thumbnail

Biology, population structure, and estimated forage requirements of lake trout in Lake Michigan

Technical Paper 111

Out-of-print
By:
and

Links

  • Download citation as: RIS

Abstract

Data collected during successive years (1971-79) of sampling lake trout (Salvelinus namaycush) in Lake Michigan were used to develop statistics on lake trout growth, maturity, and mortality, and to quantify seasonal lake trout food and food availability. These statistics were then combined with data on lake trout year-class strengths and age-specific food conversion efficiencies to compute production and forage fish consumption by lake trout in Lake Michigan during the 1979 growing season (i.e., 15 May-1 December). An estimated standing stock of 1,486 metric tons (t) at the beginning of the growing season produced an estimated 1,129 t of fish flesh during the period. The lake trout consumed an estimated 3,037 t of forage fish, to which alewives (Alosa pseudoharengus) contributed about 71%, rainbow smelt (Osmerus mordax) 18%, and slimy sculpins (Cottus cognatus) 11%. Seasonal changes in bathymetric distributions of lake trout with respect to those of forage fish of a suitable size for prey were major determinants of the size and species compositions of fish in the seasonal diet of lake trout.

Additional Publication Details

Publication type:
Report
Publication Subtype:
Federal Government Series
Title:
Biology, population structure, and estimated forage requirements of lake trout in Lake Michigan
Series title:
Technical Paper
Series number:
111
Year Published:
1983
Language:
English
Publisher:
U.S. Fish and Wildlife Service
Contributing office(s):
Great Lakes Science Center
Description:
18 p.
First page:
0
Last page:
18