First occurrences of the Glaucous-winged Gull (Larus glaucescens), and hybrids between it and the Western (L. occidentalis) and Herring Gull (L. argentatus), in Utah are documented. Sightings of 14 individuals over two winters (1984–86) may represent an inland expansion of the winter range of this species.
Fischer, David L.
"First records of the Glacuous-winged Gull in Utah,"
Great Basin Naturalist: Vol. 48
, Article 21.
Available at: http://scholarsarchive.byu.edu/gbn/vol48/iss2/21