| Writer's Note |
[Nov. 14th, 2005|10:48 am] |
As you've probably noticed, EYBH went kinda dead. It started on the day we had a long net outage, and then stuff just kinda built up. I do not intend to let things peter out, so I wanted to reassure my faithful readers of that.
And I'll also very willingly take requests. A few notes on that; I prefer to space out birds of similar type, so since I just did a parrot, I'd like to wait a while before doing another. Feel free to suggest whatever you'd like to see; just don't be concerned if I don't get to it at the same pace as other suggestions.
And here's a little list of requests and birds I've got plans to feature myself, in no particular order:
Wedge-tailed Eagle
Eurasian Jay
Northern Saw-whet Owl
Wood Duck
Mountain Bluebird
Common Loon/Great Northern Diver
California Condor
Harris' Hawk |
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| Expand Your Birdy Horizons: Spruce Grouse |
[Nov. 8th, 2005|08:24 pm] |
On a suggestion by ![[info]](http://l-stat.livejournal.com/img/userinfo.gif) miwasatoshi, today I focus on Falcipennis canadensis, the Spruce Grouse.
A bird of coniferous forests of North America, the Spruce Grouse is found mostly within Canada and Alaska, with the southern end of its range straying into the northern reaches of the United States. A typical gamebird, it is a member of the Phasianidae family. It is also aptly named, for a primary foodsource for this bird in the winter is the needles of spruce and other conifers. It is even able to enlarge its digestive tract in winter, to allow it to process more food with the demands of the season Females are cryptically colored in a pattern of browns, greys, and whites, while males have a more striking appearence, with red wattles over their eyes, intricate black and white barring on their chests, and white-tipped tailfeathers.
Like many gamebirds, the Spruce Grouse male has an intricate courtship display involving fanned tailfeathers, ruffled neckfeathers, and loud wingclaps that sound like gunshots. The female lays five to nine eggs in a moss-lined hollow, incubating them for up to three weeks. The chicks are precocial and generally fledge in ten days. The chicks feed on insects to provide the necessary nutrients for their quick growth, but soon add berries, ferns, and other plant material to their diets.
Spruce Grouse are hunted seasonally in parts of their range, though in others they are considered locally threatened or endangered. With good husbandry, hunting has little ill effect on populations; the real threat is habitat destruction, as these birds are nonmigratory and often will not stray far from where they hatched in their lifetimes. Another threat comes in the form of roads; Spruce Grouse learn that roads provide a supply of gravel they can use as grit to aid in digestion, but it also puts them at risk of vehicle collisions.
Inconspicuous but also with a reputation for being unafraid, the Spruce Grouse is symbolic of the northern lands it inhabits. |
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| Expand Your Birdy Horizons: Yellow-billed Magpie |
[Nov. 7th, 2005|08:24 pm] |
Today the focus is on a true member of the Corvidae family, a Californian specialty found only in the Central Valley and Coast Ranges. Pica nuttalli, the Yellow-billed Magpie.
The Yellow-billed Magpie is one of two corvid species endemic (or exclusive) to California; the other is the Island Scrub-Jay, found only on Santa Cruz Island. Closely resembling the more familiar Black-billed Magpie Pica hudsonia, the Yellow-billed differs in the obvious coloration of its bill and facial patch, and also by being a bit smaller than its cousin. Otherwise, it shares the same basic appearence, glossy iridescent black with white. To find this corvid, one must visit either the Central Valley or the central coast of California. It favors open woodlands and in some parts of its range it is not shy of humanity, found within dense human populations; in others, it has declined seemingly due to habitat loss. It requires oak savanna woodland, and preservation of such habitat is essential for its continued survival. It is a nonmigratory species; climate within its range is temperate enough year-round.
In the past, the greatest threat to the Yellow-billed Magpie's survival was shooting and poisoning; that threat has declined thanks to increased protections and a better understanding of the magpie's habits and behavior. Populations have been relatively stable in recent years, though biologists fear that is about to change from the threat of disease. West Nile Virus has only started to spread through California, and corvids are especially suceptible to this disease; crow and jay populations throughout the country have crashed after the disease reached them. Many fear that WNV will have a decimating effect on this Californian specialty, and statewide surveys on bird deaths due to WNV are watching the situation closely. It has been made even more complicated with fears of avian flu reaching the United States and spreading through native birds already weakened by West Nile Virus. Biologists sincerely hope that this unique bird will be able to withstand both of these devastating diseases and stay flying in California's skies. |
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| Expand Your Birdy Horizons: Military Macaw |
[Nov. 6th, 2005|03:10 pm] |
Today the avian focus is on a bird with a range from Mexico into northern reaches of South America, a bird who earned his name for his green feathers but is more than "just a green bird." Introducing Ara militaris, the Military Macaw.
The smallest of the large macaws, the Military is still an impressive bird, with a length of approximately 28 inches from beak to tailtip. It is often overlooked in favor of its flashier cousins, such as the Scarlet and the Blue and Gold, but dismissing this magnificent macaw is a disservice. Green is indeed the primary color of its plumage, but it's many shades of green, from yellow-hinted olive into brilliant emerald into deep forest, with accents of turquoise to blue in the wings and a bushy red "mustache" over the black beak. The Military's tailfeathers are spectacular, starting as a ruddy red and then turning to a brilliant light blue. The Buffon's or Great Green Macaw, Ara ambigua, is very similar in appearence to the Military, but is notably larger at about 34 inches long, and also has a lighter green color overall.
Despite the reputation macaws have as rainforest birds, the Military Macaw is among those in the group that prefer semi-arid habitat, such as dry forests along streams and open woodlands. This brings one of the subspecies quite close to the US/Mexico border, though generally they range about 200 miles south of Brownsville, Texas. They are highly conspicuous, both for their loud calls and for their preference for perching on high and outer branches. Like most South American parrots, its diet consists of fruit, vegetation, and nuts and seeds. Military Macaws share the psittacine trait of being highly social, often flocking in groups as large as forty, and often engage in affectionate behavior among flockmates such as allopreening (preening a flockmate). For breeding purposes, Military Macaws nest in cavities in old trees, such as abandoned woodpecker nests which they may enlarge for their own use.
Military Macaws are classified as Vulnerable. Like many parrots, their populations are threatened by habitat loss and by the illegal bird trade. Since 1975, trade in endangered species such as Military Macaws has been controlled by CITES (the Convention on International Trade in Endangered Species). Most Military Macaws found in aviculture were imported before CITES (given their long lifespan, 30-50 years and potentially up to 80 years or more) or are captive-bred birds, though illegal trapping and importation does still occur despite the best efforts of authorities. Ecotourism has helped raise money and awareness of the plight of birds like the Military Macaw, and offers the priceless sight of wild parrots on the wing. |
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| Expand Your Birdy Horizons: Kori Bustard |
[Nov. 5th, 2005|08:13 pm] |
Today I focus on the heaviest bird capable of flight: Ardeotis kori, the Kori Bustard.
A distinctive Old World bird family, bustards are believed to have diverged from cranes. A few members of the bustard family are termed "heaviest flying bird," but the title is more often given to the savanna-dwelling Kori Bustard than its cousins, the Australian Bustard and the Great Indian Bustard, who usually rival the title. Of course, it is the male bustard that earns this recognition; females are notably smaller than the males, which are on average four feet tall and weigh up to 40 lbs. Given its weight, the Kori Bustard is indeed barely able to fly, and instead spends most of its time on the ground foraging for insects, lizards, and tender shoots of vegetation. It has a rather cryptic pattern of browns and greys, but its markings are rather striking when viewed closely.
The Kori Bustard has a divided range, with a population in Kenya and Tanzania, and another in the South African region. It is regarded as widespread within its range, but it is not exactly common, with most birds tending to forage alone. The male has a rather spectacular courtship display wherein he expands his neck and makes loud booming sounds while raising his tailfeathers. The male will mate with several females, and the females will tend to the eggs and chicks alone.
A very notable bird of the African Savanna, the Kori Bustard is, like the rest of its family, very much an open country bird, lacking an opposable hind toe with which it might perch. It actually becomes a perch for several species of bee-eaters (such as Carmine Bee-eaters) which will ride on the back of a bustard, and then take off to hawk insects startled into the air by the bustard's progress through the grasses. Unmistakeable in flight, this "heaviest flying bird" is well-adapted to its surroundings. |
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| Expand Your Birdy Horizons: Cedar Waxwing |
[Nov. 4th, 2005|04:13 pm] |
Today I feature an avian well-associated with the fade of autumn into winter in North America. Introducing Bombycilla cedrorum, the Cedar Waxwing.
A sleek brown bird with a backswept crest, the Cedar Waxwing is one of two North American representatives of its genus, the other being the similar Bohemian Waxwing. Distinctions can be made between the two species based primarily on the yellow underside in the Cedar as opposed to greyish in Bohemian. A third member, the Japanese Waxwing, is obviously an Asian species. It is a medium-sized bird somewhat smaller than an American Robin. Waxwings are so named for the odd red tips found on the secondaries of some birds, which appear to serve some sort of signalling function; their purpose isn't entirely clear. What is known is that Waxwings are some of the few temperate-dwelling birds that are almost entirely frugivorous, eating berries and fruit almost exclusively, though they also feed on insects during the summer. Due to their dependence on fruit, they have a late nesting season in order to have a large supply of berries available to nestling, and birds will travel in large flocks of forty or more to descend on berry-laden trees and bushes during the fall and winter. Cedar Waxwings have achieved a reputation for being voracious eaters due to their ability to strip trees of their berry crop in a short amount of time, but they are also charmingly courteous to one another; several Cedar Waxwings sitting in a row will pass a berry or insect from one to another up and down the row until finally one bird decides to swallow it. They have very swift digestive systems, an important feature when eating fruit; some fermented fruits will make them "drunk," and can even kill them if they injest too much.
Cedar Waxwings are fairly widespread throughout North America. They are fairly northerly in their breeding range, and exhibit little territoriality except for the nest site itself. A bulky open cup holds 4-5 eggs that are tended by both parents. Nestlings are at first fed insects, then berries. Fledglings exhibit streaky plumage in contrast to the smooth, silky coat of mature adults.
During the cooler months of the year when food sources are limited, Cedar Waxwings form their large flocks, migrating southward if necessary to find the berries they feed on. Therefore many have come to regard these birds as signs of autumn and winter as they descend in flocks on berry crops with their high, clear "dhzee!" calls. This sleek brown berry-eater is a highly distinctive bird and a favorite of many birdwatchers. |
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| Expand Your Birdy Horizons: Inca Tern |
[Nov. 3rd, 2005|01:36 pm] |
Shifting focus to the Pacific Coast of South America, I introduce to all you crazy readers of mine one of the world's most distinctive seabirds; Larosterna inca, the Inca Tern.
All-over dark slate, with black primaries, white wing edges, red beak and feet, yellow gape wattles, and streaming white whiskers (worn by both males and females), the Inca Tern certainly stands out among terns and gulls, which typically wear plumage in a plain white-grey-black palette. It is a resident of the rocky Pacific Coastline of South America from Peru to Chile, where it nests in sheltered cliffs rather than on open ground like most terns, often reusing old Humboldt Penguin nests. Typically they feed on anchovies and small lobsters, hovering 50 feet or so above the water before plunging for their prey. Accomplished fliers, Inca Terns are not very good swimmers, and tend to float on the water's surface.
Aerial displays are part of courtship in Inca Terns, as well as presenting gifts of fish by the male. The female lays one to three eggs in their sheltered nest, and both parents take turns incubating and tending to the chicks until they fledge at about seven weeks. Juvenile Inca Terns are greyish-brown in coloration and attain their adult plumage at about the age of one year.
The "Zarcillo," as it is called in its home range, is a very elegant resident of the coastline, cohabiting with native penguins without competition, as the penguins dive much deeper for fish. They are regarded as fairly common and are considered Not Globally Threatened, though individual populations may be at risk for factors such as pollution and overfishing.
A favorite seagoing species of birders visiting the Peruvian and Chilean coasts, the Inca Tern is also found in zoos worldwide, certainly drawing attention for their striking appearence. |
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| Expand Your Birdy Horizons: Australian Magpie |
[Nov. 2nd, 2005|11:01 am] |
For today's avian feature (which is dedicated to rosequoll), I bring to you the brash minstrel of the land Down Under, Gymnorhina tibicen, the Australian Magpie.
Despite its name, the Australian Magpie is not a close relative of the more widespread Black-billed Magpies of Eurasia and North America (Pica pica and P. hudsonia); it is more closely related to butcherbirds and currawongs than crows and jays. Its similar pattern of black and white reminded European settlers of the magpies of their homeland, in a manner similar to how the American Robin Turdus migratorius was named for the Robin Erithacus rubecula due to both being garden birds with red chests, despite not being close relatives. The Australian Magpie's voice is not at all like the "engine turning over" sound of the Black-billed Magpie, but an honestly beautiful and intricate flute-like song that makes them a delight to hear.
The exact pattern of markings exhibited by Australian Magpies varies within their range, but all have white beaks fading to black and reddish eyes. Some are known as "black-backed" while others are "white-backed" subspecies. Formerly some were regarded as separate species, but now all Australian Magpies are considered to be conspecific, as they freely breed among different subspecies populations.
Australian Magpies are common and conspicuous in their range, found in parks and open woodlands throughought Australia and seeming equally comfortable in the bush or in the city. They feed on insects, worms, lizards, and occasionally carrion, requiring open space to forage and eucalyptus stands for nesting. They are gregarious by nature, forming clans of up to 20-some birds that defend their territory year-round. When spring arrives, they truly make their presence known, becoming fiercely protective of their nesting area and "swooping" on any perceived threat, including humans. Some estimates indicate that 3/4s of Australians have been attacked by a magpie at some point in their lives. While at first it seems amusing, the birds can cause scalp and facial injuries in their attacks, and it is especially frightening to children; this has led to programs that post signs warning passersby that nesting magpies are near and indicating how best to protect one's self (such as wearing sunglasses on the back of the head, as most attacks are made from the back). Especially aggressive magpies are occasionally captured and relocated, rarely even destroyed. The magpies are most territorial for six weeks while they protect their eggs and nestlings, and once the chicks fledge, attacks drop off sharply.
With their bold and tenacious behavior and their beautiful song, the Australian Magpie is a study in contrasts in personality just as much as it is in its black and white plumage. |
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| Expand Your Birdy Horizons: Anna's Hummingbird |
[Nov. 1st, 2005|01:45 pm] |
After a long absense, birdoftheday is back! Hopefully. :D In place of the NaNoWriMo challenge, I've decided to aim to update this blog once a day for the month of November. Hopefully all goes well and I can keep this active. :)
And what better bird to kick off this revival of the blog but a member of a group of birds associated with rebirth and regeneration? Not to mention the fact that it's one of my favorite birds. I introduce to you Calypte anna, the Anna's Hummingbird.
Like most of the hummingbirds that spend time in North America, the Anna's Hummingbird is predominantly green; its underside is more of a greyish color with some metallic edging. The adult male's brilliant magenta crown and gorget are a primary identification feature; the congenic Costa's Hummingbird has a violet crown and gorget, with longer extension on the gorget. Females are duller in coloration, lacking the brilliant magenta except in a small patch on the throat.
Anna's Hummingbirds have the distinction of being the only hummingbird species with a winter range primarily in the United States (though Costa's and Allen's Hummingbirds also have winter ranges that include the United States). In fact, Anna's Hummingbirds are year-round residents in much of their range, which spans most of the Pacific Coast of the United States into southeastern Alaska. While most other hummingbirds migrate into Central and South America in the fall, Anna's will stay in much the same area as their breeding range, taking advantage of the moderated coastal climate and the spread of cultivated gardens, supplimenting their diet with tree sap from wells created by sapsuckers when nectar is scarce. What migration they undertake is primarily altitudinal; they descend from higher elevations into the valleys when the weather cools. Residents of the Pacific Coast therefore can enjoy hummingbird garden visitors year-round, even if snow falls, as hummingbirds are able to enter a state called torpor where their functions slow down if they don't have the energy stores to remain alert through the night.
The early bloom of the red gooseberry provides abundant food sources for the Anna's, which allows it to begin breeding far earlier than any other North American hummingbird, starting even as early as December. Other favored plants include bottlebrush, thistle, sage, fuschia, bee balm, and other similar plants. It is a misconception that hummingbirds feed only from red flowers; they visit red flowers first because other pollinators, like bees, tend to visit yellow and white flowers first. It optimizes their nectar collection if they visit flowers likely to still contain nectar. Another misconception regards their diet; nectar is not their only food source. In fact, Anna's Hummingbirds have the highest percentage of insects in their diet of any North American species, catching them in the air or within flowers.
Courtship in the Anna's Hummingbird is rather spectacular. A male defines his territory and claims it by perching in a high, conspicuous position. From there he sings his scratchy, squeaky song while turning his head to best display his gorget and crown; the feathers shine magenta only when seen head-on, and otherwise appear brown or blackish. (Most hummingbirds do not have a song; their tiny size and requirement for large pectoral muscles has caused the syrinx to become weak and essentially limits them to chirps and squeaks.) When displaying for a female, the male Anna's will climb into the air, singing his song, then make a J-shaped dive. At the bottom of the dive, a special notch in his retrices (tailfeathers) makes a loud screech that is apparently quite sexy to female Anna's. He will often repeat this display a few times before either copulating or returning to his perch, and this is the extent of the male's involvement in breeding.
The female builds a nest out of spider silk and plant down, plastering the outside with scales of lichen to help camouflage it. Typically two eggs are laid, hatching within two weeks; the naked nestlings do not have long beaks upon hatching, but their beaks grow quickly, as do their feathers. As early as three weeks after hatching the young may leave the nest, though they will remain dependent on their mother for feeding for a while, and presumably also learn suitable food sources in this time. Juvenile hummers quickly develop territorial behavior once they are confident enough to feed on their own.
Anna's Hummingbirds are common but never ordinary visitors to backyard gardens and feeders in their range. To attract them (or any other hummingbird species), a feeder with some red coloration is enough; red dyes in the nectar have not been confirmed to have a detrimental effect on hummingbird health, but as hummingbirds will readily drink clear nectar, it's best safe than sorry. The feeder should not be overly ornamented, to allow for easy cleaning (which should be done once a week, more often in hot weather). Feeders with the nectar resevoir above the drinking ports tend to leak and attract bees and ants; a dish-like reservoir can cut down on that problem. Like all hummingbirds, Anna's are extremely territorial and one individual may lay claim to an entire feeder, chasing away all others, though at certain times of the year they seem to set aside their differences to feed together.
A brilliant, jewel-like bird with a big attitude, the Anna's Hummingbird is a treasured visitor that seems more than just a little bit magical. |
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| Expand Your Birdy Horizons: Ivory Gull |
[Apr. 6th, 2005|06:56 pm] |
It's been a long time, and I apologize profusely. Real Life just got in the way of writing these essays. Let's start things up again with what may be the most beautiful gull in the world: Pagophila eburnea, the Ivory Gull.
To people used to associating gulls with garbage dumps, parking lots, and wharves, the idea of an elegant white gull inhabiting the icy lands of the Arctic seems almost too beautiful to be a real gull. But even if it doesn't frequent dumps and docks, it's still a scavenger, following polar bears and arctic foxes to pick from the carcasses those predators leave behind. It does also feed on fish and crustaceans, as well as beached whales and seals. The Ivory Gull is the only gull with all-white plumage as an adult; juveniles have black-spotted plumage that is also very striking, especially against their black legs. Juveniles can be identified by the lack of any grey, brown, or buffy colors in their plumage.
Ivory Gulls are birds of the High Arctic, living where there is permanent pack ice and open water. In some winters, juveniles may wander further south to locations such as the Atlantic Coast of southern Canada and the US Northeast, as well as the Great Lakes, when food is scarce, but adults are rarely encountered that far south. The greatest concentration of Ivory Gulls is thought to live in northern Eurasia, with other populations in Greenland and North America. To breed, Ivory Gulls choose remote locations devoid of most other animals to make their nests, from rock outcroppings to steep ice cliffs to gravel-covered islands. Up to 150 pairs will form colonies to breed in the same location. Nests are fashioned of moss, lichen, and grasses, and both parents will incubate the 1-3 olive-colored eggs for their 25-day incubation period. Ivory Gulls are very intolerant of disturbance during their breeding season, and are quick to abandon nests to the slightest perceived threat, such as low-flying aircraft. Generally, their preference toward remote, icy areas to breed has protected them, but recent human encroachment endangers their nesting success. When their eggs hatch, silvery-down covers the chicks, who attain full feathering within 11 days and reach breeding age when they attain white plumage, thought to be two years.
Polar bears and arctic foxes are known to feed on Ivory Gull eggs and chicks, and any human encroachment is also a threat to the species' survival, given their low tolerance for disturbance when they breed. By far the greatest risk to the Ivory Gull is oil spills, which can be locally disastrous. However, the populations appear to be stable, so for now this reclusive gull remains a rare but not dangerously scarce sight to birders entranced by their white elegance. |
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| Expand Your Birdy Horizons: Rockhopper Penguin |
[Mar. 25th, 2005|12:36 pm] |
I know, I've been incredibly delinquent with Bird Of The Day postings, for which I really apologize. Life kinda overwhelmed me for a bit.
Today I present to you Eudyptes chrysocome, the Rockhopper Penguin.
Often called simply Rockhopper or even Rockie, this penguin obviously gets its name from its method of locomotion, jumping from rock to rock on the shorelines that they prefer with their feet together; they can hop four to five feet, which is impressive for a bird only two feet tall. They do also waddle in the classic penguin stride, but that isn't very sensible when they need to climb cliffs. A member of the crested penguin group, the Rockhopper can be distinguished by the browlike crests of yellow feathers above its bright red eyes; all other crested penguins have darker eyes. The rest of its body is a fairly penguin-typical black on top, white on the bottom, which serves to help hide this swimming bird when it's in the water; predators looking from above only see a dark shape against the dark deep waters, while predators below see a light shape against the light surface. However, some leucistic (lacking dark pigment) rockhoppers have been recorded. Rockhoppers have pink webbed feet with sharp claws for grip on rocks.
All penguins are found naturally only in the Southern Hemisphere, though some are tropical birds, such as the Galapagos Penguin. The Rockhopper, however, is circumpolar in range, living on subantarctic islands off South America, Africa, and Australia/New Zealand. Their diet consists of small crustaceons (krill), small squid, and occasionally fish that they catch while swimming. Their stubby feet and tail are used as rudders as they swim, which looks far more like flying underwater as they use their flipper-like wings.
During the October-April mating season (the warmest part of the year in the Southern Hemisphere), Rockhoppers gather in large colonies, making "ecstatic vocalizations" to attract a mate. Males also vigorously shake their heads to cause their crests to form a "halo" momentarily. Rockhoppers form pairs but breed together in large colonies (up to one hundred thousand pairs) to help protect their eggs and chicks from predation by birds such as skuas and Snowy Sheathbills. Colonies are located on cliff-faces and rocky terrain, sometimes with vegetation nearby, but established colonies tend to wear it away. The female lays two eggs in a simple nest of stones and sticks, but only the largest is successfully incubated and raised; it is theorized that laying two eggs helps Rockhoppers protect their single chick from predation by offering a "dummy egg" to predators. One subspecies of Rockhopper, the Southern, will occasionally succeed in raising both eggs in good years, but success rates on the whole are highly variable, and for each pair that raises both, another pair fails to raise any.
The females take the first incubation shift while the males go out to sea to forage, having fasted for four weeks during courtship and mating. The female then goes out when her mate relieves her, and her return tends to coincide with the hatching of the egg so that she can feed the chick; sometimes, however, the chick must survive on yolk reserves for up to a week before she returns. At this point the male guards the chick, while the female hunts for herself and her chick, though the male can feed the chick on "penguin milk" if his mate is unsuccessful in finding food. This stage lasts about two weeks, after which the chicks form "creches," small groups of other youngsters, which they stay in for protection while both of their parents go out to forage. They "fledge" at about 10 weeks of age, shedding their greyish-brown chick down for plumage much like their parents, but lacking the bold yellow crests, which develop slowly over the course of four years as they mature to breeding age. Now feeding and fending for themselves, the chicks are left alone for good as their parents prepare to molt new feathers and build up fat reserves. After their molt (in March), they spend the winter at sea.
Rockhoppers are regarded as the most aggressive penguin species; they will attack and peck anything that ventures near them when they're incubating, from other Rockhoppers, predatory birds trying to take an egg or chick, or unoffending wings of nesting albatross neighbors. However, they are tender with their mate, often engaging in allopreening.
Rockhoppers are preyed on by Blue Sharks, Leopard Seals, and Fur Seals. Many species of birds, such as skuas, petrels, and gulls, will feed on eggs and chicks. Rockhopper numbers are also declining in some areas of their range; the cause appears to be rising water temperatures, which diminishes their food supply. Oil spills also have an impact on the Rockhoppers. The IUCN Redlist classifies them as Vulnerable due to the decline in numbers; it is estimated that 3,500,000 breeding pairs exist, mostly in the Falkland Islands. However, with the increase of ecotourism to the Falklands and other islands the Rockhopper inhabits, conservation awareness is rising for this distinctive crested penguin. |
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| Expand Your Birdy Horizons: Lappet-faced Vulture |
[Mar. 19th, 2005|07:18 pm] |
Ugly fowl with distasteful diets, or underappreciated undertakers making the world cleaner? Introducing a member of a much-maligned group of birds, Torgos tracheliotus, the Lappet-faced Vulture.
Vultures as a whole are birds with much symbolism and misconceptions attached; harbingers of death, ill omens, foul fowl that feed on the dead, lazy creatures that can't be bothered to kill their own food. In actuality, vultures perform a valuable service, one that very few others would care to take up. Cleaning up carcasses isn't nearly as glamorous as seizing a fish from the water or taking a bird in the air as other Accipitrids do, but without the vulture cleanup detail, there would be far more disease from rotting flesh...and the world would probably smell a lot stronger. There are actually two very different groups of vultures, the Old World Vultures of Eurasia and Africa, and the New World Vultures, which include Turkey Vultures and condors. The New World Vultures are actually more closely related to storks than to hawks, despite similarities of form and function--but more on that when I profile a New World Vulture.
The Lappet-faced Vulture is mostly brown with a white underside. It gets its name from the folds--or lappets--of skin on its bare face; it is also called the Nubian Vulture. Ranging throughout most of Africa as well as the southern coasts of the Arabian Peninsula, it is Africa's largest vulture, with a wingspan of 9 feet. It's also one of the shyest and most solitary, preferring to be alone or at the most in pairs or family groups, whereas many other vultures of its range are rather gregarious and bold. The bare skin of its face is an adaptation for feeding on and in carrion; no feathers means nothing to get matted with blood, and a bird can't easily preen its head. They do, however, bathe frequently at waterholes. With their powerful beaks, Lappet-faced Vultures are often the only vultures able to tear open a carcass, and so they take precendence over any others gathered at a meal. They've also been known to fend off jackals that try to steal the carcass. They find their meals by sight, though occasionally they find food by the other vultures already congregated at a carcass. Their beaks also allow them to feed on tough parts of a carcass that other vultures can't handle. When carrion is scarce, they are agile enough to seize their own prey, mostly small mammals, but it also takes catfish from drying riverbeds.
Both sexes build a nest in a platform of sticks in the top of a thorny tree, and then the female Lappet-faced lays one white, brown-blotched egg. The egg is incubated by both sexes for up to 55 days. After four months of care, the chick is fledged, but may be cared for by the parents for up to a year; this long period of parental care means that they don't breed every year.
Unfortunately, the Lappet-faced, as well as many other African vultures, is suffering decline. Often poisoned or shot by humans believing it to be unhygenic, it also suffers from electrocution by the unfamiliar high voltage towers being erected in developing areas. Also, it depends heavily on Spotted Hyenas to break down pieces of bone in carcasses, which it feeds to its chicks as a source of calcium; with the hyena also being persecuted and driven out of many areas, the Lappet-faced Vulture no longer has access to the small pieces of bone, and so the chicks often suffer from weak bones as a result of low calcium intake. Because of its declining population, it is regarded as a Vulnerable species according to the IUCN Redlist. Programs are underway in its range to protect them from persecution and educate the human population as to their very important niche; ironicly, in the "unhygenic" vulture's decline, there has been a rise in diseases found in and spread from decaying carcasses with no animal cleanup crews to take care of them. Hopefully this great bird of the arid lands can bounce back from its persecution and return to the skies. |
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| Expand Your Birdy Horizons: Japanese White-Eye |
[Mar. 18th, 2005|04:08 pm] |
A small oriental songbird, I now introduce Zosterops japonicus, the Japanese White-Eye.
Males and females of this small (4.5 inches long) species have the same appearence, an olive-yellow front and top fading into dusky brown with a pale underside. It gains its name for the ring of white feathers around its eyes, which is broken in the front by a dark line. It is found in Eastern Asia, including Japan, and has also been introduced to the Hawai'ian Islands since 1929. In Japan, it is known as Mejiro, which translates to "white-eye."
Favoring open forests and gardens, the White-Eye is considered a common bird within much of its range, and indeed called the most common bird of Hawai'i. Naturally, it would appear in anime and manga as a widespread and beloved Japanese bird. It is an obligate nectivore, with nectar forming a large part of its diet, though it also feeds on insects and fruit. Arboreal with strong flight, it spends little time on the ground, preferring to cling to foliage. White-Eyes are gregarious birds, forming mixed-species flocks outside the breeding season, and siblings and extended family members will roost together. Described as nervous, it is very energetic and rarely stays still. Flocks will even team up to mob owls and other predators.
In the breeding season, the male advertises his territory by singing, up to 20-40 minutes at dawn and sporadicly in the day. A pair will often preen each other, termed "allopreening," to strengthen the pair bond. A cup-shaped nest is woven of moss, grass, lichen, spiderweb, and other materials, and the female lays 3-5 pale blue eggs. Both sexes incubate, using a "brood patch" of bare skin that both male and female exhibit. The altricial young are fed first on insects, then fruits. They fledge 10-12 days after hatching, their plumage developing rapidly to the point that they are indistinguishable from adults, with a full eye-ring, at 30 days. The juveniles will be cared for by the parents for 15-20 days after fledging, at which time the parents will often start a new nest and chase the brood away.
White-Eyes have a long history in some areas as being among the most available, peaceful, hardy, and inexpensive of passerines kept in aviculture. It has been regarded somewhat as an oriental version of the canary and kept as a cage bird. It is also a favored garden bird, given offerings of cut fruits to entice them into yards, where they offer natural control of noxious insects. In its quest for nectar, it also serves as a pollinator of many plants. Because of its extended breeding season and adaptability, the energetic little Mejiro is not considered endangered. |
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| Expand Your Birdy Horizons: Groove-billed Ani |
[Mar. 17th, 2005|08:17 pm] |
"What do you get when you cross a parrot with a grackle?" asked a birder. The answer is Crotophaga sulcirostris, the Groove-billed Ani.
Though it hardly seems to resemble other cuckoos (like the Greater Roadrunner) except by its very long tail, the Groove-billed Ani is indeed a Cuculiform, exhibiting the two-forward, two-back toe design of the rest of that family. It is a jay-sized, slender bird, with bronzy black feathers, found in a range that normally extends from South Texas to northern South America. Its close relative, the Smooth-billed Ani, obviously differs in bill structure, and is found in Florida, the Caribbean, and parts of northern South America. The Groove-billed Ani displays ridges and grooves in its large beak, which are not as prominant in younger birds. Its tail is fully half of its length, and seems to be "loosely attached," often hanging straight down from its body, and bobbing as it flies.
Groove-billed Anis are very social birds, even nesting communally. Two to five breeding pairs gather and the females lay 3-4 bluish eggs in one large stick nest. All members of the group incubate and care for the young, showing no discrimination or bias in regard to their own genetic offspring and those of other pairs. This makes anis among the most successful polygamous birds.
Feeding mainly on insects, the ani forages on the ground. It prefers scrub and agricultural lands, especially those with cattle where it can feed on the flies attracted by livestock. It is also found near marshes and river banks, where it enjoys sunning in tall trees. In Mexico and Central America, the bird is called "Tijo," presumably after its flight call. |
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| Expand Your Birdy Horizons: Harpy Eagle |
[Mar. 16th, 2005|01:08 pm] |
One of the largest eagles and a fearsome predator of the rainforest, I now introduce Harpia harpyja, the Harpy Eagle.
A magnificent crested raptor, the Harpy Eagle ranges in Central America and South America, living within the rainforests. They once ranged into southern Mexico, but have since been nearly extirpated from the northern part of their range. The sexes look alike, with the female larger than the male. A female Harpy Eagle can weigh up to 18 pounds and be 36-40 inches from beak to tailtip. Their wings are short to allow them to maneuver through trees and thick cover, but they still span an impressive six feet Though there are eagles that are heavier and eagles with greater wingspans, what makes the Harpy Eagle so fearsome is its feet and talons. As large as an adult man's hand, the claws themselves are comparable in size to those of grizzly bears or tigers. It is with those massive feet that it takes its prey, which consists of sloths and monkeys (about 2/3 of its diet), as well as Kinkajous, Coatis, Red Brocked Deer, and reptiles such as snakes and iguanas, as well as occasional parrots. In pursuing prey, they can reach speeds of 20-30 mph through the rainforest and 50 mph in open sky. Primarily they choose to ambush their prey rather than chase it, as high-speed collisions can mean death--instantly, or gradually from broken bones.
Monogamous for life, a pair of Harpy Eagles builds a platform nest out of sticks five feet across high in a tree, sometimes 150 feet from the forest floor. The nest is often lined with green leaves and other foliage, presumably to help keep their chick cool. One to two eggs are laid and incubated for up to two months with the male feeding the female in this time, but except in the most extraordinary circumstances, only the eldest chick survives. The chick requires care for a year or more, thus limiting the parents to producing one chick every two to three years. The juveniles become sexually mature at four years.
Despite the great size of the prey they are capable of taking, Harpy Eagles, like all birds of prey, are limited to carrying no more than half their weight in flight. They will feed on the ground as long as they can, but if challenged for their kill, they will abandon it. As a halfway measure, they will consume as much as they can of their prey until they're able to carry the rest to their nest.
Named by early explorers after the mythical half-woman, half-bird monsters in honor of their size and ferocity, the Harpy Eagle is an endangered species, threatened primarily by habitat loss as large tracts of the rainforest are cleared for farming and ranching. The adult birds have no natural predators, but chicks can be taken from the nest, and with the long reproduction cycle, this proves a serious setback to the birds. Shooting by ranchers is another concern, though the Harpy Eagle far prefers sloths and monkeys as prey; poachers also reduce their numbers, as do illegal parrot trappers who mistakenly view the Harpy Eagle as competition. Ecotourism promotes the protection of the rainforest and its species and is helping the Harpy Eagle; some lodges in its range boast viewing towers to allow visitors to view these magnificent predators. Conservation programs are underway to ensure that future generations will not regard the Harpy Eagle as a memory. |
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| Expand Your Birdy Horizons: Resplendent Quetzal |
[Mar. 14th, 2005|10:20 pm] |
Tonight, after fighting with internet connection and giving up on maintaining a wireless connection for now, I introduce to you Pharomachrus mocinno, the Resplendent Quetzal.
The national bird of Guatemala (and name of their currency), this member of the trogon family is a stunning bird, regarded as one of the most beautiful in the Western Hemisphere. With shimmering feathers of brilliant green, a crimson belly and white undertail feathers, it seems as though it would be hard to miss, but it hides well in the sundappled rainforests of Central America. The red imitates the shadows, while the white blends with pieces of sky, and the green melds with the foliage all around it. The male is especially spectacular, with tailfeathers (actually upper tail coverts) that can reach two feet in length. These tailfeathers were collected from live birds by the Aztecs to use in headdresses for their royalty; the revered bird was released so that it could grow new feathers. Seven hundred quetzal tailfeathers were used in the cloak worn by Montezuma. The male quetzal uses those feathers in courtship displays, swooping in graceful arcs for the benefit of the females. Mayans believed that the quetzal protected their chiefs, and one legend on the source of the quetzal's red feathers claims that they were soaked from the blood of one of their fallen chiefs after holding deathwatch over his body. Perhaps because of the serpentine effect of the long tailfeathers, the quetzal was associated with the feathered serpent deity Quetzalcoatl, a powerful figure found in almost all pantheons of Mesoamerica; the word "quetzal" means "feather" and "coatl" is "serpent."
Quetzals are primarily frugivores, feeding especially on wild avocados; as one of the few birds equipped to handle these large fruits, they are particularly important in the propagation of their favored food. The quetzals themselves are highly dependent on decaying trees to excavate their nests, especially as their beaks are not powerful enough to break tougher wood. They prefer enlarging old woodpecker cavities, but will chip out their own nests if need be. The female lays two light blue eggs, which both parents incubate. The young are fed on insects, amphibians, and small reptiles for a short time, then graduate to fruits. Many predators will take quetzal chicks, and in any given population, only 20% will survive to fledge; toucanets, Brown Jays, squirrels, and weasels all prey on the chicks in the nest. This encourages the young to fledge early and leave the nest sooner to be cared for by their parents outside their nest cavity.
Tied to the avocados, the quetzals live in the ethereal cloud forests, the jungle at high elevations where the avocados thrive in the cooler temperatures. Even as the cloud forests themselves are threatened, the disappearence of the lower forests in turn raises the temperature of the surrounding areas, reducing the potential growing space of the avocado. Ultimately, the quetzal's fate depends on the fate of the cloud forests. |
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| Expand Your Birdy Horizons: Loggerhead Shrike |
[Mar. 13th, 2005|02:30 pm] |
Passerines--the so called "perching birds" or "songbirds"--are a very diverse group, though most seem to fit under certain definitions. Today's bird shatters the preconceptions of songbirds as calm seed and worm eaters of gardens and lawns. Introducing Lanius ludovicianus, the Loggerhead Shrike.
At first glance, the Loggerhead Shrike is a rather unassuming bird about the size of an American Robin, with a bold stripe of black across its eyes and plumage in an uncomplicated pattern of greys, blacks, and whites. In fact, its plumage makes it easily confused with the Northern Mockingbird, though the mocker lacks the strong eyestripe and is a much more slender bird. And the mockingbird does not have a hook on the end of its beak like the Loggerhead Shrike. (Loggerheads are also confused with their relative, the Northern Shrike, which breeds in the Arctic.)
Shrikes don't have a tame diet; in the summer, they feed primarily on grasshoppers and other large insects, snagging them out of the air or pouncing down onto them and stunning them by bashing them into rocks. It then earns its nickname of "butcherbird" by impaling its prey on small thorns, twigs, and barbed-wire fences, thus ensuring that its prey is dead as well as stocking its larder. Insects aren't its only prey, however; when presented with the opportunity, it will hunt snakes, lizards, mice, and even other songbirds. These more challenging prey items are hunted by sneak-attacks and stunning, or by pursuing until its prey tires, and are then swiftly carried to its larder, where it will tear away pieces with its hooked beak.
Loggerhead Shrikes can be found throughought the United States, living year-round in the southern half of the US and summering in the Great Plains and Rockies. They prefer "edge" habitat; trees with prominent perches on the edge of fields. In breeding, pairs weave a nest of twigs and mud in the crotch of a tree, lined with fur, feathers, and grasses. The female lays up to seven brown-speckled eggs, while the male feeds her during the 16 day incubation. Both parents feed the young, which are altricial. They fledge at 16 days and stay with their parents for another 3-4 weeks. Loggerhead shrikes are somewhat monogamous, but females will abandon their mates to raise another brood with another male after her first brood has fledged. Shrikes will often return to nesting sites in prize territory, but otherwise will search for sites elsewhere in the next year.
The fierce habits of this carnivorous songbird make it a very notable species, and one beneficial to farmers for hunting many pest species that otherwise feed on crops; however, it is growing increasingly less common in its range, and is on the verge of being extirpated, or no longer present, in its former Canadian range. Shrikes have many predators, including large corvids like crows and magpies, feral cats, long-tailed weasels, and bull snakes, but these predators can't account for the severe population decline. More likely is habitat loss; former farmland is now being converted to suburbs by urban sprawl, and what shrike habitat remains is often along roads, where they can become victims of collisions with vehicles. Throughout the United States and Canada, programs are underway to study the possible causes of shrike decline and restore habitat by installing perches and larder locations. Shrikes are being banded to track their migration.
This predatory passerine is becoming rarer, but efforts are well underway to try to stop the steep decline and restore their numbers. |
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| Expand Your Birdy Horizons: Lilac-breasted Roller |
[Mar. 12th, 2005|12:43 pm] |
I now introduce a relative of the last spotlighted bird, widespread in African scrub and open woodlands, and the national bird of Botswana; Coracias caudata, the Lilac-breasted Roller.
A bird about 14 inches long with beautiful plumage, the Lilac-breasted Roller is often the first bird that steals safari-goers' attention from big mammals, epecially thanks to its bold fearlessness that allows humans to approach, and its habit of perching conspicuously while watching for insects. It is a member of a group of birds called rollers, so named for the "rolling" motion (a sideways rocking) they perform in their courtship flights. Their main prey is insects and arachnids, but they also feed on lizards, amphibians, and even small birds and rodents. They wait for prey to come close to their perch, then dive down and pounce on it.
Highly territorial, Lilac-breasted Rollers are solitary or paired for most of the year, defending both breeding territories and hunting territories. Some populations are migratory, but others are sedentary, depending on the conditions. Their nests are cavities in termite mounds and old trees, usually old woodpecker and kingfisher nests, but the roller isn't above evicting current residents of what it considers prime real estate. Their aggression is even turned toward much larger and more dangerous creatures; Lilac-breasted Rollers have been seen mobbing eagles and even leopards that come too close to their nests. Females lay 2-4 whitish eggs, and both birds take turns incubating and caring for the young.
Often compared to crows, Lilac-breasted Rollers are relatives of kingfishers and bee-eaters, not corvids or other passerines, but their aggressiveness toward much larger foes and their unmusical "kaaaaarr!" tends to draw comparisons between this colorful African bird and the more monochrome crows.
Tolerant of human activity, Lilac-breasted Rollers nevertheless require wild lands to thrive, and thus are threatened by human encroachment. To a degree, the logging of wooded areas provides the open woodlands they prefer, but the loss of old trees to nest in creates fierce competition between the roller and other species for nesting cavities. These stunning birds draw ecotourists from all over the world to its African home. |
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| Expand Your Birdy Horizons: Belted Kingfisher |
[Mar. 11th, 2005|09:00 pm] |
First of all, I apologize profusely for the lack of updates. Things just seemed to keep getting in the way. These writeups are tougher than they look! I'd like to solicit help in two matters, however. One would be in receiving guest writeups for this spotlight, written in this basic format with image URLs; they can be sent to illucian -at- livejournal -dot- com. The second is...well, being on the Filetmignon cluster means that I lost an earlier version of this writeup when it was in read-only mode and I neglected to copy-paste the entry before submitting. >.> I would be most appreciative of a paid account (and extra icons!!) for this journal that seems to be a minor hit among the birdgeekery of LiveJournal. EDIT: Thank you, anonymous gifter, for the paid account time!! -- There, shameless begging done. Onto the birds!
Today featuring North America's most widespread member of the Coraciiformes, I introduce Ceryle alcyon, the Belted Kingfisher.
A loud rattle is what announces the presence of this skilled fishing bird, often when it's flying from perch to perch. Once it finds a prominent place above water, it watches for the glimmer of a fish below, then dives to seize its prey in its dagger-like beak. The only other kingfishers found in North America are the similarly-colored Ringed Kingfisher, which is larger with a heavier bill, and the much smaller Green Kingfisher; both of these species range only into South Texas in the United States and otherwise move southward into Central and South America.
In a switch from the usual way of things in the bird world, the female Belted Kingfisher is more colorful than the male; he wears a two-tone suit of feathers in blue-grey and white beneath his shaggy crown, while she has the same as well as a rusty breastband.
The Belted Kingfisher can be found almost everywhere in North America, save the furthest northern reaches of Canada and Alaska and the area around Hudson Bay. Its wintering range extends even into northernmost parts of South America. Within its range, it prefers clear, relatively still water, to make it easier to watch for fish. Fish aren't its only prey, however; Belted Kingfishers also hunt frogs, crabs, crayfish, salamanders, mice, and insects, especially dragonflies.
A male kingfisher establishes a territory in the spring, and then courts a female to join him. They are monogamous for a breeding season and may pair up with other birds in the next year. Rather surprisingly, the Belted Kingfisher's "nest" is actually a burrow dug into a clay cliff-face, a nest-type favored by other kingfisher species as well, and it may be some distance from water if no suitable cliff is near their fishing grounds. Both birds work on the tunnel, and the female lays 6-8 white eggs. The male incubates the eggs in the day, trading off with the female at night, with incubation lasting about three weeks. The chicks are altricial and receive care for another three weeks, with feedings tapering off until they are forced to fend for themselves.
The kingfishers themselves are linked to Greek myth, but that's a topic I'll touch on when I feature a more probable species for the basis of that myth.
With their loud rattles and spectacular dives, the Belted Kingfisher is a remarkable bird, very sought-after by birders and bird photographers alike. Though it was once targeted as a predator of fish hatcheries, it has otherwise managed to benefit from human development, especially from sand and gravel pits that provide it with nesting territory. It actually presents benefit to fishermen, thinning out the younger and smaller fish to ease competition for resources. With their sharp beaks that are their hunting tools beneath their shaggy, spikey crests, it's no wonder how they came to have the name kingfisher. |
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| Expand Your Birdy Horizons: Common Nighthawk |
[Mar. 8th, 2005|10:47 pm] |
Introducing Chordeiles minor, the Common Nighthawk.
While it is relatively common in the right locations, it is not a hawk, being more closely related to owls, and it can often be seen in dawn or twilight hours and broad daylight. They can be difficult to spot, thanks to the cryptic plumage of mottled greys and browns that camouflages them at their perches.
The Nighthawk is a member of a family that is now called the nightjars, but an older name is goatsuckers, which is echoed in their family name of Caprimulgiforms. It was once believed that these birds of witches drank the milk from goats, when in actuality they were swooping low to catch insects flying around livestock. Common Nighthawks are very adept at catching insects; one bird had devoured more than 1,000 flying ants in one night. These birds, much more than swallows, provide mosquito control. In capturing insects, they soar over a likely piece of turf and open their very large mouths, which are surprisingly huge in comparison to how their beaks look when closed; it's easy to see how that big gape can make it a snap to catch insects in flight. They have erratic, bat-like flight, and their large eyes help them make use of available light to distinguish prey. Nighthawks are also known to take advantage of lights that attract insects, diving around the lights with beaks gaped. They drink in flight by skimming the water.
Common Nighthawks breed throughout North America into Central America in habitats ranging from sand dunes, forest clearings, grasslands, and urban settings. The male courtship display includes spectacular dives that end in a loud "boom" from the air moving through their primaries, and then a display of their white throat patch while perched near a female. Their normal call is a shrill "peent." (Listen to both the "peent" and the "boom" here.) They're adaptive to the presence of humans, as they make no nest and lay their eggs on flat surfaces; many rooftops provide what they need. They nest on grass, leaves, gravel, and flat stone in more natural settings. The female incubates 1-2 eggs alone, and leaves in early evening to feed. Once the semi-precocial chicks hatch, she feeds them twice after hunting forays in the evening and morning, and the chicks are fledged and able to hunt on their own at the end of a month.
One of the last to arrive in spring and first to leave in autumn, the nighthawk is dependent on the weather that brings clouds of insects, and cannot withstand cold that deprives it of its food source. They migrate in flocks into Central and South America, but little is known of their wintering habitat. Their populations are on the decline, likely from habitat destruction both in breeding grounds and wintering grounds.
A cryptic, mysterious bird, the Common Nighthawk is natural insect control whose shrill calls stir memories of summer twilight. |
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