Sonar estimates of daytime activity levels of Euphausia pacifica in Saanich Inlet

  title={Sonar estimates of daytime activity levels of Euphausia pacifica in Saanich Inlet},
  author={Jules S. Jaffe and Mark D. Ohman and Alex De Robertis},
  journal={Canadian Journal of Fisheries and Aquatic Sciences},
A three-dimensional multibeam tracking sonar system (FishTV) was deployed in the stratified waters of Saanich Inlet in July-August of 1996 and 1997 to assess the swimming behavior of euphausiids in situ. Here, a new algorithm is used to estimate swimming velocities of animals from the uncorrelated displacements of acoustic targets in pairs of sonar frames with increasing time delays between frames. Assuming isotropic motions of euphausiids, the superior spatial resolution of the sonar in one… 

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