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OUT -OF -DOORS Page 3 of 5
<br />Canada Goose nest success typically ranges from 60 to 80 %. Four goslings are hatched per
<br />successful nest. Nests are lost to mammalian (coyote, fox, skunk, and raccoon) and avian predators
<br />(crow, raven, and large gulls), to flooding, and to desertion. The latter is seldom due to human
<br />disturbance, but rather to interference by adjacent territorial pairs.
<br />Once the young have hatched, the family abandons the nest site and travels, sometimes 5 or more
<br />miles, to a suitable brood - rearing site. Sites used by geese with their young are typically large (more
<br />than 10 acres) open -water wetlands and lakes, or slow moving rivers. Common characteristics of
<br />brood concentration sites, are clean (no driftwood or other debris) shorelines with low grasses, free of
<br />thick shrubs. Here, families of geese join together to graze on rapidly growing grasses and forbs. Like
<br />all grazing animals, geese have developed flocking (herding) behaviors, where the "many eyes mean
<br />better predator detection" and "better to be 1 of 100 than 1 of 1 if a predator attacks" principles apply.
<br />In a nutshell, Canada geese select open, grassy shorelines where visibility is good, food is abundant,
<br />and predator escape cover (open water) is only a short run away.
<br />Five weeks after the young hatch, the female loses her flight feathers and enters the molt period.
<br />The male molts 4 to 10 days after his mate. Both remain flightless until the young can fly, at 9 to 10
<br />weeks of age. Because of the energy and nutrients needed to replace flight feathers and for the gosling
<br />to grow from fist -sized to nearly full grown geese in less than 10 weeks, large quantities of forage
<br />must be consumed. If the source is an agriculture crop or a golf course, the resulting damage done to
<br />these areas and the goose droppings are frequently unwanted.
<br />Once on the wing again, in late July in Minnesota, the birds remain in families and the family
<br />groups that molted together remain together. These "subflocks" feed in the same fields and roost on
<br />the same open - shoreline lakes until they migrate. Moreover, these "subflocks" appear to remain intact
<br />during migration and on the wintering grounds. In this manner, the young geese learn the local
<br />environment and migratory routes from their parents, or if both parents die, from the other adult
<br />members of the "subflock ". This non - random movement behavior explains why geese stop at specific
<br />spots each year, and why wildlife managers have been able to provide for increasing numbers of
<br />geese by improving food resources along the migration routes.
<br />In fall, when a strong, high air pressure system follows a well developed low system, a cold front
<br />will sweep across the plains, leaving a blanket of snow behind. If the snow is deep enough (5 inches
<br />or more), the geese will wait out the storm, and when the sky clears and the wind is strong from the
<br />northwest, they will migrate south. Records from banded geese, particularly neckbanded ones,
<br />indicate that the migration flight is non -stop for 600 miles or so. During mild winters with little snow,
<br />such as this winter, many birds do not migrate. Presumably, this behavior permits those pairs to be
<br />the first to return and secure their breeding territories. In spring, the situation is the same except that
<br />migrations north occurs when a strong low follows a high pressure system.
<br />Winter is a relatively quiet time for Canada geese; families and subflocks continue to squabble
<br />over the best feeding and roosting sites, but once patterns are established, they change little until late
<br />winter. The birds normally fly from roosting to feeding sites about 8AM, feed and return within an
<br />hour or two, and preen and sleep until about 3PM. They then fly again to the feeding areas and return
<br />to the water to roost at dusk. During periods of extreme cold, 1OF or below, when the energy gained
<br />from feeding is less than that expended in securing food, most birds remain at the roost. During these
<br />times, energy is conserved by sitting on the snow, pulling the feet up into the flank feathers, and
<br />placing the bill under the scapular feathers on the back. While it is easy to feel sorry for the birds
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