Things are Moving!


Our apologies, we've been very busy elsewhere and have neglected our steelhead duties, so it's time to get back on track.
    Where to start???..... All kinds movement going on up and down the North Shore. The Knife had a pretty classic ice-dam signature which shows all the indications that the ice pack is finally breaking up. It's always a bit of a crap-shoot with the flows when you see this kind of signature, but our best estimate given the data we have is that the Knife is now running around 275CFS under all that ice.
 
    Mid-Shore streams are moving as well. The Baptism must have a fair amount of open water in and around the upper reaches. Water temps in the lower river were climbing into the mid-33F range which usually indicates open water somewhere. We only see this starting during the initial stages of ice-out when the stream-bed is exposed and the sun is heating the bottom. The bottom absorbs solar radiation and re-radiates it into the water helping the water temps to climb. 
 
Upper-Shore streams are showing the same thing. We have first-hand reports of open water, and the temp readings have also been climbing into the mid-33F range during the day.
 
    The only thing slowing things down at this point is illustrated in the graphic above. The magenta line shows stream temps climbing and peaking on a daily basis following the solar cycle. Basically you get the most heating between late morning and mid-afternoon. Not only does this warm the streambed, and consequently the water from re-radiation, it also accelerates snow-melt in the river valleys. The problem until we get rid of the majority of the snow is that the meltwater entering the streams is still very cold. You can see the effects of this in the graphic, The increase in flow (the blue line) from increased snowmelt is pumping cold water into the river which is bringing the temps (magenta line) down.
 
What we're waiting for now is for the avreage daily stream temps to hit that roughly 38 degree F mark with daily high temps in the 40+ range. We know from the literature that this, at least with respect to the North Shore Steelhead fishery, is the trigger for that first initial upstream migration push of adult steelhead.
 
    Of course, none of that is to say you should wait. If you can find open water, whether it's in the stream or out off the mouths and you have the opportunity, it looks like it's time to dust off the rods and hit the water.
 
    Oh, and I almost forgot: That river on our neighbors over to the east has fish in it and is running at around 270CFS at the moment. Lots of nice fish being caught.
Regards-
NMF

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