Predicting paddlefish roe yields using an extension of the Beverton–Holt equilibrium yield-per-recruit model

North American Journal of Fisheries Management
By: , and 

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Abstract

Equilibrium yield models predict the total biomass removed from an exploited stock; however, traditional yield models must be modified to simulate roe yields because a linear relationship between age (or length) and mature ovary weight does not typically exist. We extended the traditional Beverton-Holt equilibrium yield model to predict roe yields of Paddlefish Polyodon spathula in Kentucky Lake, Tennessee-Kentucky, as a function of varying conditional fishing mortality rates (10-70%), conditional natural mortality rates (cm; 9% and 18%), and four minimum size limits ranging from 864 to 1,016mm eye-to-fork length. These results were then compared to a biomass-based yield assessment. Analysis of roe yields indicated the potential for growth overfishing at lower exploitation rates and smaller minimum length limits than were suggested by the biomass-based assessment. Patterns of biomass and roe yields in relation to exploitation rates were similar regardless of the simulated value of cm, thus indicating that the results were insensitive to changes in cm. Our results also suggested that higher minimum length limits would increase roe yield and reduce the potential for growth overfishing and recruitment overfishing at the simulated cm values. Biomass-based equilibrium yield assessments are commonly used to assess the effects of harvest on other caviar-based fisheries; however, our analysis demonstrates that such assessments likely underestimate the probability and severity of growth overfishing when roe is targeted. Therefore, equilibrium roe yield-per-recruit models should also be considered to guide the management process for caviar-producing fish species.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Predicting paddlefish roe yields using an extension of the Beverton–Holt equilibrium yield-per-recruit model
Series title North American Journal of Fisheries Management
DOI 10.1080/02755947.2013.820242
Volume 33
Issue 5
Year Published 2013
Language English
Publisher American Fisheries Society
Publisher location Lawrence, KS
Contributing office(s) Coop Res Unit Atlanta
Description 10 p.
First page 940
Last page 949
Online Only (Y/N) N
Additional Online Files (Y/N) N