Adult Anadromous Fish Radiotelemetry Project (1996-2004)

Event Summary Query

Approach: Detection of a fish near the base of a dam; records are 'coded' for the first and any subsequent approaches to a dam. Efficiencies are not calculated for approaches as they are not associated with a specific route at the dam.

Entrance: a location in a dam structure where there is access to the fish ladder system for migrating adult salmonids. Fish entrances are noted and tallied at entrances with receivers.

Exit: the action of a fish leaving a fishway through a downstream path after it has entered a dam fishway.

Fallback: an event in which a fish is detected at a location downstream of a dam after having been above that dam. These are determined either by records showing the fish's actual passage route back over a dam, or assumed when a fish is recorded downstream of a dam after it has originally passed. Fallbacks are one source of delay in a fish's migration, or can occur if a fish overshot its natal stream.

Passage: the act of traversing a dam as part of the upstream spawning migration. Passage times are calculated based on the time of a fish's first approach to a dam and the last detection of that fish at the top of a fish ladder.