It's tricky for us mere humans to know exactly how cranes raise and educate their young. The young are precocial (the chicks leave the nest entirely soon after hatching), and we can't possibly follow wild families with a video cam, so we have no way of closely observing interactions between parents and young cranes in the wild. We can observe how cranes raise their young in captive situations, but it's much harder to draw conclusions about how this compares with wild situations for a few reasons:
- Parent cranes rearing young in captivity were themselves raised in captivity, either by people in "crane suits" or by cranes that themselves were raised by people in crane suits. Do young cranes learn critical lessons from wild parents that captive-reared adults simply don't know about? We don't know!
- Wild cranes remain constantly with their parents for almost a full year, at least one parent present the the chick(s) every minute of every day and night. Do cranes in captivity need this model to remain steadily with their own eggs, and then chicks?
- Wild adult cranes react to various situations with calls and behaviors, and are exposed to a much wider range of social situations and dangers in the wild than in captivity. Their young learn from them how to react to the same situations. We've only observed these behaviors in wild cranes anecdotally, so we can't understand the entire range of these behaviors, or how to mimic them in captive-reared birds. How essential for young cranes is remaining every minute of every day with parents, both in terms of their own long-term survival and in terms of their ability to raise young successfully?
- Wild cranes in a wild natural setting feed on a wide variety of foods. Foraging parents show their young where to forage for which foods. Captive-reared birds are exposed to fewer microhabitats for foraging. Does this limit the number of microhabitats where they lead their own young after release?
- Captive-reared birds aren't exposed to pest insects at anywhere near the rates that wild birds deal with. In particular, the Necedah NWR birds have had a horrible time dealing with Black flies during the nesting season. How do the truly wild cranes in Canada deal with Black flies and other insect pests? Do they have strategies to teach their young to avoid nesting where flies could pose a problem?
Our Successes
We've been studying wild and captive Whooping Cranes for many decades, and out of all this research came enormous strides toward saving the species, raising the number of Whooping Cranes in the world from a mere 14 adults in 1938 to the many we have today. This success is directly due to field research, veterinary and avicultural expertise, and behavioral studies. We've also had wonderful success releasing captive-reared birds to the wild.
Next Steps
Now the next benchmark in this long-term experiment will be reached when significant numbers of birds in these programs are successfully raising their own young. We've come so far already, but we have a long way to go—and much to learn—to make a wild-nesting Whooping Crane population in Wisconsin a reality. The work continues!
Photo Vickie Henderson
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