All of the hatches mentioned above occur in this stretch of river. While the trout aren’t fussy, they sometimes have their moments. So my dry-fly box always contains a good selection of mayfly, caddis, midge and stonefly imitations, as well as such attractor patterns as Stimulator, PMX, Purple Haze and Royal Wulff. But check the local fly shops to find out what’s hot at the moment.

This brings us to the Middle Section: Jerry Creek Bridge to Browne’s Bridge is the stretch of Big Hole most anglers relate to and where you are most likely to meet early-season competition. What sets this section apart from the others? Habitat! Dewey, Divide and Maiden Rock canyons provide the best, most diverse habitat on the river.

From Jerry Creek to Divide, rainbows tend to dominate, though there are good numbers of browns and, of course, whitefish. “The rainbow stronghold is above Divide,” said Dick Oswald, a Fish, Wildlife and Parks biologist in Dillon, “although the Melrose area produces its share of mature rainbows.”

Between Wise River and Divide, he said, the combination of healthy tributaries and less irrigation means flows and water temperatures that are a little better than in other places. “The aquatic system, including insects, functions better here than anywhere else on the Big Hole,” Oswald added.

Good habitat -- a healthy mix of cold water, riffles, rapids, deep runs and pools, lots of big rocks and log jams -- produces more bugs and on average, more and larger trout.

Fly patterns listed above work well here. Between hatches, local guides commonly rely on a pair of weighted nymphs drifted beneath a strike indicator. There’s now a local joke: “Bugs thick, trout rising all around. Here comes a Dillon guide, bobbers adrift, oblivious to it all.”

But some make a career of stripping streamers and chucking dry flies almost exclusively in the canyons.

Al Lefor, of Great Divide Outfitters, tests the waters with streamers early on, switching to dries once the river warms a bit. When he drags out the nymph box, prospects are grim and only expected to get worse.

The Lower Section, Browne’s Bridge to Twin Bridges, is well-known for harboring trout measured in pounds and fishes well throughout the early spring. In recent seasons, overall numbers of browns 18 inches and larger have declined somewhat. But the lower river remains a favorite haunt of big-trout specialists.

The most dedicated are out there almost every day, from ice-out through early summer. These guys toss huge, heavily weighted streamers and net browns most of us only dream of. But this is tough, demanding fishing. Near-misses tend to outnumber actual hook-ups by a wide margin, and there are no guarantees a hooked trout will end up in the net, not by a long shot.

This sort of fly-fishing requires more faith and perseverance than most of us possess. But those who seek really big brown trout could do far worse than chucking and ducking the lower Big Hole.

For those of us inclined to more mundane pursuits, everything said about the upper river goes here -- except that browns and whitefish rule, and there are fewer rainbows. Brookies, cutts and grayling are few and far between. Fly patterns and tactics for the upper river work here, and this section also suffers during dry summers. Irrigation demands, combined with the high-desert conditions reduce summer flows drastically.