To estimate age (days old) of Japanese Marsh Warbler Locustella pryeri nestlings, I recorded daily developmental patterns (e.g., pin-feather eruption and eye opening) for 64 nestlings from 14 nests, from hatching to fledging, in Hotoke-numa wetland during the breeding season in 2008 and 2009. These patterns were age-specific, and can be used for estimation of nestling age. In addition, I measured tarsus and natural wing lengths of nestlings and weighed them from 1 to 8 days after hatching. These traits had large variance, and thus were not age-specific; a logistic model might account for the growth patterns of these traits.

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We report molting of the Crossbill Loxia curvirostra japonica in the Shimokita population of Aomori Prefecture. Molting frequently occurred at the outer four primaries, the inner third plumage in tertiaries, and the outermost greater covert in 39 recorded adult birds in November. A Crossbill, which was captured in September and recaptured in November in 2011, had replaced feathers at the outer four primaries and at the outermost tertiary. Based on 58 birds which were recorded molting score, we estimated their molting schedule, sequence and position. They were suggested that having non-typical molting pattern and partially molting. Male body plumage was yellowish or reddish regardless of age. Therefore, we must be careful when using age and sex determination of Crossbills without development of an incubation patch or cloaca.

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An adult Pheasant-tailed Jacana Hydrophasianus chirurgus was found in Niigata Prefecture on November 17, 2010. This is the first time this species has been observed in Niigata. The bird was deceased when we found it.

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