Investigating three sources of bias in hook-and-line surveys: survey design, gear saturation, and multispecies interactions

TitleInvestigating three sources of bias in hook-and-line surveys: survey design, gear saturation, and multispecies interactions
Publication TypeJournal Article
Year of Publication2019
AuthorsKuriyama P.T, Branch T.A, Hicks A.C, Harms J.H, Hamel O.S
JournalCanadian Journal of Fisheries and Aquatic Sciences
Volume76
Pagination192-207
Date Published2019/02
Type of ArticleArticle
ISBN Number0706-652X
Accession NumberWOS:000456966600002
Keywordsbehavior; catch; eurasian perch; Fisheries; growth; Marine & Freshwater Biology; mortality; perca-fluviatilis; performance; size-selectivity; Stock assessment; vermilion snapper
Abstract

Hook-and-line surveys can be used to estimate population trends in fish species where conventional methods such as trawl, acoustic, visual, or pot surveys cannot be applied. Hook-and-line surveys allow for the collection of biological information, but the resultant indices of abundance may be biased. We designed simulations to address concerns around survey design, hook saturation, and competition among species and found that catch per unit effort (CPUE) declined more slowly than population size across all scenarios. This hyperstability was most prominent when fish were found in high-density patches, and these scenarios have median absolute relative error values roughly three to five times greater than those with more even distributions of fish density. Despite hyperstability, the surveys still had statistical power to detect changes in abundance. Interspecific competition for hooks caused bias in survey results when one species was more aggressive than another. Taken together, our results indicate hook-and-line surveys fill a niche in survey methodologies, but their use and interpretation can be challenged by hyperstability and competition among species.

DOI10.1139/cjfas-2017-0286
Short TitleCan. J. Fish. Aquat. Sci.
Student Publication: 
No