The great gray owl is the largest owl in North America. When it spreads its wings the distance from the tip of one wing to the tip of the next is more than 1500 mm, about the height of an average eight year old child. Females are larger than males and can weigh up to 1.8 kg. The great gray owl is a misty gray in colour with many blotches of white and black. It has large round discs of feathers around its eyes. Gray owls have a thick layer of down feathers all over their body to help keep them warm. On top of their heads these feathers can be 100 mm thick.

The great gray owl lives in the pine and spruce forests in the northern parts of North America, Europe and Asia. It stays in Manitoba all year and doesn't migrate south like many of our birds. The gray owl eats small rodents,like mice and voles. In summer it hunts mostly at night, but in winter it hunts at night and during the day. It sits in a tree and uses its sight and its hearing to find small animals, then it swoops down and grabs it with its sharp claws. In winter gray owls can catch mice by pouncing through deep snow with their claws. This owl avoids people and its gray colouring makes it difficult to spot among the trees. The colour and pattern of its feathers make it look like the dead trees it likes to sit in. Owls warn each other about danger. Its alarm call consists of a single loud hoot, followed by several softer notes. The gray owl has few enemies since it is so large. Only other large birds of prey like the great horned owl or red-tailed hawk might attack it.

Great gray owls mate and lay their eggs in March or April. Gray owls don't make their own nests, but use the nests left by other large birds.The female lays 2-5 small white oval eggs. Only the female sits on the nest for the 30 days it takes for the eggs to hatch. The male brings food to her and does most of the hunting for the young when they hatch. The mother will tear up the mice or voles if they are too big for the young to swallow whole, but the young grow fast and soon swallow their food whole. The young owls, called owlets, remain in the nest for three weeks. The young can fly well when they are about 1 month old, but stay with their parents for some time. Both parents hunt and feed the owlets for about 2 months after the young leave the nest, then the female will leave and the only the male remains for a few more weeks. The young owls are on their own by the time they are about 4 months old.