The vent is then everted by pressing gently down on the abdomen with the thumb of the left hand near the vent. Simultaneously place the first finger and thumb of the right hand close together on the opposite side of the vent and slowly separate with a gentle but firm pressing motion, stretching and everting the cloaca to expose the penis if the gosling is male.
Mature birds that is, birds over the age of 7 months can be identified by physical examination. The identification is made easier if two people are available.
One method of exposing the penis is by pushing back the tail towards the head with one hand and exerting a steady downward pressure on the abdomen with the other. The vent will then be everted and the organ exposed. The penis, spiral shaped and white, is just over 1 cm long in immature birds but up to 4 cm long in mature ganders. The illustrations of the exposed reproductive organs of an immature male, a mature male and a maturing female will assist in sex identification:.
The characteristics listed in Table 2 may also help you to distinguish sexes:. Mark birds according to their sex using leg bands, web punching, or wing bands. Egg production, incubation and sex identification of geese. More topics in this section.
Goose egg production The main egg-laying period for geese is in the spring, commencing about August or September. As geese usually lay in the morning, collect eggs late in the morning to reduce the chance of egg breakages, and collect eggs at least four times a day. Because most eggs are laid early in the morning, it is best not to give geese access to swimming facilities until later in the morning, otherwise eggs may be lost.
As mentioned earlier, swimming improves the condition of geese generally and helps to keep them clean, which in turn helps to keep eggs clean. Geese usually lay a clutch of 12—15 eggs and then go broody. Early onset of egg production can be encouraged by the following: Genetic selection and cross-breeding. Chinese breeds are better egg producers than Toulouse or Emden breeds, but their smaller body is a disadvantage.
Cross-breeding the Chinese breed with either Toulouse or Emden produces breeding stock of acceptable egg production and carcase. Males begin mating at three years of age, and females begin mating when they are three or four years old. Breeding season for Canada geese is between February and April, depending on the climate. Geese mate once a year.
Canada geese have elaborate courtship behaviors. The female chooses a mate based on his displays and how well she believes he can protect her. Canada geese are monogamous and mate for life. If one of the pair dies, the surviving goose will mourn and may eventually find another mate.
Canada geese return to the same nesting sites every year. Their nest sites are usually located in an elevated area on an island, on top of a small hill, in bushes, or in a raised area around a lake. Adult Canada geese have grayish brown wings, backs, sides, and breasts; black tails, feet, legs, bills, and heads; and long black necks with distinctive white cheek patches.
Males tend to be larger than females, though their coloration is identical. Goslings are light yellow with greenish-gray heads when they hatch. As they mature, they become darker until they resemble the adults about the time they can fly, about 70 days after hatch. The average life span of a Canada goose is years. There are reports of geese living more than 30 plus years in the wild and an isolated case of a Canada goose living over age 40 in captivity. Most Canada geese pair with a mate at age three, though some begin this process at two years.
Pairs usually stay together for life. If one member of a pair dies, the other goose usually finds another mate within the same breeding season. In Indiana, flocks break up into pairs for nesting in mid- to late February. Nesting activities begin from mid-March through late April. Ideal nesting sites for Canada geese are any place that provides concealment near water, including: islands; muskrat houses; artificial nesting structures; vegetation along shorelines; at the base of mature trees; under shrubs; in thick aquatic vegetation such as cattails; in flower boxes and landscaping in urban and suburban areas; and in doorways or on structures, especially rooftops, in urban areas.
Once nesting has begun, the male and female will both defend the nest. The female lays eggs about every 1. Once all the eggs are laid, incubation begins.
The eggs are incubated for 28 days. The average clutch size is 5 eggs, though eggs is possible. All eggs in the nest hatch at the same time. The adults then lead the goslings away from the nest, within 24 hours of hatch. If the nest is destroyed before the eggs hatch, the pair will generally begin re-nesting at or very near the original nesting site. Canada geese have a greater tendency to re-nest if the original nest is destroyed earlier in the nesting season.
Both adults, especially the male, vigorously defend their broods for approximately weeks after hatch. This defense diminishes as the goslings grow older and begin to be able to fly. It is common to see several broods of goslings together, termed gang broods, during this time.
Gang broods may range from 20 to goslings following just a few adults. Gang broods are more common in areas of high nest density. Canada geese are grazers and chiefly vegetarian, though fish or invertebrates have been reported in their diets in small amounts.
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