Four members of the Lake Ontario Management Unit were at Corbett’s dam in Port Hope on Friday. The members were measuring the length, weight, checking for lamprey marks and taking scale samples of rainbow trout in their annual rainbow trout assessment in the Ganaraska River.. The largest fish this year has been approximately 14 pounds, while on Friday the largest was just over 12 pounds. Part of the study is to check the population of trout and to notice trends over time and maintain and monitoring data