Learning to be wild
Wanna see some movies?
Crane chicks being fed.
Crane chicks sparring with each other.
(2.8MB, QuickTime).
Cranes following their keeper.
(1.2MB, QuickTime).
Cranes learning to fly.
(.7MB, QuickTime).
Courtesy of the International Crane Foundation and Dave Erickson.
When a flock of cranes dies out, their migration pathway dies with them, and that endangers the whole species. It's the familiar "all-the-marbles-in-one-basket" argument: Individual flocks flying a single pathway are susceptible to environmental, health and predatory threats. Indeed, a hurricane in Louisiana in 1940 helped wipe out the next-to-last flock of whooping cranes, reducing North America's largest bird to just 15 individuals migrating between Texas and Canada in 1942.
The Texas flock has since grown to 182 members, and after years of effort, a group of about 55 birds lives in central Florida, where as many as six pairs are preparing to breed. The Florida population is sedentary (sounds like us Why-Filers!) meaning it does not migrate.
Conservationists would like to establish a second migratory population, but since migration pathways are learned, a problem arises: who's going to play AAA and teach the birds where they're going? One possibility is to do some pre-release education with ultralight aircraft. Sandhill cranes (common cranes that are often used for experiments in captive breeding and reintroduction) have been taught to fly behind these snowmobile-engined, bailing-wire aircraft, which motor along at a stately 28 to 40 miles per hour. The plane would replace the parents as guides, and help establish a new, separate flyway that could help isolate whoopers from ecological or biological disaster.
Motorin' mama
On Oct. 8, 1998, Lishman and company plan to drive and fly 14 sandhills on a repeat southerly migration. (Driving will eliminate much of the hazard of flying, and Lishman expects they can learn pathway without flying the whole route.) This time, the birds were reared in strict isolation -- seeing no humans but "meeting" the planes early enough to see it as a security figure.
In essence, Lishman is trying to split hairs -- to imprint the cranes on the plane, but not on the people. It sounds crazy, but it could work, Lishman says. "You can get them to follow a radio-controlled truck if that's the only thing they know. It's the size and shape, and the noise, that they're used to." For young cranes, the ultralight becomes "a safety thing. They want to stick with whatever they are familiar with because it hasn't hurt them." See "Leader of the Flock" in the bibliography.
Did you catch The Why Files on migration?
Whoopers haven't yet migrated behind an ultralight, but the day could be approaching. In 1997, Bill Lishman, a Canadian conservationist, led a group of sandhill cranes from Ontario to South Carolina. The project proved that the cranes can be trained to follow ultralights on a long journey, but the animals were imprinted on humans and did not mate with other cranes.
Motherless megapods
Instead, megapods build mounds or burrows that capture solar or geothermal heat, or are warmed by decaying vegetation. The mounds, built from sand, dirt and vegetation, can be 13 meters in diameter and more than 2 meters high. After the parents create a mound, the female lays eggs. Then the parents depart, leaving the young to burrow out of the mound and immediately start raising themselves.
In an approach that may appeal to stressed-out human parents, the parents apparently never lift a feather to help their young, yet at mating time, genetic programming enables the young to recognize their own species.
Learning to be a parent is a big deal in the long-standing effort to restore the golden lion tamarin to Brazil's vanishing coastal forest.
As George Archibald of the International Crane Foundation observes, the "old nature-nurture dialog is a little bit different in every group." 
While cranes imprint on whatever animal they see at birth, birds in the family Megapodiidae, which live in Australia and nearby islands, know their species instinctively. Adults have nothing to do with their young after hatching. In fact, the parents -- forget about buying sneakers and paying for college -- can't even be bothered to incubate the eggs.
