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DIDSON Sonar Videos
Dave Ray Didson1

   Picture of the U.S. Fish and Wildlife Service conducting an exploratory study of the nearshore distribution of Bering cisco during their spawning run upstream into the Yukon Flats. Here's a picture of the DIDSON imaging sonar being deployed below the Rapids video test wheel. Preliminary results suggest that the cisco are swimming very close to shore (mostly within 12 feet) in the fast river currents at Rapids. Dave Daum and Ray Hander are the research biologists on site. Dip nets were used to confirm the presence of Bering cisco passing in front of the sonar transducer. Any questions can be sent to

  Check These Chum Salmon Pinball Videos Out

 And here’s some really interesting DIDSON video clips that have biologists and researchers that have seen them scratching their heads. If I told you DIDSON Sonar shows that the migrating fish that travel up the Yukon in the silty water bump into rocks etc. rather regularly, I would expect you to not believe me and think I was interpreting to much into the sonar image. That is until you looked at one of these videos below. Click on to open

Chum Salmon Hitting Rock #1 (3 MB)

Chum Salmon Hitting Rock #2 (2 MB)

Burbot Hunting in Sonar Beam (6 MB)




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