I am not a big hatch chaser. I am more of the mind set that I am gonna fish when I have time to fish and if there is a hatch going on then great, if not I will fish what ever I need to to catch fish. That said one hatch that I plan on fishing and chase is the late summer/early fall Isonychia hatch on a few local rivers. I Love this hatch as it comes off at a time when most trout anglers think trout fishing is firmly rooted in the summer douldrums and many are staying home bidding their fishing time for the fall.
Isonychia are a mayfly, and not of the BWO/PMD variety, these things are big. Most of the nymphs in my local waters are #8-10 and the adults are an easy #10 if not an #8 early on in the hatch. The nymphs began to get active right around labor day weekend and the hatch begans usually a few days or weeks later, peaking around mid september, all depending on the weather. A heat spell can shift things a bit as can a cold spell. When the fish are keyed in on the hatch they will eat the nymph all day and hit the adults with oportunistic vengence. Leading up to and during the hatch fish will key on swung adults in the riffles and runs.
The nymphs are swimmers and found usually in rocky freestone streams with some mud bottoms in places. When it is getting time to hatch the nymphs began migrating towards the bank and actually crawl up on rocks and emerge out of their nymphal schuk like a stonefly on the rocks. On bigger rivers though they can be seen emerging like a standard mayfly as well, bottom line is you can't miss them on the water and you can't miss the schucks on the rocks.
The Nymphs are a blackish/purple color with a long slender swimmer nymph profile and the adult is a dark purplish/gray. I have developed a few patterns to fish this hatch. The most successful pattern I have come up with is "Hogan's Isonychia nymph". I fish this pattern under an indicator with plenty of split shot and then if I know the hatch has been coming off I will swing this bug through runs and tail outs prior to the hatch starting. Once the hatch starts I fish a parachute adams or a few emerger patterns that I am still tweaking a bit. The big thing to remember during the hatch is that these bugs emerge on the rocks and are only on the water to lay eggs for the most part.
Chasing hatches is not my bag as most of the time an angler finds more people on the water than bugs (remember I live in California). The Iso hatch is not that way. I have been fishing a few local rivers lately chasing these bugs and have yet to see a sole. Mind you these are waters that would be PACKED in the spring and are just not associated with doldrum fishing.
I love this hatch is it reminds me of the big bugs of spring right before the small bugs of fall and the even smaller bugs of winter become the norm.
In other news...A great victory for the Irish this past saturday against a pretty tough Purdue team. The Kelly era is looking good as the team played with an intensity I hadn't seen under Charlie. Running game looked great and Christ spread the ball around and played a conservative game at QB which is nice to see after Clausen. I think the Defense needs some work but looked much improved against a quality Purdue team. Next week we have Michigan...and I hate Michigan and Rich Rodriquez...but I have to give them credit they looked good against UConn (who beat us up last year). Mich's new QB looked solid and it looks like Rodriquez finally has the athletes at Mich to run his spread offense. Either way it is gonna be a hell of a match up.
Other than that Go IRISH, Giants keep it together and get in the playoffs, fish - start eating eggs soon