I made a firm resolution that this spring I would get out and do a lot of birding, and so far I have been able to keep it. In the past couple of years, a combination of work, family responsibilities, and household chores reduced my birding opportunities to near zero. I was spending more time sitting and writing about birding than I was actually looking at birds.

You can’t do that forever. Writers live off their experiences. If you don’t get out, pretty soon you’ll run out of stories. And, like other complicated games, birding demands frequent practice. If you don’t do it, you’ll lose your eye, just like a basketball player coming back from an injury has to take extra practice to get his jump shot working.

Good birders need two different kinds of skills. First, they have to be able to notice movement anywhere in their field of vision, whether it’s the darting of a wren in the shrubbery or the passing of a soaring hawk high overhead. Some people are just naturally better at this than others, but everyone can develop greater skill with practice.

Second, they have to notice subtle differences in shape, size, proportion, and behavior–clues to identity that go beyond the eyebrow stripes, wing bars, and rusty tail feathers that the field guides typically provide as field marks. We all go through this kind of process with people. We need a good look at the face of a new acquaintance in order to recognize him the next time we see him. We can identify old friends when they are half a block away just by the shape of their bodies and the way they stand and move. We can recognize our spouses in total darkness just by listening to the sound of their breathing.

Then there is the simple matter of remembering the enormous mass of information that birders have to carry in their heads. Is it the greater scaup or the lesser that has the rounder head? Which waterthrush has the wider eyebrow stripe?

My experience is that if I don’t use all this data, I lose it. Four years ago, when I was in Arizona, I carefully memorized the subtle differences that separate the three local species of Myiarchus flycatchers from each other. If I went back now, I’d have to memorize them all over again.

This spring I have been doing most of my birding at Montrose Harbor. Montrose seems to be the best place in the Chicago area to observe the spring migration. The fact that it sticks out into the lake a good half mile beyond the rest of the nearby shoreline makes it a good landing spot for northbound birds whose flight path has carried them a bit too far east. The lake provides the gulls and waterfowl, the beach is good for shorebirds, and the parkland attracts the land birds.

Montrose also offers a clear look at the rhythms of the migration season. Migration is not a steady flow. It proceeds in waves, primarily in response to wind shifts. When a warm front moves in with southerly winds behind it, the birds who are riding those winds come in with it. When a cold front arrives and the wind shifts, the migration stops. The birds lay low and wait for good flying weather.

The biggest wave I ever saw blew through Chicago on May 7, 1983. I was covering Montrose Harbor for the statewide Spring Bird Count that day, and I knew something special was happening when I stepped out of my car at the east end of the harbor at 5:30 AM and was almost hit full in the face by a flying nighthawk.

For the previous week a stationary front had been sitting in central Illinois, holding several million birds behind it. During the night before the count the front moved north, bringing southerly winds in excess of 30 miles an hour and all those millions of birds. Just strolling from harbor to beach and across the lawns I ran up a list of 74 species. The winds were forcing birds that usually stay in the treetops to get down on the ground, and at one point I aimed my binoculars at a patch of grass and counted 15 birds of six different species in my field of view simultaneously.

In midafternoon the wind shifted to the north, the temperature dropped about 20 degrees, and a violent thunderstorm soaked me and messed up my binoculars so badly I couldn’t see through them. At that moment my 74th species, a great horned owl, landed in a tree about 30 feet from me.

The next morning the temperature was only 40 degrees and a 14-mile-an-hour wind was blowing out of the north. On a brief visit to Montrose, I could find only 15 species. Montrose Harbor lets you see the rhythm of migration–both the crests and the troughs.

This year I have had nothing quite so dramatic as that day in 1983, but the ups and downs have been just as clear. My best sighting so far was of an immature peregrine falcon perched in a tall cottonwood at the edge of the beach. She (he?) was very cooperative, allowing me to walk all the way around the tree and view him (her?) from every angle. Peregrines are big-headed birds, and their bulky flight muscles give them a big-chested look. Those muscles help them reach speeds of 200 miles an hour, making them the fastest-moving animals on earth.

Sometimes surprise provides the excitement. Giving a casual glance to a flock of ring-billed gulls on the beach and suddenly noticing that two of the birds have very short legs, big red beaks, and black crests–the first Caspian terns of the season. A few days later I watched one Caspian tern flying about with the tail of a fresh-caught smelt dangling from its beak. Several other Caspians were chasing it, apparently trying to force it to drop the meal.

Watching a flock of red-breasted mergansers in flight, I see a loon flying with them, looking like a Clydesdale in a pasture full of Shetland ponies.

I love watching the Canada geese. Just a few years ago we saw Canada geese briefly in early spring and late fall. But now they are with us year-round and in ever larger numbers. One pair is swimming around the harbor with six downy young bobbing in its wake. I see others just standing on the lawns, five or six birds, each three feet tall. Their presence seems miraculous. Golfers complain that the geese foul greens and fairways with their droppings, but I’ll take geese over golfers any day.

I’ve also made a couple of visits this spring to a place I call South Prairie. It is definitely south–its northern boundary is 167th Street –but the prairie part is just my imagination. It is really weedy old fields dotted with scattered patches of very young woods, but if it was ever restored to prairie, it would be one of the most glorious places in Illinois.

It is big: a mile wide and a mile and a half long. And it lies on a moraine, so there are actual hills and valleys. One of the valleys has a good-sized pond, where I see geese, blue-winged teal, ring-necked ducks, shovelers, lesser scaup, and coots. There is never anybody else there when I go, and from down in the valleys I can scan the whole horizon without seeing any signs of human intrusion.

The Cook County Forest Preserves own the land, and there is a proposal backed by local municipalities to turn part of it into a sort of agricultural theme park featuring replicas of Illinois farms through history. I hate this idea–which, by the way, has nothing to do with the reason we have a forest-preserve system–and one of the reasons I go birding at South Prairie is to gather ammunition against it.

The harriers are the best thing I’ve found so far. I saw one on my first visit, March 17, and two, a male and a female, on April 14. The female gave me a perfect look. Harriers are big hawks whose hunting method involves flying low over open land. Seldom as much as ten feet off the ground, they come upon their prey with terrifying suddenness. I saw the female sitting in a small tree some distance from where I was standing, and as I watched, she took off and flew toward me, quartering over the ground, turning her head from side to side, looking for movement in the grass. I could watch her eyes as she hunted.

Harriers are an endangered species in Illinois, so if these birds nest on South Prairie, they would give us some strong evidence of the biological value of this preserve and perhaps help head off the farm museum.

I’m also watching the arrival of the prairie songbirds that nest here. The eastern meadowlarks were first. A few were on hand in March. When I walked through the preserve in mid-April, I was never out of earshot of a singing male. Now, in late April, the savanna sparrows are arriving. Soon the bobolinks will join them, and I’ll start hunting for grasshopper sparrows and Henslow’s sparrows.