Thayer's Gull (thayeri)
(last update: January 22, 2013)
Table 1. Definitions of Iceland gull taxa mainly from adult upper surface wingtip melanism based on a variety of sources.
Belongs to the paper:
Hybridization and changes in the distribution of Iceland gulls
(Larus glaucoides/kumlieni/thayeri),
by D. N. Weir, A.C. Kitchener and R. Y. McGowan,
IN: J. Zool., Lond.(2000) 252, 517-530.
| Features | thayeri |
kumlieni |
glaucoides |
| Number of primaries with melanism | (3)4-6 |
1-5 |
0 |
| Melanism scores P 10-6 | 2.0-4.5 |
0.2-2.5 |
0 |
| Iris colour of breeding adults | dark
(purple/brown speckling) |
intermediate |
clear greyish-yellow |
Sources: Dwight, 1906, 1917, 1925; Salomonsen, 1950; MacPherson, 1961; FjeldsaÊ & Jensen, 1985; Godfrey, 1986; Ingolfsson, 1967, 1970; Snell, 1989, 1991a, b; additional Iceland gull data by us from specimens, after Snell (1991b).