RSS
 

Author Archive

Panther

25 Apr

A black panther is a large black cat. Black panthers are melanistic colour variants of several species of larger cat. Wild black panthers in Latin America are black jaguars (Panthera onca), in Asia and Africa black leopards (Panthera pardus), and in North America may be black jaguars or possibly black cougars (Puma concolor – although this has not been proven to have a black variant), or smaller cats.

Black panthers are also reported as cryptids in areas such as the United States, the United Kingdom and Australia, and for these (if they do exist) the species is not known. Captive black panthers may be black jaguars, or more commonly black leopards. Black panthers have sometimes been regarded as forming different species from their normally-colored relatives.

The name “panther” is often limited to the black variants of the species, but is also used to refer to those which are normally-colored for the species (tawny or spotted), or to white color variants: white panthers.

Black Panther

Black Panther

 

Vulture

25 Apr

What is the Difference between New World and Old World Vultures?

Vultures are all large, carrion-eating birds.  For years, it was believed that all vultures were raptors, members of the order Falconiformes.  In 1994, however, it was discovered that the vultures inhabiting the American continents share a common ancestor with storks and ibises.  Now, American vultures, or New World vultures, are recognized as Ciconiiformes, in the family Cathartidae.  European, African, and Asian vultures are recognized as Old World vultures (family Accipitridae, subfamily Aegypiinae).  There are 15 species of Old World Vultures and 7 Species of New World Vultures.

Turkey Vulture

Turkey Vulture


General Information

I’m sure you’ve gazed at one of those noble, graceful figures soaring in the sky on a mild day… Well, what you are seeing is probably not a hawk.  It is a vulture.  Vultures are one of very few creatures capable of soaring for hours at a time.  And it is effortless.  For years, superstitious individuals have claimed that the sight of soaring vultures is a sure signal that a dead animal can be found nearby.  This is not true.  Vultures are highly intelligent creatures who love to play as much as humans.  When a vulture discovers a thermal (warm pocket of air), the bird is able to hold its wings motionless, and allow the warm air to carry it in large, sweeping circles, toward the sky.

Ugly Animal?

The vulture’s bald head is one feature that appears revolting to many people, but it is a brilliant physiological property that allows the creature to plunge into all sorts of carcasses, and come out clean.  Without feathers to serve as a habitat for all the bacteria that infests their meals, vultures soar through their lives disease-free.  After eating, vultures can often be seen perched in the heat of the sun.  Here, whatever has managed to cling to the few bits of fuzz on their head will be baked off once and for all.
Many of the behavioral traits of the vulture have brought it considerable (and unfair) attention as an unsanitary creature.  However, each habit of the vulture is an adaptation, evolved to help it survive under the conditions in which it lives.  First of all, a diet of dead and decaying flesh would turn our stomachs inside out.  But think of how our landscape would look without the help of the vulture.  Serving as nature’s janitors, these wonderful birds fly about, stomaching the most revolting of cuisine, and ridding our ecosystem of maggots and disease-carrying viruses in the process.  With 100 times the botulism of a human, the stomach of a vulture can digest meat in advanced stages of decay, a favor to every other creature in the world.
 
No Comments

Posted in Vultures

 

Hawk | Kites

25 Apr

Kites are raptors with long wings and weak legs which spend a great deal of time soaring. Most feed mostly on carrion but some take various amounts of live prey.

They are birds of prey which, along with hawks and eagles, are from the family Accipitridae.

Red Kites

Red Kites are distinctive because of their forked tail and striking colour – predominantly chestnut red with white patches under the wings and a pale grey head.
They have a wingspan of nearly two metres (about five-and-a-half-feet), but a relatively small body weight of 2 – 3 Ibs.
This means the bird is incredibly agile, and can stay in the air for many hours with hardly a beat of its wings.

Red Kite

Red Kite

Red Kites are neither particularly strong nor aggressive despite being large birds.
Primarily a scavenger and an opportunist; it profits from sheep carrion but is not capable of opening up sheep or lamb carcasses by itself and has to wait until more powerful birds such as ravens or buzzards have made the first inroads before it will attempt to feed.
Red Kites are however predators and take a wide variety of live prey, ranging from earthworms to small mammals, amphibians and birds.

Red Kites usually breed for the first time at 2 or 3 years old. They usually pair for life, although this is thought to be more because of a mutual attachment to the same territory and nest sites rather than any great attachment to each other.

There are a few recorded cases of ‘divorces’ where both members of the original pair were later found breeding with different partners.
Nests are built almost exclusively in trees – mostly in hardwoods, such as oaks, and are usually built at a height of between 4 and 30 metres above the ground. They are usually fairly flat, untidy structures of sticks about 2 feet in width.

For established pairs, courtship and nest-building usually start in earnest during March, about 2 – 4 weeks before the first egg is laid, but first-time breeders may not start until April.

Eggs are normally laid at three-day intervals. Between one and four are usually laid, two being by far the most usual number. Incubation is carried out by the female, who is fed at the nest by the male. Males will incubate for very short periods (usually less than 30 minutes) while the female goes off to feed, hunt or preen. Each egg will hatch between 31 and 35 days after incubation, resulting in chicks hatching at two or three day intervals.

Because of this, sibling aggression is common and the larger chick will peck vigorously at its younger nest-mates if they attempt to get food before it has had its fill. In nests where food is in short supply the size difference between the chicks will increase with the smaller one(s) ultimately dying of starvation or being killed by the larger chick(s).

 
 

Hawk | Falcon

25 Apr

The falcons of the world are fascinating to many people, both birders and non-birders. They can be found almost anywhere on earth (except Antarctica) and some species coexist well with humans. The sport of falconry (using falcons to hunt gamebirds) goes back many centuries. I suppose the fascination for many is the combination of speed and elegant lines in a lethal predator.

I never quite caught this special fascination with falcons although I think they are very impressive and beautiful to observe (but I can say the same for many other types of birds). Perhaps my “most memorable” falcon is the bird at left, a spectacular Lanner Falcon at the tip of the Sinai Peninsula in November 1981 (the Sinai was then Israeli occupied; it is now part of Egypt). It is particularly memorable because although I took this photo, I have no memory of it. A week before I had tumbled from a second-floor balcony and been knocked unconscious; I was apparently air-lifted to a hospital by the army. There is an entire blank week in my memory here, but I took extensively field notes of my birding during the days after I returned. I also took rolls of film. One roll starts with a close-up of a Bar-tailed Godwit, then the next shot is a blur of brown feathers hitting to godwit, and then a series of the falcon carrying it off to be devoured. Some of my best stuff — and my only recollections are these photos. Its a weird feeling.

While the big falcons are glamorous and get all the ink, I am more emotional about the story of the Mauritius Kestrel (right). Over the sorry history of man’s destruction of birds and their habitats, this is one of the best success stories going. When I first began birding at a more active pace and my thoughts first turned to world birding in 1974, this was considered the rarest bird in the world. There were only two nesting pairs but two unmated individuals — a total of just six birds — left in the world. But conservationists, spearheaded by Tom Cade, Stanley Temple, C. G. Jones and others, got international backing just in time. They developed a captive breeding program and a public awareness campaign. By the publication of Cade’s (1982) Falcons of the World there were 15 in the wild; 1983 ten of those were captured for breeding (see Jones 1980 for more details). The government of Mauritius also increased the sizes of reserves. When I visited ten years later (1992) the program was going so well there were 250 in the wild and many still being raised in captivity. I understand the wild population is now up to 500 or so and all available habitats on the island have been recolonized. Given this dramatic history — an escape from extinction that passed through a genetic bottleneck when numbers were so low — I still consider the Mauritius Kestrel of the “best birds in the world,” even though today’s birder need only visit Mauritius briefly to see one.

Among the falcons, some 13 species are called “kestrels” but all of these are still retained in the genus Falco that includes all the large hunting falcons; together the genus Falco comprises 38 species, or 60% of the Falconidae.

The other species within the Falconidae are scattered among the caracaras — long-legged neotropical birds, some of which include carrion in their diet, the unique Laughing Falcon Herpetotheres cachinnans and the forest-falcons of the Neotropics (many of them secretive), and the pygmy-falcons and falconets of the Old World tropics. The latter are tiny species like this Pygmy Falcon (below; photo by Dale & Marion Zimmerman) of the open plains of East Africa. The small falconets hunt the forests of Southeast Asia, Borneo and the Philippines.

In the New World, the caracaras can be conspicuous. Birds in the “Crested Caracara” group are prime examples. They are very much an open country bird and readily willing to take carrion. This Southern Caracara (above left) on the Brazilian Pantanal has just recently been split from the Northern Caracara Caracara plancus which ranges from south Texas and Florida to northern South America (Dove & Banks 1999). Their ranges are divided by the Amazon River, and the southern species has a uniformly barred back, rump and tail (and breast) unlike the white-chested, black-backed birds north of the river. Other caracaras are forest edge species, often following the rivers through the lowlands and hunting along the banks. The Black Caracara (below) is such a bird. It is widespread in the South American lowlands; here it uses driftwood on a Napo River islet as a hunting post.



The best known falcon is the Peregrine (above in a fine photo by Ed Greaves) which, if I’m not mistaken, has the most extensive range of any bird species in the world. It is a magnificent hunter, dropping from the skies at high speeds on its prey. This photographed Peregrine has just taken, plucked, and eaten a shorebird on a beach in northern California but Peregrines also prey heavily on waterfowl and, in cities around North America, the prey is mostly introduced Rock Doves (feral pigeons). There the Peregrine has adapted to city life by nesting on skyscraper ledges or bridge girders which replicate the conditions of the steep, inaccessible cliffs it uses for breeding in the wilderness.

In the United States, Peregrines were once more widespread and reasonably common but the species suffered precipitous continental declines in the 1960s and early 1970s due to pesticides, shooting, and nest-robbing for falconry. The widespread use of the pesticide DDT caused eggshell thinning; thin eggs easily broke and eventually nest sites were abandoned. By the early 1970s only one pair was known to nest in the California. In my home county (Monterey) Peregrines had historically been known at some 24 nest sites but the last site was abandoned in the mid-1960s. Fortunately the banning of DDT and governmental listing as an Endangered species, aided tremendously by a hands-on recovery program, have returned the Peregrine to a stable healthy population. The recovery effort was spearheaded in the late 1970s and 1980s by the Santa Cruz Predatory Bird Research Group who removed thin-shelled eggs from nests for safe hatching in captivity, returned young to nests and then closely monitored their success. The Ventana Wilderness Society also released captive-reared birds from a hack site above the Big Sur coast beginning in 1986. By 1980 there were again five Monterey County nests occupied that fledged 4 young. The active intervention phase of Peregrine Falcon management ended in my county about 1990. With these management efforts the local breeding population has rebounded; today there are 6-9 nests from Hurricane Pt. south to the San Luis Obispo Co. line, and it is possible that traditional interior sites have been or will be reclaimed.

 
 

Hawk | Eagle

25 Apr

The world’s 59 species of eagles are found on every continent except Antarctica. There are four major groups of eagles: fish eagles, booted eagles, snake eagles and giant forest eagles. America’s eagles are the Bald Eagle, which is a fish eagle, and the Golden Eagle, which is a booted eagle. Golden and Bald Eagles both reside in the United States.

The Bald Eagle (Haliaeetus Leucocephalus) is the only eagle species living strictly in North America. It is a fish eagle that has a presence in every state in the U.S.A. except Hawaii. The Bald Eagle can have a wing span of up to eight feet and can weigh up to 15 pounds. It inhabits areas near large bodies of water where there are plenty of fish to eat and tall trees in which to nest and roost. Bald Eagles are monogamous and remain faithful to their mate until death. Females lay one to three eggs annually in the spring time, and the incubation period is approximately 35 days.

American Blad Eagle

American Blad Eagle

Young (immature) Bald Eagles are dark brown in color when they fledge the nest at about 12 weeks of age, and the head and tail feathers turn predominantly white in their fourth or fifth year. Bald Eagles can live up to 40 years in the wild and longer in captivity. They are primarily fish eaters. Other fish eagles that can be found outside the United States around the world include: White-bellied Sea Eagle (White-breasted Sea Eagle), Solomon Sea Eagle (Sanford’s Sea Eagle), African Fish Eagle, Madagascar Fish Eagle, Pallas’ Fish Eagle (Band-tailed Fish Eagle), White-tailed (Sea) Eagle (Gray Sea Eagle), Lesser Fishing Eagle, Greater Fishing Eagle (Gray headed Fishing Eagle) and Steller’s Sea Eagle.

Immature Bald Eagle

Immature Bald Eagle

The Golden Eagle (Aquila Chrysaetos) is a large brown and golden colored booted eagle that can be found in mountainous areas of the U.S.A. This bird of prey can weigh up to 15 pounds and can have a wing span of up to eight feet. It ranges throughout the Western Hemisphere, Europe and Asia. It builds nests on mountain rocks and ledges, and feeds on small mammals and reptiles.

Other booted eagles that can be found outside the U.S. around the world include: Asian Black Eagle, Lesser Spotted Eagle, Greater Spotted Eagle, Tawny Eagle, Steppe Eagle, Imperial Eagle, Gurney’s Eagle, Wedge-tailed Eagle, Verreaux’s Eagle (African Black Eagle), Wahlberg’s Eagle, Bonelli’s Eagle, African Hawk Eagle, Booted Eagle, Little Eagle, Ayre’s Hawk Eagle, Rufous-bellied Eagle, Martial Eagle, Black & White Hawk Eagle, Long-crested Eagle, Cassin’s Hawk Eagle, Crested Hawk Eagle (Changeable Hawk Eagle), Mountain Hawk Eagle, Java Hawk Eagle, Celebes Hawk Eagle, Phillipine Hawk Eagle, Blyth’s Hawk Eagle, Wallace’s Hawk Eagle, African Crowned Eagle, Ornate Hawk Eagle, Black Hawk Eagle (Tyrant Hawk Eagle), and Black

Golden Eagle

Golden Eagle

The Harpy Eagle (Harpia harpyja) is a splendid example of a Giant Forest Eagle. It is a lovely grey, black and white bird with a prominent crest. It is endowed with thick legs and massive feet. It is perhaps the largest eagle in the world, with some females weighing 20 lbs. or more. It lives in the rainforests of Central and South America, and preys primarily on birds and various mammals, including sloths and monkeys. It builds a huge stick nest in the crotch of an emergent forest tree. It is currently a threatened species due to the destruction of the rainforests. Other Giant Forest Eagles that can be found around the world include: the highly endangered Philippine Eagle, the Guiana Crested Eagle, and the New Guinea Eagle.

Harpy eagle

Harpy eagle

The Bateleur Eagle (Terathopius ecaudatus) is an abberrent, but well known member of the Serpent or Snake Eagle group. Like other members of the group, the Bateleur Eagle has a large head covered with long feathers and stocky legs with short stubby toes – ideal for grasping snakes. Unlike some Snake Eagles, the Bateleur, which is “acrobat” in French, spends a lot of time soaring. It may cover 100 miles or more a day in search of food, which includes carrion and animals such as antelope, mice, birds and various reptiles. The Bateleur is a large, handsome jet black eagle with white under the wings, rufous tail and back, gray on the shoulders, bright crimson face and legs, and a black beak. Females are around 24 inches in length, and males are slightly smaller. Wingspans range from 6 to 7 feet. The Bateleur is found in the tree and brush savanna throughout Africa, south of the Sahara. Other Snake Eagles that can be found around the world include: Short-toed Eagle, Brown Snake Eagle, East African Snake Eagle (Southern Banded Snake Eagle), Banded Snake Eagle, Crested Serpent Eagle, Kinabalu Serpent Eagle, Nicobar Serpent Eagle, Andaman Serpent Eagle, Congo Serpent Eagle (African Serpent Eagle) and Madagascar Serpent Eagle.

Bateleur Eagle

Bateleur Eagle

 
 

Hawk – Buteos

25 Apr
Buteos have broad wings with deeply slit wing tips that are used for extensive
soaring flight. These hawks have short, stout legs with short toes. Buteos
are found nearly worldwide in open country and some forested areas.
large

Broad-winged hawk (Buteo platypterus)

The Broad-winged Hawk is one of the smallest buteos, about the size of a crow. It is 14 to 19 inches long, with a wingspan of about 3 feet. Its relatively short wings and tail give the bird a chunky appearance in flight.

The adult is grayish-brown on the back, and its underparts are white, heavily barred with reddish-brown. Its tail is dark, with two or three equally wide white bands. The immature is brown-backed, and its underparts are whitish with vertical brown streaks. The barring in the tail of the young bird is not as prominent as in the adult. Broad-winged Hawks breed throughout eastern North America, from Canada to Florida. Many nest in New Jersey in areas where proper habitat still exists, primarily deep deciduous forests. In early autumn they begin a spectacular migration southward, some going as far as South America. During this time huge concentrations of these hawks can be seen along the mountain and coastal flyways of our state.

Their diet consists of a wide variety of prey animals including small mammals, snakes, frogs and toads, grasshoppers and caterpillars.

Red-shouldered hawk (Buteo lineatus)

Red-shouldered Hawks are medium-sized slender buteos, larger than Broad-wings but smaller than Red-tails. They have body lengths of 18 to 24 inches and wingspans of 3!/2 to 4 feet. Their backs are brown, flecked with white, and their shoulders are rufous. Immature birds have brown teardrop-shaped streaks on their white breasts; adults have pale robin-red underparts.

Red-shouldered Hawks inhabit low, wet, open woodlands usually near a river, stream or swamp. They prey upon the wide variety of animal life found there: small mammals, frogs, snakes, lizards, insects and birds.

Some Red-shoulders remain resident in New Jersey year round, but most migrate southward as winter approaches. They were once common here, but loss of their preferred habitat and other factors not yet clearly identified have reduced their numbers. At present their breeding population is considered endangered in the state.

Red-tailed hawk (Buteo jamaicensis)

New Jersey’s most common large hawk, the Red-tail, is named for the rufous color of the adult’s tail. These buteos are often seen soaring in wide circles or perched conspicuously in trees along roadsides. Vocal hawks, their distinctive call – a high, shrill “kree-e-e” – is usually uttered in flight.

Red-tails stand about 2 feet tall and have wingspans of 4l/2 to 5 feet. They are dark brown above, white to cinnamon below, and usually have a band of dark streaks across the belly. Immature birds are similar to adults in plumage except for their tails – the young have brown tails for their first year. When they molt, these brown feathers are replaced by the characteristic red of the species.

Red-tailed Hawks are found throughout North America and many live in New Jersey year round. They prefer a habitat of fields and pastures mixed with open woodlands. Their large stick nests are usually built in the tallest available tree. From one to three young are raised each year.

Their diet consists mainly of mammals and includes mice, voles, squirrels and rabbits.

Rough-legged hawk (Buteo lagopus)

The Rough-legged Hawk breeds in the far north and occurs in New Jersey only as a rare winter visitor. Like many northern species, it is protected from the cold by feathers that cover even its legs and toes. Its common and scientific names both refer to the furry appearance of its legs; the Greek word lagopus means “hare-footed.”

Rough-legged Hawks are large, about 2 feet long with wingspans of 4l/2 feet. Plumage color varies greatly in this species from light to very dark (melanistic) individuals. All have a conspicuous white rump patch and a wide, dark band at the tip of the tail.

Birds of open country and graceful soarers, Rough-legs can be distinguished from other buteos in flight by their longer wings and tails. They have a habit of hovering in one spot, as Kestrels and Ospreys do.

Rough-legged Hawks are rodent eaters and feed on small animals, primarily meadow voles.

 
 

Hawk | Accipiters

25 Apr

The northern goshawk (Accipiter gentilis) and the sharp-shinned hawk (Accipiter striatus) are the Alaskan representatives of a group of hawks known as accipiters, with short, rounded wings (short in comparison with other hawks) and long tails. The third North American accipiter, the Cooper’s hawk (Accipiter cooperii) is not found in Alaska. Both native species are abundant in the state but not commonly seen, for they spend the majority of their time in wooded habitats. When they do venture out into the open, the accipiters can be recognized easily by their “several flaps and a glide” style of flight.

sshawk

General Description: Adult northern goshawks are bluish- gray on the back, wings, and tail, and pearly gray on the breast and underparts. The dark gray cap is accented by a light gray stripe above the red eye. Like most birds of prey, female goshawks are larger than males. A typical female is 25 inches (65 cm) long, has a wingspread of 45 inches (115 cm) and weighs 2¼ pounds (1020 g) while the average male is 19½ inches (50 cm) in length with a wingspread of 39 inches (100 cm) and weighs 2 pounds (880 g).

Adult sharp-shinned hawks have gray backs, wings and tails (males tend to be bluish-gray, while females are browner) with white underparts barred heavily with brownish-orange. They also have red eyes but, unlike goshawks, have no eyestrip. A typical female weighs 6 ounces (170 g), is 13½ inches (35 cm) long with a wingspread of 25 inches (65 cm), while the average male weighs 3½ ounces (100 g), is 10 inches (25 cm) long and has a wingspread of 21 inches (55 cm).

In both species, immature birds are brown on the back, wings and tail, with buff-colored underparts streaked with brown. The eyes of young accipiters are yellow; it takes several years for them to change to the red of adults. Young goshawks have a buff eyestripe. In both species, the long tail is broadly banded with dark gray in adults and dark brown in immatures. The tail is tipped with white in adults and buff in immatures.

Food Habits: Accipiters are adept at flying quickly through dense woods in search of their favored prey. The hawks’ short, broad wings enable them to accelerate rapidly, and their long tails are efficient rudders for steering around trees. The birds employ this ability to negotiate wooded habitats in hunting. They perch quietly in trees or move stealthily from perch to perch. When prey is sighted, they make a rapid dash after it. If the intended prey is not caught quickly, the pursuit is dropped after a short distance. When the hawks do get close, they reach out with their long legs and grab the animal with powerful, taloned feet. Goshawks have tremendously strong feet and legs and are capable of subduing large prey, such as snowshoe hares, grouse, ptarmigan, and ducks. They also eat squirrels, voles, shrews, and some of the larger songbirds and shorebirds. In contrast, the more maneuverable sharpshinned hawks have proportionally longer, narrower toes and are more efficient at capturing songbirds. Sharp-shins also eat a few small mammals and occasionally catch large insects. Typically, a few feathers or tufts of fur are ingested with each meal. These, along with bones and fragments of insect exoskeleton, are not digested but are bundled into compact “pellets” and regurgitated. Pellets can often be found among prey remains near the birds’ favorite perches (accipiters usually take their kills to “plucking perches” or “butcher blocks” where they pull out the feathers or fur of prey before eating it). Pellets and other remains provide biologists with valuable clues to the hawks’ diets.

Life History: While accipiters can and do exploit a variety of habitats for hunting, they prefer to nest in mixed stands of coniferous and deciduous trees. They often return to the same general area in successive years and will occasionally reuse an old nest. The area immediately surrounding the nest is vigorously defended against intruders—the adults scream and dive at interlopers, slashing and grabbing at the offenders with their feet.

Northern goshawks build large stick nests, usually in a major crotch of birch or aspen trees. Nesting usually begins in early to mid-April, often when there is still snow on the ground. Goshawks lay one to four eggs, with three or four being the most common clutch sizes. Young goshawks hatch in late May or early June, grow quickly, and fledge in early to mid-July. The young birds remain in the vicinity of the nest as they develop their powers of flight and sharpen their hunting skills. The parents continue to feed their offspring for as long as the young birds remain in the area, often until early August. Northern goshawks do not make long-distance migrations and can be found year-round throughout their range in Alaska.

Sharp-shinned hawks nest most frequently in middle-age (25-45 years old) spruce trees. They usually build their bulky twig nests close to the trunk midway up the nest tree. Sharp-shins lay three to six eggs (most commonly five or six) in late April or early May, and the young hatch about 35 days later. Young sharp-shins grow rapidly and fledge 22 to 25 days after hatching—about the same time that young goshawks are leaving the nest.

Sharp-shins follow the same post-fledging pattern as goshawks, but their dispersal from the nest area is faster. Most sharp-shins follow waves of migrating songbirds in the fall and spend the winter in the warmer regions, although some individuals overwinter in Southcentral and Southeast Alaska.

Because young accipiters usually weigh less than their parents and have slightly longer flight feathers, their wing loading is lower (i.e., less weight distributed over a large wing area). This enables young birds to fly slower and more buoyantly than adults, but they still occasionally fall victim to their own clumsiness and fatally miscalculate a landing. A large number of birds succumb to other hazards, including disease, predation, flying into windows, being shot by humans, and being struck by vehicles. The first hard freeze of the year eliminates many birds, especially those sharp-shinned hawks which have not yet gone south. Goshawks also fall victim to the weather; birds which are barely able to catch enough food to stay alive in warm weather don’t survive for long when cold weather increases the food intake requirements. As many as 80-90 percent of birds die during their first winter.

Northern goshawks have few enemies in the wild other than the elements. They are rarely caught in a position where they are unable to either defend themselves or evade their attacker. They are most vulnerable when the female is incubating eggs or brooding small nestlings and when the young are first learning to fly. At these times, other large hawks or owls occasionally kill goshawks; and bears, lynx, and other climbing predators sometimes reach nests and eat young birds. Sharp-shinned hawks have similar enemies, including the goshawk itself. Although many goshawks are killed in the name of defense of poultry or other small livestock, only a few birds actually deserve the oft-applied title, “chicken hawk.”

While it is illegal to kill raptors, the goshawk and the sharp-shinned hawk may be kept in captivity by falconers, providing they have the required permit, which is issued jointly by state and federal authorities.

Preservation of Alaska’s raptors depends on research and habitat protection. Increased knowledge and preservation of critical habitat will help perpetuate the woodland hawks of Alaska.

 

Cheetah

23 Apr

The cheetah (Acinonyx jubatus) is an atypical member of the cat family (Felidae) that is unique in its speed, while lacking climbing abilities. The species is the only living member of the genus Acinonyx. It is the fastest land animal, reaching speeds between 112 and 120 km/h (70 and 75 mph) in short bursts covering distances up to 460 m (1,510 ft), and has the ability to accelerate from 0 to 103 km/h (64 mph) in three seconds, faster than most supercars. Recent studies confirm the cheetah’s status as the fastest land animal.

Cheetah

Cheetah

Genetics and classification

The genus name, Acinonyx, means “no-move-claw” in Greek, while the species name, jubatus, means “maned” in Latin, a reference to the mane found in cheetah cubs.

Mother with cub.

The cheetah has unusually low genetic variability and a very low sperm count, which also suffers from low motility and deformed flagella.[8] Skin grafts between non-related cheetahs illustrate this point in that there is no rejection of the donor skin. It is thought that it went through a prolonged period of inbreeding following a genetic bottleneck during the last ice age. It probably evolved in Africa during the Miocene epoch (26 million to 7.5 million years ago), before migrating to Asia. New research by a team led by Warren Johnson and Stephen O’Brien of the Laboratory of Genomic Diversity (National Cancer Institute in Frederick, Maryland, United States) has recently placed the last common ancestor of all existing species as living in Asia 11 million years ago, which may lead to revision and refinement of existing ideas about cheetah evolution. Now-extinct species include: Acinonyx pardinensis (Pliocene epoch), much larger than the modern cheetah and found in Europe, India, and China; Acinonyx intermedius (mid-Pleistocene period), found over the same range. The extinct genus Miracinonyx was extremely cheetah-like, but recent DNA analysis has shown that Miracinonyx inexpectatus, Miracinonyx studeri, and Miracinonyx trumani (early to late Pleistocene epoch), found in North America and called the “North American cheetah” are not true cheetahs, instead being close relatives to the cougar.

Subspecies

Although many sources list six or more subspecies of cheetah, the taxonomic status of most of these subspecies is unresolved. Acinonyx rex—the king cheetah (see below)—was abandoned after it was discovered the variation was only a recessive gene. The subspecies Acinonyx jubatus guttatus, the woolly cheetah, may also have been a variation due to a recessive gene. Some of the most commonly recognized subspecies include:[9]

  • Asiatic Cheetah (Acinonyx jubatus venaticus): Asia (Afghanistan, India, Iran, Iraq, Israel, Jordan, Oman, Pakistan, Saudi Arabia, Syria, Russia)
  • Northwest African Cheetah (Acinonyx jubatus hecki): Northwest Africa (Algeria, Djibouti, Egypt, Mali, Mauritania, Morocco, Niger, Tunisia and Western Sahara) and western Africa (Benin, Burkina Faso, Ghana, Mali, Mauritania, Niger, and Senegal)
  • Acinonyx jubatus raineyii: eastern Africa (Kenya, Somalia, Tanzania, and Uganda)
  • Acinonyx jubatus jubatus: southern Africa (Angola, Botswana, Democratic Republic of the Congo, Mozambique, Malawi, South Africa, Tanzania, Zambia, Zimbabwe and Namibia)
  • Acinonyx jubatus soemmeringii: central Africa (Cameroon, Chad, Central African Republic, Ethiopia, Nigeria, Niger, and Sudan)
  • Acinonyx jubatus velox

Description

The cheetah’s chest is deep and its waist is narrow. The coarse, short fur of the cheetah is tan with round black spots measuring from 2 to 3 cm (0.79 to 1.2 in) across, affording it some camouflage while hunting. There are no spots on its white underside, but the tail has spots, which merge to form four to six dark rings at the end. The tail usually ends in a bushy white tuft. The cheetah has a small head with high-set eyes. Black “tear marks” run from the corner of its eyes down the sides of the nose to its mouth to keep sunlight out of its eyes and to aid in hunting and seeing long distances. Although it can reach high speeds, its body cannot stand long distance running. It is a sprinter.

The adult cheetah weighs from 36 to 65 kg (79 to 140 lb). Its total body length is from 115 to 135 cm (45 to 53 in), while the tail can measure up to 84 cm (33 in) in length. Cheetah are 67 to 94 cm (26 to 37 in) in high at the shoulder. Males tend to be slightly larger than females and have slightly bigger heads, but there is not a great variation in cheetah sizes and it is difficult to tell males and females apart by appearance alone. Compared to a similarly-sized leopard, the cheetah is generally shorter-bodied, but is longer tailed and taller (it averages about 90 cm (35 in) tall) and so it appears more streamlined.

Some cheetahs also have a rare fur pattern mutation: cheetahs with larger, blotchy, merged spots are known as “king cheetahs”. It was once thought to be a separate subspecies, but it is merely a mutation of the African cheetah. The “king cheetah” has only been seen in the wild a handful of times, but it has been bred in captivity.

A cheetah.

The cheetah’s paws have semi-retractable claws (known only in three other cat species: the Fishing Cat, the Flat-headed Cat and the Iriomote Cat) offering extra grip in its high-speed pursuits. The ligament structure of the cheetah’s claws is the same as those of other cats; it simply lacks the sheath of skin and fur present in other varieties, and therefore the claws are always visible, with the exception of the dewclaw. The dewclaw itself is much shorter and straighter than that of other cats.

Adaptations that enable the cheetah to run as fast as it does include large nostrils that allow for increased oxygen intake, and an enlarged heart and lungs that work together to circulate oxygen efficiently. During a typical chase its respiratory rate increases from 60 to 150 breaths per minute. While running, in addition to having good traction due to its semi-retractable claws, the cheetah uses its tail as a rudder-like means of steering[citation needed] to allow it to make sharp turns, necessary to outflank prey animals that often make such turns to escape.

Unlike “true” big cats, the cheetah can purr as it inhales, but cannot roar. By contrast, the big cats can roar but cannot purr, except while exhaling. However, the cheetah is still considered by some to be the smallest of the big cats. While it is often mistaken for the leopard, the cheetah does have distinguishing features, such as the aforementioned long “tear-streak” lines that run from the corners of its eyes to its mouth. The body frame of the cheetah is also very different from that of the leopard, most notably so in its thinner and longer tail and, unlike the leopard’s, its spots are not arranged into rosettes.

The cheetah is a vulnerable species. Out of all the big cats, it is the least able to adapt to new environments. It has always proved difficult to breed in captivity, although recently a few zoos have managed to succeed at this. Once widely hunted for its fur, the cheetah now suffers more from the loss of both habitat and prey.

The cheetah was formerly considered to be particularly primitive among the cats and to have evolved approximately 18 million years ago. New research, however, suggests that the last common ancestor of all 40 existing species of felines lived more recently than that—about 11 million years ago. The same research indicates that the cheetah, while highly derived morphologically, is not of particularly ancient lineage, having separated from its closest living relatives (Puma concolor, the cougar, and Puma yaguarondi, the jaguarundi) around five million years ago. These felids have not changed appreciably since they first appeared in the fossil record.

Morphs and variations

King cheetah

A king cheetah showing its unique coat pattern.

The king cheetah is a rare mutation of cheetah characterized by a distinct pelt pattern. It was first noted in Zimbabwe in 1926. In 1927, the naturalist Reginald Innes Pocock declared it a separate species, but reversed this decision in 1939 due to lack of evidence, but in 1928, a skin purchased by Walter Rothschild was found to be intermediate in pattern between the king cheetah and spotted cheetah and Abel Chapman considered it to be a color form of the spotted cheetah. Twenty-two such skins were found between 1926 and 1974. Since 1927, the king cheetah was reported five more times in the wild. Although strangely marked skins had come from Africa, a live king cheetah was not photographed until 1974 in South Africa’s Kruger National Park. Cryptozoologists Paul and Lena Bottriell photographed one during an expedition in 1975. They also managed to obtain stuffed specimens. It appeared larger than a spotted cheetah and its fur had a different texture. There was another wild sighting in 1986—the first in seven years. By 1987, thirty-eight specimens had been recorded, many from pelts.

Its species status was resolved in 1981 when king cheetahs were born at the De Wildt Cheetah and Wildlife Centre in South Africa. In May 1981, two spotted sisters gave birth there and each litter contained one king cheetah. The sisters had both mated with a wild-caught male from the Transvaal area (where king cheetahs had been recorded). Further king cheetahs were later born at the Centre. It has been known to exist in Zimbabwe, Botswana and in the northern part of South Africa’s Transvaal province. A recessive gene must be inherited from both parents in order for this pattern to appear- which is one reason why it is so rare.

Other color variations

Other rare color morphs of the species include speckles, melanism, albinism and gray coloration. Most have been reported in Indian cheetahs, particularly in captive specimens kept for hunting.

The Mughal Emperor of India, Jahangir, recorded having a white cheetah presented to him in 1608. In the memoirs of Tuzk-e-Jahangiri, the Emperor says that in the third year of his reign: Raja Bir Singh Deo brought a white cheetah to show me. Although other sorts of creatures, both birds and beasts have white varieties …. I had never seen a white cheetah. Its spots, which are (usually) black, were of a blue colour, and the whiteness of the body also inclined to blue-ishness. This suggests a chinchilla mutation which restricts the amount of pigment on the hair shaft. Although the spots were formed of black pigment, the less dense pigmentation gives a hazy, grayish effect. As well as Jahangir’s white cheetah at Agra, a report of “incipient albinism” has come from Beaufort West according to Guggisberg.

In a letter to “Nature in East Africa”, H. F. Stoneham reported a melanistic cheetah (black with ghost markings) in the Trans-Nzoia District of Kenya in 1925. Vesey Fitzgerald saw a melanistic cheetah in Zambia in the company of a spotted cheetah. Red (erythristic) cheetahs have dark tawny spots on a golden background. Cream (isabelline) cheetahs have pale red spots on a pale background. Some desert region cheetahs are unusually pale; probably they are better-camouflaged and therefore better hunters and more likely to breed and pass on their paler coloration. Blue (Maltese or grey) cheetahs have variously been described as white cheetahs with grey-blue spots (chinchilla) or pale grey cheetahs with darker grey spots (Maltese mutation). A cheetah with hardly any spots was shot in Tanzania on 1921 (Pocock), it had only a few spots on the neck and back and these were unusually small.

Range and habitat

A cheetah in Serengeti National Park, Tanzania.

There are several geographically isolated populations of cheetah, all of which are found in Africa or Southwestern Asia. A small population (estimated at about fifty) survive in the Khorasan Province of Iran, where conservationists are taking steps to protect them. It is possible, though doubtful, that some cheetahs remain in India. There have also been several unconfirmed reports of Asiatic Cheetahs in the Balochistan province of Pakistan, with at least one dead animal being discovered recently.

The cheetah thrives in areas with vast expanses of land where prey is abundant. The cheetah likes to live in an open biotope, such as semi-desert, prairie, and thick brush, though it can be found in a variety of habitats. In Namibia, for example, it lives in grasslands, savannahs, areas of dense vegetation, and mountainous terrain.

In much of its former range, the cheetah was tamed by aristocrats and used to hunt antelopes in much the same way as is still done with members of the greyhound group of dogs.

Reproduction and behavior

Cheetah cub.

Females reach maturity in twenty to twenty-four months, and males around twelve months (although they do not usually mate until at least three years old), and mating occurs throughout the year. A study of cheetahs in the Serengeti showed that females are sexually promiscuous and often have cubs by many different males.

Females give birth to up to nine cubs after a gestation period of ninety to ninety-eight days, although the average litter size is three to five. Cubs weigh from 150 to 300 g (5.3 to 11 oz) at birth. Unlike some other cats, the cheetah is born with its characteristic spots. Cubs are also born with a downy underlying fur on their necks, called a mantle, extending to mid-back. This gives them a mane or Mohawk-type appearance; this fur is shed as the cheetah grows older. It has been speculated that this mane gives a cheetah cub the appearance of the Honey Badger (Ratel), to scare away potential aggressors. Cubs leave their mother between thirteen and twenty months after birth. Life span is up to twelve years in the wild, but up to twenty years in captivity.

Unlike males, females are solitary and tend to avoid each other, though some mother/daughter pairs have been known to be formed for small periods of time. The cheetah has a unique, well-structured social order. Females live alone except when they are raising cubs and they raise their cubs on their own. The first eighteen months of a cub’s life are important; cubs learn many lessons because survival depends on knowing how to hunt wild prey species and avoid other predators. At eighteen months, the mother leaves the cubs, who then form a sibling, or “sib” group, that will stay together for another six months. At about two years, the female siblings leave the group, and the young males remain together for life.

Territories

Males

Males are very sociable and will group together for life, usually with their brothers in the same litter; although if a cub is the only male in the litter then two or three lone males may group up, or a lone male may join an existing group. These groups are called coalitions. In one Serengeti study by Caro and Collins (1987), 41% of the adult males were solitary, 40% lived in pairs and 19% lived in trios.

A coalition is six times more likely to obtain an animal territory than a lone male, although studies have shown that coalitions keep their territories just as long as lone males—between four and four and a half years.

Males are very territorial. Females’ home ranges can be very large and trying to build a territory around several females’ ranges is impossible to defend. Instead, males choose the points at which several of the females’ home ranges overlap, creating a much smaller space, which can be properly defended against intruders while maximizing the chance of reproduction. Coalitions will try their best to maintain territories in order to find females with whom they will mate. The size of the territory also depends on the available resources; depending on the part of Africa, the size of a male’s territory can vary greatly from 37 to 160 km2 (14 to 62 sq mi).

Males mark their territory by urinating on objects that stand out, such as trees, logs, or termite mounds. The whole coalition contributes to the scent. Males will attempt to kill any intruders and fights result in serious injury or death.

Females

Female cheetah and cubs in the Ngorongoro Conservation Area.

Unlike males and other felines, females do not establish territories. Instead, the area they live in is termed a home range. These overlap with other females’ home ranges, often those of their daughters, mothers, or sisters. Females always hunt alone, although cubs will accompany their mothers to learn to hunt once they reach the age of five to six weeks.

The size of a home range depends entirely on the availability of prey. Cheetahs in southern African woodlands have ranges as small as 34 km2 (13 sq mi), while in some parts of Namibia they can reach 1,500 km2 (580 sq mi).

Vocalizations

The cheetah cannot roar, but does have the following vocalizations:

  • Chirping – When cheetahs attempt to find each other, or a mother tries to locate her cubs, it uses a high-pitched barking called chirping. The chirps made by a cheetah cub sound more like a bird chirping, and so are termed chirping.
  • Churring or stuttering – This vocalization is emitted by a cheetah during social meetings. A churr can be seen as a social invitation to other cheetahs, an expression of interest, uncertainty, or appeasement or during meetings with the opposite sex (although each sex churrs for different reasons).
  • Growling – This vocalization is often accompanied by hissing and spitting and is exhibited by the cheetah during annoyance, or when faced with danger.
  • Yowling – This is an escalated version of growling, usually displayed when danger worsens.
  • Purring – This is made when the cheetah is content, usually during pleasant social meetings (mostly between cubs and their mothers). A characteristic of purring is that it is realised on both egressive and ingressive airstream. A purring cheetah can be heard on Robert Eklund’s Ingressive Speech website  or on Robert Eklund’s Wildlife page .

Diet and hunting

A cheetah with impala kill.

The cheetah is a carnivore, eating mostly mammals under 40 kg (88 lb), including the Thomson’s Gazelle, the Grant’s gazelle, the springbok and the impala. The young of larger mammals such as wildebeests and zebras are taken at times, and adults too, when the cats hunt in groups. Guineafowl and hares are also prey. While the other big cats mainly hunt by night, the cheetah is a diurnal hunter. It hunts usually either early in the morning or later in the evening when it is not so hot, but there is still enough light.

The cheetah hunts by vision rather than by scent. Prey is stalked to within 10–30 m (33–98 ft), then chased. This is usually over in less than a minute, and if the cheetah fails to make a catch quickly, it will give up. The cheetah has an average hunting success rate of around 50% – half of its chases result in capture.

Running at speeds between 112 and 120 km/h (70 and 75 mph) puts a great deal of strain on the cheetah’s body. When sprinting, the cheetah’s body temperature becomes so high that it would be deadly to continue; this is why the cheetah is often seen resting after it has caught its prey. If it is a hard chase, it sometimes needs to rest for half an hour or more. The cheetah kills its prey by tripping it during the chase, then biting it on the underside of the throat to suffocate it, for the cheetah is not strong enough to break the necks of the four-legged prey it mainly hunts. The bite may also puncture a vital artery in the neck. Then the cheetah proceeds to devour its catch as quickly as possible before the kill is taken by stronger predators.

The diet of a cheetah is dependent upon the area in which it lives. For example, on the East African plains, its preferred prey is the Thomson’s Gazelle. This small antelope is shorter than the cheetah (about 53–67 cm (21–26 in) tall and 70–107 cm (28–42 in) long), and also cannot run faster than the cheetah (only up to 80 km/h (50 mph)), which combine to make it an appropriate prey. Cheetahs look for individuals which have strayed some distance from their group, and do not necessarily seek out old or weak ones.

A cheetah in pursuit of Thomson’s Gazelle. Ngorongoro Crater, Tanzania.

Interspecific predatory relationships

Despite their speed and hunting prowess, cheetahs are largely outranked by other large predators in most of their range. Because they have evolved for short bursts of extreme speed at the expense of both power and the ability to climb trees, they cannot defend themselves against most of Africa’s other predator species. They usually avoid fighting and will surrender a kill immediately to even a single hyena, rather than risk injury. Because cheetahs rely on their speed to obtain their meals, any injury that slows them down could essentially be life threatening.

A cheetah has a 50% chance of losing its kill to other predators. Cheetahs avoid competition by hunting at different times of the day and by eating immediately after the kill. Due to the reduction in habitat in Africa, Cheetahs in recent years have faced greater pressure from other native African predators as available range declines.

The cheetah’s mortality is very high during the early weeks of its life; up to 90% of cheetah cubs are killed during this time by lions, leopards, hyenas, wild dogs, or even by eagles. Cheetah cubs often hide in thick brush for safety. Mother cheetahs will defend their young and are at times successful in driving predators away from their cubs. Coalitions of male cheetahs can also chase away other predators, depending on the coalition size and the size and number of the predator. Because of its speed, a healthy adult cheetah has few predators.

 
 

African Lion

22 Apr
African Lion

African Lion

Lions are the only cats that live in groups, which are called prides. Prides are family units that may include up to three males, a dozen or so females, and their young. All of a pride’s lionesses are related, and female cubs typically stay with the group as they age. Young males eventually leave and establish their own prides by taking over a group headed by another male.

Only male lions boast manes, the impressive fringe of long hair that encircles their heads. Males defend the pride’s territory, which may include some 100 square miles (259 square kilometers) of grasslands, scrub, or open woodlands. These intimidating animals mark the area with urine, roar menacingly to warn intruders, and chase off animals that encroach on their turf.

Female lions are the pride’s primary hunters. They often work together to prey upon antelopes, zebras, wildebeest, and other large animals of the open grasslands. Many of these animals are faster than lions, so teamwork pays off.

After the hunt, the group effort often degenerates to squabbling over the sharing of the kill, with cubs at the bottom of the pecking order. Young lions do not help to hunt until they are about a year old. Lions will hunt alone if the opportunity presents itself, and they also steal kills from hyenas or wild dogs.

Lions have been celebrated throughout history for their courage and strength. They once roamed most of Africa and parts of Asia and Europe. Today they are found only in parts of sub-Saharan Africa, except for one very small population of Asian lions that survives in India’s Gir Forest.

 

Leopard

22 Apr

The leopard (pronounced /ˈlɛpərd/), Panthera pardus, is a member of the Felidae family and the smallest of the four “big cats” in the genus Panthera, the other three being the tiger, lion and jaguar. Once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, the leopard’s range of distribution has decreased radically because of hunting and loss of habitat. It is now chiefly found in sub-Saharan Africa; there are also fragmented populations in Pakistan, India, Indochina, Malaysia, and China. Because of its declining range and population, it is listed as a “Near Threatened” species by the IUCN.

Northern Chinese Leopard

Northern Chinese Leopard

Compared to other members of the Felidae family, the leopard has relatively short legs and a long body with a large skull. It is similar in appearance to the jaguar, but is smaller and more slightly built. Its fur is marked with rosettes similar to those of the jaguar, but the leopard’s rosettes are smaller and more densely packed, and do not usually have central spots as the jaguar’s do. Both leopards and jaguars that are melanistic (completely black or very dark) are known as black panthers.

The species’ success in the wild is in part due to its opportunistic hunting behavior, its adaptability to habitats, its ability to run at speeds approaching 58 kilometres per hour (36 mph), its unequaled ability to climb trees even when carrying a heavy carcass, and its notorious ability for stealth. The leopard consumes virtually any animal it can hunt down and catch. Its habitat ranges from rainforest to desert terrains.

Leopards are graceful and powerful big cats closely related to lions, tigers, and jaguars. They live in sub-Saharan Africa, northeast Africa, Central Asia, India, and China. However, many of their populations are endangered, especially outside of Africa.

The leopard is so strong and comfortable in trees that it often hauls its kills into the branches. By dragging the bodies of large animals aloft it hopes to keep them safe from scavengers such as hyenas. Leopards can also hunt from trees, where their spotted coats allow them to blend with the leaves until they spring with a deadly pounce. These nocturnal predators also stalk antelope, deer, and pigs by stealthy movements in the tall grass. When human settlements are present, leopards often attack dogs and, occasionally, people.

Leopards are strong swimmers and very much at home in the water, where they sometimes eat fish or crabs.

Female leopards can give birth at any time of the year. They usually have two grayish cubs with barely visible spots. The mother hides her cubs and moves them from one safe location to the next until they are old enough to begin playing and learning to hunt. Cubs live with their mothers for about two years—otherwise, leopards are solitary animals.

Most leopards are light colored with distinctive dark spots that are called rosettes, because they resemble the shape of a rose. Black leopards, which appear to be almost solid in color because their spots are hard to distinguish, are commonly called black panthers.

 
No Comments

Posted in Leopard