Goose banding helps make better management decisions
Wildlife biologists, technicians, and volunteers throughout Minnesota have recently been busy once again in what can be truthfully called bona fide "wild goose chases." The annual activity of capturing and banding Canada geese, which commences late June to mid-July when adults are molting and their goslings cannot fly, assist wildlife research biologists better understand goose population dynamics, which, in turn, provides important data for applying harvest management by wildlife managers.
Each goose that is captured is then banded with a unique, numbered metal leg band. Additional information that is collected includes determining each goose's sex and their relative age (adult or juvenile). All of this information, including the band numbers, are recorded and entered into a database for each of the respective banded geese. Sometimes a captured goose is discovered to already be wearing a leg band. In such cases, the leg bands of the recaptured goose are recorded as well.
You would think that capturing flightless geese would be easy, but in actuality the activity is not as simple as it sounds. While the geese are indeed unable to fly during this short period in late June to much of July, the birds are far from immobile or helpless. Despite their inability to fly, they can still run, they can still hide, they can still swim, and they can see and hear extremely well. Believe me, Canada geese are well equipped to outsmart any pursuing biologist.
A goose roundup usually involves a dozen or more people and sometimes as many as a hundred or more geese at any one time. The roundups typically begin in the water where teams of people operating boats and paddling canoes search for groups of geese. Once found, the geese are gradually "herded" to land where people (trappers) are waiting to capture them.
After the geese have walked onto dry land and have reached far enough inland, the trappers stand and surround the confused geese. Each of the trappers -- some carrying large panels that serve as sections for a four-sided temporary pen -- walk slowly toward the geese and eventually close-in until the birds find themselves completely trapped inside the makeshift pen.
With someone inside the pen among the trapped geese, one goose at a time is carefully captured and given to those people waiting outside the pen. Each goose is quickly carried to any number of awaiting "banders" (people banding geese) while other people work to distribute leg bands, record data, and sometimes to assist releasing the geese back into the wild. Everything is completed swiftly in order to reduce handling time, thus reducing stress the birds might experience from the ordeal.
It is, without a doubt, interesting to handle and observe this exceptional bird up close. And naturally, its natural history is fascinating too. Often incorrectly called the Canadian goose, the Canada goose is the most wide-spread and recognizable North American goose. Their most recognizable traits are the black head and neck with the distinctive white cheek patches on both sides of the head. Bodies are colored gray-brown and their breasts are a light gray. Both sexes look identical.
Despite the ease in identifying this species of goose, Canada geese are actually a confusing lot. Taxonomists recognize at least eleven or twelve races -- maybe more -- of the species. All are similar looking, but each varies in size and distribution. Variation in plumage coloration and markings also occurs amongst the individual subspecies. For example, the Aleutian Canada goose frequently sports a white neck-ring, much like that of a drake mallard. And the Cackling Canada goose, another subspecies, is only about a pound heavier (about 3 1/2 pounds) than a mallard duck, while the Giant Canada goose can weigh as much as twenty pounds and more.
Like all geese, Canada geese are grazers. The birds feed on grasses, aquatic plants, and agricultural crops such as wheat, soybeans, and corn. Insects are also a part of their diet, especially for the fast-growing goslings. It's also not unusual to observe Canada geese foraging for aquatic plants and other edibles in the water. Tipping their tails up and completely submerging their heads and necks into the water, Canada geese will feel around with their sensitive bills on the bottoms of wetlands for food. Natural strainers (lamellae), line the outside edges of their bills that assist in a number of activities such as straining water through foodstuffs, for cutting plant materials, and in preening their feathers.
It is believed that Canada geese mate for life. Indeed, the same pair will often return together to the same breeding ponds year after year. They are generally the first species of waterfowl to return in the springtime, mate, and begin to nest here in the Northland, usually around March and April.
Fiercely territorial, a nesting pair of Canada geese will not tolerate other nearby geese. Unlike ducks, both sexes assist each other in rearing their offspring. When the goslings hatch about a month after the last egg is laid, both the goose and the gander are constantly on the lookout for anything that could endanger the brood.
The latter parental characteristic is very evident when geese are captured for banding. Adult birds, generally the parents, are very protective of their broods. The large birds will sometimes hiss and strike handlers and banders with their beaks, claws, or wings.
But regardless of any inherent risks to the goose or their human handler, banding Canada geese leads to obtaining very valuable information. This includes such information as harvest, mortality, movements, and distribution of Canada goose populations across Minnesota and elsewhere throughout the continental flyways.
When the birds and their bands are recovered and reported -- usually by hunters who have harvested banded geese during the autumn hunting seasons -- better and more informed goose management decisions can be made, all of which add to our experiences as we get out and enjoy the great outdoors.
(Klemek is the DNR Area Wildlife Supervisor in Detroit Lakes. You can contact him at firstname.lastname@example.org)