Alonsa, Manitoba
Duck Island is located in the northeastern corner of the southern basin of Lake Manitoba. This Important Bird Area includes Duck Island (also known as Big Birch Island) and several smaller unnamed neighbouring islands. The habitats of these islands are unrecorded, but are assumed to be as noted here.
Large numbers of American White Pelicans breed on Duck Island and its associated islands. In 1986, there were 540 nests on the Duck Islands. In addition, the second island south west of Duck Island had 278 pelican nests in 1991.
Three other colonial waterbird species also nest on these islands. In 1986, there were 400 Common Tern nests on the fourth island west of Duck Island, and Double-crested Cormorants and Ring-billed Gulls nesting on the second island southwest of Duck Island. In 1986, there were 650 pairs of cormorants and 2,000 pairs of Ring-billed Gulls, while in 1991 there were 1,885 cormorant pairs and 5,000 adult Ring-billed Gulls on this island.
Colonial waterbirds nesting in Lake Manitoba face several problems. Some residents whose livelihood depends on fishing feel that the birds are eating too many fish. As a result, birds are sometimes shot, or nests are destroyed.
Lake Manitoba is affected by high water levels in some years, in part due to increased capacity on the lake from the Portage Diversion and the Assiniboine River. This may lead to flooding of some low-lying islands and temporary loss of habitat in the IBA.
IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status