Assessment of Live Transport of Adult Atlantic Salmon in the Penobscot River, USA

Hydroelectric dams pose a significant barrier to upstream migration of anadromous species.  Live transport of migrating fish around dams is one management option that can be used to increase migration success to spawning grounds.  However, because live transport involves considerable handling time and may lead to disorientation, it is important to monitor such efforts to understand whether or not it is effective.  In 2010 and 2011, live transport of adult Atlantic salmon was attempted in the Penobscot River in Maine, USA.  Returning adults were captured at the lowest most dam (Veazie Dam) and either transported above the next two dams or released above Veazie Dam.  All fish were tagged with Passive Integrate Transponder (PIT) tags.  In addition, PIT arrays were installed at several fishways in the Penobscot River to monitor arrival success and passage success at dams within the river system.  Results suggest that live transport resulted in a significant increase in arrival success to the upstream dams.  In addition, live transport resulted in a significant decrease in transit time from Veazie to the upstream dams.  However, there was no difference in passage success at the upstream dams among adults that were transported and those that were not.