Mallards are one of the most recognizable ducks in the world. The male birds have special colorful plumage during the spring and summer breeding season that helps them attract females. Their heads and necks are bright green, and at the base of their neck is a white ring. Breeding male mallards also have a dark brown chest, and the sides and most of the wings are gray.
The tail is white and black, and the bill is yellow. In contrast, females and non-breeding males do not have showy feathers.
The females are mottled tan and brown. The head is a lighter tan with dark streaks near the crown and eyes. The bill has an orange tint with dark markings. Non-breeding males look similar to the females, except they have a yellowish bill. All mallards have a blue speculum that is visible when the birds are in flight. The speculum is a distinctive patch of color on the wing near the shoulder, which often helps identify the species. On mallards, the speculum is purplish-blue and outlined in white.
These ducks are common throughout the continental United States and are a non-native introduction to the Hawaiian Islands. Two populations of mallards exist in Hawaii; one group is a winter visitor and the other stays year-round. Mallards are often seen swimming around ponds, marshes, and even man-made water sources, such as pools and fountains.
Mallards are foragers and will eat a wide variety of foods. The ducks prefer to forage in shallow water, where they can dip their heads down to reach aquatic plants.
They will also eat animal matter, including insect larvae, earthworms , and snails. It's corkscrew shaped and about 2 cm long or roughly three-fourths of an inch. It's outside his body, which is like other ducks, but different than most birds. In those other species, the gentlemen's equipment is generally inside his body to make flying easier. They mate many times, although exact numbers are unknown. Once in a while, a fellow who can't find a girl will become friendly with another's.
Having his equipment on the outside makes it easier for him to accomplish his goal, even if the girl is not that agreeable. So, a brood of ducklings could have multiple daddies. They pair up in October or November. The boys' feathers get exceptionally green on their heads to impress the girls. Couples stay together all winter and come spring, they go about making ducklings, and then the guys go on their way, and might find new mates next season.
April is in the middle of the season for a reason mating that runs from March to late May. A nice cozy place on dry land with overhanging grass or boughs that is close to water.
To add the zest of variety, mallards sometimes make their love nest in farm fields, especially where the alfalfa grows. But they also like winter wheat, barley, flax and oats.
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. 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. Of the species of woodpeckers worldwide, 13 are found in Canada.
The smallest and perhaps most familiar species in Canada is the Downy Woodpecker Picoides pubescens. It is also the most common woodpecker in eastern North America.
This woodpecker is black and white with a broad white stripe down the back from the shoulders to the rump. The crown of the head is black; the cheeks and neck are adorned with black and white lines.
Male and female Downy Woodpeckers are about the same size, weighing from 21 to 28 g. The male has a small scarlet patch, like a red pompom, at the back of the crown. The Downy Woodpecker looks much like the larger Hairy Woodpecker Picoides villosus , but there are some differences between them. The Downy is about 6 cm smaller than the Hairy, measuring only 15 to 18 cm from the tip of its bill to the tip of its tail.
Woodpeckers are a family of birds sharing several characteristics that separate them from other avian families. Most of the special features of their anatomy are associated with the ability to dig holes in wood. The straight, chisel-shaped bill is formed of strong bone overlaid with a hard covering and is quite broad at the nostrils in order to spread the force of pecking.
A covering of feathers over the nostrils keeps out pieces of wood and wood powder. The pelvic bones are wide, allowing for attachment of muscles strong enough to move and hold the tail, which is important for climbing. Another special anatomical trait of woodpeckers is the long, barbed tongue that searches crevices and cracks for food.
The salivary glands produce a sticky, glue-like substance that coats the tongue and, along with the barbs, makes the tongue an efficient device for capturing insects. Signs and sounds. As early as February or March a Downy Woodpecker pair indicate that they are occupying their nesting site by flying around it and by drumming short, fast tattoos with their bills on dry twigs or other resonant objects scattered about the territory.
The drumming serves as a means of communication between the members of the pair as well. Downys also have a variety of calls. They utter a tick, tchick, tcherrick , and both the male and the female add a sharp whinnying call during the nesting season. Hatchlings give a low, rhythmic pip note, which seems to indicate contentment. When a parent enters the nest cavity, the nestlings utter a rasping begging call, which becomes stronger and longer as the chicks mature. Everyone who has visited the coast is familiar with gulls, those graceful, long-winged birds that throng the beaches and harbours and boldly beg for scraps.
The gulls are a family of birds that live mainly at sea, either along the shore, or out in the ocean itself. Worldwide, there are more than species of birds that live either partially or exclusively at sea, and these are generally known as "seabirds. The table below lists the 14 families of marine birds and the approximate number of species in each the exact number of species is continually being revised as genetic research reveals that some very similar-looking birds are so different in their genetic makeup that they constitute different species.
All species belonging to the albatross, auk, frigatebird, gannet, penguin, petrel, and storm-petrel families feed exclusively at sea. In addition, many species of cormorants, grebes, gulls, jaegers, loons, pelicans and terns feed either entirely or mainly at sea.
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