2. Where did the Canada geese that nest in Iowa come from?
Giant Canada geese nested throughout all of Iowa before the 1800's.  Habitat loss and unregulated harvest caused the nesting population to disappear from the state by 1910.  A program to restore the population of giant Canada geese was initiated in northwest Iowa in 1965.  The geese used for this restoration program were descendants of wild giant Canada geese that had been captured in Iowa and southern Minnesota during the latter half of the 1800’s.  Settlers in northern Iowa and southern Minnesota frequently captured these geese during mid-summer when the adults were molting and the young could not yet fly.  (Biologists still capture geese this way to band them each year.)  Flocks of these large geese were raised on many pioneer farms for food as well as for their feathers, particularly their soft insulating down.

3. How big are the giant Canada geese that nest in Iowa?
Adult female giant Canada geese average about 11 pounds whereas adult males average about 12 pounds.  Giant Canada geese weighing up to 16 pounds have been taken by hunters in several Midwest states but they are uncommon.

4. At what age do Canada geese begin to nest?
Between 20 and 30% of the giant Canada geese that are found in Iowa will nest when they are 2-years old. The remainder will not nest until 3-years old.  The interior and small Canada geese that nest around Hudson Bay most often do not nest until they are 4 years old.

5. What do the Canada geese that aren’t old enough to nest do during the spring and summer?
One and two year old geese, also referred to as nonbreeding geese, often return to the general area where they first learned to fly for a few weeks early in the spring, but then they often move on exploring new habitat.  Many of these nonbreeders wander north, some as far north as Manitoba and the shore of Hudson Bay, where they join other groups of nonbreeding geese to molt.  After wandering for 2 years, the female geese still return to their natal area when they start to nest. 

6. How does a goose choose a nest site?
When a female goose reaches breeding age, she most often returns to the general area where she first learned to fly.  It is there that she makes her first nesting attempt.  This behavior is called homing.  Her mate essentially goes wherever she leads him.  Adult geese almost always return (home) to the place that they nested the previous year, especially if they successfully hatched a clutch.  Geese generally look for a pond that offers a "safe" nesting site, a nearby feeding site, and good brood-rearing areas within walking distance (several miles).

7. When do geese usually begin nesting during the spring? 
Geese usually begin nesting in Iowa between mid-March and mid-April, depending upon how old they are and where they are in the state.  Geese that have nested before usually begin nesting earlier than first-time nesters.  Geese nesting in southern Iowa usually start 2 weeks earlier than geese nesting in the northern counties.

8. How many eggs do Canada geese usually lay in one nest?
The number of eggs laid by one goose in a nest can range from 1 to 10, but the average for giant Canada geese is between 5 and 6.  The goose lay’s one egg per day.  If more than one goose is laying eggs in a nest, as sometimes occurs when geese are nesting close to each other (such as on an island), occasionally 15 or more eggs will be found in a nest.  These nests, which are referred to as “dump nests” because 2 or more hens are laying or “dumping” eggs in them, are seldom incubated by any of the geese that laid eggs in them. 

9. How long does it take the eggs to hatch?
The process of sitting on the eggs and keeping them warm so they develop properly and eventually hatch is called incubation.  The female goose begins incubating the eggs the day last egg is laid.  The goose normally incubates the eggs for 28-30 days before they hatch.

10. What causes a nest to fail to hatch?
Geese are very tenacious nesters and actively defend their nests from predators.  Despite this behavior, goose nests fail to hatch for several reasons, the most common being abandonment, flooding, or predation.  Nests may be abandoned or deserted because the goose is disturbed too often by other geese, people, or predators.  In some instances, the female goose may be killed by a predator.  Geese like to nest on muskrat houses and islands and frequently loose their nests to flooding when river and marsh water levels rise as a result of spring downpours.  Many predators will eat goose eggs, including mink, skunk, raccoon, fox, and coyote.  Predation is most common when geese are laying their eggs.  Once the eggs are laid, the goose is near the nest nearly 24 hours a day, so it is more difficult for predators to steal eggs.  Geese also tend to choose predator-safe nesting sites such as islands and muskrat houses, which improves their chances of hatching a clutch.  If a nest is lost during laying or the first few days of incubation an adult pair of geese may attempt to renest, but renesting, especially later in the spring is uncommon.

11. How many goslings in an average size brood survive long enough to fly?
It normally takes goslings 9 to 10 weeks to mature enough and develop flight feathers sufficient to enable them to fly.  During those weeks, they are exposed to a multitude of hazards including exposure from inclement weather, disease, accidents, and predation.  Predators, including mink, raccoons, fox, coyotes, snapping turtles, owls, hawks, and even large fish take a toll on the young goslings. On the average, 3-4 goslings in the brood will reach flight stage.

12. What do geese eat?
During the spring and summer geese, including the goslings, feed primarily the young, growing shoots of grasses and some herbaceous plants such as clover and alfalfa.  Although geese will feed in about any grassland, they prefer grasslands with short plant growth such as pastures, mowed hayfields or lawns and newly sprouting crop fields because they can more easily see any approaching predators.  In most cases, these feeding sites are close to the water’s edge so the goslings can quickly escape to the water if a predator approaches.  In the fall and winter, geese will switch to a diet that is primarily comprised of grains such as corn, soybeans, milo, barley and wheat.  Harvested crop fields that are not moldboard plowed usually have ample waste grain on which the geese can feed.

13. How can I attract geese to my pond?
In short, by providing good goose habitat.  Good habitat includes a safe nest site such as an island, a nest structure or a muskrat house, a loafing log or platform near the nest site for the gander to loaf on, and some short grass, possibly mowed, near the water’s edge for the brood and the adults to graze and loaf on.  For information on pond, island and nest structure designs, see Nest Structures for Ducks and Geese(a U.S.G.S. -- Northern Prairie Science Center site). 

14. Canada geese are causing problems on my property.  Who should I contact to get help controlling the geese?
Contact the DNR’s Wildlife Management Biologist for the county in which you are experiencing the problems.   For a listing of management biologists Click Here.

15. If most of the Canada geese harvested in Iowa are giant Canada geese, why are our hunting seasons shortened or bag limits reduced.  Isn’t the giant Canada goose population increasing?
     Waterfowl hunters in Iowa harvest Canada geese from 3 of the 11 races of Canada geese that are found in North America: giant Canada geese (Branta canadensis maxima), interior Canada geese (B. c. interior) and Richardson’s Canada geese (B. c. hutchinsii).  In some cases, these races are further divided into subpopulations for management purposes.  For example, the Eastern Prairie Population (EPP) and Mississippi Valley Population (MVP) are subpopulations of interior Canada geese.  Giant Canada geese, the largest of the 11 Canada goose races (9+ lb.), nest in southern parts of the Canadian provinces and from the Midwest to the Atlantic coast.  EPP and MVP Canada geese, subpopulations of the interior race of Canada geese (6-9 lb.), nest on the west and south sides of Hudson Bay.  Tall Grass Prairie Population (TGPP) Canada geese are comparatively small geese (<6 lb.), often referred to as "hutchies", that nest in the Arctic on Baffin Island. These geese are noticeably smaller than either the giant or interior races and can be easily identified in the field.  With the exception of Giants, these groups of geese were named during the mid 20th century for their primary wintering sites: MVP for the lower Mississippi Valley, EPP for geese that wintered around Swan Lake in MO and TGPP for the small Canadas that wintered in the tall grass prairie region that stretches from Iowa to Louisiana.
      Giant Canada goose populations are increasing, but the populations of some of the other races of geese are stable or declining.  The Migratory Bird Treaty and U.S. Fish and Wildlife Service policy require that all subpopulations be maintained as viable levels.  Consequently, hunting regulations must be adjusted to control the harvest of the subpopulations of geese that are below their objective levels.  For more details on Canada goose harvest management in Iowa, see (link to Canada Goose Harvest Management In Iowa).

16. Where are the areas that are closed to Canada goose hunting and how large are they?
Maps of areas closed to Canada goose hunting.

17. How long will the area that is closed to Canada goose hunting have to remain closed?
Some part of the area that is presently closed to Canada goose hunting will very likely have to remain closed because Canada goose biology and behavior makes them susceptible to over harvest given current hunting pressure.  All Canada goose closed areas are eventually reduced from their original size.  Some closed areas have been reduced to less than 40 square miles in size.  Protection from over harvest, however, is critical to sustaining Canada goose populations and providing long-term recreational opportunities.  For additional information regarding Iowa's Canada goose management Click here.

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