Biomanipulation du meunier noir (Catostomus commersoni)

3.1 ABSTRACT
The goal of this study was to quantify white sucker and brook trout responses to 6-
9 yr of white sucker mass removal in three lakes and to the cessation of this
biomanipulation in two of these lakes. There was a general decrease in the abundance
and biomass of white sucker, a general increase in the abundance and biomass of brook
trout, an increase in the recruitment and growth of white sucker and brook trout, and a
decrease in the age at maturity of both species during mass removal. After the end of
white sucker removal, the recruitment increased in white sucker and decreased in brook
trout, and the growth and age at maturity of both species decreased. Brook trout females
produced a larger number of eggs but of smaller size during mass removal and the
reverse occurred after the cessation of white sucker mass removal. This study, based on
a gradient ofmass removal in time and intensity, enabled us to test the effects of intra­
and interspecific competition on the life-history traits ofboth species.
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