Performance of pop-up satellite archival tags

ABSTRACT: Pop-up satellite archival tags (PSATs) are used to chronicle or ‘archive’ the habitat preferences, horizontal and vertical movements, fishery interaction, and post-release mortality rates of a variety of pelagic animals. Though PSATs are valuable research tools, lower-than-expected reporting rates, early detachment, and incomplete data return remain problematic. These issues were quantified by analysis of reporting rates, retention times (i.e. the time period PSATs remained attached), and the quantity of depth, temperature, and geolocation data returned from 731 PSAT deployments on 19 species in the authors’ database and 1433 PSAT deployments on 24 species taken from 53 published articles. The reporting rate of PSATs deployed by the authors (0.79, 95% CI = 0.76 to 0.82) was not significantly different from the reporting rate calculated from published studies (0.76, 95% CI = 0.74 to 0.78). PSAT reporting rates were lowest in species undertaking large (~1000 m) vertical excursions (logistic regression, p = 0.006), and reporting rates have increased significantly over time (p = 0.02), presumably because of better PSAT design and construction. Tag retention increased with depth range of the tagged species and pop-off latitude (Cox proportional hazards models, p < 0.001), suggesting that pressure (and/or temperature), biofouling, and wound infection at the insertion site of the PSAT’s anchoring device influenced this parameter. The quantity of data returned by Argos satellites was affected by tag production year, programmed pop-up period, depth range, and manufacturer. Species-specific reporting rates were used to make recommendations for future PSAT sampling designs.