Time: 12:30PM – 4:30PM
Location: Below Gross Reservoir
My previous two trips to South Boulder Creek could be characterized as relatively straightforward when referring to fly selection. During the early hours I relied on a dry/dropper with a foam surface fly and a prince nymph dropper, and various green drake patterns occupied my line during the afternoon. Although I experienced my share of refusals, for the most part these flies delivered steady action. Based on the favorable outings on 8/15/2019 and 8/24/2019 I decided to return to my home waters on 9/12/2019.
When I returned from my six day trip to Pennsylvania on Wednesday, I reviewed the stream flows of the Front Range creeks, and South Boulder Creek posted a reading of 123 CFS. This level is higher than my ideal range, but the lure of green drake action in September brought me back. On my two previous visits the green drake action did not commence until 2:30 – 3:00PM, so I completed my morning workout and delayed my arrival. By the time I pulled on my waders and rigged my Sage four weight and ambled down the trail to the creek, it was lunch time, so I downed my small snack, before I approached the water.
As I mentioned, I prefer lower flows, and I quickly discovered that the creek could only be crossed in areas where the rushing water spread out over a wide stream bed. This handicapped my efforts a bit, and many areas that offered prime sanctuaries for hungry trout at lower stream levels were off limits at 123 CFS. Another unanticipated adverse factor was the weather. A storm rolled through Colorado on Wednesday night, and it brought a high pressure system that featured cool temperatures and wind. The air temperature in the canyon never surpassed the mid-sixties, and I dealt with sporadic gusts of wind throughout the day. Historically I never seem to do well on the first day after a high pressure system arrives, and I surmise Thursday was one of those days.
Unlike my last two South Boulder Creek visits, I never settled on a consistent approach or fly. I began my day after lunch with a size 18 black parachute ant with a pink wing post, and this choice paid quick dividends, as six fish confidently inhaled the small terrestrial. The gusts of wind suggested that terrestrials might be solid searching patterns. The downside to the ant was my inability to track it in swirling water and riffles. It performed admirably in smooth shelf pools and pockets, but it was difficult to follow in challenging light and through surface chop.
It was likely a case of over analysis, when I swapped the ant for a size 14 Jake’s gulp beetle. I reasoned that the beetle was also a likely wind blown terrestrial food source, and tracking the bright orange indicator foam was much easier than following the low floating tuft of pink poly. The beetle did, in fact, yield two trout, but it was ineffective in several prime areas, so I made another change.
During previous trips I prospected with a parachute green drake in the hours before the hatch, so I revisited this strategy on Thursday. I knotted a size 14 2XL parachute green drake to my tippet and landed two more trout. Unfortunately for every taker I suffered three long distance releases. The trout were interested in the western green drake imitation, but they reluctantly nipped at the large low floating imitation, and when I responded with a timely hook set, they quickly dropped off. I was a baffled by this turn of events, since the parachute green drake was money in the bank in the pre-hatch time period on the last two visits.
By 2:30 I had not yet observed a natural green drake, so I reasoned that perhaps the fish were locked on subsurface nymphs. I took a long break and configured my line with a dry/dropper including a peacock hippie stomper, prince nymph, and salvation nymph. The trout gave this alignment a resounding thumbs down. The hippie stomper elicited several refusals, and I sensed that the large weighted prince was causing the nymphs to drift below the cone of vision of the feeding trout. I removed the prince and replaced it with the salvation in a single dropper arrangement, and this combination duped a brown trout in front of a submerged boulder, when I began to lift for another cast.
By 3PM I spotted some early natural green drakes, and I responded by reverting to a solo green drake dry fly. In this instance I tested a Harrop hair wing dun, and it fooled a nice fish along a current seam, but then it fell out of favor, and I once again pondered a change. I decided to stick with the green drake theme, and I replaced the Harrop version with a size 14 comparadun with no ribbing. The comparadun generated the most success, when it produced three netted fish, and the fish counter moved to fifteen.
At 3:30PM I reached a section of fast water that consisted of numerous deep runs and pockets. I decided to exit and hike back toward the trailhead and stop at one of my favorite pools along the way. When I arrived at the gorgeous wide pool with a deep run slicing through the center, I paused to observe, and several sporadic rises caught my attention. Prior to my exit downstream I knotted a cinnamon comparadun to my line, and now I fluttered a few casts to the right side of the spectacular pool in front of me. A pair of refusals dampened my optimism, so I exchanged the cinnamon size 16 for a light gray of the same size. The gray pale morning dun imitation reversed my fortunes, and I hooked and landed a spunky rainbow and two brown trout, before I called it quits for the day.
Eighteen fish in four hours of fishing is a respectable performance, but it lagged 8/15 and 8/24 in both quantity and size. I suspect that I over analyzed the situation, and I should have persisted with the ant or defaulted to my tried and true dry/dropper in the pre-hatch time period. I never fell into a nice rhythm and or developed confidence in one of my fly choices. I also suspect that the cool temperatures and wind played a role in my inability to attain a comfort zone on Thursday, September 12.
Fish Landed: 18