Robert P. Mueller, Richard S. Brown, Haakon Hop, and Larry Moulton
(2006): Video and acoustic camera techniques for studying fish under
ice: a review and comparison. Rev. Fish Biol. Fisher., Vol 16 (2),
213-226.
Abstract: Researchers attempting to study the presence, abundance,
size, and behavior of fish species in northern and arctic climates
during winter face many challenges, including the presence of thick
ice cover, snow cover, and, sometimes, extremely low
temperatures. This paper describes and compares the use of video and
acoustic cameras for determining fish presence and behavior in lakes,
rivers, and streams with ice cover. Methods are provided for
determining fish density and size, identifying species, and measuring
swimming speed and successful applications of previous surveys of fish
under the ice are described. These include drilling ice holes,
selecting batteries and generators, deploying pan and tilt cameras,
and using paired colored lasers to determine fish size and habitat
associations. We also discuss use of infrared and white light to
enhance image-capturing capabilities, deployment of digital recording
systems and time-lapse techniques, and the use of imaging
software. Data are presented from initial surveys with video and
acoustic cameras in the Sagavanirktok River Delta, Alaska, during late
winter 2004. These surveys represent the first known successful
application of a dual-frequency identification sonar (DIDSONTM)
acoustic camera under the ice that achieved fish detection and sizing
at camera ranges up to 16 m. Feasibility tests of video and acoustic
cameras for determining fish size and density at various turbidity
levels are also presented. Comparisons are made of the different
techniques in terms of suitability for achieving various fisheries
research objectives. This information is intended to assist
researchers in choosing the equipment that best meets their study
needs.
DOI 10.1007/s11160-006-9011-0
Regards
Sonja Amoser
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University of Vienna, Dept. of Neuroscience and Behavioral Biology
Sonja Amoser
PhD Student, Research Associate
Althanstrasse 14
1090 Vienna
Austria
tel: +43 (1) 4277 54467
fax: +43 (1) 4277 54506
mobile: +43 (664) 500 61 06
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