They may also creep slowly when crossing snowfields or if they sense a predator is nearby. They rarely swim or dive, and do not often fly unless trying to escape from a predator or survey an area. Willow ptarmigan usually bathe in dust, sand, dry dirt or snow by fluffing their feathers up and using their wings to flip sand, dirt or snow onto their backs. Frolicking is a form of play that occurs in willow ptarmigan family groups, or sometimes entire flocks.
The birds crouch low to the ground and jump around erratically while flapping their wings. Andreev, ; Hannon and Martin, ; Johnsgard, ; Nash, For this reason, it is difficult to obtain any reliable information for their population density and territory size. In Canada, estimates of population density range from 1 adult per square mile to as many as 8 adults per square mile.
A study of Scandinavian willow ptarmigan populations determined territory sizes ranging from 6. Johnsgard, ; Steen, et al. Several different communication sounds have been observed in willow ptarmigan and at least 11 different calls have been observed. Both sexes have territorial calls that are similar. These sounds may also be used to stay in contact with a mate or offspring. Males give calls that are noticeably stronger and more modulated than females' calls. Like all birds, willow ptarmigan perceive their environments through auditory, visual, tactile and chemical stimuli.
Hannon, However, during the winter their diets consist of less protein, but is much more abundant in fiber and carbohydrates.
During the summer months, willow ptarmigan consume a variety of different foods, including willow Salix species buds, grass shoots, flowers, seeds, berries including Vaccinium angustifolium , Vaccinium oxycoccos , Vaccinium vitis-idaea and Empetrum nigrum , insects, caterpillars and beetles.
As winter approaches and the availability of insects and caterpillars decreases, the amount of berries, seeds and buds consumed increases.
During the winter, food is often more difficult to find and willow ptarmigan must dig through the snow to find sustenance. Their winter diet is composed mainly of willow buds and twigs, as well as some birch Betula species. The adaptation of digestive enzymes and intestinal microflora to provide nutrition and energy from a single food source is unusual; however, studies suggest that willow ptarmigan are well adapted for obtaining nutrition and energy from a variety of different diets, and that although willow is a primary food source, the species is capable of deriving their nutrition from other sources.
Contrary to North American willow ptarmigan populations, Scotland's red grouse population a subspecies of willow ptarmigan has a diet consisting of mainly heather. It has also been found that during nesting season, red grouse tend to select for heather rich in nitrogen and phosphorus. There are typically two peak feeding times for willow ptarmigan during the winter months. During the morning, feeding occurs for approximately 2 hours, with the same time period being followed for evening feeding.
It has been observed that as the daylight hours increase, feeding time also increases. Willow ptarmigan chicks consume mainly caterpillars, insects, flowers and seeds, largely due to their need for a diet high in protein in order to facilitate extremely fast growth. Willow ptarmigan usually feed in flocks. The size of the flock generally increases or decreases depending on the availability and amount of food present.
Willow ptarmigan have many known predators, many of which prey solely on eggs or willow ptarmigan chicks. It has been observed that predation on willow ptarmigan nests is much more common by avian predators than by mammalian predators.
In response to predators, willow ptarmigan will often freeze in a crouching position with their heads lowered and extended. They may perform a diversionary walk to distract predators from the nest or their mate, and may also feign injury by moving slowly along the ground while quivering their wings. This movement makes the ptarmigan appear as though it is dragging itself. One of the most important anti-predator adaptations of willow ptarmigan is plumage that seasonally changes with the environment.
As the snow melts and the surroundings change color, moulting from white to mottled brown occurs very quickly to ensure optimal camouflage. The same pattern is followed for each seasonal change, with the plumage rapidly changing to match the environment. It has also been observed that female willow ptarmigan will choose feeding areas in which they will be better camouflaged rather than ones that offer better nutritional benefits.
Several known predators of North American willow ptarmigan populations include: hooded crows , ravens , magpies , red foxes , pine martens , mink , short-tailed weasels , least weasels , gulls , northern harriers , golden eagles , bald eagles , rough-legged hawks , gyrfalcons , peregrine falcons , northern goshawks , snowy owls , wolverine , wolves , Arctic foxes , lynx and polar bears. Known predators of Scottish red grouse populations include: red foxes , wildcats , golden eagles , hen-harriers , sparrow-hawks and common buzzards and rough-legged buzzards.
Merlins and short-eared owls have been known to kill young red grouse up to the age of about 8 weeks however, they are not important predators for adult red grouse. Hannon and Martin, ; Pedersen, et al. Willow ptarmigan are predators of various insect and beetle species. They may be infected with flukes Trematoda species , tapeworms Cestoda species , roundworms Nematoda species and ectoparasites. Many parasites are thought to decrease the body weight of willow ptarmigan, which can lead to death if the weight loss is severe enough.
Although this has not been formally observed in North America, populations of red grouse in Scotland have experienced significant decline due to body parasites. As well as being a predator to many invertebrates, willow ptarmigan are also prey to a number of larger bird and mammal species, including hooded crows , ravens , magpies , red foxes , gyrfalcons , wolverines , wolves and Arctic foxes.
Hannon and Martin, ; Holmstad, et al. Willow ptarmigan are extremely popular upland game birds in North America and Europe and are regularly used for sport. A subspecies of willow ptarmigan, Scottish red grouse, have particularly important economic value in Scotland.
The abundance of red grouse is often a determining factor in land value and revenue, and thus employment and use of the land. The decline of the Scottish red grouse population has lead to loss of revenue in the Central Highlands. Barnes, There are no known adverse effects of willow ptarmigan on humans.
Aniskowicz, Willow ptarmigan are extremely widespread and their conservation status is of least concern. However, as of , they were classified as critically imperiled in the province of Alberta, Canada.
Several new possible threats to ptarmigan populations have emerged in recent years. Although ecotourism has not directly altered ptarmigan populations, it has inadvertently contributed to the destruction of already fragile habitats that support this species. Pollutants are also becoming a more serious problem to many Arctic populations, including willow ptarmigan.
The Scottish red grouse population has shown significant decline in recent years. This is thought to have occurred primarily due to the reduction of heather abundance which are a main food source for red grouse , caused by afforestation and farming. Wainwright Inupiat obtained Rock Ptarmigan on land when encountered; hunters did not actively seek out the birds on the ice [83]. The bird was also hunted by Clyde Inuit March to December, but once the snow came, the white plumage made the flocks difficult to locate [72].
Yukon hunters caught Rock Ptarmigan by setting nets of babiche and sinew among willows on the sides of mountains.
Hunters would easily herd the birds into the nets because ptarmigan waddle in winter rather than fly [68]. Rock Ptarmigan was prominent in the Inuit diet. Women hid snares of braided deer sinew among willows. They also drove the birds into nets that had been set on the snow [57]. Labrador Inuit trapped these birds with stationary snares or shot them with blunt arrows [17, 82]. Belcher Island Inuit reportedly ate the flesh of Rock Ptarmigan raw or cooked, but the intestines were usually consumed raw [84].
White-tailed Ptarmigan are rarely mentioned in ethnographic, possibly because they were not differentiated from other ptarmigan. However, this slightly smaller species was likely harvested and consumed by multiple cultures in British Columbia, southern Yukon, and southeastern Alaska.
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Jenness D: Bread from the Waters. In: The People of the Twilight. Hull, Quebec: Canadian Musem of Civilization; Anthropological Publications Vol. When in flight, it has a wedge-shaped tail, with longer feathers in the middle. While females may be a bit smaller, both sexes are very similar. The size of an adult raven may also vary according to its habitat, as subspecies from colder areas are often larger. A raven may live up to 21 years in the wild, making it one of the species with the longest lifespan in all passerine birds.
Both birds are from the same genus order of passerine birds, corvid family —like jays, magpies and nutcrackers, Corvus genus and have a similar colouring. But the American Crow is smaller with a wingspan of about 75 cm and has a fan-shaped tail when in flight with no longer feathers.
Their cries are different: the raven produces a low croaking sound, while the crow has a higher pitched cawing cry. While adult ravens tend to live alone or in pairs, crows are more often observed in larger groups. The Atlantic Cod Gadus morhua is a medium to large saltwater fish: generally averaging two to three kilograms in weight and about 65 to centimetres in length, the largest cod on record weighed about kg and was more than cm long!
Individuals living closer to shore tend to be smaller than their offshore relatives, but male and female cod are not different in size, wherever they live. The Atlantic Cod shares some of its physical features with the two other species of its genus, or group of species, named Gadus. The Pacific Cod and Alaska Pollock also have three rounded dorsal fins and two anal fins. They also have small pelvic fins right under their gills, and barbels or whiskers on their chins. Both Pacific and Atlantic Cod have a white line on each side of their bodies from the gills to their tails, or pectoral fins.
This line is actually a sensory organ that helps fish detect vibrations in the water. The colour of an Atlantic Cod is often darker on its top than on its belly, which is silver, white or cream-coloured.
In rocky areas, a cod may be a darker brown colour. Cod are often mottled, or have a lot of darker blotches or spots.
It can weigh up to 63, kilograms and measure up to 16 metres. Females tend to be a bit larger than males — measuring, on average, one metre longer. Its head makes up about a fourth of its body length, and its mouth is characterized by its arched, or highly curved, jaw. Its skin is otherwise smooth and black, but some individuals have white patches on their bellies and chin.
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. Region: Arctic.
Destinations: Greenland, Svalbard. Diet : Berries, leaves, buds, seeds, flowers. Juvenile birds will also eat insects. Ptarmigan migration flocks can number in the hundreds. Outside of migration and breeding season they continue to live together in flocks numbering in the dozens for protection, but these flocks are usually segregated by the sexes. Males both display for females and show aggression towards other males through their combs. Males take a big risk during mating season — their feathers remain winter white until after mating is complete.
The nests are built on sparsely vegetated tundra. Up to 13 average 6 chicks are born per clutch. Unlike the males, the females moult to their summer feather colours in time for mating season.
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