Birds blow by on a screen of snow: larks, robins, blackbirds, all moving north against us as Minnesota falls behind. A dark hawk slides behind trees in northern Iowa. A turkey tiptoes out of a woods. It is mid-March, and my friend Mike and I are going to Texas to look at birds. We first detour into southeastern Iowa to find Eurasian tree sparrows.

My guidebooks show the Eurasians next to house sparrows. There is an apparent cousinly relationship that doesn’t look true in Burlington. The house sparrows look unwashed, tree sparrows bright and clean, crisply colored, obviously different at a distance.

Seriously on our way to Texas now, we follow the western shore of the Mississippi River, passing 20,000 canvasbacks on the water south of Fort Madison, Iowa, ducks as far as you can see up stream or down. We drive into the depths of Missouri, cross a state line, ricochet off suburban Memphis, cut diagonally into Arkansas.

We have driven, I am certain, for days through Missouri and now weeks across Arkansas. It seems endless. All the mobile homes begin to look alike. There are no birds.

At 6 a.m. the next day we are on the road again, in rain. We need three hours of driving to get to Jones State Forest across the Texas line, where we hope to find red-cockaded woodpeckers.

The road is lined with barbecue joints, most of them small, some no larger than a comfortable ice-fishing house. Many are in mobile homes. One is in the middle of a huge junkyard. Fronting an auto-repair business is a stained sign: “Mechanic on Duty. Spot Welding. Hot Lunches.” We drive on.

The woodpeckers are just where they are supposed to be in the state forest, working quietly in the midst of a colony area, the nesting trees all marked with vivid green paint, thank you very much. There are pileated, red-bellied and downy woodpeckers, too, with pine and prairie warblers, titmice and cardinals. The pines are tall, the brush beneath them thick, perfect for the white-eyed vireos that call and call in the morning rain.

The next day we are in Galveston, on Boddeker Avenue, along the outer beach in a serious downpour. We are looking for the kelp gull that has been seen here for two winters. There are thousands of black skimmers, laughing gulls, shorebirds, white and brown pelicans, rails, herons, egrets, terns, but no kelp gull. Offshore, ships glide in the rain, far away, each towing a cloud of gulls. Now we know where the target gull is.

We check into the Marine Motel. Our room smells of seawater and body fluids. It has sheltered too many spring breaks. The sink is plugged, coated with something black. A man comes to fix it, forcing a long wire into the drain, then violently pushing and pulling.

Mike leans into the room to see what is happening. I watch bits of black goo fly over his head. Some sticks to the bathroom wall. Mike says he will get us another room. The new room has a flowing drain but doesn’t smell any better.

We leave Galveston the next morning, taking the ferry to Bolivar Flats, where we find a huge flock of American avocets. They loaf and feed on tidal debris along the beach.

Many birds are sleeping, thousands of heads beneath thousands of wings. If we come too close, hidden eyes see us and the nerves of the flock flicker.

At midafternoon, the tide shifts. The water begins to move toward our shoes. Suddenly, the avocets are a marching army of feeders, wide awake, rank and file sweeping parallel to the beach line, heads swinging, bills splashing. You can hear them cut the water. Occasionally a bird captures a large morsel and stops to manipulate a gulp, then skips back into step.

High Island is next, up the shore, a plain little town famous for its Audubon refuge, heaven for birders at the height of spring migration. We are early. There are no birds. We tour the town, see an alligator in a small pond, then drive away.

At Anahuac National Wildlife Refuge, several hundred white Ibis idle in a wetland. While we watch them, hundreds of white-faced Ibis fly over. Seaside sparrows sing.

There were blue buntings the next day at the photo blind near the campground where we spent the night. We peek at them through the narrow camera ports, Mike and me and a third birder, three of us in the blind trying not to elbow each other.

Mike and I drive on to Salineño to see friends who winter there, 100 yards from a landing on the Rio Grande. They tell us of frequent gunfire at night along the shore as drug runners beach their boats. How do you tell the good guys from the bad guys in the dark? The federals, they say, shoot tracer bullets.

At Falcon Dam the river is filled with shorebirds. Caspian and royal terns squat on sandbars. Across the river, in Mexico, seven kettles of black and turkey vultures float in the late afternoon sky, details bleached from the picture by the sun. We split our last bottle of beer.

In Surfside on the west end of Galveston Island we find a motel, the Sand Castle. We rent a room. Mike tosses his bag on one of the beds. A large bug runs from beneath the pillow. This insect is one mutation away from nursing its young, but after much searching we decide it is a loner, and go to sleep.

Next morning, water from the bathroom faucet is brackish. The coffee at the convenience store we find several blocks away is brackish, too, salty coffee for 59 cents.

Ten minutes east, we stop for coffee refills. A pleasant woman who sells fishing bait and gas pours for us. Mike tells her we spent the night at a strange motel in Surfside. “Oh,” she says, “the Sand Castle.”

We drive on. At the K-2 Steakhouse we have a wonderful prime-rib dinner. Earlier that day we had read aloud a review of a book about prions, proteins that collect in your brain and give it the airy structure of a sponge, something like mad cow disease. There is a suspected beef relationship. It is not what you should be reading in Texas.

On our way out of the state we visit Hagerman National Wildlife Refuge, filled with migrating sparrows, eight species in an hour on a cold, windy day when the birds hold tight to cover.

It also is home to dozens of oil-well workers and their debris. There is some kind of deal with the devil here, wells dotting refuge landscape, rusty pipes and fast-food wrappers the most commonly seen species.

And then we drive home.