Abstract
Quantifying whatever harm a Marine Hydrokinetic (MHK) turbine may or may not do to a fish population begins with the probability of an individual encountering the turbine. A definition for probability of a fish encountering a MHK turbine is a precondition for unambiguous calculation from practicable measurements: • Definition: Probability of encounter is the probability that — at some location, during some time interval — a fish that belongs to a distinguishable population will pass through the area that would be swept by the blades of a MHK turbine without the turbine actually being deployed at that position at that time Secondly, any measurement of fish behaviour must recognize the affect of the environment: • Tidal currents are the predominant environmental factor effecting movement of tagged fish and the detection of the acoustic signals that they transmit.