Galapagos Swallow Tailed Gull
Name: Swallow Tailed Gull
Scientific name: Creagrus furcatus
Length: 51 - 58 cm (20 - 22.8 in)
Weight: 610-780 g.
Wingspan: 130 cm (51 in)
Category: Sea Birds
Number of Species: 47
Endemic Species: 13
In total, 47 species of sea birds have been recorded in the Galapagos, 19 of which are resident to the Islands. The sea birds therefore account for nearly one third of all the species ever recorded in the islands and about the same proportion of the resident species.
Seabirds can be conveniently divided into 12 groups, as show in the table below. This shows the number of species recorded in each group and summarizes their status. If also shows the number of endemic species and the number of other species which are represented by endemic subspecies. Species are treated as migrants if they occur annually, vagrants being those recorded less frequently.
Category: Sea Birds
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.
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.
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.
Gives a range of calls which may have a function in echolocation; most frequent alarm call is a rattle interspersed with a piercing "pee".
Feeds mostly nocturnally, usually several miles from land. Flight is buoyant and tern-like.