Crows Corvus orru, ubiquitous in suburban Brisbane, now accept we hominids
as harmless, though they keep at a greater distance than say magpies. On a
recent early morning walk (5.30 am), I watched a crow foraging in a heap
of leaf and bark litter in the gutter opposite me.
It tossed aside a piece of bark, rummaged among the leaves and picked up a
small white object and placed it on the concrete kerbing. It placed a
second one beside the first then picked up both, flew about 4 metres to a
small garden bed around an ornamental shrub on the footpath, and placed
them on the ground. The crow excavated a small hole in the heaped up
grass-clippings and soil of the bed, inserted its treasures and carefully
covered them over. It picked up another small object from beside the bed
and placed it on top. The bird's behaviour was similar to that of a dog
burying a bone ... allowing for the difference in technique necessitated by
beak instead of paws in the excavation.
The crow then flew to the top of a power pole some 30 metres away and
stayed there. I examined the garden bed. I could discern no sign of the
crow's activities and could not identify any particular object as the one
placed on top, which I assume was simply camouflage. However, as I had
carefully noted where the crow had buried the objects I was able
immediately to unearth them: two pieces of broken hard plastic, each about
50 x 15 mm and a few mm thick, which I replaced and covered over again.
Without binoculars, I was unable to determine whether the crow had dark or
light eyes.
Is this sort of Corvid behaviour discussed in the literature? Or has it
been, on this list? (I subscribed only recently.) Any comments?
Syd Curtis (at Hawthorne in Brisbane, 04.11.97)
H Syd Curtis
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