IBA Hays Reservoir
Hays, Alberta
Site Summary
AB075 Latitude
50.062° N
111.832° W
785 m
8.99 km²
freshwater lake
Land Use:
Water management
Potential or ongoing Threats:
Disturbance, Other decline in habitat quality, Recreation/tourism
IBA Criteria: Globally Significant: Congregatory Species
Conservation status:
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Site Description
Hays Reservoir is located about halfway between Medicine Hat and Lethbridge in southern Alberta. It is an artificial reservoir with five small islands that are used by colonial nesting birds. The reservoir contains little marsh development, but it is surrounded by native mixed grassland habitat. An irrigation canal feeds the reservoir. The nationally vulnerable Great Plains Toad was reported breeding at this site in 1982.
Hays Reservoir supports a globally significant breeding population of American White Pelicans. In 1998, 3,850 nests were recorded at the reservoir. This number is over 4% of this species global population and the colony is the largest in Alberta.

Several other colonial waterbird species also nest in the reservoir. It supports one of the largest Ring-billed Gull colonies in Alberta (5758 nests in 1998). In 1998, 328 Double-crested Cormorant and 228 California Gull nests were counted. Black-crowned Night-Herons and Common Terns nest here, as do Caspian Terns on rare occasions - in 1998, one nest was found.

In addition to colonial waterbirds, this site is an important staging, moulting and production area for waterfowl, such as dabbling ducks, diving ducks and geese. The reservoir also provides habitat for migrating shorebirds.

IBA Criteria
SpeciesT | A | I Links Date Season Number G C N
American White Pelican 1998 SU 1,804 - 7,700
Note: species shown in bold indicate that the maximum number exceeds at least one of the IBA thresholds (sub-regional, regional or global). The site may still not qualify for that level of IBA if the maximum number reflects an exceptional or historical occurrence.
Conservation Issues
Colonial nesting pelicans and cormorants are sensitive to human intrusion on and around nesting islands. Excessive disturbance of birds could result in exposure of eggs and young and consequently increased susceptibility to gull predation. This site has been recognized provincially as an environmentally significant area.

The IBA Program is an international conservation initiative coordinated by BirdLife International. The Canadian co-partners for the IBA Program are Birds Canada and Nature Canada.
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