Fisheries Behavioral Ecology - Abstracts
Spencer, M.L., A.W. Stoner, C.H. Ryer, and J.E. Munk. 2005. A towed camera sled for estimating abundance of juvenile
flatfishes and habitat characteristics: Comparison
with beam trawls and divers. Estuarine, Coastal and Shelf Science 64:497-503.
Abstract
An inexpensive towed video camera sled was developed to provide abundance estimates for juvenile flatfishes and other benthic taxa, and to characterize habitat features. The camera sled was compared with beam trawls and diver survey methods in Yaquina Bay, Oregon, and in bays of Kodiak Island, Alaska. In Yaquina Bay the camera sled with a tickler chain (to induce flatfish
movement) yielded density estimates for juvenile flatfish (English sole, Pleuronectes vetulus) that were equivalent to those of the
divers, but greater than with a 1 m beam trawl or the camera sled without a tickler chain. Crab (Cancer magister) density estimates
were similar between the divers and the camera sled (with or without the tickler chain), but were underestimated with the beam
trawl. In Kodiak, densities of juvenile flatfish (northern rock sole, Lepidopsetta polyxystra) were similar between the camera sled
with a tickler chain, divers, and a 2 m beam trawl. Density estimates from the camera sled were obtainable for flatfish as small as 20
mm. Habitat features, such as empty bivalve shells, were underestimated with the beam trawl compared with the divers and the
camera sled. These results demonstrate the effectiveness of an inexpensive, simple to operate, towed camera sled in surveying
abundance and habitat associations of juvenile flatfishes, crabs, and other taxa.
Last updated
26 April, 2007
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