Endogenous versus Exogenous Natural Mortality and Weight in Bioeconomic Models

Rasmus Noss Bang and Stein Ivar Steinshamn

Marine Resource Economics, 2022, vol. 37, issue 4, 491 - 514

Abstract: We present an age-structured multi-fleet model with cannibalism mortality and endogenous weight at age. Using the model and three simplified versions, we show that assumptions of exogenous natural mortality and weight can lead to significant underestimation of optimal fishing mortality in both maximum sustainable yield (MSY) and maximum economic yield (MEY) scenarios for long-lived cannibalistic fish such as the Northeast Arctic cod. In addition, we show that the harvest, spawning stock biomass (SSB), and net present value (NPV) levels associated with optimal exploitation rates increase significantly with assumptions of exogenous natural mortality and weight. The underestimation of optimal fishing mortality, and the corresponding overestimation of SSB and NPV, is more significant in MSY than MEY scenarios. Meanwhile, the overestimation of harvest is more significant in MEY than MSY scenarios. The study also confirms that the Northeast Arctic cod fishery can achieve higher sustainable yield and NPV by changing the fleet composition and target reference points.

Date: 2022
References: Add references at CitEc
Citations:

Downloads: (external link)
http://dx.doi.org/10.1086/721250 (application/pdf)
http://dx.doi.org/10.1086/721250 (text/html)
Access to the online full text or PDF requires a subscription.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:ucp:mresec:doi:10.1086/721250

Access Statistics for this article

More articles in Marine Resource Economics from University of Chicago Press
Bibliographic data for series maintained by Journals Division ().