Abstract
L ooking back at my life-long career in zoo work, I recall the fundamental changes ethology brought about in the breeding of zoo animals. In the 1960s the new insights into animal behavior gave us tools to breed many species only sporadically reproduced in captivity before. Handraising of offspring became common practice to save the young which often were abandoned or even killed by the parents due to outdated, unsuitable environments. The knowledge of how to breed species biologically correctly suddenly outpaced the ability for zoos to rebuild their facilities.
In the interim, this time period generated significant new data and experience in the technology of rearing offspring without their natural parents. Soon however, the focus shifted from hand-rearing to parent-rearing, and with species-designed environments this gained considerable grounds. The driving force to this notion was the growing awareness of and reservation against taking specimens from the wild, in light of the species extinction crisis looming on the horizon.
Parent-rearing produced progeny imprinted on their parents rather than human foster parents, which in turn assures that the young will interact with their own kin properly as they mature, mate, and reproduce. This is the foundation of captive breeding
programs of wild animals from an ethological perspective.
To overcome the profound imprinting effects in birds, chicks were raised with puppets replicating the parents image and taped vocalization of their natural parents. I need not to mention the astonishing work done in the crane breeding program, California Condor recovery work, and many others. Although, I am unaware of puppet raising Pekin Robins, I submit this case study by giving full credit to the great mentors from which I got the inspiration. What may be new, is to apply this technique to a less threatened softbill bird species much lower on the scale of things. But then, you can impose innovation from the bottom up as well as from the top down.
Now retired, I decided in spring of 1999 to add a pair of Pekin Robins to my small courtyard type Oriental garden. I anticipated obtaining these by making a few phone calls. Not so. The species had been placed on CITES September 18 1997 and zoological suppliers no longer had easy access to Pekin Robins.
It became apparent that effectively only male birds had been imported from Asia, not because of Western market interest, but due to the market demand in their home range, where the birds are captured for singing companion birds. Hence females were hard to
The body is made out of a solid piece of easily carved wood such as cedar or bass wood. A hole is drilled in the upper fore head to glue in the fixed upper mandible (a).
The lower mandible is part of the dog leg shaped lever (b).
Both mandibles are shaped out of a 1/4 inch thick piece of hard wood.
The lever pocket (c) is drilled with a 3/8 inch drill and cleaned out with a small bladed knife or chip knife to allow for enough room to operate the lever. A pivoting pin hole (d) is drilled into the body and lever to receive a finishing nail to align the parts.
A groove is cut around the middle of the body (e) to hold a rubber band in position to pass under the end of the lever, as seen in cross section 3A. The lever has a small notch to keep the rubber band in place (f). The band must be under tension to bring the lever back up in "beak-open position" when the pressure is released by raising the finger, as seen in cross section 3B. Correspondingly the beak is closed by depressing the lever in the lever pocket on the back of the body.
The puppet is painted with acrylic paint and finished with Varathane water based finish to allow for frequent cleaning. Black glass pins serve as eyes.
come by.
Eventually a female was located and breeding the species became a keen, personal goal. The original pair produced two females in 1999 and subsequent breeding in 2000 added 6 female chicks to the program, now in place to breed the species in a budding circle of breeders at the West coast of British Columbia, Canada. -c • •
The decision to handrear a clutch of Pekin Robins rests with the need to produce captive born birds and females in particular for the moment. In addition, the parents, a pair I am holding on loan, had not reproduced successfully prior to this and progeny with unrelated genes had to be saved.
On July 8, 2000 the loaned pair of Pekin Robins abandoned their nest with two 5-day old chicks. A cat had been seen on an adjacent aviary roof at nights which presumably caused the abandonment. The chicks were cold and immobile when they were removed from the nest in the early morning. A thermometer placed next to their bodies read 25 degrees Celsius [75° F.]. Each weighed 13 grams. It always amazes us how fast the chicks gain body mass and weight when we recognize that a Pekin Robin weighs less than 2 grams at hatching time.