Wednesday, July 1, 2009

The Need for Speed - Salmon Migration Speeds in the Columbia River

Like the last post, we've gleaned some interesting information out of the Fish Commission's reports (www.critfc.org). We've always wondered about how FAST those salmon are moving upstream. The CRITFC has been tagging fish at Bonneville, and tracking them as they speed upriver. And those dudes are speeding!

According to the reports, Spring Chinook move upstream at a speed of 21miles per day. Fall Chinook average 24 miles a day - they've got eggs to deliver, man! If you assume a steady rate of speed (night and day) then 24 miles per day is almost 1.5 feet per second. Thats a pretty good clip!

From a separate report, smolt salmon are moving DOWNSTREAM from Bonneville at rates as high as 50 miles per day. True, they have the current helping them, but these are the little guys - at 3 feet per second!

I can hear the springer's comments as the little dudes wizz by downward... "wish I still had that kind of energy!"

The implications of a fall chinook heading upstream at 1.5 feet per second (average) in 50 feet of water means that fish has about 2-3 seconds of "face time" with our lures when we are fishing. The visibility that deep is about 3-5 feet (ave), so every second counts. Sometimes its a wonder they stop to nibble at all... and also explains those explosive 'take-downs' that keep us up there sitting on anchor - they don't have time to waste on a nibble!