May 20, 2008Comments Off on European Starlings, Sturnus vulgaris, Can Determine When People are Watching – and React Accordingly4390 Views
Researchers at the University of Bristol determined this month (May, 2008) that starlings and other birds moved away from feeders if watched by people, but continued feeding if the observers remained just as close to the feeders, but turned their eyes away.
Interesting….but I think bird keepers have known this to be true for quite some time. Most of us learned early on that parrots focus on our eyes when watching us, and that the best way to sneak up on a bird that is reluctant to return to its cage is to observe it by quick, side-wise glances. This is a good point to keep in mind when watching newly acquired finches and other shy pets.
In fact, a key to being able to get a good look at the birds I worked with in large zoo exhibits was to avoid a direct stare. Birds feeding calmly not far from me would immediately fly off if I shifted my glance, even if the rest of my body remained immobile. I had first learned this lesson in the wonderful book Hand Taming Wild Birds at the Feeder, by Alfred G. Martin (Bond Wheelwright Co., 1963), and was subsequently able to induce a variety of birds to feed from my hand.
I have a bit of evidence that birds “know” the meaning of other human facial features as well. I once helped to raise a barn owl, Tyto alba, that had been found on a Bronx street (yes, a surprising number of birds do live there!). The bird imprinted on people (came to view us as its “parents”), which suited it well for us in educational programs. As hand-raised birds will do, this male owl sought a human “mate” when it matured. In typical barn owl fashion, it would bring any nearby keeper a mouse – perching on our shoulders and trying to stuff its lovely nuptial gift into our mouths! Never once did the owl try an ear or eye – it seemed to be able to make, in its brain, the quite large transition from bird beak to human mouth.
To read the first part of this article, click here.
In reproductive biology as well, the palm cockatoo breaks with its close relatives. The male’s breeding display is the group’s most complex – flying high above the ground towards his mate, he raises his spectacular crest, deepens his cheek patch color, and calls loudly. They are the only cockatoos to build stick nests within their nest cavities – perhaps as a precaution against flooding – and their young are unique in hatching without down and in having such a long (to 160 days) nestling period. Even after all that time, young palm cockatoos fly poorly upon leaving the nest and are fed by their parents for an additional 6 weeks.
Strictly protected by the governments of New Guinea and Australia (and listed on Appendix I of CITES, The Committee on International Trade in Endangered Species), palm cockatoos were relatively unknown in American aviculture until quite recently. In fact, zoos here did not pay much attention to Psittacines in general – intelligent and gregarious, they need lots of room, stimulation and appropriate social groups and thus are difficult to provide for. After observing flocks of military macaws, Asa militaris, and other species, in the wild, I came to regard parrots and their relatives, in terms of their captive needs, as the “primates of the bird world”. Those of you who keep them as pets are no doubt familiar with their curiosity, and are fortunate in having a wide range of helpful products from which to choose when looking to keep them happy.
In 1983 the US Fish and Wildlife Service confiscated a large group of palm cockatoos, and placed them with various zoos and qualified private individuals. I was working in the Bronx Zoo’s bird department at the time, and learned that I would be assisting in the hand rearing of two chicks. Given the rarity of this species in captivity, I was excited by the opportunity to perhaps contribute to our understanding of its captive husbandry. The group eventually did quite well, and gave rise to a good percentage of the individuals in this country today.
The two chicks were at first fed (via syringe) around the clock, and thus required attention at all hours of the night. This quickly gave rise to their names – “OT” and “MOT”, signifying “Overtime” and “More Overtime”! Their helplessness (and the fattened pay checks they engendered) endeared the birds to their keepers. With barely any down feathers, they were at first kept at quite warm temperatures (92 F or so) in an incubator. Feather growth increased from age 3 weeks, when the temperature was reduced to 85F, and was complete when the birds were approximately 3 months old. The chicks’ face-patch color was variable even during their first weeks of life, although I cannot say what the changes meant. In common with most healthy nestlings, their feeding reaction was quite strong and, oddly, accompanied by much head bobbing.
In those days, formulas for hand-rearing cockatoos were not standardized, and the various zoos involved in the project experimented quite a bit. A dilute mix of Pedialite, monkey chow, baby cereal and fruit was common to most diets, and worked well (although not without some digestive upset). Today, both zoos and hobbyists have a number of fine products available, and hand-rearing success stories are more common. The chicks began pecking at solid food at 2 ½ – 3 months of age – I later learned that the timing of this milestones varies greatly among palm cockatoo chicks. Supplemental formula was given until the birds were approximately 4 months old and gaining weight consistently. They were later transferred to the World of Birds building, where their exhibit remains a major attraction.
I am happy to say that we learned quite a bit that has been of use to other bird keepers, hobbyists and their charges, and helped establish this magnificent species soundly in North American zoos and private collections.
Cockatoos and parrots are at once fascinating and challenging as pets – please share your own stories and forward any questions you might have.
You can see a video of a palm cockatoo at the Bronx Zoo (perhaps OT or MOT) below:
More information about the group of confiscated birds I referred to, and concerning parrot conservation in general, is available at: