Whooping crane groups that included a 7-year-old adult deviated less from a migratory straight-line path between their Wisconsin breeding grounds and Florida wintering grounds, a study led by the University of Maryland found.
One-year-old birds that did not follow older birds veered, on average, 60 miles from a straight flight path, but when in a group including older birds, their average deviation was less than 40 miles, a university release reported Thursday.
Individual cranes' ability to stick to the route increased steadily each year up to about age 5, the researchers said.
Many migration studies have been done on short-lived species such as songbirds, but not on whooping cranes, which can live more than 20 years, Maryland biologist Thomas Mueller, an expert on animal migration and the study's lead scientist, said.
"Here we could look over the course of the individual animals' lifetimes and show that learning takes place over many years," he said.
The whooping crane, North America's largest bird at more than 5 feet tall, was near extinction in the 1940s, with fewer than 25 individuals.
Today about 250 wild whooping cranes summer in Canada and the northern Unites States and migrate to Texas and Florida for the winter.