Anne,
At 11:15 AM 9/13/97 -0700, you wrote:
>Could the bird have
>been eating a diet low in roughage and need the materials mentioned for
>healthy pellet formation?
>Regards, Anne Green
The behaviour of the hobby sounds very unusual to me. I think I can
remember reading in past issues of the EMU of parrots or cockatoos chewing
at burnt wood / charcoal. They don't need to for normal digestion and
maybe such activity is associated with foraging for insect larvae or green
shoots. Birds (even most graniverous ones) don't need to ingest dirt or
pebbles for normal digestion. Maybe the hobby had some oral or oesohageal
lesions (eg canker) which was causing irritation... Nevertheless, it
sounds from its reluctance to depart, that there was significant intention
to the activity. Alternatively, it had been raised by swallows and was in
the process of building its first nest!
Shane Raidal
>> Chris says:
>> At 5pm on 29th July 1997, five hundred metres along the
road to Willie
>> Creek off the Cape Leveque road on the Dampier Peninsula, four of us
>> witnessed an Australian Hobby (Falco longipennis) eating dirt, small stones
>> and charred wood fragments.
>> The Hobby was seen initially at a distance on the road and I stopped the
>> car for a close view. Driving slowly forward I got within 1.5 metres of
>> the bird before it flew, but only a further 8 metres from our vehicle. The
>> bird was reluctant to fly and we initially wondered if it was injured or
>> sick.
>> We drove forward slowly and got within about 6 metres of the bird. Using
>> 8x40 and 10x50 binoculars, we watched as it waddled awkwardly around the
>> Pindan dirt road and picked up small stones and pieces of charred wood and
>> swallowed them.
>> The bird also scraped soil from the road using its lower
>> mandible and ate this as well. On at least fifteen different occasions the
>> bird seemed to swallow its "prey" and appeared to be using sight to
>> identify and select items to eat. The Hobby moved around on the road in
>> making its selection and was more reminiscent of a plover than a bird of
>> prey.
>> After its initial reluctance to fly and after 15 minutes of close views of
>> this behaviour the bird suddenly flew off strongly into the woodland. The
>> bird was totally undisturbed by our presence and only seemed to leave after
>> it had eaten its fill.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Shane Raidal BVSc PhD MACVSc
Lecturer in Veterinary Pathology
Department of Veterinary Biology and Biomedical Sciences
Murdoch University phone: +61 8 9360 2418
Perth,WA, 6150 fax: +61 8 9310 4144
Australia
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