The Mother's Day Caddis Hatch

[Al Agnew]

The highlight of spring on the Yellowstone River in Montana is the Mother's Day caddis hatch. The hatch actually usually happens sometime around the first of May, but it's tricky. The water temps need to get up to 50 degrees to start the hatch, but when the water temps get up there, a lot of times the snowmelt up in Yellowstone Park on the headwaters also starts, and the river quickly gets blown out for the rest of the spring.

This year was strange. As of two weeks ago, thanks to several days with temps in the 80s, the water temp had gotten up into the mid-50s. It was early for the hatch, but Sunday two weeks ago, we did a float during which the caddis started showing up. Not in the huge numbers that happen at the height of the hatch, but enough caddis that there were thousands of them in the air, flying around and occasionally dropping to dip into the water and deposit a few eggs. But they weren't floating on the water and the fish weren't rising to chase them in the air. And the high water was coming. It would reach Livingston starting the next day. I caught a few fish on nymphs and one nice one on a streamer, but didn't even try a dry fly.

The river shot up a good 2.5 feet and got brown muddy the next few days. But the weather changed as well, and the temps dropped back down into the low 50s, with strong winds and cloudy, sometimes rainy weather. It slowed and then stopped the snowmelt, and the river began to drop. I went down to the water a couple times in the evening to see if anything was happening, but the caddis were gone and the fish weren't doing anything; I hooked one fish on a streamer.

Today was finally a warmer day, temps up into the 60s, moderate wind, mostly sunny. I worked in the studio all day until suppertime, and when I walked from the studio cabin to the house, there were caddis in the air. After supper Mary and I walked outside and looked at the river, and there were more caddis in the air. I said I should be fishing. Mary suggested that I put the litte Watermaster raft in at the house and float the four miles down to the Hwy. 89 bridge and she'd come and pick me up at dark. She didn't need to talk me into it.

The wind had come up a bit and was blowing upstream. The river was still a little high, with about two feet of visibility. Not perfect conditions for dry fly fishing. The caddis were sporadic. There were some in the air about everywhere, but along the banks there would be little pockets where there would be about a thousand of them in a spot the size of an automobile, along with about a thousand more midges. But almost none on the water, and no rises. I started out fishing a streamer, while watching for any indication of rising fish. Nothing was happening on the streamer, so when I saw two small fish rising along a stretch of bank, I tied on an elk hair caddis a size bigger than the real bugs. I caught one of the two, an eight incher, and hooked the second, a 10 incher that jumped about five times and finally got loose.

When the fish are really up and feeding, you can just drift along the banks letting your fly drift with you, and sooner or later it will drift over a willing fish. But there were still few bugs on the water and few fish rising, and I floated a long way with no action before finding a group of rising fish. The sun was sinking fast behind a low bluff, with strong current out in the middle but slow current along the bluff and a soft current seam about 30 feet off the bluff. Most of the fish were rising out in the current seam. I slid into the slow water, and started watching for rises. They weren't quite rising steadily, more like one or two rises at a time, with maybe 30 seconds until another one or two rises. I started with a fish rising at the upstream edge of the eddy, a short cast length away. It took on the second drift, a pretty 13 inch rainbow. I watched until I saw another rise just downstream, and that one took on the first drift. And so it went. I'd hook or catch a fish, watch for 30 seconds to a minute until I saw another rise, and then hook or catch that one. I got, as far as I could tell, every fish that was rising in that eddy to take my fly, about 15 or so in all. That's the nice thing about the beginning of the caddis hatch; it's the first major hatch after a hard winter and the fish aren't picky.

By that time, darkness was fast approaching. As I drifted on down, watching for rises, I saw a fish come up over close to a rocky bank in reverse current, requiring a long cast with a sharp current seam between me and the rise. I know how to mend but it looked pretty difficult. I'd marked the rise by a distinctive rock on the bank adjacent to it, and I quickly decided I'd have to make a long, accurate cast that would land the fly just a couple of feet "above" (actually downstream but upcurrent) where the rise had been, because that was about all the drift I would get before the differential currents would mess it up. The cast landed just where I wanted it to (and believe me, that doesn't always happen for me!), drifted the two feet, and a big nose came up and the fly disappeared.

I had the fish on for a while, long enough to know it was a very good one, at least 20 inches. But I didn't get it in. Oh well, the triumph was in that perfect cast and just enough good drift.

I picked up a couple more along that bank, including the best one of the evening, a 17 inch rainbow. And then it really was getting dark and I had one pretty rough little rapid to negotiate just above the take-out. I called Mary on the cell phone to tell her I was ten minutes from the take-out, and rowed through the rapid with no problem. I was just carrying the little raft up the ramp when she drove up.

Tonight the temps are supposed to drop into the 20s, with snow down to 5500 feet elevation (our house is at about 5000 feet). Tomorrow it will be rainy and cold. But Sunday it will be sunny and up into the 60s. It will be interesting to see if the caddis pop out again Sunday, and maybe I'll be on the river if they do! I'm still hoping for the REAL Mother's Day caddis hatch, where there will be millions of bugs in the air and on the water, caddis so thick that they float in mats that we called "caddis pizzas" when we saw it years ago, so thick that their lime green egg cases coated the bottom and covered every part of our waders that was underwater, so thick that if the wind was blowing, whichever side of our bodies that was facing the wind was totally covered with caddis. Maybe it won't happen this year. But at least I got a taste of it today.

[Mitch f]

I think you found a great lady in Mary... When I say " I should be fishing" I only get a good response 30 percent of the time!