Twenty years ago, Theodore Cross traveled 16 time zones, from New York to Moscow, Irkutsk and Yakutsk, and finally to the tundra of the Kolyma Delta, in northeastern Siberia, to catch a coveted glimpse of an Arctic bird, the Ross’s gull. Mr. Cross did spot one gull, but its nest was overtaken by a parasitic jaeger before he could return with his blind and his long telephoto lens. The trip was a failure.

Two weeks later, the unexpected happened: a Ross’s gull showed up in Baltimore. Thousands of birders converged on the spot for the rare sighting.

“They call it the bird that launched 20,000 binoculars,” Mr. Cross said.

His 344-page volume, “Waterbirds” (W. W. Norton & Company), is part visual encyclopedia, part memoir of a nearly half-century pursuit of birds. In intimate portraits of birds, like tiny sandpipers and the “flying boxcar” of a bar-tailed godwit, and in personal anecdotes of his birding adventures, Mr. Cross, 85, describes how he spent the first half of his life oblivious to birds only to become one of their most ardent photographers and advocates in the second half. Now, he writes, “the memories of them help me accept the brevity of the time that lies ahead.”