| 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?v=91.6) 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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