Abstract
Data on density, previous population levels, presence of occasional and regular flocks and direction of bird movement, collected during early and late winters for different broad localities suggest that Houbara gradually moves through diffused routes into and out of Balochistan (Pakistan), keeping a predominantly north-south direction during autumn and south-north direction during spring. Th.se movements are largely controlled by temperature, but latitude gradient is more important in forcing autumn movements, and spring movements are more influenced by altitudes. Steep rocky hills act as strong barriers, while feeding grounds and human disturbance have little role in controlling such movements. Evidences suggest that bird movements are more controlled by external environmental factors than the internal biological clock of the species. The species depend more on walking for migratory movements, though may resort to different stretches of low flights. Overlapping of breeding. and non-breeding ranges of the race suggest that mass scale movement occurring during autumn and spring does not strictly fall sunder the definition of migration, and can be regarded as population adjustMents along its distribution range during summer and winter to fight unfavourable temperatures and associated biotic or abiotic factors.
AFSAR MIAN . (1997) ON BIOLOGY OF HOUBARA BUSTARD (CHLAMYDOTIS UNDULATA MACQUEENII) IN BALOCHISTAN, PAKISTAN: A PRELIMINARY STUDY ON MIGRATION , Punjab University Journal of Zoology, Volume 12, Issue 1.
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