Boobies and gannets are large seabirds with characteristic long, pointed, thick-based bills and long wedgeshaped tails. Flight is strong and direct but often interspersed with glides. Some species often form large flocks. Capture prey with spectacular plunge-dives. Take several years to reach maturity; plumages intermediate between juvenile and adult frequently are encountered. Species on this plate are rare to uncommon in Peru, and are associated with warm ocean waters.
DETAILED ITINERARY - AMAZON BIRDS
Bird Peru Jungle:
NAZCA BOOBY Sula granti 81–92 cm (32–36 in); ws 152 cm (60 in) Breeds in small (but increasing?) numbers on Islas Lobos de Tierra and Lobos de Afuera; rare but probably regular elsewhere at sea off northwest coast. Very similar to Masked Booby in all plumages, but usually can be distinguished by bill color; see Masked for distinguishing field characters. Co, E
MASKED BOOBY Sula dactylatra * 81–92 cm (32–36 in); ws 152 cm (60 in) Status in Peru not clear, due to confusion with similar Nazca Booby; apparently a rare but regular 1 visitor to Peruvian waters, far offshore, north at least to Lambayeque. Peruvian birds presumably originate from Chilean breeding colonies. Adults of both Masked and Nazca strikingly white with black remiges (including tertials) and rectrices; some Nazca have white central rectrices, but tail always all-black in Masked. Both species proceed through a complex series of plumages. With good views, bill color separates the two species except as juveniles (when both have all-gray bills). Bill color brightens as bird matures; color at base of bill is most important for identification. Bill of adult and subadult Masked is yellow (tip may be orange); bill of Nazca is bright orange to pink (tip may be yellow). Juveniles of both species have brown upperparts and hood; this plumage superficially is similar to that of adult female Brown Booby, but hood is less extensive (white of belly extends farther forward up neck in Masked and Nazca) and usually is not cut straight across breast (instead, white intrudes up the throat in inverted “V” rather than being confined to lower breast and belly); also, juvenile Masked and Nazca have dark bills (relatively pale in adult female Brown). See also juvenile Blue-footed Booby. Juveniles of Masked and Nazca very similar to one another; distinguishing features still being researched. Young Masked usually show white collar across hindneck; this collar typically lacking in Nazca. Co, E, Br, Ch
BROWN BOOBY Sula leucogaster * 64–74 cm (25–29 in); ws 132–150 cm (52–59 in) Vagrant to Peruvian coastal and offshore waters, known only from sight records (some photographed). Adult recognized by solid brown upperparts and hood that contrast sharply with white belly. Similar to juvenile Masked and Nazca boobies. Juvenile Masked has white collar on hindneck; most Nazca lack the collar, more closely resembling Brown, but also lack the crisp straight-across demarcation between dark breast and white belly of Brown. Adult male has light gray face, and blue-gray bill; head of female all dark, bill yellow. Juvenile is similar in pattern to adult, but white belly is replaced by light brown. Cf. juvenile Red-footed Booby. Co, E, Br, Ch
RED-FOOTED BOOBY Sula sula * 66–77 cm (26–30 in); ws 91–101 cm (36–40 in) Vagrant to Peru; known from a few sight records (some photographed) at sea. Small, slender, and polymorphic. Bright red tarsi of adults diagnostic. White-morph adult similar to Masked and Nazca boobies, but smaller and has white tertials; tail usually white but may be black. Also has black carpal mark on white underwing coverts. Typical dark morph uniformly brown, but intermediate plumages also occur (e.g., body brown with white tail). Dark-morph adult distinguished from juvenile Brown Booby by smaller size and more slender build, lighter brown plumage with no demarcation between breast and belly, darker underwing, pinkish face, and red tarsi. Juvenile similar to larger juvenile Brown, but lacks sharp demarcation between dark breast and paler belly of Brown; also underwing coverts of Red-footed often are darker and belly is paler. Some young Red-footeds are very similar to Brown in plumage pattern, however, and can be difficult to identify when size and shape differences cannot be compared directly. Co, E, Br, Ch
PENGUIN, BOOBIES, GANNET, AND
TROPICBIRDS Penguins are familiar flightless seabirds; they swim well, but on land they stand with a distinctive upright posture and have a peculiar waddling gait. Peruvian and Blue-footed boobies are the most abundant boobies in Peruvian waters; flocks of Peruvian Boobies, in long lines, are a frequent sight along the coast. Cape Gannet is the largest booby reported from Peru, where it is only a vagrant. Tropicbirds are highly pelagic, rare nonbreeding visitors to Peru. Typically seen as single individuals, not in flocks. Fly high over the water with rapid wingbeats; less commonly observed resting on the ocean surface. Capture prey by plunge diving.
HUMBOLDT PENGUIN Spheniscus humboldti 65–70 cm (251⁄2–27⁄2in) Scarce and declining in numbers. Breeds locally on offshore islands; occurs more widely at sea.11Usually seen as single individuals or in very small groups. Swims well, but body rests very low in water, with only head and neck projecting much above surface. Young birds are much paler and less patterned, gradually acquiring darker colors and adult pattern as they age. E, Ch
PERUVIAN BOOBY Sula variegata 71–76 cm (28–30 in); ws 150 cm (59 in) Very common in cold waters. Northernmost breeding site is Isla Lobos de Tierra; some individuals 2 wander north, especially during El Niño events, but in most years is rare to uncommon in northwest. All ages have brown wings with coverts that are narrowly tipped white, producing scaled effect. Cf. Blue-footed Booby, which predominates in northwest but usually is much less common than Peruvian farther south. VOICE Calls at colonies include a coughing chatter and whistles. Co, E, Ch
BLUE-FOOTED BOOBY Sula nebouxii * 76–84 cm (30–33 in); ws 152 cm (60 in) Breeds in large numbers on northern islands (Islas Lobos de Tierra and Lobos de Afuera), and ranges 3 south regularly to central Peru; rare in south, where often associated with El Niño episodes. Adult has diagnostic bright blue feet (rarely visible in flight). Adult also differs from Peruvian by extensive narrow brown streaking on head and neck. In all plumages differs from Peruvian by browner wings (with no white speckling or bars above) and white rump. Browner juvenile is hooded, with white belly and flanks; can be confused with juveniles of Masked and Nazca, but juvenile Blue-footed distinguished by white on rump, base of tail, and nape (note that white nape of Blue-footed is discrete patch, not white collar as in juvenile Masked). Co, E, Ch
CAPE GANNET Morus capensis 85–94 cm (33⁄2–37 in); ws 171–185 cm (67–73 in) Reported from a single sight record (photographed) of an adult off the northern coast. Breeds 1 primarily in southern Africa; not expected to occur again, although breeds in small numbers in Australia and New Zealand and so range may be expanding. Much larger than boobies. Adult also differs from Masked and Nazca boobies by less black on secondaries, by white tertials, and by buffy yellow nape (difficult to see at a distance). Other species of gannets, although equally unexpected, perhaps also could occur in Peru, so note such details as amount and distribution of black on tail and inner wing, and extent of gular patch (if visible). Juvenile is gray-brown, heavily speckled with white. Takes several years to mature; plumage increasingly white as ages.
RED-TAILED TROPICBIRD Phaethon rubricauda * 78 cm (31 in); ws 107 cm (42 in) Very rare vagrant; known only from single sight record from coastal waters of Tacna. Very white adult, with unmistakable long red tail streamers. Subadults have short, often pinkish to whitish tail streamers, but still have extensively white wings of adults. Juvenile more similar to Red-billed Tropicbird but has dusky bill (becoming yellower as bird ages) and little black on outer portion of wing. Ch
RED-BILLED TROPICBIRD Phaethon aethereus * 98 cm (39 in); ws 105 cm (41 in) Highly pelagic; rare nonbreeding visitor to Peruvian waters far from shore. Adult readily recognized 4 by long white tail streamers, red bill, black mask, and barred upperparts. Immature lacks tail streamers, and bill is yellowish; note that black on outer wing includes not only primaries but also primary coverts. Co, E, Br, Ch
End of the services of Amazon Birds - Bird Peru Jungle