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â€" We report the study of parental care of Wood Thrush ( Hylocichla mustelina) fledglings from nest-leaving to independence. From 1993 to 1995, we captured, radio-tagged, and monitored the movements and behavior of 23 fledglings and their parents from 12 broods at the U.S. Marine Corps Base, Quantico, Virginia. For pairs that subsequently renested (n = 5), the family group of male, female, and fledglings, remained within 62 (±5 SE) m of the first nest after fledging. During the period of post-fledging parental care, mean maximum distance between parents was 70 (±14) m. Females attended the young 13 (±1.3) days before initiating the incubation of a second clutch. Males continued attending the fledglings for 6 (±0.7) more days until the young achieved independence and dispersed (28-36 days post-hatching). In final clutches (n = 7), brood care was divided between the parents, and the position of the fledglings relative to the nest depended on the parents’ choice of molting site (in the nesting area or elsewhere). Division of the brood by the parents has been thought to be a strategy to reduce predation and increase foraging efficiency. However, in the Wood Thrush and other species, joint attendance of initial broods, but division of final broods, suggest that other factors could be important for the parents' decision of whether or not to split the brood.

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We monitored 42 radio-tagged, fledgling Wood Thrushes (Hylocichla mustelina) to investigate movement and habitat use during the postfledging period. Fledglings' mean (? SE) age at dispersal from the natal sites was 32.5 5 0.6 days post hatching. First dispersal sites were located 1.5 ? 0.3 km from the natal site. All young joined flocks of juveniles, except three birds that remained solitary. Sixteen birds stayed at the first dispersal site until departure on migration, whereas nine visited additional dispersal sites. On 40 occasions, 15 fledglings moved up to 6 km from their dispersal sites. Before late August, 96.7% of fledglings' locations occurred in: (1) second growth scrub/deciduous sapling sites located along forest borders and abandoned farms (59.4%), (2) gypsy moth (Lymantria dispar) damaged deciduous forest (24.4%) and (3) Virginia pine (Pinus virginianus) forest with heavy deciduous understory (12.8%). Fruiting trees and shrubs used as food sources by juveniles fruit earlier in these habitats. After late August, an increased number of fledgling locations (14.1%) occurred in mature deciduous or mixed forest, possibly tracking the later fruiting cycles of understory plants in these habitats. Twenty-four of 33 fledglings left the study area in September. Mean age at departure was 81 ? 5 days post hatching. We suggest that postfledging movements in Wood Thrushes are keyed by the availability of food resources and the presence of conspecifics, although other factors may play a role. We conclude that successful conservation of migratory species requires protection of habitats used during the postfledging period as well as those used during the nesting portion of the life cycle.

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