Rockfishes have closed swim bladders that prevent rapid gas expulsion, making them susceptible to barotrauma when captured. Although descending devices are now required for releasing non-retainable rockfishes in British Columbia and some United States jurisdictions, long-term post-release survival varies by species and remains understudied. We conducted a mark-recapture study around a small island in the Strait of Georgia in 2020–2021. Using field data from 352 tagged rockfishes across nine species, we quantified external barotrauma symptoms and identified species-specific and depth-related patterns. We documented some cases of immediate external barotrauma reversal (tight abdomen and pop-eye), limited behavioural impairment upon release, and no depredation. Two recaptured individuals (0.6%; 2/352) confirmed post-release survival (28–132 days). The low recapture rate may reflect migration from the study area among other potential factors. While SeaQualizers effectively returned rockfishes to depth in many cases and represents an improvement over surface release, we documented notable challenges with fish resurfacing and inaccurate release depths. These findings warrant communication to anglers and managers.
Davies et al. (Thu,) studied this question.
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