Looks like it could be a repeat of last year with high, cold water delaying the spring chinook return. This came from the Columbia Basin Bulletin:
Last year – which also featured a high, cold, muddy river – the first count of 100 or more spring chinook in a single day didn’t happened until April 15, and the first 1,000-fish count was on April 25. The counts could build quickly once the fish begin to move.
The forecast for the upriver spring chinook run is 314,200 adult fish, as counted at the mouth of the river.
On average 50 percent of the upriver spring chinook salmon run will have passed over Bonneville by May 7. That 50 percent passage rate has ranged from April 24 to May 12 over the past 10 years.
No chinook have crossed Lower Granite Dam yet (April 9), which is the last dam the fish cross before reaching Idaho.