20-Apr-23, 08:07:42 AM
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Other Nature Related Information / General Nature Discussion / Patterns from eBird –Cedar Waxwing Migration patterns remain poorly understood
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on: 10-Mar-10, 06:35:55 AM
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March 8, 2010 Patterns from eBird – Cedar Waxwing
The Cedar Waxwing is an abundant and easily recognized bird across much of North America, yet its migration patterns remain poorly understood. This is because across much of the country Cedar Waxwings are present year-round, making influxes of migrants hard to discern. eBird now provides a unique information resource for identifying patterns of species occurrence, since it draws upon a network of tens of thousands of contributors who collect observations throughout the year. Our "Patterns from eBird" feature will highlight and discuss some of the interesting and enlightening natural patterns that can be uncovered using eBird's "View and Explore Data" tools.
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23267
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Other Nature Related Information / General Nature Discussion / Calif condor couple lays egg at Pinnacles park
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on: 10-Mar-10, 06:28:02 AM
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FRESNO, Calif. - Biologists at Pinnacles National Monument are celebrating the first condor egg laid by a mating pair inside the park boundaries in more than a century.
The egg marks the latest encouraging development in the slow recovery of the endangered flying giants in the regions they historically inhabited. The effort has been hampered by hunters and lead poisoning of the birds.
A female released in 2004 in the Central California park and a male released the same year 30 miles west at Big Sur had been observed engaged in courtship behavior earlier this year, park spokesman Carl Brenner said.
"They are now the proud parents of a small egg," Brenner said.
Biologists confirmed the presence of the egg after hiking to the site on Friday.
In 1982, the last 22 California condors were placed in a captive breeding program. Today, there are 348 in the world, with about 180 flying free at three locations in California and at the Grand Canyon in Arizona. Another dozen are in Baja California.
The goal is to have 450 birds in three distinct populations, with 15 breeding pairs in each group.
"We had a good year last year in Southern California, but it's not universal because we had a number die of lead poisoning in the Pinnacles area and Central Coast," said Michael Woodbridge, a spokesman for the U.S. Fish and Wildlife Service Condor Recovery Program.
One of the dead birds was the mother of a male chick that eventually learned to fly in the wild last April on a ranch outside of Pinnacles National Monument. The chick survived and lives with its father.
Some birds suffer lead poisoning after eating gut piles left by hunters, despite a ban on lead bullets in condor country.
Of the 77 eggs laid in the wild since 2001, 33 lived for at least six months — long enough to fly — with the success rate increasing every year, Woodbridge said.
"That's close to 50 percent, which is probably on par for any species in the wild," Woodbridge said.
Condors, with 10-foot wingspans, generally mate for life. By coincidence the Pinnacles pair with the egg are numerically sequenced — female 317 and male 318 in the population being tracked. It was the first mating attempt by both.
The female was part of the second of six groups of condors released since 2003 at Pinnacles, part of the birds' historic range. The park was attractive to biologists involved in the recovery effort because of the numerous potential nesting sites along craggy cliffs, including the cave being used by Nos. 317 and 318.
It's a two-mile hike over a gain of nearly 1,200 feet in elevation to a viewing site, but the birds "have given us a comfortable place to sit and watch," Brenner said. The viewing area is located across from a bench offering expansive views of the park.
Pinnacles biologists have swapped out the new egg for a wooden one, Fifty-seven days from now — or shortly before the egg is due to hatch — they will replace it with a viable egg produced by condors in captivity.
The swap is standard procedure for most of the Central Coast birds, which sometimes feed on dead sea lions and other pinnepeds that wash up along the Big Sur coast. Those animals, however, often harbor PCBs and the DDT derivative DDE in their blubber. Birds that ingest the chemicals can produce eggs with thin shells.
The real egg produced at Pinnacles will be hatched in a zoo, Brenner said, ensuring an offspring for the pair of condors.
"They are first-time parents, and we don't want them to get discouraged," he said.
Visitors with spotting scopes can see the nesting site from Scout Peak bench on the popular High Peaks Trail.
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Other Nature Related Information / Raptor Web Cams / Eaglet named (NOAH)
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on: 09-Mar-10, 08:48:38 AM
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CHARLOTTE, N.C. -- More than 4,300 votes were cast in our Name the Newborn contest and Noah is the name of Savannah's eaglet with 52 percent of the vote. It was named for Lance Corporal Noah M. Pier who died last month while serving overseas in Afghanistan. In a few weeks Noah the eaglet will be taken to a hack tower to learn how to survive in the wild. The process of "hacking" involves introducing the eaglet to the wild. The eaglet will be placed in the tower and fed daily. It is hoped that the eagle will eventually fly from the tower and hunt its own food. A well-deserved name!
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23273
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Other Nature Related Information / General Nature Discussion / Redhead's migratory stop warms the heart of any birder (MD)
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on: 09-Mar-10, 07:12:35 AM
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Snow swirled about us and punishing winds blew off the frigid Choptank River. Peering through frosted air, we could see scores of ducks huddled close to shore. It was a mixed flock of familiar winter visitors to the tidal rivers of Maryland's Eastern Shore.
A handful of mallards, black ducks and a couple dozen American wigeons were scattered in small clumps among the 150 or so canvasbacks. Farther out, ghostly scoters and buffleheads, partially obscured by the steady snowfall, were rolling in and out of sight in the wind-whipped waters.
A fresh blast of near-gale force wind made it clear-the good birding was about to be trumped by the wretched weather.
Before we turned back to the warmth of the car, I took a final, closer look at the nearby flock. Canvasbacks are perhaps the most beautiful birds in the world, with an elegant shape and arresting color scheme. They were certainly worth another look. That's when I spotted a single duck with a bright yellow eye, gray back and eponymous red head. A male redhead (Aythya americana) was not more than 10 yards away, bobbing among the other birds, taking advantage of the relative shelter of this shallow cove.
Redheads are handsome waterfowl in their own right. The male's color pattern mimics that of the canvasback, but the redhead works with a slightly different palette. He has a high arched back of gray and a black chest. His neck and puffy, round head are a deep brick red. A black-tipped, blue bill and amber eye complete the portrait.
In flight, the redhead shows a white belly and light gray under-wings.
Like most ducks, the female wears a commonplace brown plumage. Even the hen's blue-gray bill is a forgettable muted version of the male's memorable one.
The redhead is a mid-size duck, stretching about 19 inches from tail to bill.
Redheads breed in the Great Northern Plains of the United States and up into the Prairie Provinces of western Canada and central Alaska.
The birds build a floating, vegetated nest on a freshwater lake or pond. The first step out of the nest for these ducklings will be into water.
Females lay about 10 eggs in a clutch. But it might not be in her own nest. Redheads are prolific mooches. Know to scientists as "brood parasites," redheads often lay their eggs in other ducks' nests.
The involuntary foster parent, which may not even be another redhead, will provide the incubation and early care.
Nests can contain dozens of eggs from several hens. One case reported 80 eggs in a single nest. The chances of chicks surviving with such extraordinary clutch size are poor. The large number of initial eggs helps to counter the high nest-mortality rates.
Redhead populations are declining, the result of habitat loss and competition for its selective diet.
Fortunately, the bird is fairly numerous in many of its traditional habitats and is classified as a species of "least concern" for conservation purposes.
After they breed, redheads migrate to warmer climes for the winter. They spread out along the Atlantic Coast, the Great Lakes, the Ohio-Mississippi river valleys, and all across the southern United States. The largest winter populations are found in the Gulf of Mexico.
The lone redhead here on the Choptank may have started his life on one of the prairie potholes of Montana or Manitoba. Next winter, he may switch from the Atlantic Flyway with a Chesapeake destination to the Mississippi Flyway to spend a few months in Mexican waters.
Redheads are diving ducks, surviving on a diet of underwater vegetation. They are partial to eelgrass in the Chesapeake. This underwater Bay grass was once abundant, but pollution has taken a heavy toll. Recently, the gradual rise of water temperatures associated with climate change has made the Chesapeake's waters too warm for this species to thrive. In August 2005, the defoliation of eelgrass in the Bay was associated with record warm water temperatures.
Like worldwide temperature trends, the declining prevalence of redheads in the Chesapeake tells an unmistakable story of climate change. These long-term data are immune to the vagaries of an especially tough winter on the East Coast or the overheated rhetoric of some science deniers.
The bitter wind and stinging snow finally prevailed, and I walked woodenly on frozen legs back to the car. The redhead had done his job. With his handsome shape and colors, he took me away from a bureaucrat's artificial world and let me focus on the reality of this frozen scene of peaceful beauty. And that was enough to warm my heart, no matter what the thermometer said.
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Other Nature Related Information / General Nature Discussion / Exhibit has condor killed by antifreeze
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on: 09-Mar-10, 07:05:06 AM
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CAMARILLO — A condor that died after being exposed to antifreeze will be on display at CSU Channel Islands this year.
The condor, named Chocuyens, was the first bred in captivity to be released into the wild through the California Condor Recovery Program. It will be on display at the John Spoor Broome Library, from Thursday to next February.
The Camarillo university will have a celebration at 1:30 p.m. Thursday to open the Condor Chocuyens Exhibit. Speakers will include CSUCI President Richard Rush; Amy Denton, chairwoman of the biology department, and Jesse Grantham, condor coordinator for the California Condor Recovery Program, among others.
The event is open to the public. The condor is on loan from the U.S. Fish and Wildlife Service. About 40 condors, which are an endangered species, live in this area, most of them in the Los Padres National Forest.
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Other Nature Related Information / General Nature Discussion / Mirrored Towers Fatal Attraction for birds (Toronto Canada)
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on: 09-Mar-10, 07:02:07 AM
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Shanta Persaud was standing at the photocopier one morning when she saw a little bird fly directly into a large window on the ground floor of her Scarborough office building. The receptionist ran outside to find the bird on the ground, gasping for its last breath.
It “just hit the glass and fell to the ground. It sounded like a pebble against the glass,” she said. “It’s so sad.” And it wasn’t the first time she’d seen this happen.
For birds migrating through Toronto each spring and fall, the three multi-storey office buildings at 100, 200 and 300 Consilium Place are a death-trap. So much so that last week, the environmental groups Ontario Nature and Ecojustice — formerly the Sierra Legal Defence Fund — initiated a private prosecution against the buildings’ managers under the Environmental Protection Act and the Ontario Society for the Prevention of Cruelty to Animal Act.
The buildings, near Highway 401 and McCowan Rd. are covered in mirrored glass and as high as 17 storeys. They stand out in an area with few highrises, making them even more lethal than buildings downtown.
In 2008-2009, more than 800 birds were recovered from the lawns around the buildings, ironic considering that the Building Owners and Managers Association had awarded the complex its “Go Green certificate of achievement” for its environmental practices.
Over the past decade, more than 7,000 birds of 82 species have met harsh, painful deaths after flying into what bird safety advocate Michael Mesure calls “the most reflective glass windows of any building in the city.”
The action against management company Menkes alleges that the building’s reflectivity has caused death and injury to birds, including species in decline, and, with respect to animal cruelty legislation, has put animals in distress.
“If you see these buildings, these are essentially mirrors,” said Ecojustice lawyer, Albert Koehl. “What the birds see is the sky and trees reflected in the windows, and they fly right into them.”
Most daytime collisions actually happen between ground level and the fourth floor.
“Most of these birds die of traumatic injuries such as fractured skulls or broken backs,” Koehl said. The broader issue, he adds, is the decline in migratory birds observed year after year.
The high incidence of bird deaths caused by hitting buildings has been a significant concern for years. The non-profit group Fatal Light Awareness Program has tracked bird deaths in Toronto for more than a decade and initiated campaigns such as Lights Out Toronto to encourage building managers to turn lights off at night. (Nighttime lights confuse and attract birds into office windows.)
But this is the first time the law has been invoked in an attempt to change business behavior. Caroline Schultz, executive director of Ontario Nature, says most companies have refused to take any real action.
“There has been nothing specific in terms of legal action to really force business owners to seriously review the options that are available to them to reduce the problem,” said Schultz. “That’s the reason for doing this private prosecution, because this is the worst building in Toronto in terms of bird deaths every year.
“Opportunities exist to do things to mitigate the problem, and what we really want to do is to set a precedent that business owners have a responsibility under the law to do this,” she said. “It’s not voluntary.”
Menkes is to appear in the Ontario Court of Justice on March 17. The maximum fine under the EPA is $6 million per day for the first offence.
The building owner didn’t respond to numerous calls for comment on the charges or efforts to address the problem.
Toronto is on the migratory path for millions of birds, said Mesure, FLAP’s executive director. The spring migratory period begins next week and will go until the beginning of June. The fall migration runs from August to the end of October.
Mesure has worked on the issue for 20 years, but vividly recalls two “days of hell” at the Consilium towers when it seemed to be “raining birds.” On May 12, 2001, he said, FLAP volunteers recovered more than 500 injured or dead birds in six hours. On a Thanksgiving weekend in 2005, the group picked up 400 birds over two days.
In the past few years, the building managers have made attempts to address the problem. According to Persaud, employees have been told to report falling birds and to turn the lights off and put down blinds at night. They have also tried tactics to scare the birds away, such as hanging large orange balls from surrounding trees, and placing silhouettes of hawks and owls inside the windows.
But Mesure says Menkes has been reluctant to do anything more because the only real solution involves changing the aesthetics of the building.
“The only solution is to create patterns on the outside of the glass, so that the bird interprets the glass as a solid object,” he said. “The argument has always been that (owners) don’t want to change to look of the building.”
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Other Nature Related Information / General Nature Discussion / Chesapeake's ospreys mark return of spring
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on: 09-Mar-10, 06:46:34 AM
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The warmer temperatures have brought with them a familiar Chesapeake icon. Ospreys (Pandion haliaetus) occur in nearly every corner of the globe, but nowhere as abundantly as on the Chesapeake Bay.
Ospreys return to the Chesapeake every spring from southern wintering grounds. Their abundance in the Bay region is due to the availability of food: They feed exclusively on live fish.
Their curved, sharp talons and rough-soled feet are designed to hold on to slippery fish.
Large brown and white birds of prey, they're about 2 feet long with wing spans of 4-5 feet. When in flight, their long, narrow wings take on the shape of an outstretched M.
Ospreys hunt by soaring over water, periodically hovering on beating wings to scan the surface for schooling or spawning fish. Upon sight of its prey, the osprey makes a spectacular dive. Folding its wings tightly, it descends swiftly and plunges feet first into the water, often submerging itself completely. Another technique is a shallow scoop for fish at the water's surface.
In addition to food, the Chesapeake provides many favorable nesting areas over the water such as duck blinds, navigation markers or man-made nesting platforms. Offshore structures offer protection from predators like raccoons, and rapid detection and escape from danger. On land, ospreys may nest on high trees and utility poles.
Ospreys 3 years or older usually mate for life, and will use the same nest site year after year A recently reunited pair will begin the task of nest building or repair.
Younger birds must first attract and court a mate. During courtship, the male will feed the female and it is believed that this may actually strengthen the pair's bond to one another. Spring courtship marks the beginning of a five-month period when the pair works together to build a nest and raise their young.
A clutch of three or four eggs is laid by the third week of April. The sheer bulk of the nest and a depressed center conserves heat. The eggs, usually mottled cinnamon brown, are about the size of jumbo chicken eggs, and must be incubated for nearly five weeks.
Finally, the eggs yield their treasures: helpless chicks, weighing 2 ounces or less, that can barely beg for food. Amazingly, with plenty of fish, these balls of fluff will become soaring acrobats in just eight weeks.
By late July, most young Chesapeake ospreys are on the wing. By the end of August, both young and adults begin their southern migration to wintering grounds in the Caribbean, Central America and South America.
Ospreys, swooping and plunging for fish, have always been a familiar site for residents and workers on the Bay. But there was a time, not long ago, when the osprey's survival on the Chesapeake was threatened.
For years, ospreys and many other birds of prey were unable to produce enough young to maintain their populations. Production decreased because of egg failures caused by extremely thin and easily broken eggshells.
Years of research led to the discovery that a pesticide, known as DDT, caused eggshell thinning in many birds. Since World War II, DDT was sprayed to control mosquitoes and crop pests. The use of DDT was banned in the United States in the early 1970s. Osprey and other birds of prey have since made remarkable recoveries.
Despite the hardships, ospreys have continued to flourish around the Bay. Their spectacular flights and insistent calls can be heard throughout the spring and summer. The resurgence of ospreys after the ban of DDT is a success story. But a new threat has come to light.
The Chesapeake Bay has some of the finest fishing on the East Coast. The fishing season corresponds with the breeding season for osprey.
Ospreys are very tolerant of humans and will fish and nest close to populated communities. They often line their nests with a variety of natural and man-made materials. Some of the man-made materials ospreys pick up include paper, plastic rope and fishing line.
Osprey chicks have been found entangled in fishing line or impaled with fishing hooks. Adults have also been spotted entangled in line. Legs, wings and beaks can become so tangled that the birds are not able stand, fly or eat. Conservative estimates indicate that fishing line is present in 5-10 percent of all osprey nests on the Chesapeake Bay and surrounding rivers.
Anglers can reduce the injuries or deaths to osprey and other wildlife simply by discarding their fishing line and hooks. If possible, retrieve broken lines, lures and hooks. Always deposit them in trash containers or take them home. Help protect Chesapeake Bay wildlife.
The resurgence of ospreys after the DDT ban is a success story. This success can extend to the entire Bay and other wildlife as we continue to protect and restore habitats. Each of us can help by disposing fishing line, hooks and other potentially harmful objects into trash cans.
By doing things, we help to ensure that the osprey remains a familiar site on Chesapeake Bay.
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Other Nature Related Information / Falcon Web Cams / Oh boy, another falcon cam (Wilmington DE)
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on: 08-Mar-10, 11:20:20 PM
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It's Live streaming but I guess not at night. Curious to see this in the daylight. http://www.dosbirds.org/wilmfalconsPositive signs for Delaware birdsDesktop birdwatching in Delaware is now available via the Internet. A webcam is now streaming video of a peregrine falcon nest on the 19th floor of the Brandywine Building in downtown Wilmington. The ledge is very similar to the bird's natural habitat, cliffs. "High rises, like in Wilmington and Philadelphia, they can serve as almost like a pseudonym for cliffs," says Delaware wildlife biologist Anthony Gonzon. The webcam is funded by the Delmarva Ornithological Society and the DuPont Clear Into the Future program. The state's falcon population has remained steady over the past few years. Gonzon says there are three to five pairs of the birds living in Delaware. The ones on the Brandywine Building have been there for about 10 years. "In certain years, we've had them on the Delaware Memorial Bridge and also on the Summit Bridge. They use those surfaces underneath the bridge almost as a cliff face as well," Gonzon says. Falcons aren't the only birds of prey that are ready for their closeup. Bald eagles are being seen more frequently in Delaware as well. The Delaware Department of Natural Resources and Environmental Control counted 120 bald eagles during its mid-winter survey, 77 adults and 23 younger birds. Gonzon says the Chesapeake Bay watershed, which includes Delaware, "has seen a real, true resurgence in eagles in the last 10 to 15 years. These birds need adequate habitat to forage over winter here within the region, and it looks like Delaware is a place they seem to be choosing." Bald eagles were officially removed from the endangered species list by the federal government in 2007. Gonzon says the increasing number of eagles in Delaware, coupled with a steady population of falcons, is definitely a positive sign. "They're top of the food chain type birds. They rely on a lot of different things in order to persist and survive in Delaware," says Gonzon. "There are enough resources here for them to use, and it's allowing them to continue to be successful, and we only have high hopes for the future." Gonzon says if anyone spots a bald eagle in Delaware, the Division of Fish and Wildlife wants to hear about it. "Even the smallest observation can help us locate new eagle nest sites, so even as small as seeing an eagle fly across the road, accumulation of those types of observations can help us pinpoint places where we think eagles may have set up a nesting territory," he says.
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