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LC
Hartlaub's Gull Larus hartlaubii

Justification
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Taxonomic source(s)
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

Distribution and population
The King Gull is a non-migratory breeding resident endemic to the Atlantic Ocean coastline of South Africa and Namibia (del Hoyo et al. 1996).

Trend justification
The overall population trend is increasing, although some populations have unknown trends (Wetlands International 2006).

Ecology
Behaviour This species is predominantly sedentary (Urban et al. 1986, del Hoyo et al. 1996, Hockey et al. 2005) although it may disperse short distances along the coast outside of the breeding season (del Hoyo et al. 1996, Hockey et al. 2005). Information about the timing of breeding is conflicting, although it appears to vary geographically, with the species breeding in any month of the year in some areas (del Hoyo et al. 1996). The species breeds in colonies of 10-1,000 pairs (Urban et al. 1986, del Hoyo et al. 1996), frequently with Greater Crested Terns Sterna bergii and other colonial species (Urban et al. 1986, Williams et al. 1990, del Hoyo et al. 1996). It remains gregarious outside of the breeding season, occurring in large groups (e.g. of 60 [Hockey et al. 2005] to several hundred [Urban et al. 1986] individuals) that forage and roost together (Urban et al. 1986, Hockey et al. 2005). Habitat The species inhabits coastal areas (del Hoyo et al. 1996), and is rarely seen further than 20 km from land (Williams et al. 1990) (usually observed within 3 km [Urban et al. 1986]). Suitable habitats include shallow inshore waters (Urban et al. 1986), where water is less than 50 m deep, estuaries, lagoons (Hockey et al. 2005), intertidal zones, beaches (Urban et al. 1986) and harbours (Urban et al. 1986, del Hoyo et al. 1996), also occurring on land at refuse dumps (del Hoyo et al. 1996), abattoirs (Urban et al. 1986, del Hoyo et al. 1996) and sewage and salt works (Urban et al. 1986, del Hoyo et al. 1996). It breeds on low, flat, rocky offshore islands (del Hoyo et al. 1996, Hockey et al. 2005), and is strongly associated with kelp beds (a large part of its diet consists of invertebrates associated with stranded kelp [Williams et al. 1990]). Diet Its diet consists predominantly of marine invertebrates (del Hoyo et al. 1996) (e.g. kelp fly larvae, amphipods [Urban et al. 1986], molluscs and crustaceans [Hockey et al. 2005]), especially those associated with stranded kelp (Williams et al. 1990), as well as terrestrial insects (del Hoyo et al. 1996) (e.g. crickets, grasshoppers, beetles, moths and ants [Hockey et al. 2005]), small fish (del Hoyo et al. 1996), earthworms (Urban et al. 1986, del Hoyo et al. 1996), the fruits of low-growing shrubs (Hockey et al. 2005), offal and refuse (Urban et al. 1986, del Hoyo et al. 1996, Hockey et al. 2005). Breeding site The species breeds colonially, with nests spaced 1-2 m (Urban et al. 1986, del Hoyo et al. 1996). Suitable sites include low, flat, rocky offshore islands (del Hoyo et al. 1996, Hockey et al. 2005) and artificial structures (Hockey et al. 2005) such as dykes in sewage lagoons and saltpans (Urban et al. 1986, del Hoyo et al. 1996) and the roofs of buildings (Urban et al. 1986, del Hoyo et al. 1996), although it does show a preference for bare or slightly vegetated ground (Urban et al. 1986, del Hoyo et al. 1996) (e.g. with beach halophytes [Urban et al. 1986]), that are associated with sites of more substantial vegetation (Urban et al. 1986). The nest is a slight hollow (Urban et al. 1986, del Hoyo et al. 1996) or a woven structure of plant stems (Hockey et al. 2005) that is typically placed on rocky surfaces (Urban et al. 1986, Hockey et al. 2005) or occasionally in reedbeds (Hockey et al. 2005), or up to 20-50 cm high in densely-matted sclerophyllous shrubs (Urban et al. 1986, del Hoyo et al. 1996).

Threats
The species is threatened by a high rate of breeding failure brought about by a number of man-made and natural causes (del Hoyo et al. 1996). For example storms (Williams et al. 1990) and changing water levels in artificial breeding sites (Blaker 1967) may flood colonies, and abnormally high sea-surface temperatures may reduce food availability and lower reproductive succes (Williams et al. 1990). Natural predators such as Kelp Gulls Larus dominicanus, African Sacred Ibises Threskiornis aethiopicus and Cattle Egrets Bubulcus ibis eat eggs, chicks and occasionally adults, and Greater Crested Terns Sterna bergii frequently displace incubating pairs, resulting in egg mortality (Williams et al. 1990, del Hoyo et al. 1996). Introduced predators on offshore islands such as mongooses (del Hoyo et al. 1996) (e.g. Galerella pulverulentus and yellow mongoose Cynictis penicillata [Williams et al. 1990]), domestic cat Felis catus (Williams et al. 1990, Hockey et al. 2005) and cape fox Vulpes chama (Williams et al. 1990) threaten breeding colonies (Williams et al. 1990, Hockey et al. 2005), and colonies near airports are often deliberately disturbed (by breaking eggs, collecting chicks and shooting adults) to reduce the threat of air strikes (Hockey et al. 2005). The species is also susceptible to avian botulism, so may be threatened by future outbreaks of the disease (Blaker 1967, Williams et al. 1990).

References
Blaker, D. 1967. An outbreak of Botulinus poisoning among waterbirds. Ostrich 38(2): 144-147.

del Hoyo, J.; Elliott, A.; Sargatal, J. 1996. Handbook of the Birds of the World, vol. 3: Hoatzin to Auks. Lynx Edicions, Barcelona, Spain.

Delany, S.; Scott, D. 2006. Waterbird population estimates. Wetlands International, Wageningen, The Netherlands.

Hockey, P. A. R.; Dean, W. R. J.; Ryan, P. G. 2005. Roberts birds of southern Africa. Trustees of the John Voelcker Bird Book Fund, Cape Town, South Africa.

Urban, E. K.; Fry, C. H.; Keith, S. 1986. The birds of Africa vol. II. Academic Press, London.

Williams, A. J.; Steele, W. K.; Cooper, J.; Crawford, R. J. M. 1990. Distribution, population size and conservation of Hartlaub's Gull Larus hartlaubii. Ostrich 61(1-2): 66-76.

Further web sources of information
Explore HBW Alive for further information on this species

Search for photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Ekstrom, J., Butchart, S., Malpas, L., Calvert, R.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2014) Species factsheet: Larus hartlaubii. Downloaded from http://www.birdlife.org on 28/12/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/12/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Key facts
Current IUCN Red List category Least Concern
Family Laridae (Gulls, Terns, Skimmers)
Species name author Bruch, 1853
Population size mature individuals
Population trend Increasing
Distribution size (breeding/resident) 70,000 km2
Country endemic? No
Links to further information
- Additional Information on this species
- Projected distributions under climate change