DIDSON moves through electric barrier. The DIDSON boat travels upstream through the electric barrier for the caged fish study. The cage containing the fish is mounted to the side closest to the wall. One person operates the DIDSON and views the fish on the computer screen, while a caller calls out the boats position using the orange numbers on the wall. The computer operator records the time that the number is called and the fish’s behavior at that time. Photo

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Size: 1632px × 1224px
Photo credit: © Natural History Collection / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: animal, animals, archive, barrier, carterville, conservation, conserve, education, electric, fauna, fish, fishing, flora, fwco, habitat, history, image, learning, management, midwest, natural, nature, office, photo, preservation, preserve, record, reference, refuge, service, states, united, usfws, wildlife, world