Birds of Costa Rica (Dale Dyer, Steve N. G. Howell)

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In addition to the Cocos Island breeding seabirds shown opposite, Red-footed Booby (p. 48), Brewster’s

Brown Booby (p. 46), Sooty Tern (p. 58), and Common Brown Noddy (p. 58) also breed on the island.

Adventurous birders making the trip out to Cocos can also expect to see various other oceanic birds

on the transit to/from the island. As well as species shown on the main plates (pp. 40–48), other offshore

possibilities include Darwin’s [Band-rumped] Storm Petrel, Galapagos [Wedge-rumped] Storm Petrel,

Markham’s Storm Petrel, Leach’s Storm Petrel, and Swallow-tailed Gull.

GREAT FRIGATEBIRD Fregata minor 82–100cm, WS 190–225cm. Local breeder on Cocos I., where

much commoner than Magnificent Frigatebird, which is a scarce nonbreeding visitor. Juv. and imm. have

variable rusty on head, rounded white belly patch; adult female has gray throat; adult male has pale axillar

scallops, pale upperwing bar, green sheen to back. Cf. Magnificent Frigatebird (p. 44). Ranges widely at

sea. (Tropical Oceans.)

PACIFIC BLACK NODDY Anous minutus 31–34cm. Common seasonal breeding species on Cocos

Island, ranging over adjacent waters. Smaller and darker than Common Brown Noddy (p. 58) with much

finer bill, more contrasting white cap. Juv. also has contrasting white cap vs. reduced whitish forehead

patch or narrow bridle of juv. Common Brown. (Tropical Pacific.)

INDO-PACIFIC WHITE NODDY Gygis [alba] candida 32–34cm. Common breeding species on Cocos

Island, mainly Mar–Sep, ranging over adjacent and offshore waters. Unmistakable, ethereal white tern

that nests in trees, laying its single egg in a slight notch on an open branch, or in a fork. Juv. has variable

cinnamon barring and tinge to plumage. (Tropical Indian and Pacific Oceans.)

Figure 28. The lushly forested slopes of Cocos Island rise steeply from sunny tropical Pacific waters;