Justification This species has an extremely 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). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not 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.

Family/Sub-family Podicipedidae

Species name author (Linnaeus, 1758)

Taxonomic source(s) AERC TAC (2003), AOU checklist (1998 + supplements), Cramp and Simmons (1977-1994), Sibley and Monroe (1990, 1993), Stotz et al. (1996)

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

140,000 - 1,100,000

unset

16,400,000 km²

No

Important Bird Areas Click here to view map showing IBAs where species is recorded and triggers any of the IBA criteria.

Ecology: Behaviour This species is fully migratory¹ and travels over land in stages on a broad front, some populations only moving short distances to the nearest ice-free coast². The species breeds from April to August¹ in solitary isolated pairs^{1, 2}, small loose colonies occasionally forming on lakes with rich extensive feeding areas². During the non-breeding season the species usually remains solitary or forages in pairs or small groups⁵ although flocks of up to c.500 individuals may gather occasionally on the sea during the winter² and flocks of up to 60 individuals may travel together on passage⁵. Habitat Breeding The species breeds on small, shallow fresh¹, brackish or slightly alkaline² waters between 0.5 and 2 m deep and between 1 and 20 ha in area⁵ with rich floating³, submergent and emergent vegetation². Habitats include small pools, marshes with patches of open water and secluded sections of larger lakes and rivers¹. Non-breeding In its wintering range the species frequents coastal inshore waters¹ up to 10-20 m in depth² including sheltered bays¹, lagoons and estuaries⁴. It may also occur on large lake and river systems south of its breeding range^{1, 2}. Diet Its diet consists predominantly of fish and invertebrates such as adult and larval insects (e.g. beetles, dragonflies, mayflies, water bugs, damselflies and caddisflies), crustaceans¹ (e.g. brine shrimp, cladocerans, amphipods, decapods¹, crayfish² and crabs³), molluscs and worms¹. Fish and crustaceans are more important components of the diet during the winter when the species is at sea¹. Breeding site The nest is a platform of aquatic vegetation either floating and anchored to emergent vegetation, built from the lake bottom (where water is shallow) or built on rocks at water level¹. Management information At a breeding lake in Scotland (Loch Ruthven) sedge beds are being extended to provide more nesting habitat for the species⁴.

Threats The main threats to the species are human disturbance, forestry operations around breeding lakes (e.g. afforestation leading to hydrological changes and resulting in reduced numbers of invertebrate prey), fluctuating water levels, and the stocking of lakes with rainbow trout Salmo gairdneri (which competes with the species for aquatic insects)¹. Historical range contractions have also occurred due to acidification and increased humus content of lakes, and the species is vulnerable to hypertrophication². It is commonly caught and accidentally drowning in fishing nets¹ and is particularly vulnerable to oil spills in the marine environment during the winter^{1, 2, 4}.

References 1. del Hoyo et al. (1992). 2. Fjeldsa (2004). 3. Konter (2001). 4. Ogilvie and Rose (2003). 5. Snow and Perrins (1998).

Further web sources of information

Detailed species account from Birds in Europe: population estimates, trends and conservation status (BirdLife International 2004)

Text account compilers Stuart Butchart (BirdLife International), Jonathan Ekstrom (BirdLife International), Lucy Malpas (BirdLife International)

IUCN Red List evaluators Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International)

Recommended citation BirdLife International (2009) Species factsheet: Podiceps auritus. Downloaded from http://www.birdlife.org on 10/2/2010

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

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