39 



ROCK SANDPIPER (Calidris ptiloonemis; choice 39', pg. 49) is some- 

 what smaller than a robin and has a slender, tapered bill with a yellowish 

 base, and dull yellowish to greenish legs. In breeding plumage back 

 feathers are black with rufous, ochre, and white edges; the white under 

 surface has a large dusky patch on the lower breast and belly. In winter 

 and juvenal plumage, birds are medium gray dorsal ly. They have heavy 

 gray streaking on the neck and breast, but the belly is white. Rock 

 Sandpipers may be found in Alaska year round and farther south from 

 October to May. 



DUNLIN (Calidris alp-ina; choice 39, pg. 49) is between a sparrow and 

 a robin in size. Its legs are black, as is its long, slightly downcurved, 

 tapered bill. In breeding plumage (April to September) they have much 

 rufous coloration dorsally and a black belly patch. Winter plumage is 

 gray-brown dorsally and white ventrally. In juvenal plumage (July to 

 September) dorsal feathering is edged with rufous; the throat and breast 

 have diffuse streaking. Dunlins occur in Alaska from April to October 

 and farther south from September to May. 



CURLEW SANDPIPER (Calidris ferruginea; choice 41, pg. 49 ) is a 

 white-rumped bird between a robin and sparrow in size. The black bill is 

 fairly long and curved downwards (sometimes only slightly) at the tip 

 (Plate 24-8). Legs are black. In breeding plumage the ventral feathering 

 is brick red, a color lacking in winter and juvenal plumages. Curlew 

 Sandpipers are rare on the west coast; they are most likely to be found 

 between April and September. 



SKUAS AND JAEGERS (STERCORARIIDAE) 



This group is closely related to gulls. Once a specimen has been identified 

 as a skua or jaeger the key will suffice in identifying it to species. 

 Without doubt, though, one's initial inclination will be to almost always 

 consider a specimen from this group to be a gull in immature plumage. 

 Owing to the brown coloration and general shape such a choice is not 

 surprising. Closer inspection will reveal long sickle-shaped and sharp 

 claws (Plate 35-1), reticulate rather than -scutel late scales on the legs 

 (Fig. 13), white shafts and bases to the otherwise dark outer primaries, 

 and a saddle-shaped plate on the upper bill (Plate 25). None of these 

 characters are possessed by gulls. The jet black or black and blue feet 

 and legs, in conjunction with the mostly dark plumage, is a combination 

 that should arouse one's suspicions that the specimen is not a gull. 

 Since most specimens found on beaches are immatures or are molting, do not 

 rely on length of the central two tail feathers, a feature often discussed 

 in field guides, to confirm species identification. None of these species 

 are very abundant. Any specimens south of Alaska should be saved. 



