Fly Fishing The Colorado River Salmonfly Hatch, Monday Morning Update – May 14, 2012
May 14th, 2012
This past weekend saw overcast skies and cooler temperatures overall, with that we saw a slowing of the Salmonfly hatch on the Upper Colorado. Water temperatures have dropped every day from their highs last Thursday, thus interrupting the emergence of additional adults. There are still plenty of adults around as well as nymphs that are still looking to hatch, they just haven’t been as active in weather that has been more conducive to Baetis activity.
River levels have remained low and steady at just about 400 cfs., with clarity varying from 15 to 36 inches depending on the day and location on the river. All of this makes for some fantastic wade fishing, as well as good float access although, that is a little low for most hard boats, rafts may be a safer bet.
The forecast for this week calls for a return to high sun and warm air temperatures bringing water temps back up to favorable levels for the hatch. The actual emergence generally happens at night, with the nymphs crawling out of the water to a high, dry perch to shed the exoskeleton. Morning will bring new adults to bank side willows and bushes, where they will be visible to wading anglers, hanging out and conducting their mating activities. As we mentioned on our fishing report, they are not the surest climbers or fleetest fliers and are prone to falling into the river when attempting either. When you notice adults taking to the air, that is the best time to work the dries although, large dry patterns can work along steep or willow lined banks throughout the day.
The hatch thus far has been below Kremmling, from Gore Canyon on down to State Bridge. Look for it to intensify there again over the next couple of days, especially up into Gore. With the below average water level, water temps are climbing quickly, some days there is a 10 degree swing from the over night low to late afternoon high. This should cause the hatch to be very intense in locations where it is happening but, also short lived, as the hatch will advance upstream as water temperatures climb through the column.
That being said, we have had good reports of a strong nymph population in the upper reaches of the river near Parshall and in Byers Canyon. Anticipation is strong that with the non-existent run off, anglers will be able to take advantage of the hatch along the upper river this year due to strong conditions for both bugs and wading. Look for that to happen at some point over the next week to two. We will have guides out on the water everyday this week and will continue to update the advancement of the hatch and any pertinent information.