Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
Critically Endangered | Endangered | Vulnerable |
---|---|---|
- | - | - |
Year | Category | Criteria |
---|---|---|
2019 | Least Concern | |
2016 | Least Concern | |
2012 | Least Concern | |
2009 | Least Concern | |
2008 | Least Concern | |
2004 | Least Concern | |
2000 | Lower Risk/Least Concern | |
1994 | Lower Risk/Least Concern | |
1988 | Lower Risk/Least Concern |
Migratory status | full migrant | Forest dependency | does not normally occur in forest |
Land-mass type | Average mass | - |
Estimate | Data quality | |
---|---|---|
Extent of Occurrence (breeding/resident) | 8,380,000 km2 | medium |
Extent of Occurrence (non-breeding) | 3,220,000 km2 | medium |
Severely fragmented? | no | - |
Estimate | Data quality | Derivation | Year of estimate | |
---|---|---|---|---|
Population size | 80000-90000 mature individuals | poor | estimated | 2011 |
Population trend | stable | - | inferred | - |
Generation length | 8 years | - | - | - |
Population justification: The population is estimated to number 120,000-130,000 individuals (Wetlands International 2018). This roughly equates to 80,000-90,000 mature individuals.
Trend justification: Data from the North American Breeding Bird Survey, combined for Aechmophorus occidentalis and A. clarkii, implies that the species has undergone a non-significant increase over the past three generations (24 years) (Sauer et al. 2017); whereas in Wetlands International (2018) the population trend is unknown. Given the uncertainty, and the fact that trend data is for these two species combined, the species is tentatively placed here as stable.
Country/Territory | Presence | Origin | Resident | Breeding visitor | Non-breeding visitor | Passage migrant |
---|---|---|---|---|---|---|
Canada | extant | native | yes | yes | ||
Mexico | extant | native | yes | yes | ||
USA | extant | native | yes | yes | yes |
Country/Territory | IBA Name |
---|---|
Canada | Barkley Sound |
Canada | Baynes Sound |
Canada | Boundary Bay - Roberts Bank - Sturgeon Bank (Fraser River Estuary) |
Canada | Delta Marsh |
Canada | Eagle, Namaka and Stobart Lakes |
Canada | English Bay and Burrard Inlet |
Canada | Frank Lake (south) |
Canada | Lesser Slave Lake PP |
Canada | Little Qualicum Estuary to Nanoose Bay |
Mexico | Bahía Todos Santos |
Mexico | Delta del Río Colorado |
USA | Bear River Bay UT02 |
Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
---|---|---|---|
Artificial/Aquatic & Marine | Artificial/Aquatic - Water Storage Areas (over 8ha) | suitable | breeding |
Marine Coastal/Supratidal | Coastal Brackish/Saline Lagoons/Marine Lakes | suitable | breeding |
Marine Neritic | Estuaries | suitable | non-breeding |
Marine Neritic | Pelagic | suitable | non-breeding |
Wetlands (inland) | Bogs, Marshes, Swamps, Fens, Peatlands | suitable | breeding |
Wetlands (inland) | Permanent Freshwater Lakes (over 8ha) | major | breeding |
Wetlands (inland) | Permanent Freshwater Lakes (over 8ha) | major | non-breeding |
Wetlands (inland) | Permanent Saline, Brackish or Alkaline Marshes/Pools | suitable | non-breeding |
Altitude | 0 - 2500 m | Occasional altitudinal limits |
Recommended citation
BirdLife International (2024) Species factsheet: Western Grebe Aechmophorus occidentalis. Downloaded from
https://datazone.birdlife.org/species/factsheet/western-grebe-aechmophorus-occidentalis on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/12/2024.