In 1935 Austrian zoologist Konrad Lorenz published a ground-breaking paper describing how goslings that he raised came to regard him as, in essence, their “parent”. Further work on this process, soon to be known as imprinting, led to the founding of the science of ethology, the study of animal behavior.
As every bird-keeper knows, chicks taken from the nest and hand-raised make the best pets. Such birds are said to be imprinted upon people, and they relate very well to us. However, there are some other uses for and sides to imprinting. Today I’d like to relate some of my experiences with an assortment of imprinted creatures.
I Like Mice, but….
My oddest bird story involves a great horned owl. Irresistibly cute in its efforts to threaten me, the owlet had been found in a Bronx park and was being harassed by some children (amazingly, these huge owls still survive in NYC, where they dine upon rats, muskrats, roosting pigeons and cats). I and my coworkers raised the owl, a male, and he became a favorite at classes and on visits to homes for the elderly.
When he matured, however, the owl developed the distressing habit of trying to jam a mouse into the mouth of any passing person, much as he would feed a potential mate under more usual circumstances. Interestingly, the owl never tried to stuff the mouse into one’s ear…he knew what a mouth was, even though the objects of his affection lacked a hooked beak (or any beak!).
Foster Parents
The owl showed no interest in members of his own species, which brings me to a major problem where imprinted endangered species are concerned. In zoo based conservation programs, we sometimes pull the eggs of endangered birds so as to stimulate the female to lay a second clutch. The pulled eggs are often put under a brooding “foster mother” of a related species, and the chicks therefore become imprinted on bird species other than their own. This has worked well for peregrine falcons fostered beneath prairie falcon hens, and for Mauritius pink pigeons, which are fostered under ring doves.
However, rare finches raised by zebra or society finches often pick up the songs of their foster parents, and prefer the foster species over their own species as mates. As you can imagine, this seriously hampers efforts to increase the population of the endangered birds.
Further Reading
The future of the magnificent pink pigeon was first championed by conservation legend Gerard Durrell. Read more at http://www.durrell.org/Animals/Birds/Mauritius-Pink-Pigeon/.