Passive integrated transponger tags are used to monitor individual fish. The tag, 12 mm long, is inserted in the fish's body cavity and contains a microchip programmed with individual fish ID codes. The system yields information about passage times of individuals at pittag observation sites.Fish are measured at the time of tagging
Release cohorts were formed by combining releases from up to 5 consecutive days to achieve observed sample sizes of at least 19 individuals. 48 cohorts were constructed from 113 releases over 5 years. The cohorts were edited to remove fish with travel times greater than 60 days.