Scientific Name: Aechmophorus occidentalis
Taxonomy Group: Birds
Range: British Columbia, Alberta, Saskatchewan, Manitoba
Last COSEWIC Assessment: May 2014
Last COSEWIC Designation: Special Concern
SARA Status: No schedule, No Status
The Western Grebe is a large and conspicuous waterbird. Adapted for an aquatic lifestyle, with lobed feet set well back on a streamlined body, Western Grebes are powerful swimmers but awkward on land. Their white throat, breast and belly contrast with the black and grey plumage of their crown, neck, back and wings. They have bright red eyes and a long, pointed yellowish-green bill. The Western Grebe has been suggested as a bioindicator for wetland ecosystems. (Updated 2017/08/10)
The Western Grebe breeds in British Columbia, Alberta, Saskatchewan, Manitoba, and throughout the western United States. It is a colonial breeder, with an uneven and clustered breeding distribution. It winters mainly in coastal areas from southern Alaska to Mexico, and on inland lakes, particularly in the southern portion of its range. Large numbers formerly occurred in the Salish Sea (Strait of Georgia, Juan de Fuca Strait, and Puget Sound), but in recent years the wintering distribution has apparently shifted southward to California. (Updated 2017/08/10)
Western Grebes nest on marshes and lakes with stands of emergent vegetation, stable water levels, extensive areas of open water, and sufficient populations of prey fish. During migration, they stop mainly on large lakes, but sometimes also use sloughs and river backwaters. On their coastal wintering grounds, they are generally found in sheltered salt or brackish water, in bays, inlets, estuaries, lagoons, and channels. (Updated 2017/08/10)
The Western Grebe is the most gregarious species of North American grebe; wintering flocks of over 10,000 individuals have been observed and nesting colonies can contain thousands of pairs. It engages in complex courtship rituals and is seasonally monogamous. Pairs build a nest together, which they defend aggressively, and they alternate incubation duties. The downy young leave the nest immediately after hatching and are then brooded on their parents’ backs. Western Grebes are mainly piscivorous and both parents feed the young, until they are independent at about 8-10 weeks of age. They usually produce one clutch per year. Typical clutches contain 1-4 eggs and annual productivity ranges from 0.39 to 0.88 young per breeding adult. (Updated 2017/08/10)
On breeding areas, the primary threats to Western Grebes are human disturbance of colonies (e.g., by powerboats and personal watercraft) and habitat degradation (especially destruction of emergent vegetation). Their breeding success and survival can also be negatively impacted by fluctuations in water levels during nesting, disturbance leading to predation on eggs, introduction of non-native fish, recreational and commercial fisheries, declines in prey availability (e.g., due to winterkill of fish), and chemical pollution and contaminants. On coastal wintering areas, oil spills are a major threat. Additional threats in coastal areas include low-volume chronic oil pollution, other chemical pollution and contaminants, harmful algal blooms, bycatch in gillnet fisheries, mortality in derelict fishing gear, changes in prey availability and/or abundance, and possible increases in predation by Bald Eagles. (Updated 2017/08/10)
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
The Western Grebe is a large and conspicuous waterbird. Adapted for an aquatic lifestyle, with lobed feet set well back on a streamlined body, Western Grebes are powerful swimmers but awkward on land. Their white throat, breast and belly contrast with the black and grey plumage of their crown, neck, back and wings. They have bright red eyes and a long, pointed yellowish-green bill. The Western Grebe has been suggested as a bioindicator for wetland ecosystems.
Although population declines have occurred within this waterbird’s Canadian wintering area on the Pacific coast, this could largely be the result of a southern shift in wintering distribution rather than a true loss in population size. Nevertheless, on a continental scale, wintering populations have undergone a 44% decline from 1995 to 2010 based on Christmas Bird Count data. Some of this decline may also be the result of declines on the Canadian breeding grounds. In addition, this species’ propensity to congregate in large groups, both in breeding colonies and on its wintering areas, makes its population susceptible to a variety of threats, including oil spills, water level fluctuations, fisheries bycatch, and declines in prey availability.
The Multi-species Action Plan for Gulf Islands National Park Reserve of Canada applies to lands and waters occurring within the boundaries of Gulf Islands National Park Reserve (GINPR). The plan meets the requirements for action plans set out in the Species at Risk Act (SARA (s.47)) for species requiring an action plan that regularly occur at this site. Measures described in this plan will also provide benefits to other species of conservation concern that regularly occur at GINPR.
His Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, acknowledges receipt, on the making of this Order, of assessments done pursuant to subsection 23(1) of the Species at Risk Act by the Committee on the Status of Endangered Wildlife in Canada with respect to the status of the species set out in the annexed schedule.
Biodiversity is rapidly declining worldwide as species become extinct. Today’s extinction rate is estimated to be between 1 000 and 10 000 times higher than the natural rate. Biodiversity is positively related to ecosystem productivity, health and resiliency (i.e. the ability of an ecosystem to respond to changes or disturbances), and, given the interdependency of species, a loss of biodiversity can lead to decreases in ecosystem function and services (e.g. natural processes such as pest control, pollination, coastal wave attenuation, temperature regulation and carbon fixing). These services are important to the health of Canadians, and also have important ties to Canada’s economy. Small changes within an ecosystem can lead to a loss of individuals and species resulting in adverse, irreversible and broad-ranging effects.
Under Canada’s Species at Risk Act (SARA), the foremost function of COSEWIC is to "assess the status of each wildlife species considered by COSEWIC to be at risk and, as part of the assessment, identify existing and potential threats to the species".
COSEWIC held two Wildlife Species Assessment Meetings in this reporting year (October, 2013 to September, 2014) from November 24 to November 29, 2013 and from April 27 to May 2, 2014. During the current reporting period, COSEWIC assessed the status or reviewed the classification of 56 wildlife species.
The wildlife species assessment results for the 2012-2013 reporting period include the following:
Special Concern: 20
Data Deficient: 0
Not at Risk: 1
Of the 56 wildlife species examined, COSEWIC reviewed the classification of 40 that had been previously assessed. The review of classification for 25 of those wildlife species resulted in a confirmation of the same status as the previous assessment.
The Government of Canada is committed to preventing the disappearance of wildlife species at risk from our lands. As part of its strategy for realizing that commitment, on June 5, 2003, the Government of Canada proclaimed the Species at Risk Act (SARA). Attached to the Act is Schedule 1, the list of the species provided for under SARA, also called the List of Wildlife Species at Risk. Extirpated, Endangered and Threatened species on Schedule 1 benefit from the protection of prohibitions and recovery planning requirements under SARA. Special Concern species benefit from its management planning requirements. Schedule 1 has grown from the original 233 to 521 wildlife species at risk.
Please submit your comments byApril 15, 2015, for terrestrial species undergoing normal consultationsand byOctober 15, 2015, for terrestrial species undergoing extended consultations.For a description of the consultation paths these species will undergo, please see:Species at Risk Public Registry website