A few birds at Chobar (19 September) and one near Tiger Tops (29 September) showed the extremely limited fl on the breast characteristic of this subspecies, in some individuals, reduced to only a spot in the middle of the breast.
Several of the birds on the Bagmati river near Chobar (19 September) appeared to be of this race, some of them even approaching White-browed Wagtail in appearance.
Single in a mixed feeding flock near the summit of Nagarjung Forest Park on 20 September; several birds at Phulchowki on 21 September.
No species arrived with high fat loads in spring, and generally low fat levels in autumn suggest that high-latitude passerine migrants in North America are paying most of the energetic costs of long-distance migration from resources obtained en route to their wintering grounds.
Among passerine migrants near these high-latitude breeding grounds, seasonal fat deposition strategies appear to be in response to energetic needs at the level of daily maintenance rather than to hypothesized insurance needs in spring or to the forthcoming needs of a long-distance migration in autumn.
The brief subarctic summer limits the time available for birds to complete their reproductive activities, yet the temporal requirements of high-latitude passerine migrants are not well understood.
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