
Passive Angling gears
![Page 12: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/12.jpg)
SOPs
![Page 13: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/13.jpg)
Mouth
Cod endLotic
Lentic
“wing or lead net”
Entrapment
![Page 14: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/14.jpg)
Light traps Larval fish
![Page 15: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/15.jpg)
Pot Gears
![Page 16: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/16.jpg)
Active Advantages
Disadvantages
Electrofishing
Angling
Seining
Throw and cast nets
Toxicants?
![Page 17: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/17.jpg)
TrawlsMouth
Cod end
![Page 18: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/18.jpg)
Bottom Trawls
![Page 19: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/19.jpg)
Midwater Trawls
![Page 20: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/20.jpg)
Dredges
![Page 21: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/21.jpg)
Encircling Nets
Nemo’s last scare
Float Line
Lead Line
![Page 22: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/22.jpg)
OthersCast net
Gig
![Page 23: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/23.jpg)
OthersCast net
Gig
![Page 24: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/24.jpg)
Data and data analysis
Fisheries stock assessments
![Page 25: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/25.jpg)
Data Relative abundance
Size structure
Growth
Mortality
Recruitment
Collecting specimens
Accessory data: diet, age (scales)
![Page 26: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/26.jpg)
CPUE INDEX of density
Index of density trends
CPUE
Den
sity
![Page 27: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/27.jpg)
Assumed pattern of CPUE vs. Density
A. Inversely proportional
B. Directly proportional
C. Exponential
D. Flat line (no slope)
CPUE
Den
sity
![Page 28: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/28.jpg)
CPUE INDEX of density
Index of density trends
What else can affect relationship?CPUE
Den
sity
BOX 6.4
Techniques Book
![Page 29: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/29.jpg)
CPUE Best solution:
rigid sampling protocol from time 1 to time x
![Page 30: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/30.jpg)
Factors affecting gear choice
Things to consider
Usually want to be quantitative
And Representative
![Page 31: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/31.jpg)
Factors influencing gear choice
All gear is selective Good – for business
Bad – for science
Results in…
…Bias—unknown shift from truth So standardize to detect changes
![Page 32: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/32.jpg)
Factors influencing gear choice
Fish size / species
“Recruitment to the gear”
Pond fyke nets catch crappies not bass?
![Page 33: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/33.jpg)
Factors influencing gear choice Environmental influences
Weather
Habitat – e.g., tree stumps and seining
Flow / turbidity
Crew experience
Equipment type and crew experience interaction
![Page 34: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/34.jpg)
Animal behavior Know their biology/ecology
Recruitment to the gear
![Page 35: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/35.jpg)
Factors influencing gear choice OBJECTIVES
INFERENCE
CONSISTENCY
Choose your gear properly
Defend your methods
![Page 36: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/36.jpg)
Decision Tree
for ACTIVE
Gear Choice
Figure 7.8
Does NOT
substitute for
your thinking !
![Page 37: Fisheries Techniques, 3rd Edition Chapters 6 & 7jcsites.juniata.edu/faculty/merovich/ESS445_files/Active_Passive... · Fisheries Techniques,3rd Edition Chapters 6 & 7. Outline Today](https://reader036.fdocuments.us/reader036/viewer/2022062303/6109d97f328048184056312a/html5/thumbnails/37.jpg)
y = 2.11x - 14167
R2 = 0.8795
y = 1.58x - 10625
R2 = 0.8795
6000
8000
10000
12000
14000
16000
18000
6000 8000 10000 12000 14000 16000 18000
Acoustic Abundance
Ro
ten
on
e A
bu
nd
an
ce
1 day
3 day
Verification