. The Canadian field-naturalist. 36 The Canadian Field-Naturalist Vol. 101 fS) LU' Q < if) 80i ZD O X I- 60-. .-© Jh ^C}- T—I—r- 1950 I9 60 YEAR Figure 3. Growth of the McConnell River Snow Goose colony. Dashed Une up to 1972 joins historic estimates of colony size. Circled numbers show sources of estimates, as follows: 1—Gavin {in Cooch 1963), 2—Cooch {in Lieff 1973), 3—Maclnnes {in Hanson et al. 1972), 4—Cooch (1963), 5—Maclnnes {in Lieff 1973), 6— Bossenmaier {in Hanson et al. 1972), and 7—von Barloewen (personal communication). Data from 1972 on (solid line, including 95% ) are from
. The Canadian field-naturalist. 36 The Canadian Field-Naturalist Vol. 101 fS) LU' Q < if) 80i ZD O X I- 60-. .-© Jh ^C}- T—I—r- 1950 I9 60 YEAR Figure 3. Growth of the McConnell River Snow Goose colony. Dashed Une up to 1972 joins historic estimates of colony size. Circled numbers show sources of estimates, as follows: 1—Gavin {in Cooch 1963), 2—Cooch {in Lieff 1973), 3—Maclnnes {in Hanson et al. 1972), 4—Cooch (1963), 5—Maclnnes {in Lieff 1973), 6— Bossenmaier {in Hanson et al. 1972), and 7—von Barloewen (personal communication). Data from 1972 on (solid line, including 95% ) are from aerial surveys (Kerbes 1975, and unpublished data). Dotted line indicates estimated size if nest densities from 1972 are applied to colony areas shown in Figure 1 (see text). improbably high, but it incorporated the whole west Hudson Bay region (Tha'anne to Maguse rivers). Kerbes (1972) found that the McConnell River colony held from 70% to 92% of that region's total nesting birds from 1973 to 1980. The estimate of 50 000 nests for 1969 shows the beginning of the rapid growth period. The historic estimate for 1971 (#7, Figure 3), however, is difficult to accept, since it seems most unlikely that the colony could have doubled from 53 000 nests in 1971 to 115 000 in 1972. Kerbes (1975) suggested that von Barloewen's estimate for 1971 underestimated the densities of the colony and the size of its northern area. The estimates based on boundaries and 1972 nest. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ottawa Field-Naturalists' Club. Ottawa, Ottawa Field-Naturalists' Club
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