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Birds of Zihuatanejo

CLASS AVES

-Animals (Kingdom Animalia)

-Chordates (Phylum Chordata)

-Vertebrates (Subphylum Vertebrata)

-Birds (Class Aves)

-Gannets, Cormorants, and Allies (Order Suliformes)

-Boobies and Gannets (Family Sulidae)

-Typical Boobies (Genus Sula)

-Cocos Booby (Sula brewsteri)


The Brown Booby is a large seabird of the booby family, Sulidae.The average length of the Brown Booby is 65–75 cm with a wingspan of 130–150 cm. Birds weigh from 900–1500 g. At sea, the Brown Booby flies and feeds individually or in flocks The species breeds colonially and roosts communally with other Brown Boobies or other species. Flocks plunge-dive to take small fish, especially when these are driven near the surface by other predators. They only nest on the ground, and roost on solid objects rather than the water surface.

Cocos Booby

Sula brewsteri

Diet

  • Primarily small schooling fish, including sardines, anchovies, flying fish, mackerel, and other pelagic species.

  • Also feeds on squid and other cephalopods.

  • Hunts by soaring over the ocean before making spectacular high-speed plunge-dives, often entering the water from heights of 10–30 m (33–100 ft).

  • Frequently feeds in association with dolphins, tuna, and other seabirds that drive fish to the surface.

Range

  • Endemic to the eastern Pacific Ocean, ranging from the Gulf of California south along the Pacific coast of Mexico through Central America to northern Peru.

  • Common offshore along the Pacific coast of Mexico, including waters off the Zihuatanejo region, particularly around islands, rocky headlands, and productive offshore feeding areas.

  • Breeds on rocky islands and sea cliffs, especially in the Gulf of California, the Islas Marías, and other offshore islands.

Male / Female

  • Male: Brown head, neck, breast, and upperparts with a contrasting white belly and vent; pale bluish-grey bill, yellow eyes, and bluish facial skin. Slightly smaller than the female.

  • Female: Nearly identical in plumage but generally larger and heavier, with a slightly more robust bill.

  • Juveniles: Mostly brown overall, gradually acquiring the adult white underparts over several years.

  • Sexes cannot be reliably distinguished in the field except by size when seen together.

Size

  • Length: 65–75 cm (26–30 in)

  • Wingspan: 132–152 cm (52–60 in)

  • Weight: 900–1,600 g (2.0–3.5 lb)

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