My list for this year’s statewide spring bird count included 50 species of birds, two species of amphibians, and one reptile. The reptile was a pretty-good-sized specimen of the northern water snake that I saw just a stride before I would have stepped on it.

The snake and I were both lurking in the weeds at the edge of a marshy pond in a forest preserve south of the city. He moved slightly as my foot approached, and I caught the movement and stopped still. We both remained motionless for a time, studying each other.

The sight of a snake in the wild always gets my adrenal glands pumping. Some of this is just startle effect–you almost never see a snake until you are about to step on it. But there is more to it than that. I’ve flushed woodcocks from directly beneath my feet without noticeably upsetting my endocrine system.

I could speculate on primeval fears, but I suspect my reactions are nothing more than the result of being raised by a seriously phobic mother who gets nervous if she encounters a picture of a snake.

My snake had a tan body marked with dark chocolate brown rectangles down its back and smaller, irregular blotches on its sides. According to the books, this is the typical pattern of the northern water snake, but the books also say the snakes get darker as they get larger. On big snakes the pattern may be so mixed with the ground color that it can’t be seen except by very close examination in good light. And since my snake was 12 feet long–well, actually it wasn’t 12 feet long, but if it was short of three feet it wasn’t by much–it should have been much darker.

My chance to look closely at the animal lasted not more than ten seconds. Then it thrashed violently once and burrowed under a floating mass of last year’s cattail leaves and other detritus.

I checked with Ellen Beltz, my chief consultant on matters herpetological, about my unusually pale snake. She told me that the colors were temperature dependent. The colder the place, the lighter the snake. Chicago’s climate makes tan snakes.

She also told me that I could identify my snake as a male because of the length of its tail. You might wonder how you separate a snake’s tail from the rest of it. At first glance a snake is all tail except for a few inches of head. But the tail is the part aft of the vent, the all-purpose opening in a snake’s belly that serves for waste elimination and sex. The tail tends to be noticeably slimmer than the rest of the body. My snake had six inches or so of tail. If it had been a female the tail would have been only a couple of inches long.

The presence of a snake, especially a snake that is not a garter snake, confers a sort of pedigree on a natural area. When an area begins to decline, to move from its natural state of diversity toward the degenerate uniformity of landscapes overwhelmed by human intrusions, the reptiles and amphibians, the things that creepeth upon the earth, are usually the first to go.

When natural areas are turned into islands, as nearly all of ours have been, birds and some mammals can move from one island to another. They can colonize attractive places and move away from inhospitable lands. Herptiles don’t have that kind of mobility. Imagine a northern water snake trying to cross I-57.

So the marsh whose edges the snake and I were patrolling qualifies as a good place, a judgment reinforced by the chorus frogs I heard there, the soras and common snipe I flushed from the cattails, and the pied-billed grebe I saw sinking beneath the surface of the open water.

The statewide spring bird count is held every year on the Saturday that falls between May 4 and 10. This is an ideal date for Springfield, but about a week too early for Cook County. Some years we completely miss migrants that will be common by May 15.

This year the season was even less advanced than usual on Saturday, May 6, and no large waves of migrants had passed through yet. I was assigned to cover the Bartel Grasslands, an area I really like because it has some very interesting resident birds. Even if the day is poor for migrants there is always good birding to be had there.

The Bartel Grasslands were named by birders in honor of Karl Bartel, a pioneering local conservationist who died a few years back. The name appears on no map. It is kept alive by oral tradition within the birding community.

The grasslands are part of the Cook County Forest Preserves system. Their southern end is at Vollmer Road, which, if it had a number, would be 200th Street. They are part of a block of preserves that extends along both sides of Central Avenue from Vollmer to 159th Street.

Some beautiful old oak groves dominate the preserves at the north end of the block, but most of the land used to be cornfields. Except for some young woods planted by the Forest Preserve District, it is now a mixture of open fields and marshes.

Of my 50 species of birds, only two can be certainly identified as migrants: the white-throated sparrow and ruby-crowned kinglet. Both of these birds nest in the North Woods and not in northern Illinois. And both of them are birds we expect to see in April and not in May.

The main attractions in the grasslands are prairie species, and the best of these are the bobolinks. They are among the open-country birds that make up for the lack of trees for singing perches by singing in flight. Their song is long, elaborate, and tinkling, and I always wonder how they have enough wind to sing it when they are also flying across the fields. Walking on the grasslands is a delightful experience, as the singing bobolinks convoy the hiker across the fields.

I managed to find one upland sandpiper, a bird we do not usually see in Cook County except at the Bartel Grasslands. I found only a few savannah sparrows–16 birds–and those were almost all individuals I flushed as I walked across the fields. Only a few males were singing, probably because the count day was so early in the season. Grasshopper sparrows and the threatened Henslow’s sparrow are usually found on the grasslands, but I couldn’t find either one. They are migrant species, and they may not have arrived yet.

I wore my Wellingtons to check out the marshes. Over the years I have vacillated on the question of whether it is better to wade with Wellingtons or just to wear old, beat-up running shoes and get wet. In warm weather getting wet is no big deal, and wearing Wellingtons you always face the possibility of stepping into water that is just an inch too deep. Walking in water- filled Wellingtons is the worst of both worlds.

I had decided on the Wellingtons for the count because of the long walks I would have to take from marsh to marsh. Long walks in wet shoes and socks are not fun.

Thanks to the Wellingtons, I found ten sora rails and two Virginia rails in the marshes, as well as marsh wrens, swamp sparrows, coots, pied-billed grebes, and the snake. The Wellingtons also provided me with the most joyous experience of the day.

Walking south from the marsh where I had seen the snake, I heard an enormous noise coming from the open fields just ahead. It was so loud and unrelenting that at first I thought some sort of machine had been set up in the field. But as I got closer, I realized that what I was hearing was a whole lot of toads singing together to produce a glorious racket.

But all I could see ahead of me was open field. American toads sing from marshes, but where was the marsh? I didn’t actually see it until I was already in it. I was following what remained of a two-track dirt road, and all of a sudden the water in the tracks was too deep for my Wellingtons. Amid the upland grasses were cattails, last year’s seed heads now shaggy, seemingly covered with the sort of hair clumps my golden retriever leaves on the living-room rug.

I walked very slowly through the ankle-deep water of this odd place. I flushed a pair of mallard and a sora and then, by standing very still, managed to see a pair of Virginia rails watching me from the cattails. Behind me was the rattling song of the marsh wren, and dragonflies darted low over the water.

That’s when I realized what I was seeing. Once, when this was a cornfield, drainage tile buried well below the ground had kept it dry. After the Forest Preserve District bought the land the tile was allowed to deteriorate, and it is no longer functioning. The old field is now home to rails and marsh wrens and some of the loudest toads in the land. Isn’t that delightful? And they say that environmentalists are against progress.