Although there are several species of geese in North America, it is the Canada goose (Branta canadensis) that is the most recognizable. The large size, black head and neck, and prominent white cheek patch of this bird makes identification easy, along with their distinctive "V" shaped flying pattern and honking calls.

At least ten subspecies or races of Canada geese have been identified, with differences primarily noted in size, voice, and plumage. The "giant" form (Branta canadensis maxima) however, is the one that has settled most comfortably on a year-round basis among people. Considering this bird's historical brush with extinction, their commonplace presence on the suburban landscape today is truly remarkable.

By the end of the 19th century, over-hunting of Canada geese for their meat and feathers had reduced their populations to near extinction. The enactment of the landmark Migratory Bird Treaty Act (MBTA) in 1916 served to broadly protect migratory birds and helped preserve the dwindling numbers of Canada geese, but scientists still believed that the "giant" Canada goose had vanished forever.

In the early 1960s, however, small groups of this subspecies were rediscovered and federal and state wildlife agencies began a concerted effort to rebuild their populations. The geese raised in captivity and moved about by wildlife agencies were probably never strong migrants, and any tendency they may have had to migrate was affected by their captive propagation. Such birds have come to be known as "resident" Canada geese: those who tend to stay year-round in the rich and provident urban and suburban landscapes.

Like all waterfowl, Canada geese are traditionally associated with lakes and ponds, but they also spend time on land and will nest some distance from water if the site seems safe. Artificial ponds and lakes, storm water impoundments, and vast expanses of good grazing surfaces typical of municipal parks, corporate and school campuses, golf courses, and other human-built environments are ideal habitat for geese. This is the main reason they have settled in to year-round residency and have grown in numbers in suburban and urban areas.

Canada geese are attracted to short grasslands, which explains their affinity for the vast, feverishly tended lawns of suburbia. Grass has become the major and preferred source of food for geese throughout the spring and summer. They tend to eat and loaf in grassy areas with open sight lines and access to a body of water, so that they may easily see and escape from predators. Corn and other agricultural crops are especially important to migrating flocks of Canada geese, who can be found foraging in fields as migration progresses.

Canada geese are strongly monogamous and do not usually pair until a rather advanced age—for birds—of about three years. But geese also live comparably long lives, as long as 20 years. Because of their strong family attachments and pair-bonding between adults, geese will vigorously defend both nests and chicks—a species characteristic that often leads to conflicts with people. Their preferred nesting sites are usually near water with a good view of the surrounding area; they show a great preference for islands as well as peninsulas when choosing nest sites. However, geese will also nest in less than ideal places, including some that seem very inappropriate to people, such as landscaped areas in parking lots, planters next to busy building entrances, or flat roofs.

Eggs are laid during March and April. Geese tend to use the same nest site year after year, usually laying five or six eggs and incubating them for 28 days. Both parents protect and defend the nest and goslings until they are approximately ten weeks old and are able to fly. Within a day or two of hatching, parents may lead their precocious offspring as far as two miles away to grass and water if their original nest site did not offer these amenities.

Adult Canada geese molt (completely shed and replace their flight feathers) each summer and cannot fly during this month-long period. After adults have molted completely and young geese have grown their first flight feathers, they begin to travel in groups or flocks. "Resident" Canada geese usually move only short distances for the winter, but bad weather can find them moving hundreds of miles in search of open water and forage.