NEW THIS YEAR! The schedule of technical sessions is in Sched.org which allows you to search within the schedule, filter the schedule to show sessions only occurring on a certain date, within a track, or in a room. You can also build your own schedule by creating a free account in Sched.org. Click here to return to the main Midwest Fish & Wildlife Conference website. 

PLEASE NOTE: The schedule posted here is as of 1/25/16, and is subject to change. Please check back for updates.
Back To Schedule
Tuesday, January 26 • 1:40pm - 2:00pm
Prey Fish Age Estimation To Inform Sport Fishery Management: An Application To Lake Michigan Alewife

Sign up or log in to save this to your schedule, view media, leave feedback and see who's attending!

AUTHORS: David Warner, USGS Great Lakes Science Center; Randall Claramunt, Michigan Department of Natural Resources Charlevoix Fisheries Research Station; Timothy O'Brien, USGS Great Lakes Science Center; Charles Madenjian, USGS Great Lakes Science Center; Bo Bunnell, USGS Great Lakes Science Center

ABSTRACT: Alewife have been an important species in the Lake Michigan fish community since their invasion and subsequent proliferation to extremely high abundance during the 1960s. Exceedingly high biomass of alewife coupled with a predator poor ecosystem led to the introduction of Pacific salmonines, chiefly Chinook salmon, for which management is tightly linked to alewife abundance. The USGS Great Lakes Science Center (GLSC) has measured alewife abundance and biomass annually through fish community assessments using bottom trawls, acoustics, and midwater trawls. Alewife age estimation is also part of annual population assessments – scales were used originally, but since 1984 sagittal otoliths have been used determine age structure of the population. Earlier studies used age composition data on alewife populations to describe growth and aid in the understanding of recruitment processes. Additionally, age composition data are now used to index predation pressure (number of age classes present), to develop age-specific estimates of alewife biomass, and to forecast future biomass from stock assessment biomass estimates. In this paper, we review the alewife aging program currently in use on Lake Michigan and provide an overview of how age data and age-specific biomass estimates of alewife are used in the management of a socially and economically important sport fishery for Chinook salmon.

Tuesday January 26, 2016 1:40pm - 2:00pm EST
Emerald A