About
The idea is to fill an artificial lake with fish and then to survey that lake with acoustics, trawling and other methods. Since you know the “true picture” you can study how close you will come with different strategies and efforts. See Why for more details about the usefulness.
The idea came from people at the Great Lakes Science Center in collaboration with researchers from University of Minnesota and Cornell University. The project was started in 2010. Key persons in the project are Jean Adams, Tomas Hrabik, Dan Yule, Dave Warner and Lars Rudstam.
There have been two workshops about the project.
Workshop 1. Sandusky (USA) 27.09 - 01.10. 2010
Title: "Standardization of Great Lakes Acoustic Ground-Truthing Workshop"
Topic: Apportionment methods and survey design in Great lakes pelagic fish assessment
The workshop was held at the Great Lakes Science Center facilities in Sandusky USA
Workshop 2. Stockholm 24-28 October 2011
Title: Assigning ground truth to hydroacoustic density estimates.
Topic: Improving accuracy and precision in fish community assessments.
The workshop was arranged by Swedish University of Agricultural Sciences, Department of Aquatic Resources. Arranging committee was Thomas Axenrot, Ulrika Beier, Malin Hällbom, Erik Petersson, Alfred Sandström. It was held partly at the at the Institute of Freshwater Research, Drottningholm with video conference set up for Lysekil, and partly at Klubbensborg on Mälarhøyden outside Stockholm.
Workshop 3?
Further meetings will most probably be held, but first we need to gain some experience in order to define topics for a further next meeting.
Why would I like to survey a simulated lake?
Much can be learned by surveying an artificial lake with known number of fish.
· Survey design
· Effort allocation
· Evaluation of bias in horizontal integration
· Trawl performance bias (catchability)
· Apportionment methods.
· Gillnet selectivity
How do I survey a simulated lake?
To survey a simulated lake, you will have to patch inn a set of variables in a spreadsheet and in an r-script. There is currently no graphical interface made for this.
2.
Populate the lake with fish
3. Survey the lake
a.
Acoustic
sampling
b.
Midwater
traw sampling
c.
Gil
net sampling (not available yet)
4.
Run
the R script (download R)
5.
Study
the resulting output
Lake templates
A template lake is a simulation project that describes a certain category of water body. The template will typically be a real lake project provided here on voluntarily basis to help others getting started. The idea is that you select the template that fit your situation best, and then modify it. If you end up with a system that differ substantially from the current available templates we will be very happy if you will let it be a new template for others to use in the future. Please contact current editor of this homepage to do so.
Lakes
|
Lake name |
category Oligo/Meso/Aut.. |
Size , Shape, depth |
Species / composition |
Country |
download |
|
Stechlin |
Oligo |
430 ha, mean depth 22,8 m, max depth 69 m |
Vendace/fontaine cisco |
Ge |
Not ready |
|
Rimov |
Meso/eutrophic |
210 ha, mean depth 16m, max depth, 45 m |
Bleak/bream/roach |
Cz |
Not ready |
|
Mälaren, Prästfjärden |
Eutrophic |
101,9/ km2 (basin size) 1120 km2 (lake size), mean depth 14 m, max depth 66 m |
Smelt/vendace/pikeperch |
Se |
Not ready |
|
Randsfjorden |
Oligo |
138 km2, max depth 120 m |
Smelt/whitefish |
No |
Not ready |
Acknowledgement
Workshop 1
Funding for the first workshop was provided by the Great Lakes Fisheries Commission
and the USGS Great Lakes Science Center with additional support from collaborating
agencies and universities around the North American Great Lakes.
Workshop 2
The workshop was financed by the project MISS, a project funded by a variety of Swedish
national and regional authorities: Swedish Enironmental Protection Agency, Swedish Board
of Fisheries (currently under the new name Havs- och Vattenmyndigheten), County Administration
Boards around Lake Mälaren (Stockholm and Västmanland), Mälarens vattenvårdsförbund and
Vattenmyndigheten Norra Östersjön.
Contact
Current
editor
Current editor of this home page is
Helge Balk
University of Oslo,
Department of Physics
http://folk.uio.no/hbalk/