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â€" We trapped more than 23,000 migrating raptors at Cedar Grove, Wisconsin during the autumns of 1953â€"1996, permitting accurate identification of age and sex. Adults migrated significantly later than juveniles in 8 of 10 species, and males migrated later than females in 7 species. We suggest that it is adaptive for adults and males to remain on breeding territories as long as possible. Adult Peregrine Falcons ( Falco peregrinus ) migrated before juveniles. There was no age difference in migration of Rough-legged Hawks ( Buteo lagopus). Both species breed in the Arctic where the brief breeding season requires that adults leave as soon as possible so adults might then migrate more rapidly than juveniles. We compare our results with those of 16 other studies. Juveniles migrated significantly later than adults in 8 of 13 species at Falsterbo in southern Sweden (Kjellen 1992). Falsterbo is more than 12° latitude (1300 km) north of Cedar Grove and the breeding range of most of the species occurring there extends north of the Arctic Circle, where birds suffer from the same abbreviated breeding seasons as do the Peregrine Falcon and Rough-legged Hawk in North America. Adult females migrated after adult males in the two large species of Accipiter ; this may be because the females, not the males, establish and maintain territory in these species.

A new species in the morphologically conservative Tylototriton asperrimus group is described from Khammouan Province, Laos. Molecular phylogenetic analysis of mitochondrial DNA confirms its placement in the T. asperrimus group. Tylototriton notialis sp. nov. is diagnosable in mitochondrial DNA, nuclear DNA, and morphology from its congeners. The new species represents the first record of the genus from Laos, and is the southernmost known member of the T. asperrimus group.

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