TY - RPRT
TI - Use of Fish Tracking Data to Model Striped Bass Turbine Encounter Probability in Minas Passage
AU - Redden, A
AU - Sanderson, B
AB - This project utilized fish tracking datasets and Vemco detection-range tests to calculate fish-turbine encounter probabilities for striped bass. Detection-range tests enables the probability of detecting a transmitted signal to be empirically determined as a function of range, transmitter source level, and current speed. Detections of tagged striped bass by receivers at the FORCE test site can be considered as an indication of how likely tagged striped bass are to be found in the vicinity where turbines are expected to be installed. The probability of detection enables calculation of the effective area surrounding a receiver that a transmission from a tagged fish is expected to be detected. Having calculated effective area and having measured detections of tagged striped bass, it is then possible to calculate abundance of tagged striped bass and thus the number that might encounter a hypothetical tidal turbine as they are swept along by the current over some time interval. Roughly speaking, detections by receivers are a proxy for encounters with turbines.Tagged striped bass were determined to be of local Bay of Fundy origin, based on genetic analysis of 294 fin clip samples. The probability that a tagged striped bass encounters a turbine is, therefore, representative of encounters by the local population. The local population of striped bass has been estimated to be 15000. This number enables encounters by tagged striped bass to be converted into encounters by striped bass of the local population.Presently we define encounter as the number of striped bass swept past a 16 m wide line at a position occupied by a hypothetical turbine that spans from top to bottom of the water column. This represents an overestimate that could be refined if the depth distributions of fish and turbine are specified. Different detection-range experiments give somewhat different values for probability of detection and the number of encounters is inversely related to. For example, during the month of July 2011 it was estimated that there would be 86 encounters at the FORCE site based on a detection-range test at the FORCE site but 233 encounters based on a detection-range test at the MPS receiver line.Present estimates of monthly number of encounter do not represent the number of striped bass that would be harmed by a turbine. Many fish might pass either above or below the turbine. Some fish might avoid the turbine by swimming around it. Others might pass through the area swept by the turbine but still evade the blades. There is much uncertainty in the numbers calculated which can only be resolved by making further detection-range measurements.
CY - Wolfville, Nova Scotia, Canada
DA - 2016/09//
PY - 2016
SP - 55
PB - Acadia University
SN - ACER Technical Report No. 122
LA - English
KW - Marine Energy
KW - Collision
KW - Fish
ER -