Klondike River Sonar Project

The primary objective of this project is to enumerate the 2011 Chinook salmon escapement into the Klondike River system. A site 4.5 km upstream of the mouth of the Klondike River was selected during a Klondike River sonar feasibility study in July 2008 and May 2009. This site was chosen for the 2009 and 2010 projects and is again the designated site for the proposed 2011 project. This location has a total wetted river width of approximately 53 m with a maximum depth of approximately 2 meters. The cross section profile at this location is conducive to providing complete ensonification of the water column with no acoustic shadows or blind spots.

The Klondike River is considered to be a suitable Chinook salmon escapement index stream using high definition sonar because:
1. It is accessible;
2. It has documented significant Chinook escapements;
3. It is recognized as a genetically unique and identifiable stock;
4. It is unlikely that co-migrating similar sized fish species will be present;
5. It has discharge volumes too high for a conventional salmon counting fence but low enough during periods of Chinook passage to allow complete ensonification of stream width;
6. The Klondike River Chinook stock is one of the earlier temporal segments of the above border Yukon River Chinook run.
7. Chinook were successfully enumerated using a DIDSON sonar on the Klondike River in 2009 and 2010.

In addition, we will sample post-spawn fish for age-sex-length data and obtain genetic stock identification (GSI) samples.