Title
The Response of Young Silver Salmon to a Light Barrier After Three Levels of Light Adaptation
Date
1956
Keywords
barriers, constant velocity, flume, flume tests, guidance, illumination, light barriers, salmon, silver salmon, swimming, swimming time
Summary
Sixteen groups of 25 yearling salver salmon (Oncorhynchus kisutch) were tested for guidance in an experimental flume with 2 fps velocity under four combinations of light adaptation and barrier illumination. Five minutes of adaptation to an 8 ft. cdl. level significantly increased the guiding effectiveness of the 8 ft. cdl. light barrier and was accompanied by the longest swimming times in the flume. Adaptation to 100 ft. cdls. destroyed the guiding effectiveness of the 8 ft. cdl. light barrier and greatly reduced the swimming time. Any light in the flume significantly increased the swimming time over that obtained in the dark.