Animalia > Chordata > Aves > Charadriiformes > Laridae > Larus > Larus atlanticus

Larus atlanticus (Olrog's Gull)

Wikipedia Abstract

Olrog's gull (Larus atlanticus) is a species of gull found along the Atlantic coast of southern Brazil, Uruguay and northern Argentina. It was formerly considered a subspecies of the very similar L. belcheri. It is a large gull with a black back and wings, white head and underparts, a black band in the otherwise white tail, and a yellow bill with a red and black tip. Non-breeding adults have a blackish head and a white eye-ring. The species is named after Swedish-Argentine biologist Claes C. Olrog.It has a rather restricted breeding range and is threatened by habitat loss, and the IUCN rate it as being "Near Threatened".
View Wikipedia Record: Larus atlanticus

EDGE Analysis

Uniqueness Scale: Similiar (0) 
 Unique (100)
Uniqueness & Vulnerability Scale: Similiar & Secure (0) 
 Unique & Vulnerable (100)
ED Score: 1.95882
EDGE Score: 2.47108


Adult Weight [1]  2.05 lbs (930 g)
Diet [2]  Carnivore (Invertebrates), Carnivore (Vertebrates), Piscivore
Diet - Fish [2]  10 %
Diet - Invertibrates [2]  80 %
Diet - Scavenger [2]  10 %
Forages - Water Surface [2]  100 %
Clutch Size [1]  2
Incubation [1]  26 days
Wing Span [1]  4.4 feet (1.35 m)


Name Countries Ecozone Biome Species Report Climate Land
Espinal Argentina Neotropic Temperate Grasslands, Savannas, and Shrublands
Humid Pampas Argentina Neotropic Temperate Grasslands, Savannas, and Shrublands
Patagonian steppe Chile, Argentina Neotropic Temperate Grasslands, Savannas, and Shrublands
Uruguayan savanna Uruguay, Brazil, Argentina Neotropic Tropical and Subtropical Grasslands, Savannas, and Shrublands

Protected Areas

Name IUCN Category Area acres Location Species Website Climate Land Use
Parque Atlantico Mar Chiquita Nature Reserve VI 706059 Cordoba, Argentina  

Important Bird Areas

BirdLife Species Factsheet: View Factsheet
Name Location  IBA Criteria   Website   Climate   Land Use 
Arroyo Maldonado wetlands Uruguay A1
Bahía de Samborombón y Punta Rasa Argentina A1, A4i, A4iii
Cuenca del Río Salado Argentina A1
Estuario del Río Gallegos Argentina A1, A2, A3, A4i
Estuário da Laguna dos Patos Brazil A1, A3, A4i
José Ignacio Lagoon Uruguay A1, A4i
Laguna Melincué Argentina A1, A4i
Norte del Golfo San Jorge Argentina A1, A4i, A4ii, A4iii
Parque Costero del Sur Argentina A1, A3
Parque Nacional da Lagoa do Peixe Brazil A1, A4i, A4iii
Península y Bahía de San Julián Argentina A1, A3, A4ii, A4iii  
Penino Beach and Santa Lucía Wetlands Uruguay A1, A2
Playa Punta Mogotes y Puerto de Mar del Plata Argentina A1, A4i
Reserva Campos del Tuyú, Estancia El Palenque y Los Ingleses Argentina A1  
Reserva de Biosfera Albufera de Mar Chiquita Argentina A1, A4i, A4iii
Reserva de Uso Múltiple Bañados del Río Dulce y Laguna Mar Chiquita Argentina A1, A2, A4i, A4iii
Reserva de Uso Múltiple de Bahía Blanca, Bahía Falsa y Bahía Verde Argentina A1, A4i
Reserva de Uso Múltiple San Blas y Refugio de Vida silvestre Complementario Argentina A1
Reserva Natural de Uso Múltiple Isla Martín García Argentina A1
Reserva Natural Punta Lara Argentina A1
San Antonio Oeste Argentina A1, A4i, A4iii
Villa marítima El Cóndor Argentina A1

Prey / Diet

Balanus glandula (Acorn barnacle)[3]
Cyrtograpsus altimanus[4]
Cyrtograpsus angulatus[5]
Neohelice granulata[3]

Prey / Diet Overlap

Competing SpeciesCommon Prey Count
Haematopus palliatus (American Oystercatcher)1
Podiceps major major (Great Grebe)1


Parasitized by 
Maritrema bonaerensis <Unverified Name>[6]
Microphallus szidati[6]

Range Map



Attributes / relations provided by
1del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
2Hamish Wilman, Jonathan Belmaker, Jennifer Simpson, Carolina de la Rosa, Marcelo M. Rivadeneira, and Walter Jetz. 2014. EltonTraits 1.0: Species-level foraging attributes of the world's birds and mammals. Ecology 95:2027
4Effect of Feeding Technique and Prey Characteristics on the Feeding Rate of Olrog's Gulls (Larus atlanticus), Nicolás Suárez, María Valeria Retana and Pablo Yorio, Waterbirds 37(1):79-87. 2014
5Jorrit H. Poelen, James D. Simons and Chris J. Mungall. (2014). Global Biotic Interactions: An open infrastructure to share and analyze species-interaction datasets. Ecological Informatics.
6Gibson, D. I., Bray, R. A., & Harris, E. A. (Compilers) (2005). Host-Parasite Database of the Natural History Museum, London
Ecoregions provided by World Wide Fund For Nature (WWF). WildFinder: Online database of species distributions, ver. 01.06 WWF WildFINDER
Images provided by Google Image Search
Abstract provided by DBpedia licensed under a Creative Commons License
Weather provided by NOAA METAR Data Access