Acoustic Assessment of Fish Presence and Vertical Distribution at the FORCE Tidal Turbine Test Site in Minas Passage, Bay of Fundy

Haley Viehman and Anna Redden

Haley Viehman and Anna Redden, Acadia University

The effects on fish of large tidal in-stream energy conversion (TISEC) devices deployed in very high flow environments (>2 m/s) are generally unknown. To better understand fish use of the FORCE test site and their potential for interaction with TISEC devices, we used an ASL Acoustic Zooplankton and Fish Profiler (AZFP), housed on a FORCE sensor platform, to examine how fish density and vertical distribution varied with respect to tidal stage and time of day, and how these factors influence potential spatial overlap of fish with a TISEC device (Cape Sharp Tidal / OpenHydro design – 16 m diameter).  This webinar will highlight AZFP data collected from sensor platform deployments in December 2015 – January 2016 and June – July 2016, prior to the testing of a cabled CST/OH turbine in November 2016.

We observed higher densities of fish at the FORCE site during the flood tide than the ebb.  Observed vertical distributions of fish were used to estimate the probability that fish within the passage cross-section might spatially overlap with (and therefore potentially encounter) a TISEC device. Although spatial overlap probabilities for a single CST/OH turbine were very low, further work is needed to assess fish encounter and avoidance probabilities for single TISEC devices and arrays.