Their body feathers may be either predominately grayish or a reddish brown, and their tails vary even more in color. In the upper mid-west as many as 58 variations in tail color are recognized, lumped into 4 broad categories of silver gray, intermediate gray, brown and red. Red-phased grouse become more prevalent in milder climates, and the gray birds are more abundant where winter climates are more severe.
Males tend to have the copper or chocolate colored band about twice as often as females. In some areas of the upper Midwest, Ruffed Grouse are more abundant in woodlots scattered through populated areas than in remote wilderness forests. They thrive best where forests are kept young and vigorous by occasional clear-cut logging, or fire, and gradually diminish in numbers as forests mature and their critical food and cover resources deteriorate in the shade of a climax forest.
Since the quality of grouse cover declines years following disturbance, repeated disturbance e. Ruffed Grouse response to man varies greatly across their range, depending upon their experiences. In New England and the East, they are usually quite elusive and difficult to approach. When the ground is bare of snow, Ruffed Grouse feed on a wide variety of green leaves and fruits, and some insects.
They have also been known to eat snakes, frogs and salamanders as well. Extensive feeding upon flower-buds in apple orchards caused Ruffed Grouse to be placed on the list of bountied animals in some New England states at one time. Ruffed Grouse are normally solitary in their social behavior. They do not develop a pair-bond between males and females, although there is usually at least one hen in the woods for every male.
Young birds, especially, collect in temporary, loose flocks in the fall and winter, but this is not equivalent to the covey organization of the quails and partridges. Male Ruffed Grouse are aggressively territorial throughout their adult lives, defending for their almost exclusive use a piece of woodland that is acres in extent.
Usually this is shared with one or two hens. 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.
Male grouse are extremely territorial and will agressively defend that territtory which can extend to as much as 20 acres. What Do Grouse Eat? The ruffed grouse has a varied diet, depending on the season. In the summer, seeds, insects, and fruits like blueberries, strawberries, and raspberries are it's main diet.
In the winter when these types of food are more scarce, the ruffed grouse mostly survives on the buds and catkins of trees and shrubs such as aspen, cherry, birch, ironwood and apple.
Females lay groups of eggs, known as a "clutch", in shallow nests made up of leaf litter. Incubation usually takes about 24 days. The newborn chicks leave the nest shortly after birth and will feed and stay with the hens until fully grown. It has large, triangular flippers, or pectoral fins.
Its tail, also called flukes or caudal fins, is broad six m wide from tip to tip! Unlike most other large whales, it has no dorsal fin. For a variety of reasons, including its rarity, scientists know very little about this rather large animal. For example, there is little data on the longevity of Right Whales, but photo identification on living whales and the analysis of ear bones and eyes on dead individuals can be used to estimate age.
It is believed that they live at least 70 years, maybe even over years, since closely related species can live as long. Unique characteristics. The Right Whale has a bit of an unusual name. Its name in French is more straightforward; baleine noire, the black whale. The American Eel Anguilla rostrata is a fascinating migratory fish with a very complex life cycle.
Like salmon, it lives both in freshwater and saltwater. It is born in saltwater and migrating to freshwater to grow and mature before returning to saltwater to spawn and die. The American Eel can live as long as 50 years. It is a long, slender fish that can grow longer than one metre in length and 7.
Males tend to be smaller than females, reaching a size of about 0. With its small pectoral fins right behind its gills, absence of pelvic fins, long dorsal and ventral fins and the thin coat of mucus on its tiny scales, the adult eel slightly resembles a slimy snake but are in fact true fish. Adult eels vary in coloration, from olive green and brown to greenish-yellow, with a light gray or white belly.
Females are lighter in colour than males. Large females turn dark grey or silver when they mature. The American Eel is the only representative of its genus or group of related species in North America, but it does have a close relative which shares the same spawning area: the European Eel.
Both have similar lifecycles but different distributions in freshwater systems except in Iceland, where both and hybrids of both species can be found. The American Lobster Homarus americanus is a marine invertebrate which inhabits our Atlantic coastal waters.
As an invertebrate, it lacks bones, but it does have an external shell, or exoskeleton, making it an arthropod like spiders and insects. Its body is divided in two parts: the cephalothorax its head and body and its abdomen, or tail. On its head, the lobster has eyes that are very sensitive to movement and light, which help it to spot predators and prey, but are unable to see colours and clear images. It also has three pairs of antennae, a large one and two smaller ones, which are its main sensory organs and act a bit like our nose and fingers.
Around its mouth are small appendages called maxillipeds and mandibles which help direct food to the mouth and chew. Lobsters have ten legs, making them decapod ten-legged crustaceans, a group to which shrimp and crabs also belong other arthropods have a different number of legs, like spiders, which have eight, and insects, which have six.
Four pairs of these legs are used mainly to walk and are called pereiopods. The remaining pair, at the front of the cephalothorax, are called chelipeds and each of those limbs ends with a claw.
These claws help the lobster defend itself, but also capture and consume its prey. Each claw serves a different purpose: the bigger, blunter one is used for crushing, and the smaller one with sharper edges, for cutting. The Barn Swallow Hirundo rustica is a medium-sized songbird, about the size of a sparrow. It measures between 15 and 18 centimeters cm in length and 29 to 32 cm in wingspan, and weighs between 15 and 20 grams g. Its back and tail plumage is a distinctive steely, iridescent blue, with light brown or rust belly and a chestnut-coloured throat and forehead.
Their long forked tail and pointed wings also make them easily recognizable. Both sexes may look similar, but females are typically not as brightly coloured and have shorter tails than males. When perched, this swallow looks almost conical because of its flat, short head, very short neck and its long body. Although the average lifespan of a Barn Swallow is about four years, a North American individual older than eight years and a European individual older than 16 years have been observed.
Sights and sounds: Like all swallows, the Barn Swallow is diurnal —it is active during the day, from dusk to dawn. It is an agile flyer that creates very acrobatic patterns in flight. It can fly from very close to the ground or water to more than 30 m heights. When not in flight, the Barn Swallow can be observed perched on fences, wires, TV antennas or dead branches.
Both male and female Barn Swallows sing both individually and in groups in a wide variety of twitters, warbles, whirrs and chirps. They give a loud call when threatened, to which other swallows will react, leaving their nests to defend the area. Freshwater turtles are reptiles, like snakes, crocodilians and lizards. They also have a scaly skin, enabling them, as opposed to most amphibians, to live outside of water.
Also like many reptile species, turtles lay eggs they are oviparous. But what makes them different to other reptiles is that turtles have a shell. This shell, composed of a carapace in the back and a plastron on the belly, is made of bony plates. These bones are covered by horny scutes made of keratin like human fingernails or leathery skin, depending on the species.
All Canadian freshwater turtles can retreat in their shells and hide their entire body except the Common Snapping Turtle Chelydra serpentina. This shell is considered perhaps the most efficient form of armour in the animal kingdom, as adult turtles are very likely to survive from one year to the next. Indeed, turtles have an impressively long life for such small animals. Most other species can live for more than 20 years. There are about species of turtles throughout the world, inhabiting a great variety of terrestrial, freshwater and marine ecosystems on every continent except Antarctica and its waters.
In Canada, eight native species of freshwater turtles and four species of marine turtles can be observed. Another species, the Pacific Pond Turtle Clemmys marmorata , is now Extirpated, having disappeared from its Canadian range. Also, the Eastern Box Turtle Terrapene carolina has either such a small population that it is nearly Extirpated, or the few individuals found in Canada are actually pets released in the wild.
More research is needed to know if these turtles are still native individuals. Finally, the Red-eared Slider Trachemys scripta elegans , has been introduced to Canada as released pets and, thus, is not a native species. Females tend to be slightly larger than males but are otherwise identical.
As its name implies, it is pale tan to reddish or dark brown with a slightly paler belly, and ears and wings that are dark brown to black. Contrary to popular belief, Little Brown Bats, like all other bats, are not blind.
Still, since they are nocturnal and must navigate in the darkness, they are one of the few terrestrial mammals that use echolocation to gather information on their surroundings and where prey are situated.
The echolocation calls they make, similar to clicking noises, bounce off objects and this echo is processed by the bat to get the information they need. These noises are at a very high frequency, and so cannot be heard by humans. Narwhals Monodon monoceros are considered medium-sized odontocetes, or toothed whales the largest being the sperm whale, and the smallest, the harbour porpoise , being of a similar size to the beluga, its close relative.
Males can grow up to 6. Females tend to be smaller, with an average size of 4 m and a maximum size of 5. A newborn calf is about 1. Like belugas, they have a small head, a stocky body and short, round flippers. Narwhals lack a dorsal fin on their backs, but they do have a dorsal ridge about 5 cm high that covers about half their backs. This ridge can be used by researchers to differentiate one narwhal from another. It is thought that the absence of dorsal fin actually helps the narwhal navigate among sea ice.
Unlike other cetaceans —the order which comprises all whales—, narwhals have convex tail flukes, or tail fins. These whales have a mottled black and white, grey or brownish back, but the rest of the body mainly its underside is white. Newborn narwhal calves are pale grey to light brownish, developing the adult darker colouring at about 4 years old. As they grow older, they will progressively become paler again. Some may live up to years, but most probably live to be 60 years of age.
Although the second, smaller incisor tooth often remains embedded in the skull, it rarely but on occasion develops into a second tusk. Tusks typically grow only on males, but a few females have also been observed with short tusks. The function of the tusk remains a mystery, but several hypotheses have been proposed. Many experts believe that it is a secondary sexual character, similar to deer antlers. Thus, the length of the tusk may indicate social rank through dominance hierarchies and assist in competition for access to females.
Indeed, there are indications that the tusks are used by male narwhals for fighting each other or perhaps other species, like the beluga or killer whale.
A high quantity of tubules and nerve endings in the pulp —the soft tissue inside teeth — of the tusk have at least one scientist thinking that it could be a highly sensitive sensory organ, able to detect subtle changes in temperature, salinity or pressure.
Narwhals have not been observed using their tusk to break sea ice, despite popular belief. Narwhals do occasionally break the tip of their tusk though which can never be repaired.
This is more often seen in old animals and gives more evidence that the tusk might be used for sexual competition.
Adult coho salmon have silvery sides and metallic blue backs with irregular black spots. Spawning males have bright red sides, and bright green backs and heads, with darker colouration on their bellies. The fish have hooked jaws and sharp teeth. Young coho salmon are aggressive, territorial and often vibrantly coloured, with a large orange anal fin edged in black and white. Its name comes from the partial webs between its toes.
Males and females are identical in rather plain brown or grey plumage although females are slightly larger.
The species can be difficult to distinguish from other small sandpipers. Semipalmated Sandpipers moult, or shed, their body feathers twice a year. The change to the greyish-brown fall-winter plumage usually starts on the breeding grounds and is completed after arrival on the non-breeding area.
The moult that takes place on the non-breeding area prior to spring migration gives them a slightly brighter more brown breeding plumage. Adults moult their flight feathers wings and tail gradually—retaining the ability to fly at all times—and only once per year, usually in the non-breeding area.
Some juveniles do not replace any flight feathers in their first winter, as these are quite new. Others, however, moult some of the outermost primaries outer wing feathers , which are important for flight and wear most rapidly.
One of the heaviest of North American owls, the Snowy Owl Bubo scandiacus stands nearly half a metre tall, with a wingspan of almost 1. As is the case with most diurnal birds of prey—those that are active during the day—the female is larger and heavier than the male. The average weight of the female is 2.
Adult males may be almost pure white in colour. Adult females are darker, their white feathers barred with dark brown. First-year birds of both sexes are more darkly marked than their adult counterparts. Immature males resemble adult females, and immature females are heavily barred and may appear dark grey when seen from a distance. The light coloration of Snowy Owls provides camouflage when the owls are perched on snow, but this advantage is lost in summer.
As spring approaches and the ground becomes bare, Snowy Owls move to sit on patches of snow or ice. No one knows whether they do this to camouflage themselves or whether they are merely keeping insects away or staying cool. In strong wind, Snowy Owls may seek shelter by crouching on the ground behind a windbreak, such as a pile of stones, snowdrift, or bale of hay. Of the 19 species of raptors, or birds of prey, in Canada, three are Accipiters. Accipiters are small to medium-sized hawks of swift flight that occur around the world.
Accipiters can be distinguished from other types of hawks by their flight silhouettes see sketch. Like the buteos e. In contrast, the wings of another group of hawks, the falcons, such as the Kestrel or Sparrow Hawk Falco sparverius , are pointed. All accipiters generally have similar colouring, small heads, long tails, and short rounded wings.
The female of each species grows larger than the male.
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