LC
Western Grebe Aechmophorus occidentalis



Taxonomy

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.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
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
Species attributes

Migratory status full migrant Forest dependency does not normally occur in forest
Land-mass type Average mass -
Range

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 -
Population
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 distribution
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

Important Bird and Biodiversity Areas (IBA)
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

Habitats & altitude
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.