Video Camera Sled and ROV
The use of the video camera sled and a remotely operated vehicle (ROV) have been useful in the study of
Tanner crabs in Chiniak Bay.
The newest video camera sled is called the Benthic Resource Assessment Device, model V (BRAD-5).
It carries a digital video camera, 24 V battery, and two 150-W lights. Towed along the seafloor at up to
2 knots, it captures video of crabs and other marine life. Digital video tapes are exchanged after recovery.The sled can be used to cover several miles of
seafloor per day, and search large areas to locate crab aggregations for study. Close-up study is then
conducted using a Phantom ROV.
The BRAD-4 sled sits on the stern deck of the F/V Big Valley prior to leaving the dock (top right photo). An A-frame on the
stern is used to lift and lower the sled into the water. The late skipper Gary Edwards and principle investigator Dr. Brad Stevens (formerly a NMFS scientist)
retrieve the video camera sled aboard the vessel (lower left photo). The lower right photo shows
Brad Stevens inserting the digital video camera into the aluminum housing, developed by Scott McEntire at
the Alaska Fisheries Science Center. The tube has a quartz dome port through which the which the camera looks.
Mark Blakeslee displays the Phantom ROV used for Tanner crab studies. It carries a video camera, lights,
tracking pinger, and sector scanning sonar. The sonar is particularly useful for finding crab aggregations,
and avoiding entanglement with derelict crab pots. Inside the vessel, researchers control the Phantom ROV with joysticks, while viewing the
seafloor, 500 feet below. Additional monitors show the sonar display, tracking display, and location of the ROV.
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