Thank you Laura for this great Canadian cover with the complete 1986 bird set. It is also used a 1988 stamp showing a Mallard.
Snow or Blue Goose (Chen caerulensces): It breeds in Greenland, Canada and Alaska and it migrates to warmer parts of USA and to Mexico. It feeds on grain and it has two subspecies.
Great Blue Heron (Ardea herodias): It can be found in wetlands and shores of open water in West Indies, Galapagos Islands and North and Central America. It has five subspecies. It feeds on small fish, shrimps, crabs, aquatic insects, small birds, small mammals, reptiles and amphibians.
Spruce Grouse (Falcipennis canadensis): This medium-sized grouse lives in coniferous forests in Alaska and Canada. It feeds on conifer needles, insects, berries and green plants.
Great Horned Owl (Bubo virginianus): It is a large owl native to the Americas. It has about 13 subspecies. It hunts medium-sized mammals and birds and sometimes amphibians, insects, fish, reptiles and crustaceans.

Red-breasted Mergansed (Mergus serrator) is a diving duck. It lives in freshwater rivers and lakes in northern North America, Asia, Europe and Greenland. It is a migratory and game bird. It feeds on small fish, aquatic insects, crustaceans and frogs.

American Black Duck (Anas rubripes) is a dabbling duck. It lives in North America and it is partially migratory. It is also a game bird. It feeds by dabbling in shallow water and grazing on land. It eats plants, aquatic insects and molluscs.

The second prepaid postcard of the set. Mallard (Anas platyrhynchos) is also a migratory and game bird. It lives in temperate and subtropical America, Australia, New Zealand, Europe and Asia in wetlands.

Here is a prepaid postcard from Canada's Duck Decoy's 2006 issue. Barrow's Goldenneye (Bucephala islandica) is a medium-size sea duck. It lives in eastern Canada and Iceland. It is a migratory and game bird. It dives for aquatic insects, crustaceans and pond vegetation. It is named after Sir John Barrow.