Columbia Shad Count

[Bait O' Eggs]

Can somebody explain how the Bonneville Shad count is 1 fish year to date and the Dalles Dam has a 2 fish year to date shad count? Either the counting is off by 100% at Bonneville or one of these stinking fish swam up the spillway (not likely).

[Wisdom]

Well, your second option is likely and does happen. The shad do migrate up through the locks. If you notice throughout the entire run, you will get a higher total passage over the Dallas dam then over Bonneville. The tribes have dipped huge numbers of shad out of both the Dallas and Bonneville locks.

[Pete]

It's true, some fish evade counting by going up the locks ... shad really like the locks ... and others get counted twice by going down the locks or the spillway and coming back through the counter. It happens with salmon and steelhead, too, but not as much.