Measurement errors in body size of sea scallops (Placopecten magellanicus) and their effect on stock assessment models

Jacobson, Larry D. and Stokesbury, Kevin D. E. and Allard, Melissa A. and Chute, Antonie and Harris, Bradley P. and Hart, Deborah and Jaffarian, Tom and Marino II, Michael C. and Nogueira, Jacob I. and Rago, Paul (2010) Measurement errors in body size of sea scallops (Placopecten magellanicus) and their effect on stock assessment models. Fishery Bulletin, 108(2), pp. 233-247.

[img]
Preview
PDF (The document's language is English .) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (890Kb) | Preview
Official URL: http://fishbull.noaa.gov/1082/jacobson.pdf

Abstract

Body-size measurement errors are usually ignored in stock assessments, but may be important when body-size data (e.g., from visual sur veys) are imprecise. We used experiments and models to quantify measurement errors and their effects on assessment models for sea scallops (Placopecten magellanicus). Errors in size data obscured modes from strong year classes and increased frequency and size of the largest and smallest sizes, potentially biasing growth, mortality, and biomass estimates. Modeling techniques for errors in age data proved useful for errors in size data. In terms of a goodness of model fit to the assessment data, it was more important to accommodate variance than bias. Models that accommodated size errors fitted size data substantially better. We recommend experimental quantification of errors along with a modeling approach that accommodates measurement errors because a direct algebraic approach was not robust and because error parameters were diff icult to estimate in our assessment model. The importance of measurement errors depends on many factors and should be evaluated on a case by case basis.

Item Type: Article
Title: Measurement errors in body size of sea scallops (Placopecten magellanicus) and their effect on stock assessment models
Personal Creator/Author:
CreatorsEmail
Jacobson, Larry D.
Stokesbury, Kevin D. E.
Allard, Melissa A.
Chute, Antonie
Harris, Bradley P.
Hart, Deborah
Jaffarian, Tom
Marino II, Michael C.
Nogueira, Jacob I.
Rago, Paul
Refereed: Yes
Journal or Publication Title: Fishery Bulletin
Volume: 108
Number: 2
Page Range: pp. 233-247
Date: 2010
ISSN: 0090-0656
Issuing Agency: United States National Marine Fisheries Service
Subjects: Biology
Ecology
Fisheries
Item ID: 8761
Depositing User: Patti M. Marraro
Date Deposited: 11 Jun 2012 18:32
Last Modified: 11 Jun 2012 18:32
URI: http://aquaticcommons.org/id/eprint/8761

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...