Translator Disclaimer
1 August 2016 Growth Model Selection and its Application for Characterizing Life History of a Migratory Bull Trout (Salvelinus confluentus) Population
Author Affiliations +
Abstract

Five growth models were evaluated for their effectiveness in characterizing growth of an isolated population of bull trout, Salvelinus confluentus, undergoing a long term cessation of harvest (1994–2005) in the North Fork Clearwater River, Idaho, above Dworshak Dam. To explore the dynamics of growth in migratory bull trout, one of the models, the von Bertalanffy model, was also fitted based on age estimates derived from annuli and growth increments on pelvic fin ray sections for three juvenile outmigration age groups. Among five growth models evaluated, four models fitted to the age-length data described the fish growth for ages 3 to 11 comparably well. Only a model that exhibited positive growth acceleration as age progressed fitted the data less effectively. Growth was significantly (P < 0.001) related to the age of outmigration from natal streams (1–3 years). Migratory bull trout were found to reach maturation at ages 4–6; the common age-4 maturation was younger than most comparable studies. All mature fish studied reared for 2–3 years in downriver or reservoir habitat. As the adult population size has continued to increase since harvest closure in 1994, further research should be directed towards understanding the trade-offs between these increasing numbers of adult fish and growth, survival, migration, and maturation schedules.

© 2016 by the Northwest Scientific Association. All rights reserved.
John M. Erhardt and Dennis L. Scarnecchia "Growth Model Selection and its Application for Characterizing Life History of a Migratory Bull Trout (Salvelinus confluentus) Population," Northwest Science 90(3), 328-339, (1 August 2016). https://doi.org/10.3955/046.090.0311
Received: 10 January 2015; Accepted: 1 April 2016; Published: 1 August 2016
JOURNAL ARTICLE
12 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top