A System-of-Equations Approach to Modeling Age-Structured Fish Populations: The Case of Alaskan Red King Crab, Paralithodes camtschaticus
This paper presents a simultaneous system-of-equations approach to modeling age-structured populations using trawl survey age/size frequency data. The analysis builds upon a Ricker spawner–recruit structure and provides a cohort-based estimation method that retains the underlying dynamic properties...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1991
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Subjects: | |
Online Access: | http://dx.doi.org/10.1139/f91-191 http://www.nrcresearchpress.com/doi/pdf/10.1139/f91-191 |
Summary: | This paper presents a simultaneous system-of-equations approach to modeling age-structured populations using trawl survey age/size frequency data. The analysis builds upon a Ricker spawner–recruit structure and provides a cohort-based estimation method that retains the underlying dynamic properties of a delay-difference model. The framework shares a common spawner–recruit function across age-class equations. This exploits the commonality among cohort members and serves as an instrumental variable, lessening the effect of measurement errors in estimation. The dynamic features of the underlying age-structured population are retained through age-specific net survivability and growth parameters that link age-classes. The technique uses multiple observations on a cohort to further mitigate the effect of measurement error and improve overall estimation efficiency. A seemingly unrelated regression estimation method is required to address contemporaneous correlation of errors across age-classes. This framework is applied to trawl survey data for adult male Alaskan king crab, Paralithodes camtschaticus. |
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