Are flow scale and observer scale relationships the same among North Pacific at-sea processors?

Fishery observers in the North Pacific serve a dual role as scientific samplers and compliance monitors. While this latter role is complex because it can cause conflict with the industry, it serves an important role in maintaining data integrity and helps deter and prevent seafood harvesting fraud. Concerns over the potential for intentional tampering with scales used to weigh catch on some at-sea processing vessels led the Alaska Fisheries Science Center’s Fishery Monitoring and Analysis Division (FMA) to collect numerous sample weights from both onboard observer scales and industry scales in the hopes that these would be useful to law enforcement. Comparison of these data were made using a mixed model to account for as many confounding effects as possible and isolate between-vessel effects measured over 5 years. Current data quality control protocols and attention resulted in a data set that was more variable than the effect size to be detected, even after removal of extreme outliers. Consequently, the data are not useful for identifying differences in scale congruence between vessels measured annually without serious data manipulation by analysts --a process which could potentially negate the utility of the results for the National Oceanic and Atmospheric Administration’s Fisheries Office of Law Enforcement (OLE). However, the data may be useful for identifying changes in between-scale agreement within a vessel during a time series for further investigation by OLE. 2020 NMFS (National Marine Fisheries Service) AFSC (Alaska Fisheries Science Center) Submitted https://doi.org/10.25923/z29q-bj69 Public Domain 1930