Estimating reef fish discard mortality using surface and bottom tagging: effects of hook injury and barotrauma

Canadian Journal of Fisheries and Aquatic Sciences
By: , and 

Links

Abstract

We estimated survival rates of discarded black sea bass (Centropristis striata) in various release conditions using tag–recapture data. Fish were captured with traps and hook and line from waters 29–34 m deep off coastal North Carolina, USA, marked with internal anchor tags, and observed for release condition. Fish tagged on the bottom using SCUBA served as a control group. Relative return rates for trap-caught fish released at the surface versus bottom provided an estimated survival rate of 0.87 (95% credible interval 0.67–1.18) for surface-released fish. Adjusted for results from the underwater tagging experiment, fish with evidence of external barotrauma had a median survival rate of 0.91 (0.69–1.26) compared with 0.36 (0.17–0.67) for fish with hook trauma and 0.16 (0.08–0.30) for floating or presumably dead fish. Applying these condition-specific estimates of survival to non-tagging fishery data, we estimated a discard survival rate of 0.81 (0.62–1.11) for 11 hook and line data sets from waters 20–35 m deep and 0.86 (0.67–1.17) for 10 trap data sets from waters 11–29 m deep. The tag-return approach using a control group with no fishery-associated trauma represents a method to accurately estimate absolute discard survival of physoclistous reef species.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Estimating reef fish discard mortality using surface and bottom tagging: effects of hook injury and barotrauma
Series title Canadian Journal of Fisheries and Aquatic Sciences
DOI 10.1139/cjfas-2013-0337
Volume 71
Issue 4
Year Published 2013
Language English
Publisher NRC Research Press
Contributing office(s) Coop Res Unit Atlanta
Description 7 p.
First page 514
Last page 520
Country United States
State North Carolina
Other Geospatial Onslow Bay
Online Only (Y/N) N
Additional Online Files (Y/N) N