The lava gull feeds on a wide variety of animals; crustaceans, baby marine iguanas, small fish and seabird eggs, and will also scavenge around fishing boats and at human settlements for offal and scraps. It is also known to feed on the placentas of sea lions. Feeding occurs along the shore, which it flies along at three to five meters while scanning for food, or whilst hovering over the water's surface, waiting to snatch any floating offal (2). The lava gull is a solitary nester that breeds throughout the year, with a peak between May and October. Within a large territory, two eggs are laid in a simple scrape nest (2).

There are less than 800 lava gulls alive, making this the rarest gull in the world (2). The name comes from its dark sooty-grey plumage, which is darkest on the wings and paler on the belly, and also because it spends much of its time on the lava rocks strewn on the shores of the Galapágos Islands (3). The bill and feet are black, and the head is almost black, with conspicuous white eyelids (4).

Galapagos Islands.

Eastern South Pacific, Galapagos Islands

Larus fuliginosus breeds only in the Galápagos Islands, Ecuador. It is widespread throughout the archipelago, with possibly the most dense populations found at Puerto Ayora (Santa Cruz)^3,5, Puerto Baquerizo Moreno (San Cristóbal) and Puerto Villamil (Isabela)⁵. In 1963, a survey of 56 km of coastline on the south and east of Santa Cruz found eight territories, which was extrapolated over the remaining coastline in the archipelago to give an estimate of 300-400 pairs. This was considered an overestimate. It has been suggested that the tiny population is probably a consequence of its confinement to linear feeding grounds of restricted range, which provide a limited food supply for much of the year⁴.

The lava gull breeds only on the Galapágos Islands, where it is widespread (4).

Habitat and Ecology

Systems

• Terrestrial
• Marine

Occurs on sandy and gravely beaches, and nests in sheltered places near calm water, such as lagoons and pools, usually close to the sea. It can be found in areas of high food availability, such as harbours, when foraging (2) (4).

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 2008
  Vulnerable
• 2006
  Vulnerable
• 2004
  Vulnerable
• 2000
  Vulnerable
• 1996
  Vulnerable
• 1994
  Vulnerable
• 1988
  Near Threatened

Classified as Vulnerable (VU) on the IUCN Red List 2006 (1).

Population

Population Trend

Major Threats

Although the number of lava gulls is assumed to be stable, there are several potential threats which could have a significant impact on such a small population. Newcastle disease has been identified in domestic chickens on the Galapágos Islands, and poses an imminent threat to lava gulls. With an increase in poultry production, concern has been expressed that there is an increased risk of disease transfer from chickens to native Galapágos bird species which have little resistance to introduced pathogens (5). Other potential threats include an increase in human populations with the associated development, predation and disturbance by introduced species, and an increase in tourists acting as potential vectors for further alien species (4) (6)

Conservation Actions

The majority of the Galapágos archipelago is designated a National Park and World Heritage Site (6), but still remains vulnerable to those threats mentioned above. Population surveys and long-term monitoring would be beneficial in assessing the status of this poorly known species (4), and enabling appropriate conservation measures to be implemented if required.