Lava gull  (Larus fuliginosus)

Adult lava gull
Adult lava gull
KingdomAnimalia
PhylumChordata
ClassAves
OrderCharadriiformes
FamilyLaridae
GenusLarus (1)
SizeLength: 51 – 55 cm (2)

Status

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

Description

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).

Range

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

View a distribution map for this species at UNEP World Conservation Monitoring Centre.

Habitat

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).

Biology

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).

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

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.

View information on this species at the UNEP World Conservation Monitoring Centre.

Find out more

For further information on the lava gull see Birdlife International:
http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3247&m=0

For further information on conservation in the Galapágos Islands see the Galapagos Conservation Trust:
http://www.gct.org/

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk

References

  1. IUCN Red List (January, 2007)
    http://www.iucnredlist.org
  2. del Hoyo, J., Elliott, A. and Sargatal, J. (1996) Handbook of the Birds of the World. Vol. 3: Hoatzin to Auks.Lynx Edicions, Barcelona.
  3. Hailman, J.P. (1963) Why is the Galipagos lava gull the color of lava. The Condor, 65: 6 - .
  4. Birdlife International (June, 2007)
    http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3247&m=0
  5. Gottdenker, N.L., Walsh, T., Vargas, H., Merkel, J., Jiménez, G.U., Miller, R.E., Dailey, M. and Parker, P.G. (2005) Assessing the risks of introduced chickens and their pathogens to native birds in the Galápagos Archipelago. Biological Conservation, 126: 429 - 439.
  6. UNEP-WCMC (June, 2007)
    http://www.unep-wcmc.org/sites/wh/pdf/CAPE%20FLORAL%20REGION.pdf
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