Galapagos Gulls

Category: Sea Birds
Family: Laridae
Endemic Subspecies: Swallow-tailed Gull; Lava Gull

Five species of Gulls have been recorded in Galapagos, which include 2 residents, 2 migrants and 1 vagrant. Gulls are medium-sized to largish seabirds with long, pointed wings and longish, rather stout, hook-tipped bills, usually with a marked gonydeal angle. Their legs are longish and their feet webbed. The gulls recorded in Galápagos are predominantly grey and white in adult plumage, although the Lava Gull is wholly grey. The sexes are alike. Birds take a number of years to attain adult plumage and immature plumages are variable, often making identification difficult. Gulls feed by picking food from the surface of the water or by scavenging, often along the shoreline.

Scientific Name: Creagrus furcatus
Family: Laridae
Length: 51 - 58 cm (20 - 22.8 in)
Wingspan: 130 cm (51 in)

Common resident, especially in the eastern most islands. Population Estimated at. 10,000-15,000 pairs in over 50 colonies. Endemic, except for a small colony on Malpelo Island off the west coast of Colombia. Breeds throughout the year, nesting in the shore zone.

Identification: Unmistakable; the only common whitish gull with a distinctive forked tail. ADULT: Upper parts and neck grey; under parts white. In breeding plumage has dark grey head, large eye with red eye-ring, and black bill with pale base and tip. Non-breeding adults have white head with dark eye-patch. In flight shows distinctive 'triangular' pattern of grey back and wing-coverts, white secondaries and black primaries. JUVENILE: Head and under parts white, with black eye-patch and ear-spot; upper parts scaly brown and white.

Voice: Gives a range of calls which may have a function in echolocation; most frequent alarm call is a rattle interspersed with a piercing "pee".

Behavior: Feeds mostly nocturnally, usually several miles from land. Flight is bouyant and tern-like.

LAVA GULL

Scientific Name: Larus fuliginosus
Family: Laridae
Length: 51 - 55 cm (20 - 21.8 in)
Wingspan: 130 cm (51 in)

Conservation Status: Vulnerable

Widely distributed resident of Galapagos. The total world population occurs on the Galapagos Islands only and is fewer than 400 pairs. Breeds throughout the year, but mainly from May to October, nesting singly in the shore zone.

Identification: Unmistakable; the only all-dark gull, with heavy bill. ADULT: Blackish head with white eyelids, sooty-grey upper parts and breast, paler on belly. In flight, darker primaries contrast with rest of wing; rump and outer rail feathers whitish. JUVENILE: Dark chocolate-brown overall, except for pale rump. FIRST-WINTER / FlRST-SUMMER: Similar to juvenile, but has greyer tints to head and upperparts.

Behavior: A tideline scavenger, rarely alighting on the sea.

Scientific Name: Larus pipixcan
Family: Laridae
Length: 32 - 38 cm (12.6 - 14.9 in)
Wingspan: 87 - 91 cm (34 - 35.8 in)

Regular migrant, mostly from October to May. Breeds in North America, spending the northern winter on the west coast of South America.

Identification: A smallish gull. ADULT BREEDING: White under parts and tail with medium-gray mantle and upper wings. Black hood with bold white crescents above and below eye. Bill dark red. In flight shows equal amount of black and white at wing-tip. ADULT NON-BREEDlNG: Differs from breeding adult in much reduced hood, with black only around and behind the eye. FIRST-WINTER: Saddle dark grey; rest of upper parts and upper wings gray-brown; partial hood as in non-breeding adult. In flight, white tail has black sub terminal band which does not extend to the edge of the rail as the outermost tail feathers are white.