Translator Disclaimer
1 June 2010 Contribution of Lake Trout Stocked as Fry to an Adult Population in Lake Superior
Mary T. Negus
Author Affiliations +
Abstract

Lake trout Salvelinus namaycush fry treated with heated water to create thermal marks in their otoliths were stocked at Sve's Reef in Minnesota waters of Lake Superior in 1994, 1995, and 1996. These fish began to reach maturity in 2000, and were vulnerable to annual assessment gill nets set at several locations along the Minnesota shoreline. Captured fish also included fin-clipped lake trout stocked as yearlings, and naturally reproduced (wild) lake trout. Otoliths from 3106 undipped lake trout were aged and examined for thermal marks from 2000 to 2007, of which 1152 were from the target year classes (1994–1996). Thermal marks were found in otoliths from 64 fish, or 5.6% of those in the target year classes, demonstrating that stocked fry contributed to the adult lake trout population in Minnesota waters. Although numbers of recaptured fish were too low to demonstrate statistically significant differences, higher recapture rates of marked fish at Sve's Reef in fall and spawning assessments suggest that these fish may have imprinted at the stocking location and homed back to this area to spawn. Wild lake trout populations in Lake Superior may be approaching fully rehabilitated levels, but recovery in the lower Great Lakes has progressed more slowly, and evidence of success with fry stocking could benefit those populations.

Published by Elsevier B.V.
Mary T. Negus "Contribution of Lake Trout Stocked as Fry to an Adult Population in Lake Superior," Journal of Great Lakes Research 36(2), 380-386, (1 June 2010). https://doi.org/10.1016/j.jglr.2009.12.013
Received: 2 March 2009; Accepted: 1 December 2009; Published: 1 June 2010
JOURNAL ARTICLE
7 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

Share
SHARE
KEYWORDS
Fry
imprinting
Lake trout
otolith
stocking
Thermal marking
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top