National Geographic : 1957 Dec
Bright Dyes Reveal Secrets of Canada Geese Dyed-in-the-egg Goslings and Grown Honkers with Neckties Help Scientists Improve the Lot of These Majestic Birds 817 BY JOHN AND FRANK CRAIGHEAD With Photographs by the Authors TWO baffled Idaho hunters brought their day's bag into a checking station one frosty November day and asked the conservation officer for an explanation. They dangled a pair of plump, grayish brown Canada geese. Around each snakelike throat was knotted a brilliant plastic necktie, one yellow, the other red. One of the hunters shoved his cap back, perplexed. "I've shot plenty of geese," he said, "but these are the first ones that came wrapped for Christmas!" In time this report reached us at the Co operative Wildlife Research Unit at Montana State University. Just the summer before, we had knotted those markers on the same geese-then two-month-old goslings. Yellow meant a "girl," red a "boy" (page 828). Colors Help Trace Goose Travels Over the past five years a score of us-in cluding Montana Fish and Game biologists and State University students-have pried into the community life of the Great Basin Canada goose (Branta canadensis mofitti) in one of the most intensive investigations this splendid waterfowl has ever undergone. By injecting vegetable dye into nearly hatched eggs, we have produced goslings col ored a startling red, green, or blue (page 821). Our files are crammed with detailed "biog raphies" of more than 1,000 goose nests, in cluding notes on the number of eggs laid in each, the number hatched, and the goslings that survived to the flying stage. These activities reflect an important new trend in bird study, a shift from research on the natural history of a species to the in timate study of a single population. Colored neckbands and dyed goslings have proved invaluable tools in following the daily, seasonal, and annual doings of goose society in a typical nesting area. They have helped tell us whether flocks are increasing, dwin dling, or just holding their own, and they have revealed vital facts and principles on which to manage wisely a magnificent, once- threatened natural resource for the enjoyment of future Americans. Rare is the human pulse that fails to quicken at the sight and memorable sound of a wedge-shaped flight of Canada honkers, foretelling spring and fall as surely as thawing snows and yellowing leaves. Generations of hunters have held this heavy-bodied, boldly marked fowl in highest esteem. Traits of Branta canadensis cannot help but warm even the coldest scientific inquiry. Parents display a remarkable concern toward their young-or even toward those of other geese, as my brother Frank and I saw demon strated one spring on the upper Snake River of Wyoming. Half a dozen times our looming yellow raft frightened hours-old goslings out of their nests into the Snake's fast-moving waters. Oddly, but characteristically, a gosling separated from its broodmates would "adopt" the raft and faithfully follow us for miles. One, trying to keep contact with the rub ber boat, bobbed valiantly alongside through surging currents. At times it disappeared The Authors National Geographic members first met John and Frank Craighead, twin naturalists, as youthful fal coners in "Adventures with Birds of Prey," July, 1937. An Indian youth of royal blood read the article and invited the authors to visit him; their experiences were described in "Life with an Indian Prince," February, 1942. As Naval officers in World War II the Craigheads organized the Navy Survival Land Training Pro gram. From their remarkable experiment in emer gency subsistence among the Kwajalein islands came "We Survive on a Pacific Atoll," January, 1948. Earning doctorates at the University of Michigan, the brothers next wrote of their adventures seeking rare alpine flowers amid Wyoming's peaks in "Cloud Gardens in the Tetons," June, 1948, and described their animal studies in the same region in "Wildlife Adventuring in Jackson Hole," January, 1956. Now 41 and each the father of three children, Frank is a wildlife biologist for the U. S. Forest Service, and John heads the U. S. Fish and Wildlife Service's Cooperative Wildlife Research Unit at Mon tana State University, Missoula.