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In addition to the above records, estimates were given for the Alder Flycatcher Empidonax alnorum of 48 days in Alaska and 73 days in S. Ontario at 40°42'N, and for the Yellow Warbler Dendroica petechia of 84 days in Alaska and 104 days in S. Manitoba at 50°1'N.

From Winker et al. (1992a), Benson & Winker (2001).

In addition to the above records, estimates were given for the Alder Flycatcher Empidonax alnorum of 48 days in Alaska and 73 days in S. Ontario at 40°42'N, and for the Yellow Warbler Dendroica petechia of 84 days in Alaska and 104 days in S. Manitoba at 50°1'N.

From Winker et al. (1992a), Benson & Winker (2001).

year) and the Alder Flycatcher Empidonax alnorum at only 48 days (13% of the year). In the flycatcher, the adults left immediately after breeding and the young a fortnight later, both groups postponing their moult until later in the year. Comparable estimates of residence periods for the same species at lower latitudes were longer than in Alaska (Table 14.1). In Minnesota, at 44° 55'N, 18 long-distance migrants remained for 105 days or less (compared to 91 in Alaska). Among five species that bred in both areas, the Minnesota birds stayed, on average, 22 days longer in their breeding areas than their Alaskan equivalents. The shortest periods in Minnesota of 95 days or less were shown by the Yellow-bellied Flycatcher Empidonax flaviv-entris and Least Flycatcher E. minimus, both of which left immediately after breeding (Winker et al. 1992a). This pattern of longer residence in lower latitude areas is widespread in birds, but not universal (see later).

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