Wigley S, Blaylock J, Rago P 2009 River herring discard estimation, precision and sample size analysis Northeast Fish Sci Cent Ref Doc 09-20; 15 p https://repository.library.noaa.gov/view/noaa/3690 Wigley Susan E Blaylock Jessica Rago Paul J Division Resource Evaluation & Assessment READ Population Dynamics Secondary NEFSC Ref or Lab Document Reports