Now that spring is getting serious, then those most subtle of temperature changes trigger an activity in one of Michigan’s greatest game fish. Steelhead trout take note of some delicate aquatic mechanism and turn their blue-gray noses into river currents and swim.

In the south central part of our state, it is the Grand River watershed that beckons to the big rainbows. The urge to climb the swollen Grand and her tributaries each spring, takes these choice game fish far up the channels of streams where otherwise no trout would venture. Sometimes, like the homing instincts of salmon, it is to the waters of their birth. In other instances the steelhead seems to be seeking that combination of pea gravel, water flow and temperature it instinctively knows will lead to successful spawning. In still other cases it may be seeking to return to the waters where it was released as a fingerling.

But the trigger is the ever so lightly warmer water. When those temperatures reach the river’s outlets in an ocean or one of the Great Lakes (Lake Michigan as in the case of the Grand) the migration begins. Crockery Creek east of Muskegon, the Rogue River north of Grand Rapids, Fish Creek, Stoney Creek and Prairie Creek, between Ionia and Hubbardston, all have their runs of rainbows that first felt “spring” in their hearts and gills, in the waters off Grand Haven.

In the mainstream itself, the Sixth Street dam area in downtown Grand Rapids enjoys the greatest presence of steelheads. The waters below the dam at Lyons has its regular run as well, as does the North Lansing Dam in downtown Lansing.

Still other tributaries where the trout have access also have runs of various sizes. The Flat River, the Thornapple River, the Red Cedar River and the Maple River are all examples.

A human finger dipped in any of these waters may not be nearly so sensitive as the system of a waiting steelhead. So we must rely on other sights and sounds to know when these fish begin to move.

Consider the optimistic early arrival of the red-winged blackbirds to the damp bogs and the swampy shorelines of our streams. Consider the first cold voices of the peepers and toads in half thawed ponds. Something like the mechanisms in trout stir these creatures too, to respond to the most subtle of changes.

So we know the great trout are coming now, and it’s time to meet them in their places of choice. You owe it to yourself.

Check your waders for leaks, your best reels for a smooth and sure operating drag and your line for frays.

Set your alarms so that the chill of a black dawn can be overcome by a second cup of steaming coffee and still give you time for a drive to a distant river.

Climb into all your gear and walk to the water just before the early rays of morning opens up to daytime. Embrace yourself for what the sport is all about.

When the first swirl of a giant protective male fish breaks the silence like a frolicking beaver, and when the vee’s of several fish lift the water’s surface as from the wake of a passing boat, you will have forgotten the cold. You will be ready to cast among those great fish until your hook is fast to one.

Who cares about how those huge rainbows got there and what it was that first attracted them. The fact is that they’re there in the water in front of you—and that’s enough!