Hays Reservoir

Country/territory: Canada

IBA Criteria met: A4i (2008)
For more information about IBA criteria please click here

Area: 1,000 ha

Birds Canada / Nature Canada

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.

Key biodiversity
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.

Recommended citation
BirdLife International (2021) Important Bird Areas factsheet: Hays Reservoir. Downloaded from on 07/12/2021.