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BC Conservation Data Centre: Species Summary


Gavia pacifica
Pacific Loon

 
Scientific Name: Gavia pacifica (Lawrence, 1858)
English Name: Pacific Loon
 
Classification / Taxonomy
Scientific Name - Concept Reference: American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online: http://www.aou.org/.
Classification Level: Species
Species Group: Vertebrate Animal
Species Code: B-PALO
Kingdom Phylum Class Order Family
Animalia Craniata Aves Gaviiformes Gaviidae
   
Conservation Status / Legal Designation
Global Status: G5 (Apr 2016)
Provincial Status: S4B,S3S4N (Mar 2015)
BC List: Yellow
Provincial FRPA list:   
Provincial Wildlife Act:
COSEWIC Status:
SARA Schedule:
General Status Canada: 4 - Secure (2005)
Migratory Bird Convention Act: Y
   
Ecology & Life History
General Description: See Stallcup (1994) for information on identification of North American loons.
Global Reproduction Comments: Breeding begins in early May in south, to mid-June in north. Both adults, in turn, incubate usually 2 eggs, 28-29 days. Hatching occurs in second half of July around Beaufort Sea (Johnson and Herter 1989). Young are tended by both parents, first fly at about 2 months, independent by about 3 months. Pair-bond apparently is life-long. Nest density is up to 2.6 per sq km in Alaska (Johnson and Herter 1989).
Global Ecology Comments: Occurs singly, in pairs, or small groups. In winter off California, usually solitary or in pairs. Overall breeding density on arctic coastal plain estimated at about 1 pair per 200 ha; 5 nests observed on 1 pond of 21 ha (Johnsgard 1987). Egg predation by foxes, jaegers, and gulls sometimes is significant.
Migration Characteristics:
(Global / Provincial)		 
    Nonmigrant:
    Local Migrant:
    Distant Migrant:
    Within Borders Migrant: 		N /
N /
Y /
na /
Global Migration Comments: Highly migratory (small flocks); some travel 12,000 miles/years (Oberholser 1974); others move only to coastal waters near breeding range. Main migration in California: November-early December, late April-May; in southern California, spring migration peaks sometimes between mid-April and early May (Russell and Lehman 1994). Arrives southeastern Alaska by early May, arctic coast early June (sometimes late May). Peak fall migration in arctic Alaska late August-September (Johnson and Herter 1989).
Habitats:
(Type / Subtype / Dependence) 		Lakes / Lake / Unknown
Ocean / Sheltered Waters - Marine / Unknown
Ocean / Subtidal Marine / Unknown
Other Unique Habitats / Estuary / Unknown
Stream/River / Stream/River / Unknown
Global Habitat Comments: Nonbreeding: primarily seacoasts, bays and estuaries, less frequently on lakes and rivers (AOU 1983). In winter off central California, generally stays 2-8 km offshore (see Root 1988). In spring in southern California, migrants may be attracted to cool waters near the frontal boundaries of upwelling plumes, where loon prey is attracted by concentrations of zooplankton (Russell and Lehman 1994).

Nests on lakes/ponds in tundra or taiga. Usually nests on largest pond available (0.2-21 ha in one study area); selects ponds with islands or wet grassy areas. Nests on ground in scrape or on mound of material on ground in or very near water. Prefers to nest on island or at end of point extending into water (Johnson and Herter 1989).
Food Habits: Invertivore: Adult, Immature
Piscivore: Adult, Immature
Global Food Habits Comments: Feeds on fishes as well as crustaceans, mollusks, and aquatic insects; also eats aquatic seeds and some aquatic vegetation. Small shoal fishes often important in winter. Food obtained underwater during dives usually less than 1 minute. In some areas, nesting birds feed in lakes and ponds adjacent to their nest sites; in other areas, they make regular foraging flights to nearshore marine waters (Andres 1993).
Global Phenology: Diurnal: Adult, Immature
Provincial Phenology:
(1st half of month/
2nd half of month)
Colonial Breeder: N
Length(cm)/width(cm)/Weight(g): 66/ / 1659
Elevation (m) (min / max): Global: 
Provincial: 
   
 
Distribution
Endemic: N
Global Range Comment: BREEDS: eastern Siberia from Arctic coast south to Anadyrland; Arctic coast of Alaska and Canada east to Baffin Island, south to southern Alaska, southwestern Yukon, northern Manitoba, and northwestern Quebec. WINTERS: south to Japan and along Pacific coast of North America south to Baja California and southern Sonora. In North America, areas of highest winter density include British Columbia around Vancouver Island, Monterey Bay in California, and near Point Whiteshed in Alaska (Root 1988). Casual/uncommon migrant inland in western U.S., very rare on east coast (NGS 1983).
 
Authors / Contributors
Global Information Author: HAMMERSON, G.
Last Updated: Aug 31, 1995
Provincial Information Author:
Last Updated:
   
References and Related Literature
American Ornithologists' Union (AOU). 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, Kansas. 877 pp.
American Ornithologists' Union (AOU). 1985. Thirty-fifth Supplement to the American Ornithologists' Union Check-list of North American Birds. Auk 102:680-686.
Andres, B. A. 1993. Foraging flights of Pacific, Gavia pacifica, and Red-throated, G. stellata, Loons on Alaska's Coastal Plain. Canadian Field-Naturalist 107:238-240.
Campbell, R.W., N.K. Dawe, I.McT. Cowan, J.M. Cooper, G. Kaiser, and M.C.E. McNall. 1990. The Birds of British Columbia, Vol. 1. Nonpasserines: Introduction, Loons through Waterfowl. Royal B.C. Mus. in association with Environ. Can., Can. Wildl. Serv. 514pp.
Harrison, C. 1978. A Field Guide to the Nests, Eggs and Nestlings of North American Birds. Collins, Cleveland, Ohio.
Johnsgard, P. A. 1987. Diving birds of North America. Univ. Nebraska Press, Lincoln. xii + 292 pp.
Johnson, S. R. and D. R. Herter. 1989. The Birds of the Beaufort Sea. BP Exploration (Alaska) Inc., Anchorage, Alaska. 372 pp.
McCaskie, G., et al. 1990. Notes on identifying arctic and Pacific loons in alternate plumage. Birding 22:70-73.
Oberholser, H.C. 1974. The bird life of Texas. 2 vols. Univ. of Texas Press, Austin.
Roberson, D. 1989. More on Pacific versus arctic loons. Birding 21:154-157.
Root, T. 1988. Atlas of wintering North American birds: An analysis of Christmas Bird Count data. University of Chicago Press. 336 pp.
Russell, R. W., and P. E. Lehman. 1994. Spring migration of Pacific loons through the Southern California Bight: nearshore flights, seasonal timing and distribution at sea. Condor 96:300-315.
Schulenberg, T. 1989. More on Pacific versus arctic loons. Birding 21:157-158.
Stallcup, R. 1994. Focus: loons. Point Reyes Bird Observatory, Fall 1994, pp. 6-7.
Terres, J. K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, New York.
 

Please visit the website Conservation Status Ranks for definitions of the data fields used in this summary report.

Suggested Citation:

B.C. Conservation Data Centre. 1995. Species Summary: Gavia pacifica. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Dec 5, 2025).