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Teleost fish reaction to light stimulus
depends upon fish physiologic adaptation to ambient light levels prior to
exposure to light level changes. Laboratory studies examining the use of
artificial light to guide juvenile salmon through migration barriers report
measurable differences in fish responses to variations in the quantity and
quality of artificial light.
According to Barbara nightingale and
Charles simenstad, University of Washington, studies in the Pacific Northwest
report potential changes in fish migration behavior and the distribution of
fishes in night-lighted areas. Such changes potentially increase mortality
risks for salmon, herring, and sand lance. Juvenile chum and their predators,
such as hake, dogfish, sculpin, large chinook, and coho, appear to congregate
below night security lights with increased light intensities attracting the
chum and potentially delaying outmigration. The potential changes in species
abundance and dominance resulting from increased prey access under artificial lighting
also warrant further exploration. (Fig.2)
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