This sound is made by beating his wings against the air to create a vacuum, as lightning does when it makes thunder. The drumming stage selected by a male is most likely to be about inches above the ground, in moderately dense brush, usually 70 to stems within a 10 ft.
Across much of the Ruffed Grouse range there are usually mature male aspens within sight in the forest canopy overhead. In the spring, drumming becomes more frequent and prolonged as the cock grouse advertises his location to hens seeking a mate. Listen to an example at the top of this page. Courtship is brief, lasting but a few minutes, then the hen wanders away in search of a nest site, and there is no further association between the male grouse and his mate — or the brood of chicks she produces.
Nests are hollowed-out depressions in the leaf litter, usually at the base of a tree, stump or in a clump of brush. The nest is usually in a position which allows the hen to maintain a watch for approaching predators. Sometimes hens will nest under logs or in brush piles, but this is less common, and a dangerous location. A clutch usually contains 8 to 14 buff colored eggs when complete. Eggs are laid at a rate of about one each day and a half, so it may take 2 weeks for a clutch to be completed.
Then incubation, which usually commences when the last egg is laid, takes another 24 to 26 days before the eggs hatch. A nest has to be placed so that it will not be discovered by a predator during a period of at least 5 weeks. The chicks are precocial, which means that as soon as they have dried following hatching they are ready to leave the nest and start feeding themselves.
They begin flying when about 5 days old, and resemble giant bumble bees in flight. The hen may lead her brood as far as 4 miles from the nest to a summer brood range during its first 10 days of life.
Although grouse broods occasionally appear on roadsides, field edges or in forest openings, these are hazardous places for young grouse to be, and broods survive best if they can remain secure in fairly uniform, moderately dense brush or sapling cover. The growing chicks need a great deal of animal protein for muscle and feather development early in life. They feed heavily on insects and other small animals for the first few weeks, gradually shifting to a diet of green plant materials and fruits as they become larger.
That is a 38 to 46 fold increase in weight. At 17 weeks of age, a Ruffed Grouse is almost as large and heavy as it will ever be. Biologists and others who want to age Ruffed Grouse rely upon certain peculiarities of the molt of the primary flight feathers. The booklet explains this aging procedure. Following the first complete molt by a 14 to 15 month old adult grouse, there are no known physical characteristics which reliably identify the age.
When about 16 to 18 weeks old, usually in September or October, the young grouse passes out of its period of adolescence and breaks away to find a home range of its own. This is the second and last time that Ruffed Grouse are highly mobile. The young males are the first to depart, when they range out seeking a vacant drumming territory, or activity center, where they can claim a drumming log.
Most young males find a suitable site within 1. Many young cocks claim a drumming log by the time they are 20 weeks old; and once they have done so, most will spend the remainder of their lives within a to yard radius of that log.
Young females begin leaving the brood one or two weeks later than their brothers, and they normally disperse about three times as far. Occasionally a hen and her brood will remain together as late as mid-January, but this is unusual, and most groups of grouse encountered in the fall and winter are composed of unrelated individuals who gather together temporarily to share a choice food resource or piece of secure cover.
After all, young grouse in their first fall have never been confronted by something that can be seen through but not flown through, such as glass! Ruffed Grouse normally have a short life span. From a brood of 10 or 12 hatched in late May or early June, usually 5 or 6 will have died by mid-August. So from chicks hatched in late spring, about normally survive to early autumn, survive to the following nesting season, 80 are alive a year later, 36 live to breed a 3rd time, 16 may breed a 4th time.
One out of chicks hatched may live as long as 8 years. Most Ruffed Grouse die a violent death to provide a meal for one of a number of meat-eating predators, for in the natural scheme of things, Ruffed Grouse are one of the first links in a complex food chain. Some also die from disease and parasites, or from exposure to severe weather, or accidentally by hitting trees or branches while in a panic flight after being frightened. Across the major portion of the Ruffed Grouse range, the winged predators or raptors are most efficient at taking these birds.
Although the goshawk is certainly the most efficient of all grouse predators, they are relatively uncommon and the horned owl probably kills more grouse across their range annually than any other predator. Range The ruffed grouse lives in deciduous forests that exist across Canada and from Alaska in the north and northern Georgia in the south.
Download a printable version of this page See more of our Animal of the Month features for kids. Share this page. Topics About Can Geo. Canada Charting Change. Commemorate Canada. Explore Podcast. Gear Reviews. Map archive. Ocean Bridge.
Ocean Supercluster. The Franklin Expedition. The North. The Polar Blog. The Terror. Canadian Geographic Challenge. The National Bird Project. Classroom Energy Diet Challenge. Energy IQ. Canada's Coolest School Trip. A Developing World. Canadian Hydropower Interactive Map. It has barred flanks and a black ruff around its neck. It has a short, pointed bill and a long, square, flat tail. Diet In the summer, the ruffed grouse eats seeds, and fruits like thorn apples, blackberries, blueberries, and strawberries.
Life Cycle The male ruffed grouse attracts mates and defends his territory by drumming! He perches on a drumming post, usually a log, mound or stone, and cups his wings and beats them against the air. This produces a drumming sound! In fact, the ruffed grouse is sometimes called the drummer.
The male will puffs out his ruff and fans out his tail in a visual display designed to either attract a mate or warn off an intruder.
0コメント