Horned Grebe Magdalen Islands population
Scientific Name: Podiceps auritus
Taxonomy Group: Birds
Last COSEWIC Assessment: April 2009
Last COSEWIC Designation: Endangered
SARA Status: Schedule 1, Endangered
Image of Horned Grebe
There are two recognized subspecies of the Horned Grebe: the subspecies auritus, which breeds in Eurasia, and the subspecies cornutus, which breeds in North America. Since the species is represented in Canada only by the subspecies cornutus, the name Horned Grebe is used here without specifying the subspecies.
The Horned Grebe is a small duck-like waterbird, 31 to 38 cm long. Its summer breeding plumage includes a distinctive tuft of showy feathers behind the eye, extending back to the nape of the neck and contrasting sharply with its black head. Its foreneck, flanks and upper breast are chestnut-red, while its back is black and its belly white. Its bill is thin and straight, with a pale tip. Males and females are similar in coloration, although the plumage of the male tends to be brighter. Its winter plumage is black and white and characterized by a black crown and white cheeks, which extend almost around the nape. The juvenile plumage is similar to that of adults in winter, but the upper parts are tinged brown. Chicks have dark stripes, which are particularly visible on the head and neck.
Distribution and Population
The Horned Grebe is found across Eurasia and in northwestern North America, primarily in Canada. In the United States, it breeds in central and southern Alaska as well as locally in some northwestern states. In Canada, it breeds mainly in all of the Prairies, but also in British Columbia, Yukon, the Mackenzie River Valley in the Northwest Territories, extreme southern Nunavut, northwestern Ontario and the Magdalen Islands, where a small isolated breeding population has persisted for at least a century. In Canada, the various colonies are grouped into two populations separated by 2000 km: the Western population, which includes birds breeding from British Columbia to the extreme northwestern part of Ontario; and the Magdalen Islands population, which includes birds breeding in this archipelago and other sporadic breeders that occur in Quebec. The wintering grounds of the Magdalen Islands population are unknown, but it is presumed that the birds winter along the Atlantic coast of North America. It is possible that the Magdalen Islands population and the Western population overlap on the wintering range. According to surveys carried out between 1993 and 2006, the Magdalen Islands population is estimated at an average of 15 adults. Since 1993, no more than 25 adults have been seen during the same breeding season, and only 5 adults were observed in 2005. The population on the Magdalen Islands declined by 2% per year between 1993 and 2007. The analysis of annual surveys suggests that the population has declined by 22% over the last three generations. Moreover, most of the birds and nests found recently, from 2000 to 2007, during the breeding season were concentrated on East Pond and on Brion Island. Other nesting areas of the archipelago seem to be deserted.
The Horned Grebe breeds primarily in temperate zones such as the Canadian Prairies, but can also be found in more boreal and subarctic zones. It generally nests in freshwater and occasionally in brackish water on small permanent or semi-permanent ponds which last until autumn, but it also uses marshes and shallow bays on lake borders. These water bodies are found in both open and forested areas. Breeding ponds must contain areas of open water and beds of emergent vegetation that provide nest material, concealment and anchorage, and protection for the young. Little information is available on the particular requirements of the Horned Grebe during migration, but birds have been observed on lakes, rivers and marshes. Some birds follow coastlines for part of their migration. Horned Grebes generally winter in marine habitats, mainly estuaries and bays. Birds are found in greatest numbers in coastal habitats, particularly in areas that provide some degree of protection. On the Magdalen Islands, the number of ponds identified as suitable for Horned Grebe breeding seems to be stable. Nevertheless, other factors, such as the presence of the Pied-billed Grebe, eutrophication or the drying of certain ponds, have reduced the availability of preferred habitat.
The Horned Grebe is generally a solitary nester, but up to 20 pairs may nest in the same pond if it is sufficiently large and there are abundant food resources. This bird generally breeds around one year of age. Site and mate fidelity have been observed in this species. The Horned Grebe is aggressive when defending its territory, rarely leaving its nest unguarded. The nest is composed of plant matter and is affixed to emergent vegetation, in shallow water. This grebe occasionally builds its nest in areas devoid of vegetation, establishing it on masses of floating algae, shallowly submerged logs, floating branches or platforms of human origin. On the Magdalen Islands, the Horned Grebe uses primarily bulrushes for nest construction. Females in the Western population lay on average 5.3 to 5.9 eggs per clutch, whereas in the Magdalen Islands population, the average clutch size is 4.4 and ranges from 3 to 6 eggs. Egg laying stretches over several days, with the eggs laid at one- to two-day intervals. Both parents share incubation of the eggs. The pair can also rebuild its nest and can lay up to four replacement clutches if previous clutches are destroyed. On the Magdalen Islands, potential predators of the Horned Grebe are Red Fox, Great Blue Heron, American Crow and Common Raven. Minks recently escaped from mink-rearing farms are also potential predators. The Horned Grebe is a diver that catches and eats most of its prey underwater. Its diet consists primarily of aquatic insects and fish in the summer, and fish, crustaceans and polychaetes (marine worms) in the winter. On the Magdalen Islands, adults gather on East Pond before migrating to the wintering areas in late September or early October. The Horned Grebe is vulnerable to changes in water quality near its breeding sites.
The factors limiting Horned Grebe populations in Canada are not known, but several possible causes for the decline have been identified, including oil spills on their wintering grounds. At sea, these birds are particularly vulnerable, since they spend most of their time on the water. Competition with Pied-billed Grebes for breeding habitat could be a limiting factor for all Horned Grebe populations. The Pied-billed Grebe was first recorded on the Magdalen Islands in 1954 and has since grown to 25 breeding pairs. This species may prevent Horned Grebes from nesting on some ponds in the archipelago. Disturbance from human visitors also threatens breeding birds. Squatter camps close to breeding ponds are a source of disturbance. Finally, birds are killed annually in fishing nets during both spring and fall migrations. The small size of the Magdalen Islands population makes it particularly vulnerable to the above-mentioned threats. In particular, any predation of adults, chicks or nests can affect the persistence of this small population.
Federal ProtectionThe Horned Grebe, Magdalen Islands population, is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.
In Quebec, the Horned Grebe is protected under the Quebec Act Respecting Threatened or Vulnerable Species. However, this designation does not offer any protection to the species’ breeding habitat. The species is also protected under the Migratory Birds Convention Act, 1994, which prohibits harming migratory birds, their nests or their eggs. On the Magdalen Islands, almost half of the ponds preferred by the Horned Grebe are located in the Pointe de l’Est National Wildlife Area, which is federal land protected under the Species at Risk Act. Furthermore, at Brion Island, all the ponds are located within the limits of the Brion Island Ecological Reserve, under the jurisdiction of the Quebec government.
Provincial and Territorial Protection
Status of Recovery Planning
Recovery Strategies :
Name Recovery Strategy for the Horned Grebe (Podiceps auritus), Magdalen Islands Population, in Canada
Status Final posting on SAR registry
CWS-Quebec Species at Risk Recovery Unit
Unité du rétablissement des espèces en péril du SCF-QC - Chair/Contact -
Phone: 1-855-253-6708 Send Email
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.
11 record(s) found.
- COSEWIC Status Reports (1 record(s) found.)
- COSEWIC Assessments (1 record(s) found.)
- Response Statements (1 record(s) found.)
- Recovery Strategies (1 record(s) found.)
- Action Plans (2 record(s) found.)
- Orders (2 record(s) found.)
- COSEWIC Annual Reports (1 record(s) found.)
- Consultation Documents (1 record(s) found.)
- Critical Habitat Descriptions in the Canada Gazette (1 record(s) found.)
COSEWIC Status Reports
COSEWIC Annual Reports
COSEWIC Annual Report - 2009 (2009)2009 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.
Critical Habitat Descriptions in the Canada Gazette
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