Questions and Answers about the Ultralight Migration
Photo by Mark Chenoweth
Why do the cranes have to be taught to migrate?
Cranes learn the migration route from the previous generation. Chicks hatched on the nesting grounds learn to fly with their parents, following them in the fall to the wintering grounds. Their destinations and the route they use may have evolved for thousands of years but it exists only in the memories of the birds that use it. If all individuals of a species are lost from a region, the route is lost forever. Birds that are raised in captivity lack an older generation to teach them and they tend to become resident, staying the entire year in the same location.
Why use ultralights to lead the birds?
Several methods have been used in an effort to reintroduce birds in a migratory situation. Whooping crane chicks have been placed with adult sandhill cranes in a cross-fostering program. Birds have been conditioned to follow handlers in a truck and led along a predetermined route. Also, birds have been released with a similar wild species prior to migration in hopes they would follow them south. In another study, cranes were transported to a staging area and allowed to fly free. They were then recaptured and moved farther south and again released. This was repeated along the entire route in hopes the birds could connect-the-dots during the return migration. All of these methods have resulted in varying degrees of success but none have been as successful as the ultralight-led technique. It most closely replicates the natural process of a parent leading the offspring south. Ultralights are the only type of aircraft that can fly slow enough (and not stall) to enable birds to follow. Operation Migration, Inc. has conducted ten migration studies with three species of birds and worked with the Patuxent Wildlife Research Center to establish the protocol that would be used to reintroduce whooping cranes into eastern North America.
How do you train the cranes to follow the ultralight?
The process is based on the bird's natural instinct to imprint. Once hatched, the chick is attracted to the first creature that nurtures it, normally the parent. This is nature's way of ensuring the offspring stays close and is protected by the adults. The procedure we follow replaces the parent bird with the handler and so the birds imprint on the surrogate parent. Prior to hatching, a recording of the aircraft engine is played to the chicks. They are introduced to the ultralight at about seven days of age and they soon associate it with the handler. The birds are not trained to follow the aircraft; instead they are conditioned to it as an extension of the handler. After they arrive on the wintering grounds and reach the sub-adult stage, they become independent and they no longer look to the handler and aircraft for security and comfort. Unlike training, the conditioning diminishes with maturity.
Do ultralights lead the cranes back in the spring?
No. The cranes learn the migration route during the trip south. In the wild they often leave the parent birds during the course of the winter, yet still return to the summering area in the spring. Based on previous research with sandhill cranes, a closely related species, whooping cranes are expected to migrate back to Wisconsin on their own, the next spring.
What role do state wildlife agencies have in the states along the migration route?
Our state wildlife agency partners identified stakeholder concerns related to the project, proposed migration stopover locations and will help coordinate the migration with private and public landowners. Some of the migration stopover locations are located on prime state-owned wildlife lands. States have been kept fully informed of progress made by the migration team. The Whooping Crane Eastern Partnership obtained the support and approval for the sandhill crane migration study in 2000 from all the states within the NEP designation area.
Are people able to watch or view the cranes during the migration?
During migration it may be possible to see the birds from a distance when they land or take off from an overnight location. But the need to keep the cranes from imprinting on humans means that all efforts are taken to keep people out of the birds' range of vision. No one - not even project leaders or participants - would be allowed to approach the birds. The ultralight pilots take measures to ensure that they are never seen by the birds out of costume, even while they are flying. In addition, video footage and still photographs of the flights and the birds would be available to the public through the news media, on the Whooping Crane Eastern Partnership website, and on the websites of the individual organizations that are part of the Partnership. The public will also be able to track the birds' progress by visiting the WCEP website.