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Table 1 The four specific criteria were adopted to establish the data quality objectives for the project

From: An approach for filtering hyperbolically positioned underwater acoustic telemetry data with position precision estimates

  Objective Criteria Rationale
1 Detect changes in trajectory Mean error ≤1.77 m Many trajectory based analyses are only preserved when the average position error is <10% of the mean step length [17]. Transmission delay was (33.4 s), sea lamprey ground speed is 0.53 ms-1 [18, 19], equating to a step length of 17.7 m.
2 Assign behavioral state (moving or stationary) to fish positions Max error <15 m Simple behavioral assignment of moving or stationary with first passage time analysis, which is a measure of the time it takes an individual to leave a circle of fixed radius r drawn around each measured location to determine if movement is occurring [20, 21]. Based on prior analyses, a displacement of greater than 15 m per transmission at the average tag transmission rate (33.4 s) could result in a false designation of moving when the fish was stationary.
3 Assign habitat to fish positions 2DRMS ≤6 m To ensure accurate assignment of each estimated fish position to habitat types that are defined at the resolution of 18 × 18 m grid cells we selected a twice the distance root mean square (2DRMS) error of <6 m for our selected HPE values.
4 Balance loss of acceptable data and retention of unacceptable data Retain 95% of acceptable data, Reject ≥99% of unacceptable data To ensure accurate assignment of each estimated fish position to habitat types while avoiding loss of accurate data. We aimed to keep 95% of acceptable data (≤6 m) while retaining <1% of unacceptable data (>6 m) of all retained positions (unacceptable data remaining/all retained positions × 100).