National Geographic : 1984 Jul
ULIDING ON SILENT WINGS, a mother owl returns to her nest (right). Great grays do not migrate, but they do become nomads if their food supply runs thin. David against Goliath (below left), a robin bores in on an owl perched too close to the robin's nest. The robin flew right into the owl's body, but the owl didn't budge. When the robin attacked again and again, the owl finally got the message and moved away. Great grays have few predators; the birds' worst enemy is man, who encroaches on their habitat for lumber and clears it for farmland. Traps, guns, and traffic are also hazards: Over a period of two and a half months Dr. Nero recovered the remains of 50 great grays struck by automobiles and trucks on a 35-mile stretch of Highway 1 east of Winnipeg. In a clear-cut area of Island Park (below right) a male perches on a snag, listening for gophers. There are lots of them there, but very few perches for listening posts. I followed this 134 bird for two hours, and he didn't make a single kill.