期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2017
卷号：114
期号：44
页码：11781-11786
DOI：10.1073/pnas.1703165114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Declines of marine megafauna due to fisheries by-catch are thought to be mitigated by exclusion devices that release nontarget species. However, exclusion devices may instead conceal negative effects associated with by-catch caused by fisheries (i.e., unobserved or discarded by-catch with low postrelease survival or reproduction). We show that the decline of the endangered New Zealand (NZ) sea lion ( Phocarctos hookeri ) is linked to latent levels of by-catch occurring in sub-Antarctic trawl fisheries. Exclusion devices have been used since 2001 but have not slowed or reversed population decline. However, 35% of the variability in NZ sea lion pup production is explained by latent by-catch, and the population would increase without this factor. Our results indicate that exclusion devices can obscure rather than alleviate fishery impacts on marine megafauna.
