Migration chronology of Eastern-Population

We used satellite platform transmitting transmitters (PTTs) in 1998-2000 to track spring and fall migratory movements of Tundra Swans (Cygnus columbianus columbianus ) captured at Long Point, Ontario. Migration corridors reported here corroborated those identified in previous studies using alphanumerically coded neck collars. However, PTTs provided additional information on duration of spring and fall migrations, duration of stay in different staging re - gions, time spent on breeding and wintering areas, and migration speed. Birds migrated between the Atlantic coast and northern prairies along a narrow geographic corridor through portions of the southern Great Lakes. From the northern prairies, swans followed 3 corridors to breeding areas on the west coast of Hudson Bay, central High Arctic, and Mac- kenzie River delta. While swans spent considerable time on Great Lakes (27% of spring migration) and northern prairie (40%) staging areas in spring, the northern boreal forest was an important fall staging area (48% of fall migration). Tundra Swans spent 20% of the annual cycle on wintering areas, 28% on spring staging areas, 29% on breeding areas, and 23% on fall staging areas. The long duration of migration and the fact that birds spend half their lives on staging areas underscore the importance of conserving Tundra Swan migratory habitats. Thirty-gram neck-collar-attached PTTs were more suitable than 95-g Teflon-harness-attached backpack PTTs for tracking Tundra Swans. Resume : L'utilisation d'emetteurs satellites (PTT) nous a permis de suivre les deplacements migratoires au printemps et a l'automne (1998-2000) de cygnes siffleurs (Cygnus columbianus columbianus ) captures a Long Point, Ontario. Les corridors de migration que nous avons identifies confirment ceux qui ont ete reconnus dans des etudes anterieures a l'aide de colliers munis de codes alpha-numeriques. Cependant, les emetteurs PTT fournissent des donnees additionnel- les sur la duree des migrations de printemps et d'automne, la longueur des sejours aux differentes stations de rallie- ment, le temps passe sur les sites de reproduction et d'hivernage, ainsi que la vitesse de migration. Les oiseaux se