Judging by the fresh snow in the high country, and the Aspen groves showing their reds and yellows, it looks like fall has begun. What a time to be a fly fisher!
Low water on the Río Grande is a good thing for us fisher-folk. Water flows have been under 100 cubic feet per second (cfs), at the Cerro gauge, most of the summer and continue to be steady in the 70s. At this flow, the upper part of the Río Grande — Wild and Scenic Rivers — is comprised mainly of natural spring water. Springs tend to be very nutrient rich, with a constant temperature that’s just about perfect for trout. Cooler weather has triggered the start of fall hatches, mainly the Baetis Mayfly, and the summer crowds have headed back to the Plains.
The Baetis is a small mayfly that is essentially a smaller version of the Blue Winged Olives (BWO) that hatches in the spring. While Spring BWO’s are about a size 14-16, Fall Baetis will range between a size 18 or 20. Like their spring counter parts, they will hatch around mid-day. Cloudy, humid days will produce the thickest hatches as well as inspire the fish to feed.
Though some dry fly action is possible, especially as we get later into the fall, most of the fish caught on the Río this month will be taken on nymphs. Imitate the emerging Baetis Nymphs with size 16-18 tungsten mayfly patterns and you will have success. Be aware that, like all mayflies, Baetis live and emerge in shallow riffle water. Don’t fish the deep slow stuff, but instead focus on moving water in the 1to 3-foot depth range. If fish do start to rise, don’t hesitate to put a size 16 Parachute Adams or Tilt Wing Dunn over their heads.
Another great fall fishery, the Red River, should fish particularly well into the winter. Many Río Grande trout seek the warmer waters of the Red for spawning. And given the robust Río Grande fish populations this year, we should see a good push of fish in the Red this year.
Another consideration in fishing ventures should be Eagles Nest Lake. Though the water level is down and the fishing has been mediocre this year, it should improve as the Moreno Valley sees its first hard freezes, and the weeds in the lake start to die off. Small Woolly Buggers should give you a shot at trout and perch while larger streamers with wire tippet may hook up a big northern.
Some of the best fall fishing will occur on cold, cloudy and nasty days. It’s important to transition your gear with the changing seasons. Make sure your waders are not leaking. Pack your long johns, good socks, and fishing gloves. Extra layers are good to have as well, and a warm knit hat may come in handy too. The ability to stay on the water and fish comfortably during inclement weather may be the advantage you need to hook up the fish of the year.