16 



YELLOW-BILLED LOON (Gavia adamsii; choice 3', pg. 24) is far less 

 abundant than any of the other loons. One might find an occasional 

 individual along Bering Sea and western Alaskan coasts during late spring 

 or fall and along southeast Alaskan and British Columbian coasts during 

 fall, winter, and early spring. It would be unusual to find one from 

 Washington to central California during the latter period, and even more 

 so farther south; but as they do occur in these regions, the possibility 

 should be considered whenever a very large loon with a light-colored bill 

 is found. 



This species is very similar in size, color, and shape to the Common 

 Loon, except for the head and especially the bill (see discussion under 

 Common Loon; Plate 1). Do not attempt to distinguish it from the Common 

 Loon if the specimen is headless. Identification should be verified 

 through consultation with a person very knowledgeable in loon identification, 



ARCTIC LOON (Gavia arctica) and RED-THROATED LOON (G. stellata; 

 choices 2 and 2', pg. 24) occur along Bering Sea coasts during summer and 

 from western Alaska south to southern Baja California during fall, 

 winter, and spring. Occasional specimens would be encountered in the 

 latter regions during summer. 



Among the larger seabirds, they are nonetheless much smaller than the 

 previous two loon species and range in weight from 1.5 to 2.5 kg (up to 

 5.75 Ibs.). In addition to smaller size, they are distinguishable from 

 the two other loons by their much smaller, thinner bills and different 

 back coloration. In winter plumage the upper parts of Arctic Loons are 

 largely dark except for a few scapular feathers each of which have a pair 

 of white spots. Red-throated Loons are similar except for much more 

 spotting all over. 



GREBES (PODICIPEDIDAE) 



Grebes, like the previous group, occur in coastal waters of western North 

 America mainly during the fall, winter and early spring. During the 

 summer, nesting takes place on fresh water lakes. They are characterized 

 by long necks, streamlined tail-less bodies, very flat tarsi with dis- 

 tinctively lobed feet, white secondaries (except in the largely non-marine 

 Pied-billed Grebe), curved primaries (making the outer wing "cupped"), 

 and their very tight, compact body feathering. Only during late spring 

 would specimens in breeding plumage be found in coastal areas. 



WESTERN GREBE (Aechmophorus occidentalism choices 3-4', pg. 25) is 

 an abundant species occurring from southeast Alaska to southern Baja 

 California during the non-breeding period. A specimen encountered on 

 the coast during summer is not unheard of but is noteworthy. 



The large size and long, stiletto-shaped bill (Plate 2-5,6) dis- 

 tinguishes most specimens from other grebe species. Headless specimens 

 should be separated from Red-necked Grebe with great care. 



