Numbers of sauger Stizostedion canadense declined in the Peoria
Pool of the Illinois River from the 1970s to the 1990s. Stocking
was evaluated as a means of supplementing natural reproduction
in the pool. Marked fry were stocked in 1991–1994 (20–176/ha),
and marked fingerlings were stocked in 1990–1995 (,1–20/ha). In
1990, fingerlings with a mean total length of 44 mm were stocked
in June, and 92-mm fingerlings were stocked in September and
October. Relative survival was 4.9:1 in favor of the 44-mm
fingerlings. During 1991–1994, relative survival averaged 440:1
for stocked fingerlings (39–61 mm) versus fry. From 1990 to
1995, contribution of stocked saugers to the year-classes
averaged 33.9% at age 0. Because of the immigration of wild
saugers into Peoria Pool and emigration of stocked and wild fish
to other pools, contributions of stocked saugers to individual
year-classes decreased each year subsequent to stocking. Mean
contribution of stocked saugers at harvestable ages (age 2 and
older) was 9.1%. Total co