The young Peregrines wear juvenile plumage for a year, with only slight changes due to wear and fading. Adults moult and replace the wing feathers, one at a time, during the summer. Peregrine Falcon populations were long noted for their stability.
In Great Britain, for example, where a host of birdwatchers and falconers studied Peregrines, the breeding population of some pairs changed little from Elizabethan days the 16th century until the s. During the Second World War, Peregrines were eliminated in some areas to protect homing pigeons. Although these populations recovered after the war, from about onward, many once-vigorous Peregrine populations suffered widespread, unprecedented declines, particularly in Europe and North America.
In the eastern United States, where at least nests were once known, Peregrines were nearly extinct by the s. A decline of such rapidity, magnitude, and distribution at first puzzled ornithologists.
Direct human intervention, such as nest robbing, trapping, or shooting, was ruled out as the primary cause, as Peregrines had been subjected to these onslaughts for hundreds of years. Research studies strongly suggested that persistent chemical pesticides or industrial pollutants were the major cause of the decline. Not only did the Peregrine decline correspond closely in its timing and geographical extent with intensive post-war use of pesticides, but high pesticide residue levels were found in the birds and their eggs.
With few enemies and a long lifespan, Peregrines, like other predators, are at the top of a food chain. Because they ate birds that may have eaten grain or insects treated with pesticides, the Peregrines were exposed to much higher levels of pesticide residues than were found in the air or water.
Pesticide residue levels in their bodies would have been many times higher than the levels in their prey species. At high levels, these chemicals caused reproductive failure by interfering with breeding behaviour, eggshell formation, and hatching success. Thus Peregrine populations gradually dwindled because of the lack of breeding success. Nevertheless, Canadian Peregrines and their prey species probably continued acquiring contaminants on their wintering grounds in Central and South America.
Peregrine Falcons, like virtually all birds of prey, now receive legal protection in most parts of North America. In other parts of the world, however, protection is much less complete, and populations are endangered by adults being shot and young being taken from nests. Since , more than 1 Peregrines have been bred in captivity at the Canadian Wildlife Service breeding facility at Wainwright, Alberta, at university-based facilities in Saskatchewan and Quebec, and at a private facility in Alberta.
In , there were more than pairs of wild Peregrines breeding in southern Canada and more than wild pairs in Yukon and the Mackenzie valley. Over 7 pairs of Peregrines are now thought to breed in North America, including Mexico. Audubon Field Guide, Peregrine Falcon. Government of Ontario, Peregrine Falcon. Print resources Banasch, U. The Peregrine Falcon survey in Canada. Occasional Paper No. Canadian Wildlife Service, Ottawa. Craig, G. Peregrine Falcon biology and management in Colorado — Technical Publication No.
Enderson, J. Heinrich, L. Kiff, and C. Population changes in North American Peregrines. Rowell, P. Holroyd, and U. The Canadian Peregrine Falcon survey. Journal of Raptor Research 37 2 All rights reserved. The Northern Leopard Frog Lithobates pipiens is named for its leopard-like spots across its back and sides. Historically, these frogs were harvested for food frog legs and are still used today for dissection practice in biology class.
Northern Leopard Frogs are about the size of a plum, ranging from 7 to 12 centimetres. They have a variety of unique colour morphs, or genetic colour variations.
They can be different shades of green and brown with rounded black spots across its back and legs and can even appear with no spots at all known as a burnsi morph. They have white bellies and two light coloured dorsal back ridges. Another pale line travels underneath the nostril, eye and tympanum, ending at the shoulder. The tympanum is an external hearing structure just behind and below the eye that looks like a small disk.
Black pupils and golden irises make up their eyes. They are often confused with Pickerel Frogs Lithobates palustris ; whose spots are more squared then rounded and have a yellowish underbelly.
Male frogs are typically smaller than the females. Their average life span is two to four years in the wild, but up to nine years in captivity. Tadpoles are dark brown with tan tails. Lampreys are an amazing group of ancient fish species which first appeared around million years ago. This means they evolved millions of years before the dinosaurs roamed the earth. There are about 39 species of lamprey currently described plus some additional landlocked populations and varieties.
In general, lamprey are one of three different life history types and are a combination of non-parasitic and parasitic species. Non-parasitic lamprey feed on organic material and detritus in the water column. Parasitic lamprey attach to other fish species to feed on their blood and tissues. Most, 22 of the 39 species, are non-parasitic and spend their entire lives in freshwater.
The remainder are either parasitic spending their whole life in freshwater or, parasitic and anadromous. Anadromous parasitic lampreys grow in freshwater before migrating to the sea where they feed parasitically and then migrate back to freshwater to spawn.
The Cowichan Lake lamprey Entosphenus macrostomus is a freshwater parasitic lamprey species. It has a worm or eel-like shape with two distinct dorsal fins and a small tail. It is a slender fish reaching a maximum length of about mm. When they are getting ready to spawn they shrink in length and their dorsal fins overlap. Unlike many other fish species, when lampreys are getting ready to spawn you can tell the difference between males and females.
Females develop fleshy folds on either side of their cloaca and an upturned tail. The males have a downturned tail and no fleshy folds. These seven gill pores are located one after another behind the eye. There are several characteristics which are normally used to identify lamprey.
Many of these are based on morphometrics or measurements, of or between various body parts like width of the eye or, distance between the eye and the snout. Other identifying characteristics include body colour and the number and type of teeth.
Some distinguishing characteristics of this species are the large mouth, called and oral disc and a large eye. This species also has unique dentition.
For example, these teeth are called inner laterals. Each lateral tooth has cusps and together they always occur in a cusp pattern. At the same time, the Sea Otter is the largest member of its family, the mustelids, which includes River Otters, weasels, badgers, wolverines and martens.
It may come to land to flee from predators if needed, but the rest of its time is spent in the ocean. It varies in colour from rust to black. Unlike seals and sea lions, the Sea Otter has little body fat to help it survive in the cold ocean water. Instead, it has both guard hairs and a warm undercoat that trap bubbles of air to help insulate it. The otter is often seen at the surface grooming; in fact, it is pushing air to the roots of its fur.
Mollusks are invertebrates, meaning they have no bones. They are cold-blooded, like all invertebrates, and have blue, copper-based blood. The octopus is soft-bodied, but it has a very small shell made of two plates in its head and a powerful, parrot-like beak. The Giant Pacific Octopus is the largest species of octopus in the world. Specimens have weighed as much as kg and measured 9. Studies determined, though, that they are indeed different. While the Western Chorus Frog might have slightly shorter legs than the Boreal Chorus Frog, and that their respective calls have different structures, genetics have proven this.
Chorus Frogs are about the size of large grape, about 2. They are pear-shaped, with a large body compared to their pointed snout. Their smooth although a bit granular skin varies in colour from green-grey to brownish.
They are two of our smallest frogs, but best ways to tell them apart from other frogs is by the three dark stripes down their backs, which can be broken into blotches, by their white upper lip, and by the dark line that runs through each eye.
Their belly is generally yellow-white to light green. Males are slightly smaller than females, but the surest way to tell sexes apart is by the fact that only males call and can inflate their yellow vocal sacs. Adults tend to live only for one year, but some have lived as many as three years.
Their tadpoles the life stage between the egg and the adult are grey or brown. Their body is round with a clear tail. The Common Raven Corvus corax is one of the heaviest passerine birds and the largest of all the songbirds. It is easily recognizable because of its size between 54 and 67 centimetres long, with a wingspan of to cm, and weighing between 0. It has a ruff of feathers on the throat, which are called 'hackles', and a wide, robust bill. 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.
In general, the Lanner Falcon is doing well but the European population is experiencing a decline and is at risk.
Like most other falcons, the Lanner Falcon feeds mostly on birds — small and large — including larks, ducks, sandgrouse, poultry, doves, and even other small raptors. One biologist observed a Lanner Falcon attacking a bustard, a bird about two to three times heavier than the falcon!! But the Lanner Falcon doesn't eat only birds. It eats a whole host of other animals including small mammals, such as bats and rodents such as the common gundi, the fat sand rat yes, that is really its name , and the Eastern rock elephant shrew.
This falcon also feeds on snakes, lizards, and insects such as termites, locusts and grasshoppers. Such a diet requires a variety of hunting techniques.
The Lanner Falcon may capture prey after fast pursuits or it may fly up above its quarry and make a hard stoop onto it. This species is also known to hunt by flying low over the ground or along slopes and cliffs as it searches for prey.
This falcon can often be seen hunting in pairs, often with one bird flushing the prey and the other making the grab. Scientists have even documented these falcons following people as they walk in certain habitats to catch any prey the humans may scare up. Instead, it lays its eggs in small scrapes on rock ledges of high cliffs or in abandoned nests of other species, including storks, crows, and other raptors, both in trees and on power poles.
In open desert, they may nest directly on the ground among rocks. During courtship, the male and female engage in some impressive flight displays. When the time comes, the female lays eggs, sometimes five.
Both the male and the female work together to care for and protect their eggs and young. First, they must spend around 32 days ncubating the eggs, and then another 42 days protecting and feeding their chicks.
When the young fledge, or fly for the first time, parent care doesn't stop. The young remain with their parents for up to another three months, while they learn to hunt, avoid predators, and otherwise take care of themselves. When Lanner Falcons are two to three years old, they are old enough to find a mate and begin raising young of their own.
The most common factor among these different locations is the presence of good nesting habitat. These falcons like to nest in high cliffs, but in cities, Peregrine Falcons use tall buildings or bridges instead. As in many urban settings, a resident falcon family returns from migration each spring to raise young on the ledge of a tall building in downtown Boise, Idaho.
Among the most impressive birds to watch hunt, Peregrine Falcons are known for their high speeds, impressive aerial acrobatics, and unmistakable grace. But Peregrine Falcons not only fly fast, some populations fly incredibly long distances, too. In the northern part of their range, Peregrine Falcons are migratory, which means they travel from their breeding grounds to non-breeding grounds and back every year.
Some of these individuals travel from the Arctic nearly to Antarctica, making a yearly round trip journey of more than 20, miles.
That would be like crossing the entire United States seven times in one year! Peregrine Falcons that live closer to the equator tend not to migrate.
This makes sense if you think about one definition of migration: the seasonal movement from one area to another for the purpose of finding food or to reproduce, usually triggered by a change in the weather. Since temperatures along the equator are not as extreme as in the northern and southern regions of the world, there tends to be more year-round prey. With more available prey, there is no reason for a Peregrine Falcon to leave its home.
Even when they are raising young, the tropical regions of the world usually provide them with enough food to raise a healthy family. Perhaps because of their amazing flying and hunting skills, Peregrine Falcons have had cultural significance for humans throughout history. To this day, they are still one of the most popular birds in the sport of falconry, and in ancient times they were considered the birds of royalty.
Today, Peregrine Falcons that are trained as falconry birds are sometimes flown by their trainers at airports to scare off ducks and other birds that could collide with a plane and cause accidents. These falcons are helping to keep our skies safe! The Peregrine Falcon also appears on the U.
Idaho state quarter. In the s, when Peregrine Falcons began to disappear, scientists wanted to understand why. This led them to discover the environmental dangers of DDT, not just for birds but for other wildlife and humans as well. By studying Peregrine Falcons, we continue to learn more about long-term effects from other environmental contaminants. Part of this work takes them to South Padre Island, Texas, to measure the effects of the large oil spill that occurred in the Gulf of Mexico in There they capture falcons using specially designed traps and bait.
By comparing these blood samples with samples collected before the oil spill, biologists will be able to detect changes in amounts and composition of pollutants. Because Peregrine Falcons are part of a fragile, complicated food web, scientists will be able to tell whether the oil spill is having long-term effects on a variety of wildlife. Learning about how these issues affect Peregrine Falcons can tell us how wildlife and humans may be affected as well.
As in the case of DDT, this information can help stop the use of dangerous contaminants — good news for all of us. Peregrine Falcons are mainly bird hunters; starlings, pigeons, blackbirds, jays, shorebirds, and waterfowl are all fair game for a hungry Peregrine Falcon. They also occasionally hunt mammals, reptiles, and insects and there have even been reports of some Peregrine Falcons specializing in eating bats.
A hunting Peregrine Falcon uses many strategies for catching a good meal but they typically catch their prey in the air with fast pursuits, rapid dives, and other impressive aerial maneuvers for which these falcons are known and admired. Perhaps its most famous hunting technique is the dive. To pull this off, a Peregrine Falcon flies high into the sky, using its keen eyesight to locate birds flying below.
When it finds its target, the falcon folds its wings and falls into a nose dive, or stoop, gaining speeds over mph. The falcon closes its feet, and uses them to knock the prey out of the sky. When not stooping after its prey, Peregrine Falcons go after their quarry in a swift aerial chase, flapping their wings furiously in hot pursuit of a meal. Though it cannot move as fast as when in a nose dive, a Peregrine Falcon, in horizontal flight, can still rival a cheetah for speed!
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