Thursday, October 05, 2006
DC Audubon is co-hosting a talk on birds in the DC area. Peter Vankevich, DC Audubon member and author of a monthly DC birding column in the Hill Rag, and others will discuss what birds you may see in DC and tips on how to identify them. Reception to follow.
417 East Capitol St., SE
Oct. 19 @ 7 PM
Tuesday, September 12, 2006
Friday, September 08, 2006
Next Sunday, Sept. 17, join DC Audubon's annual field trip to Rock Creek Park in search of Fall migrants. We'll be looking for those confusing Fall warblers, of course, but not neglecting any others. Meet by the Rock Creek Nature Center at 7 A.M. (5200 Glover Rd., N.W., about 1/4 mile south of the intersection of Glover and Military Roads). The Ridge and Maintenance Yard areas will get most of our attention, but we may visit others (within walking distance from the Center) at the leader's discretion. We should finish up by 11. Besides the trusty binocs & field guide, I recommend insect repellant, sunscreen, and waterproof footwear (not a bad idea to bring water & snacks as well).
Please RSVP to the leader, Paul DeAnna by telephone in the evenings after 6pm (202) 544-2680. Please include a phone number where you can be reached the evening before the trip, just in case a weather postponement becomes necessary. If you can offer a ride to a non-driving birder in your neighborhood, please let me know the general area you're coming from. I'll do what I can to put those offering rides in touch with those needing them. Detailed driving directions are available on the Park's website.
Rock Creek is also accessible by public transportation. Take the E2 bus to the intersection of Miltary Road and Glover Road (a.k.a. Oregon Ave), NW. From there follow the path at the southeast corner of the intersection to the Nature Center.
An announcement of this field trip is also posted on our website.
Thursday, September 07, 2006
Here is how it works: Keep your eyes to the skies at dusk in late July and watch for areas where swifts are feeding. Look for a tall shaft, chimney or similar structure to locate where Chimney Swifts (central to east coast) or Vaux's Swift (Pacific coast) go to roost in your area.See here for contact information and results from previous years.
This year, on one night over the weekend of August 11, 12, 13, and / or September 8, 9, 10 observe the roost starting about 30 minutes before dusk and estimate the number of swifts that enter. When you have your number, contact us with your results. That's all there is to it!
Please include the following information:
- Number of swifts counted
- Time (and time zone)
- Address: city, state/province
- Broad description of the site, e.g. school, warehouse, residence, Chimney Swift Tower, etc.
- Weather conditions may also be reported.
Chimney swifts became common in urban areas because of the availability of chimneys and other vertical structures for nesting. However, in recent years the population has declined as chimney construction has changed to discourage nesting. Swifts benefit city residents by consuming large number of insects every day. For more information on chimney swifts, see ChimneySwifts.org.
Wednesday, August 30, 2006
The Sun article provides two possible explanations from local wildlife experts. One focused on a possible injury.
"Why the heck it would stand around on Bolton Street for an hour? Who knows?" said Glenn Therres, associate director of the Wildlife and Heritage Service at the Maryland Department of Natural Resources. "I don't know if it flew into something and was dazed for a while. It could have been injured, but the fact that it flew away suggests the injury might not have been that severe."A second explanation is that it was merely resting.
At any given time, there are about 2,000 bald eagles in Maryland, Therres said. The eagles nest along the shores of tidal waters in the region, but the birds - which were upgraded to threatened from endangered in recent years - rarely if ever hang out on city sidewalks, Therres said.
"There are a lot of them floating around, acting like teenagers and juveniles, just kind of looking for a good place to eat or to socialize with other birds their own age," Therres said. "A wooded shoreline on the Potomac or Susquehanna [rivers], but not normally in an urban neighborhood in Baltimore City."
David Curson, director of bird conservation for the Maryland and District of Columbia branch of the National Audubon Society, said the bird might have eaten a large catch of fish and was too stuffed and lazy to move.
"It's difficult to explain, but one possibility is, it may have eaten a large meal," Curson said. "Sometimes, when a bird like that eats a large meal like that it gets weighed down. But without knowing all the facts and not having seen the bird myself, it's difficult to be sure."
Monday, August 28, 2006
The refuges damaged along the coast are important for both breeding and migratory birds. Twelve Important Bird Areas lay in the direct path of the storm. The long-term effects of the storm on the birds that used those areas will not be known until more research is done. In the short term, many birds seem to have abandoned their traditional nesting habitats. Among the species with reduced nesting colonies include Brown Pelicans, several species of herons, Black Skimmers, and Sandhill Cranes.
On a lighter note, Judith Toups reports that in the weeks after Hurricane Katrina, her yard was filled with ruby-throated hummingbirds.
Monday, August 21, 2006
Sunday, August 20, 2006
The new regulatory program consists of three components. The first creates control and depredation orders for airports, landowners, agricultural producers and public health officials that are designed to address resident Canada goose depredation and damage while managing conflict. This component will allow take of resident Canada geese without a federal permit provided certain reporting and monitoring requirements are fulfilled.
The second component consists of expanded hunting methods and opportunities and is designed to increase the sport harvest of resident Canada geese. Under this component, States could choose to expand shooting hours and allow hunters the use of electronic calls and unplugged shotguns during a portion of early September resident Canada goose seasons.
The third component consists of a new regulation authorizing the Director to implement a resident Canada goose population control program, or "management take". Management take is defined as a special management action that is needed to reduce certain wildlife populations when traditional and otherwise authorized management measures are unsuccessful, not feasible, or not applicable in preventing injury to property, agricultural crops, public health, and other interests. Under Management Take, the take of resident Canada geese outside the existing sport hunting seasons (September 1 to March 10) would be authorized and would enable States to authorize a harvest of resident Canada geese between August 1 and August 31. Management take would be available to States in the Atlantic, Mississippi, and Central Flyways following the first full operational year of the other new regulations.
In the DC area, there are between 500 and 600 resident geese living in the Anacostia watershed.
ARLINGTON, Va. A regional fisheries commission has agreed to cap the commercial catch of menhaden in the Chesapeake Bay.That cap is intended to give scientists time to assess the health of the tiny but important bait fish.
Meeting in Arlington, the Atlantic States Marine Fisheries Commission voted today to set the cap through 2010....
The annual catch will be limited to 109-thousand-20 metric tons, with flexibility for years when the catch is up or down.
Tuesday, August 15, 2006
A research assistant at the American Museum of Natural History, Mr. Bull led popular birding tours of Long Island and Central Park in the 1960’s and 70’s and meticulously kept track of the species and the state of their habitat.
In 1964, he wrote a book, “Birds of the New York Area,” intended for would-be birders living in the suburbs of New Jersey, Long Island and Connecticut and for those in Manhattan itself, a prime birding destination. It covered the mourning doves of Central Park to the horned grebes off Montauk Point.
Mr. Bull later expanded his reach and wrote about all of the 410 bird species that had been recorded throughout New York State. That book, “Birds of New York State,” which was published in 1974, was the first exhaustive survey of the subject in 60 years. Another researcher, E.H. Eaton, had recorded only 366 bird species in 1914.
In Mr. Bull’s book, he noted the new or increased counts of species usually found at more southerly latitudes — like the snowy egret — and suggested that a milder climate might be at work in changing migration patterns.
Joel L. Cracraft, curator in charge of the ornithology department at the American Museum of Natural History, said the guidebook was “a first-rate state bird book.”
“At the time,” Dr. Cracraft said, “there was not a high-quality and professional account of the great diversity of New York’s species and their distributions.”
Menhaden filter the bay's waters by eating the microscopic plants and animals that consume dissolved oxygen needed by other aquatic life. In turn, they're a primary food source for sport fish, such as striped bass, bluefish and weakfish, and seabirds, including loons, gulls and gannets.
Ongoing scientific research focuses mostly on the ecological role that menhaden fill underwater. Broader public awareness has centered on the fish's importance to recreational anglers. But, like striped bass, ospreys favor meals of menhaden over other fish.
"Of everything we know about the bay, this is one of the fundamental food chains: Ospreys eat menhaden," said Paul Spitzer, a Maryland ecologist who specializes in birds.
One study found that menhaden made up 70 percent of the diet of ospreys nesting on Mobjack Bay off the coasts of Gloucester and Mathews counties.
Other studies done along the Atlantic coast have turned up similar results.
Menhaden swim in large schools that skim the water's surface, and they move straight ahead rather than dart around like other fish.
That makes them a perfect prey for circling ospreys, as well as Omega Protein's spotter planes, which radio a school's coordinates to waiting boats.
A fishery commission is considering imposing limits on harvesting of Menhaden while more research is done to determine the causes of the fish's decline.
Sunday, August 13, 2006
Four Audubon members set out from Washington on August 12 to look for late summer birds. The day was perfect for birding: high around 80, clear, and breezy. We set our sights on Bombay Hook National Wildlife Refuge. This refuge, which sits at the edge of Delaware Bay, consists of close to 16,000 acres of tidal salt marsh, together with several freshwater impoundments and upland hardwood forest. The diversity of habitats makes it possible to find many species of birds, especially during migration. Bombay Hook is a fine place to bird in any season, but is at its best during spring and fall migration. For a Washington-based birder, the attraction of this refuge is the ability to see many species of shorebirds that are hard to find at inland locations.
Wednesday, August 09, 2006
For a more recent account of Bombay Hook by a local birder, see here.
For directions and RSVP information, see our webpage. (It is important that you contact the trip leader as soon as possible if you intend to come.)
Between January and March 2005, 33 birds at two breeding colonies in New Zealand were fitted with tags weighing 6g, allowing researchers to track their journey.One interesting result of the study is that individual birds do not travel around the circumference of the Pacific, as previously thought. Instead they travel quickly to one of the winter feeding grounds, located near California, Alaska, and Japan, and then return quickly to their breeding grounds at the end of the southern winter. Below is a map showing the travels of the 19 shearwaters with working tags.
In the autumn of that year, 20 of the tags were recovered when the birds returned to their burrows at the breeding grounds; 19 of the devices had successfully recorded the bird's movements.
Data showed that some birds travelled up to 910km (565 miles) in a day, and dived to depths of 68m in their search for food.
Blue = Breeding season activity
Yellow = Flight north
Orange = Wintering activity and flight south
Saturday, August 05, 2006
(From NPR) For decades now, ecologists have been attaching radio transmitters to the bodies of large animals: whales, bears, elephants, condors and eagles for starters. What these scientists haven't done is stick the same devices onto animals like song birds and big insects, those migratory flying things that sometimes mow down crops and spread diseases.
For eight years now, Wikelski's been the leader of a group of scientists who do collect those data points, with the help of radio transmitters no bigger than a baby's thumbnail. These scientists are known as "microtrackers" and for now they're few and far between.
But Wikelski's work is changing that by forcing ornithologists to change the way they think about migration. His first microtracking studies started nearly a decade ago when Wikelski captured groups of mid-Western thrush and glued extremely sophisticated radio transmitters to the bellies of these birds.
"The transmitters recorded heartbeat, breathing, wing beats and location," he said. "Once every second, they sent all this information out in concentrated bursts."
Wikelski says we know very little about how small animals migrate. Scientists would find out where birds are born and where they die. They would discover where birds are making pit stops on their trips home. And they would be able to track locust swarms and birds that could carry avian flu across international boundaries.
Wikelski turned the focus of his research to flying insects. With the help of prominent entomologists like Mike May of Rutgers University, he's been attaching even smaller transmitters to the backs and bellies of insects. Listen and read more on NPR.
Tuesday, August 01, 2006
URGENT - We have 24 Hours to Stop the Most Deadly Pesticide to Birds
The U.S. Environmental Protection Agency (EPA) is poised to make a decision on whether to ban the bird-killing pesticide, carbofuran. This is the most deadly pesticide to birds currently being used in the United States. It is more toxic than DDT. A single drop is enough to kill a bird.
We have just learned that because of pressure from the manufacturer, FMC corporation, the EPA may make the wrong decision and elect to keep this pesticide on the market. We have 24 hours to counteract the industry pressure. We need your help.
We ask you to email firstname.lastname@example.org, CCing email@example.com telling the EPA to ban carbofuran now because of its danger to birds, other wildlife, and people. Your email can be brief. Use the talking points provided below to help. What is important is that you tell them in your own words that you do not want carbofuran to be used in the United States. Alternatives exist that are equally effective and not deadly to birds. There is no reason to keep carbofuran registered.
Please send your email before 5pm Wednesday August 2, 2006!
Alternatively you can fax your comments to 202-564-0512.
Thank you for taking this emergency action on behalf of birds and wildlife,
President, American Bird Conservancy
We provide the following talking points to help you let EPA know why this chemical must be banned:
- All legal uses of carbofuran kill birds resulting in potential violations of the Migratory Bird Treaty Act (MBTA) every time it is applied. Farmers are placed in jeopardy of violating the MBTA whenever carbofuran is used, even if
they follow the label directions.
- Carbofuran is very toxic to people. Human risk assessments have been done three times and they show greater risks to farm workers each time they are refined. These studies indicate that carbofuran is too dangerous to use.
- Carbofuran is so toxic it kills all the beneficial insects as well as pests with the result that integrated pest management cannot be done.
- Carbofuran is so toxic that no crop rotation can be performed for ten months after application. This eliminates the possibility of crop rotation as a tool for reducing insect damage to crops.
- Alternative chemicals exist for all crops except artichokes. Many alternatives exist for corn. Only a very small percentage of corn produced in the U.S. uses carbofuran now because of its environmental effects and safety issues.
- New insecticides have been developed for rice, cotton, corn, and other crops specifically to replace carbofuran. Most of these are reduced risk chemicals presenting much less bird, wildlife, and human health risks.
- Transgenic corn has been developed specifically for resistance to corn rootworm and European corn borer, further reducing the need for conventional pesticides.
- The United States is a world leader in pesticide regulation. Cancellation of carbofuran will send a strong message to Latin America, Canada, and Mexico about the dangers of this pesticide. This will help save birds in those countries when they phase out carbofuran. Canceling the tolerances of pesticide residues on foods will immediately limit the use of carbofuran in all countries that export to the US.
- Provide sources of water for drinking and bathing. Remember that smaller birds prefer shallow water. Some ideas for providing water are here. Empty and refresh the water to keep it clean and free of mosquito larvae.
- Clean hummingbird feeders and refresh their sugar water regularly. Very warm conditions can lead to the growth of dangerous bacteria and fungi.
- Keep any seed feeders clean of refuse where germs could breed and spread.
Remember to keep yourself safe by following the CDC's heat illness guidelines.
Monday, July 31, 2006
The Washington Post Features the The Washington Biologists' Field Club which is celebrating 100 years of self-professed geekdom (six years late) this year, with a 150-page volume summarizing a century of counting every living thing on Plummers Island, the club's buggy, overgrown paradise a few steps into the Potomac, just downriver from the American Legion Bridge.
Established in 1901 as a weekend retreat, Plummers Island, called by the field club "the most thoroughly studied island in North America," today represents one of the most comprehensive, longest-running biological inventories in the country.
Scrambling over Plummers Island's rock and scrub, club members have documented every living thing known to have existed there. To date, that includes 885 species of vascular plants, 70 mosses and 597 beetles -- not to be confused with the five different cockroaches they have found
The stories begin in 1899, when botanist Charles Pollard formed the Washington Biologists' Field Club, and began the search for a suitable field camp.
In 1901, the group leased Plummers Island, which it bought seven years later. For about $200, the members built at its rocky pinnacle a wooden cabin with few amenities beyond a big fieldstone fireplace and lean-to kitchen.
At the time, the island was a mix of untended farmland, forest, rock and shoreline. The blend drew plenty of creatures and plant life, and the members began collecting, each in his area of expertise.
For about three decades, Shetler has collected plants on the island. Opening a steel cabinet down the hall from his Smithsonian office, he flipped through yellowed folders. Inside rested mistflower specimens collected as early as 1917, the vivid blue blossoms on some still colorful.
*Washington Biologists' Field Club Website
Friday, July 28, 2006
The presence of mercury in lakes and streams is already well documented, and the New York Department of Health advises people to restrict the consumption of any freshwater fish caught in most of the state to no more than one meal a week.
But Dr. Evers is one of the first scientists to test for wildlife mercury contamination beyond fish. He began his work in this area in 1998 and found that common loons, which eat fish, had highly elevated levels of mercury that made them lethargic and caused their reproductive rates to drop.He then decided to study songbirds, which never eat fish. In particular, he wanted to study the wood thrush, a small bird with a distinctive song that was once common throughout the Northeast. The population of wood thrushes has declined 45 percent in recent decades.
It was once thought that destruction of the bird’s forest habitat was responsible for the decline. But Dr. Evers now suspects that mercury contamination might be a factor, along with the wide-ranging negative effects of acid rain on the forests....
Dr. Evers’s work suggests that when mercury falls on land, it is absorbed by soil and by fallen leaves that are consumed by worms and insects. Songbirds then feed on the bugs, absorbing the mercury.
While all the birds he tested last year had mercury in their blood, wood thrushes had the most, Dr. Evers said, an average of 0.1 parts per million. That is below the federal safe standard for fish (0.3 p.p.m.) but high enough to affect the birds’ reproductive cycle.
With fewer songbirds to eat potentially harmful insects, the state’s forests would be at greater risk for damage by gypsy moths and other pests, Dr. Evers said.
Beyond that, mercury leaching into soil could find its way into the food chain in ways that are still unknown, he said.
Friday, July 21, 2006
Ruddy Turnstone / Photo by Peter VankevichIf you missed DC Audubon's May field trip to Bombay Hook, you have another shot to watch shorebird migration with us. Watch our webpage for details on our upcoming field trip to the Delaware Marshes.
This photograph was taken by Peter Vankevich during a DC Audubon field trip to Bombay Hook. As you can see, it is a gull, but its identity is somewhat uncertain. Do you know what species this is? Leave a comment if you think you know. (The gull in question is the one in the center.)
Thursday, July 20, 2006
A federal judge today temporarily stopped construction on a $320 million irrigation project in Arkansas in order to protect the habitat of the ivory-billed woodpecker, whose existence has been hotly debated since a claimed sighting in 2004.
U.S. District Judge William R. Wilson halted the Army Corps of Engineers' Grand Prairie Irrigation Project because federal agencies might have violated the Endangered Species Act by not studying the habitat fully. The construction site is 14 miles from where researchers said they spotted the bird in the swamps of the Cache River National Wildlife Refuge in early 2004. The bird had been presumed extinct for 60 years.
Since then, scientists have published a number of articles claiming the bird was actually a more common pileated woodpecker. Cornell University ornithologists continued their search this summer but to no conclusive avail. Most recently, Arkansas wildlife officials last month offered a $10,000 reward to anyone who can prove the bird's existence (Greenwire, June 22).
Wilson said for legal purposes he had to assume the woodpecker exists in that area. "When an endangered species is allegedly jeopardized, the balance of hardships and public interest tips in favor of the protected species," he wrote. "Here there is evidence the IBW might be jeopardized" (Andrew DeMillo, AP/Washington Post online, July 20). -- DK
Tuesday, July 18, 2006
The hummingbird, known as the Marvelous Spatuletail, is among the strangest and most spectacular of all birds. Adult males have tails that are more than twice as long as their bodies and end in two great ungainly-looking spoon-shaped feathers. The birds are also cloaked in iridescent feathers, and like all hummingbirds, they are highly aggressive despite their small size. Local people once believed the birds conveyed aphrodisiac properties when consumed, likely compounding their problems which already include the conversion of their extremely limited habitat to cattle pasture and agriculture....The American Bird Conservancy has engaged in similar efforts in Colombia to save wintering habitat for the cerulean warbler.
Despite its remote location, the area where the hummingbird lives is already known to birdwatchers. In order to find the species it is often necessary to commission the services of one of the world’s youngest bird guides, ten-year-old Solomon Ortiz-Perez, who for a small fee will lead eager groups of bird tourists up steep slopes to search for the bird. The spatuletail is fast becoming a flagship species for tourism in the area, and has already appeared in travel advertisements in American magazines that aim to attract keen birdwatchers to the bird’s remote habitat. It has also been declared the “Regional Bird” for Peru’s Amazonas region.
Friday, July 14, 2006
Kenilworth Park and Aquatic Gardens
Blooming lilies and lotuses
DC Audubon will be there and lead a bird walk in the gardens. Come meet some of our board members and field trip leaders. Look for our table in the picnic area near the visitors center. There is no need to RSVP for this bird walk; just meet up at our table at about noon.
This is a wonderful time of year to visit the Aquatic Gardens, since most waterlilies and lotuses will be at their peak. In addition to the flowers, the gardens attract a diverse array of breeding and migrant birds. The marsh and river trail offer additional birding opportunities.
Tuesday, July 11, 2006
For North American birders, the results regarding chickadees are intriguing. Though the black-capped chickadee and carolina chickadee interbreed and are similar enough in appearance to make identification difficult, they are not as closely related as one might think. Instead, black-capped is more closely related to the mountain chickadee. Among carolina chickadees, there are significant genetic differences between the two subspecies, the eastern extimus and the carolinensis subspecies in Louisiana. Whether that would be enough to call for a species split is not addressed in the Birding summary.
Monday, July 10, 2006
Changes in this Supplement fall into the following categories: (1) three species are added because of splits from species already on the list (Calonectris edwardsii, Dendragapus fuliginosus, Loxigilla barbadensis); (2) one species is added because of new distributional information (Fregetta tropica); (3) two species replace others presently on the list because of splitting of extralimital forms (Cuculus optatus, Ficedula albicilla); (4) one species name (Streptopelia risoria) is changed because of recognition of its status as a feral form of S. roseogrisea; (5) one family is merged into another (Dendrocolaptidae into Furnariidae), with no resultant nomenclatural changes; (6) one subfamily is elevated to status of family (Stercorariidae), with no resultant nomenclatural changes; (7) one genus (Asturina) is merged with another (Buteo), resulting in a new name combination (B. nitidus); (8) one species (sissonii) is transferred from one genus (Thryomanes) to another (Troglodytes); and (9) two species (Myiozetetes similis, Catharus mexicanus), in addition to three of the four added to the entire list [see (1) and (2) above], are added to the list of species known to occur in the United States.Of these, the one likely to affect the most North American birders is the first. Blue Grouse (Dendrapagus obscurus) has been split into two species, Dusky Grouse (D. obscurus) and Sooty Grouse (D. fuliginosus). The two species were split based on mitochodrial DNA and behavioral evidence. Sooty Grouse inhabits the Pacific coast, while Dusky Grouse claims the interior mountain west. There is an intergrade zone in Washington state. The paper that led to the split is here.
In addition to the changes listed in the first blockquote, the AOU has rearranged species into new genera within the sandpiper and tern families. In the case of sandpipers, species in the
Heteroscelus and Catoptrophorus genera have been moved to the genus Tringa, so that the list is now as follows:
Xenus cinereus Terek SandpiperFive genera have been split from the Sterna genus in the tern family: Onychoprion, Sternula, Gelochelidon, Hydroprogne, and Thalasseus. The new order is as follows:
Actitis hypoleucos Common Sandpiper
Actitis macularius Spotted Sandpiper
Tringa ochropus Green Sandpiper
Tringa solitaria Solitary Sandpiper
Tringa brevipes Gray-tailed Tattler
Tringa incana Wandering Tattler
Tringa erythropus Spotted Redshank
Tringa melanoleuca Greater Yellowlegs
Tringa nebularia Common Greenshank
Tringa semipalmata Willet
Tringa flavipes Lesser Yellowlegs
Tringa stagnatilis Marsh Sandpiper
Tringa glareola Wood Sandpiper
Tringa totanus Common Redshank
Anous stolidus Brown Noddy
Anous minutus Black Noddy
Procelsterna cerulea Blue-gray Noddy
Gygis alba White Tern
Onychoprion fuscatus Sooty Tern
Onychoprion lunatus Gray-backed Tern
Onychoprion anaethetus Bridled Tern
Onychoprion aleuticus Aleutian Tern
Sternula albifrons Little Tern
Sternula antillarum Least Tern
Sternula superciliaris Yellow-billed Tern
Phaetusa simplex Large-billed Tern
Gelochelidon nilotica Gull-billed Tern
Hydroprogne caspia Caspian Tern
Larosterna inca Inca Tern
Chlidonias niger Black Tern
Chlidonias leucopterus White-winged Tern
Chlidonias hybrida Whiskered Tern
Sterna dougallii Roseate Tern
Sterna hirundo Common Tern
Sterna paradisaea Arctic Tern
Sterna forsteri Forster’s Tern
Thalasseus maximus Royal Tern
Thalasseus bergii Great Crested Tern
Thalasseus sandvicensis Sandwich Tern
Thalasseus elegans Elegant Tern
Thursday, July 06, 2006
The researchers calculated that since 1500 -- the beginning of the major period when Europeans began exploring and colonizing large areas of the globe -- birds have been going extinct at a rate of about one species per year, or 100 times faster than the natural rate.
And the rate has been faster in recent times. "Increasing human impacts accelerated the rate of extinction in the 20th century over that in the 19th," the report said. "The predominant cause of species loss is habitat destruction." ...
The new assessment considerably exceeds previous scientific estimates that 154 bird types disappeared during that past 500 years, according to the researchers.
One factor contributing to such large differences in estimates is that "more than half of the known species of birds were not discovered until after 1850, an important point that previous estimates of extinction rates have failed to take into account," Raven said. "One can't register a bird as extinct if it was not known to exist in the first place."
The authors of the piece advise better policies to prevent extinctions. The new report is not all bleak, Pimm said. "The good news in this report is that conservation efforts are reducing extinction rates to about one bird species every three or four years," he said, but he added that even this improved rate "is still unacceptable." Of the 9,775 known species of birds, "an estimated additional 25 would have gone extinct during the past 30 years if it were not for human intervention," Raven said. Despite conservation efforts, "some 1,200 more species are likely to disappear during the 21st century," he warned. "An equal number are so rare that they will need special protection or likely will go extinct, too."
Read the rest.
The new report is not all bleak, Pimm said. "The good news in this report is that conservation efforts are reducing extinction rates to about one bird species every three or four years," he said, but he added that even this improved rate "is still unacceptable."
Of the 9,775 known species of birds, "an estimated additional 25 would have gone extinct during the past 30 years if it were not for human intervention," Raven said.
Despite conservation efforts, "some 1,200 more species are likely to disappear during the 21st century," he warned. "An equal number are so rare that they will need special protection or likely will go extinct, too."
It appears that bird droppings managed to survive the launch of the shuttle Discovery.
NASA's rocket scientists have a new appreciation for the out-of-this-world power of bird droppings. The orbiting space shuttle Discovery sported some whitish splotches on its black right wing edge that NASA officials said appeared to be bird droppings.
Shuttle lead flight director Tony Ceccacci said he saw the same splotches on the identical part of the shuttle about three weeks ago when Discovery was on the launch pad and laughed when pictures beamed back from space Wednesday showed they were still there.
That means these bird droppings withstood regular Florida thunderstorms, a mighty Fourth of July launch during which 300,000 gallons of water is sprayed at the shuttle's main engines, and a burst upward through Earth's atmosphere. During that launch Discovery went from zero to 17,500 mph in just under 9 minutes.
Friday, June 30, 2006
The Potomac Conservancy has a series of events in July that may interest Audubon members.
Independence Day Paddle. Tuesday, July 4, 9 a.m. - 3 p.m., Violette’s Lock (Lock 23) to Tenfoot& Sharpshin Islands. Celebrate Independence day with PotomacConservancy on a five-mile paddle from Lock 23 to the Conservancy’s ownTenfoot and Sharpshin Islands. Come prepared for the weather and bringa sack lunch. RSVP required, canoes and equipment limited but stillavailable. Free. (301) 608 - 1188, x213.
Picnic on the Potomac. Saturday,July 8, 4 - 8 p.m., Caderock Pavillion, Carderock, Md. Come andcelebrate with the Potomac Conservancy at our seventh annual memberpicnic and potluck. Food, games, nature and fun! This PotomacConservancy event is suitable for children. Free. (301) 608 - 1188,x208.
Voices of the River: Fiddlin’ On the Porch.Sunday, July 9, 4 - 5 pm, River Center at Lockhouse 8, C&O Canal,Cabin John, Md. Park at Clara Barton Parkway Lock 8 pullout. Comelisten to the folk fiddle and guitar of Kitchen Gorilla(Lisa Robinson and Joel Edelman) and hear old time tunes of Celtic,Appalachian and Eastern European origin. This Potomac Conservancyevent is suitable for children. Free. (301) 608 - 1188, x 212.
Potomac Heritage Trail Repair Workshop.Saturday, July 22, 9:30 a.m. - 3 p.m., Northern Virginia. Join atraining workshop on trail maintenance and learn how to construct ahiking trail from professionals supported by the ACME Treadway TrailCrew and the Potomac Conservancy! Slots are limited, RSVP required. Contact Bruce Glendening (703) 532 - 9093 or James Tilley (301) 608 -1188, x 213 for more information.
Explore and Restore: Minnie’s Island. Sunday,July 23, 9 am - 2 pm, Minnie’s Island near Lockhouse 8, Cabin John,Md. Come learn about Minnie’s Island, owned and protected by PotomacConservancy! Volunteers will not only cleanup litter, remove invasiveplant species, reestablish trails, but will also explore this treasureand summer beauty of the island inside the beltway. Cool water andsnacks will be provided, RSVP required. Free. This PotomacConservancy event is suitable for children. (301) 608 - 1188, x 211.
Visit Wings Over Water for more information.
Welcome to Eastern North Carolina and the Outer Banks Here you'll enjoy miles of unspoiled landscapes, sandy beaches, rolling dunes, scrub thickets, broad marshes, pocosins, blackwater swamps, and maritime and inland forests. These varied habitats are rich in wildlife. Large acreages are protected as parks, reserves and wildlife refuges.
Autumn is a special time in Eastern North Carolina. The frantic summer tourist season is well past, and the land and water are left to those who wish to blend with nature. Wings Over Water will be your opportunity to enter this land of wildlife enchantment. Through field trips, workshops and interpretive programs, you will explore one of the most fascinating ecological settings in the United States.
Wings Over Water (WOW) offers programs for the amateur-to-serious birder, nature enthusiast, wildlife photographer, paddler, angler, and others who enjoy being up close with nature.
Participants, for a modest cost, can select from such varied experiences as:
- Venturing into areas with combined bird lists of nearly 400 species.
- Visiting North Pond on the Pea Island National Wildlife Refuge on Hatteras Island, the hottest spot for fall birding in North Carolina.
- Traveling to the Cape Hatteras Lighthouse area to search for a variety of shore and water birds.
- Experiencing Ghost Town Birding on Portsmouth Island
- Taking a ferry to the pirate Blackbeard's hang-out on Ocracoke Island to enjoy the quaint fishing village and check out the birds.
- Visiting the ancient maritime forests at Buxton Woods and Nags Head Woods for a look at these rare ecosystems.
- Traveling to Mattamuskeet National Wildlife Refuge where eagles and other raptors are likely the causeway and entrance road.
- Exploring a blackwater swamp in the Alligator River National Wildlife Refuge
- Sliding into a kayak or canoe to explore a salt marsh environment.
- Wade in search of Clapper Rails, marsh sparrows and wrens at Oregon Inlet.
- Heading for the blue waters of the Gulf Stream off Cape Hatteras to search for pelagic birds.
- Experiencing a Red Wolf Howling where the nearly extinct animal is now fighting its way back.
This month's bird is the Myrtle Warbler (pdf). Peter explains:
The Myrtle Warbler, Dendroica coronata, is the eastern subspecies of the Yellow-rumped Warbler. For years it was considered a separate species, but in 1973 the American Ornithological Society "lumped" it with its western counterpart the Audubon's Warbler and the Guatemalan Goldman's Warbler, to make one species. This bird is the most common warbler in North America, and winters in great numbers along the mid and south Atlantic Coastline due to its ability to eat wax myrtle berries in addition to warblers' usual mainstay diet of insects. During migration it has a soft musical song with a slight trill that fades out. In winter, it has a
very distinctive chip note. Note its yellow side patches and black breast and mask. Its primary diagnostic in all plumages is a yellow patch in its lower back easily seen when in flight. Don't expect to find it nesting in your yard, its heading to forests farther north.
Read the rest (pdf).
Thursday, June 29, 2006
Please contact Carolyn Williams at firstname.lastname@example.org or 703.273.1961.
I coordinate the Northern Virginia Bird Survey (NVBS), The Audubon Society of Northern Virginia's breeding bird point-count now in its 13th year. (Until fairly recently ASNV was called the Fairfax Audubon Society.) This year we lost the services of three of our long-time master birders (team leaders) for Manassas National Battlefield Park (two moved from the area and another was overbooked). I am looking for several master birders (defined as one who can identify by sight or sound all the bird species one would expect to encounter in N. Va. during June) to replace them. Our count protocol is a simple one, a one-time, five-minute count at each 250-meter (about 0.15 mile) grid point. The count is done between dawn and about 8:30 a.m. in June.* Master birders can survey alone or with one or more assistants, but only the master birder identifies the birds to be logged in. Information collected includes species, number of individuals, evidence of breeding activity (using codes), date and time of the count, sky and weather conditions (using codes). Flyovers are indicated. Survey instructions, detailed field maps, and data sheets will be provided. About sixty points are involved, and of these twenty-nine have been GPSed. You can survey as many of the points as you like. I am pushing the GPSed points as they have been surveyed the longest. They are located in the north central part of the park.
*Under the circumstances, I think we can extend the deadline to at least July 7.
For further information contact Carolyn Williams at email@example.com or 703.273.1961.
A recent study of West Nile Virus transmission in the DC area found that the number of infections in humans depends on the density of the local population of American Robins. Researchers set up mosquito traps baited with dry ice in several local parks: the 26th Street Dog Run, National Mall, and Fort Dupont Park in DC; and Camden Yards, Takoma Park, and Bethesda in Maryland. Birds at the same sites were caught in mist nets for blood tests.
Robins, it turns out, appear to be taking the hit forhumans, getting sick and dying as did thousands of crows that wereinfected in the first wave of West Nile virus after it arrived in NorthAmerica. Thanks to the robins, humans who frequent the 26th Street dogpark and similar areas have a lower chance of contracting the virus, atleast in spring and early summer months. The reason? To mosquitoes,robins are far more tempting meals.
Then the scene changes.
"Robinsbegin to migrate south in late July and August," Kilpatrick said,"leaving mosquitoes on the hunt for blood from another source."
That source turns out to be Homo sapiens. The number of human infections with the virus shoots up come the dogdays of August. Then it's mosquito vs. man or woman, instead ofmosquito vs. robin.
The authors of the original article in PLoS Biology argue that the pattern of infection - birds in early summer and humans in late summer - has increased the prevalence of the disease in both mosquitos and humans:
Feeding shifts have two synergistic effects on the intensity of WNV transmission to humans. First, we have shown that the increase over time in the probability of Cx. pipiens feeding on humans results in a greater number of human WNV infections than if the mosquitoes fed on humans with the same probability as in early summer (Figure 1C). Second, feeding primarily on WNV-competent avian hosts during the amplification period of the epidemiological cycle maximizes the intensity of the epidemic in mosquitoes.... This is because mosquito WNV prevalences are already beginning to decline (possibly as a result of increased acquired immunity in juvenile birds) when mammals begin to make up an important fraction of the blood meals. Thus, the shift in feeding from competent hosts early in the season to humans later leads first to greater amplification of the virus as transmission intensifies between birds and mosquitoes and subsequently to an even greater number of human WNV infections.
The continuing presence of the West Nile Virus in the DC area is a reminder to take reasonable precautions against mosquito bites, especially in late summer: do not keep standing water around your house; use insect repellent on bare skin or keep skin covered. (See this CDC advice on avoiding bites.)
Wednesday, June 28, 2006
For more information on the whooping crane project, see the website of Operation Migration.
As part of the project, now in its fifth year, cranes hatched in captivity at the Patuxent Wildlife Research Center in Maryland have been raised at the Necedah refuge and led south by ultralight aircraft in the fall to the Chassahowitzka National Wildlife Refuge near Crystal River, Fla. They migrate back north on their own in the spring.
The flock now numbers about 60 birds, with 22 newly hatched young ones being raised for release this fall....
The only other migrating flock of whooping cranes numbers about 200 birds. They fly from Canada to winter on the Texas Gulf Coast. The whooping crane, the tallest bird in North America, was near extinction in 1941, with only about 20 left.
Monday, June 19, 2006
Fossils from China's Gansu Province have shed new light on the early evolution of birds. The fossils show an bird-like species named Gansus yumenensis that lived about 110 million years ago, in the late Cretaceous. Gansus is only about 10-15 million years younger than feathered dinosaurs like Dilong paradoxus.
Artist's rendering of Gansus yumenensis
Gansus yumenensis lived most of its life in water, similar to loons, grebes, diving ducks, and alcids. It shares much of its bone structure with modern birds, and it could certainly fly.
Harris says Gansus shares many skeletal features with modern birds, including the knobby knees characteristic of underwater swimmers like loons and grebes. Moreover, he says, the preserved skin of the webbed feet shows the same microscopic structure seen in aquatic birds today.
"It was unexpected to find a bird this advanced in rocks this old," Harris said. "It tells us that the anatomical features we use to characterize modern birds evolved very quickly."
According to the researchers, Gansus is the oldest clearly established member of the subclass Ornithurae, the group most closely related to modern birds.
Most fossil birds dating so far back belong to a different evolutionary lineage called opposite birds. The name stems from the fact that bones in their shoulders and feet fit together opposite from the way seen in birds today.
Opposite birds made up the dominant bird group of the Cretaceous Period (145.5 to 65.5 million years ago). They disappeared along with the dinosaurs when that period ended, leaving no modern descendants.
The most likely scenario now seems to be that most avian forms died at the end of the Cretaceous but that certain aquatic birds like the Gansus species survived. Modern birds - from ducks to gamebirds to songbirds - then evolved from these aquatic roots. Most of this early lineage has yet to be established, but it will be fun to watch where the bones lead us.
Tuesday, June 13, 2006
Sneak out for lunch. Former vice president Al Gore signs his new environmental book, An Inconvenient Truth: The Planetary Emergency of Global Warming and What We Can Do About It (companion to the documentary film by Davis Guggenheim about Gore's environmental crusade), at Olsson's Books-Penn Quarter.
Thursday, June 15
418 7th St., NW
Washington, DC 20004
(between D & E Streets)
* USA Today Review
Friday, June 09, 2006
Cambridge Commission Gives Blackwater Favorable VoteThis project is near the Blackwater NWR, an important breeding and wintering site for birds and other animals in the Chesapeake watershed. Runoff from the development is expected to set back efforts to clean up the bay. DC Audubon has run autumn field trips to the refuge for several years.
The Cambridge Planning and Zoning Commission on June 6 made a favorable recommendation on the Blackwater Resort Communities development. This is not over -- there is still time to stop this project. The project must still receive a favorable recommendation for the final master plan. It also still needs approval from the Cambridge City Council and the state Critical Area Commission.
We need you to:
1. Come out to upcoming hearings and show your opposition to the project.
2. Hold city officials accountable for their actions.
3. Stay posted on this website and the Blackwater blog for upcoming hearing dates and updated information.
4. Continue to show your opposition to the project--sign the petition, or get a neighbor or friend to sign it; write a letter to the editor about your opposition to the project and ask elected leaders to listen to the will of the people.
Wednesday, June 07, 2006
Friends of the American Association for the Advancement of Science (AAAS) and the journal Science are cordially invited to meet three researchers whose latest fossil analysis will be published in Science on 16 June.
Dr. Hai-lu You of the Chinese Academy of Geological Sciences, Beijing; Dr. Matthew C. Lamanna of Carnegie Museum of Natural History, Pittsburgh, Pennsylvania; and Dr. Jerald D. Harris of Dixie State College, St. George, Utah, will give a lecture and video presentation to take place:
Thursday, 15 June 2006
AAAS headquarters building
12th and H Streets NW, Washington, DC
Metro Center subway stop (one block from AAAS headquarters)
Refreshments will be offered at 6:00 p.m., with the one-hour program to follow at 6:30 p.m.
Seating is limited. All guests are requested to RSVP by contacting AAAS Development at firstname.lastname@example.org or at (202) 326-6636.
The research, directed by Dr. Hai-lu You, is sponsored in part by the Discovery Quest Program for The Science Channel. Guests will be treated to a short clip from The Science Channel's special feature, "Rise of the Feathered Dragons," which will air Monday, 19 June at 9:00 p.m. ET/PT. Details will remain embargoed until the day of release. This research will provide the first peer-reviewed analysis of Dr. You's discovery of bird-fossil specimens preserved in China's Changma Basin. Paleontological discoveries provide a useful springboard for stimulating scientific interest among young people. Invited guests are encouraged to bring their older children (middle school and older).
To RSVP: E-mail email@example.com or call (202) 326-6636.
For more information, see the AAAS webpage.
Tuesday, May 30, 2006
Treasury Secretary John Snow resigned Tuesday and President Bush nominated Goldman Sachs Chairman Henry M. Paulson Jr. to replace him.
The Washington Post reports that Paulson is a birdwatcher who can often be found in Central Park with his binoculars, he is known as a conservationist also serving as co-chair of the Asia/Pacific Council of the Nature Conservancy, and the chair of The Peregrine Fund, which works to conserve wild populations of birds of prey.
In an article in CNN Money/Fortune Paulson was approached by the Nature Conservancy in 2001 to serve as its CEO. "The timing isn't right," Paulson said then. Now instead he takes the helm of Treasury.
* CNN Money/Fortune article on Paulson's Secret Life
* Article in The Washington Post
* Financial Times Profile
* Remember these birds at the Treasury
Thursday, May 25, 2006
Increased harvesting of horseshoe crabs has been blamed for this species's rapid decline. Before a sudden boom in the horseshoe crab market, watermen took only about 100,000 crabs per year; at the height of crab harvesting in the mid 1990s, about 2.5 million crabs were taken. Horseshoe crabs are used as bait for conch fishing.
Red knots depend upon a plentiful supply of horseshoe crab eggs when they arrive at the Delaware Bay in the midst of their long migration from the southern tip of South America to their breeding grounds in the Arctic Circle. Their migration is timed to coincide with the spawning of horseshoe crabs, when millions of horseshoe crabs come ashore on the beaches to mate and lay their eggs.
Tuesday, May 23, 2006
Learn more about coastal plain swamp sparrows.
It was only 55 years ago that the coastal plain swamp sparrow was identified and categorized as a subspecies of the more common swamp sparrow, says Shriver. And just last year Smithsonian researchers discovered where the bird winters -- a stretch of marshland from Charleston, S.C., to Beaufort, N.C. It's not a very long trek; most migratory birds fly far greater distances between their winter and summer homes. But Shriver explains that there's one crucial difference between the habitats -- freezes don't occur regularly in the coastal Carolinas. Coastal plain swamp sparrows feed on insects and spiders, which they find by poking around in the mud, so moving 500 or 600 miles south ensures a steady food supply in the winter months.
Mid-May marks the start of nesting season for the coastal plain swamp sparrow and the start of field research. Studies in Chesapeake Bay marshland have shown a steady drop in the number of sparrow nests since the late 1980s. Shriver and Greenberg want to see if that pattern is occurring in Delaware marshes. Coastal plain swamp sparrows like to nest in high marsh, which features a mix of tall and short grassy vegetation with shrubs mixed in. They often attach their nests to the base of the Hide Tide Bush, a common shrub, and then use tufts of Salt Hay to camouflage the nests. Finding these small, well-hidden nests is a bit like finding a needle in a haystack. Fortunately, the female vocalizes a distinctive "chip, chip, chip" call when
leaving the nest.
Coastal plain swamp sparrows like to nest in high marsh, which features a mix of tall and short grassy vegetation with shrubs mixed in. They often attach their nests to the base of the Hide Tide Bush, a common shrub, and then use tufts of Salt Hay to camouflage the nests. Finding these small, well-hidden nests is a bit like finding a needle in a haystack. Fortunately, the female vocalizes a distinctive "chip, chip, chip" call when leaving the nest.
Sunday, May 21, 2006
Peter Vankevich took this photograph on May 13, 2006 on Capitol Hill, Washington, DC. Several excellent birders have had varying opinions as to its identification. Feel to offer your opinion in the comments.
Saturday, May 06, 2006
May 13, 2006
Celebrate the diversity of resident and migratory bird species on International Migratory Bird Day (http://www.birdday.org/) by participating in a fund-raising Birdathon to benefit the Audubon Society of the District of Columbia.
The Birdathon counting is between 5:00 a.m. through midnight. Teams will count American Bird Association (ABA) recognized species of birds within the terrestrial and nautical boundaries of the District of Columbia. Birds seen on the boundary lines with MD and VA will count.
Rules are the same as the 2005 ABA Big Day Rules with the exception of the time of the Birdathon and each bird species must be seen or heard by 2/3 of the team members. If you are a team of only two members, you both must identify the bird.
To refer to the additional rules visit here:
All teams must seek pledges for donations to the Audubon Society of the District of Columbia. Non-residents of DC may participate. Non-members of the Audubon Society of the District of Columbia may participate. Participants are recognized when their lists are submitted no later than May 20. There is no entry fee. Please create a team name and enter it with your submission. We are operating on the honor system for sightings, but the Society has the right to question and challenge unusual sightings.
Typically, ask for a pledge per bird seen or heard and tell your donors how many species you hope to target.
Winners – everyone that cares about bird conservation is a winner, but the team with the most sightings will be recognized on the Audubon Society of the District of Columbia’s Web site. Please include a team picture and your names with your submission so that you may bask in the glory of your victory.
Make checks payable to the Audubon Society of the District of Columbia.
Submit checks, team information and final counts using the ABA form to the following:
Send checks to Audubon Society of the District of Columbia, c/o Denise Ryan, Treasurer
5726 Lockwood Rd, Cheverly, MD 20785
Participation or rules questions to Denise Ryan at firstname.lastname@example.org
Tuesday, May 02, 2006
Thursday, April 27, 2006
May 4 lecture at the National Zoo: Chivalry Is Dead in Migratory Birds: Lessons From the Winter Season
Chivalry Is Dead in Migratory Birds: Lessons From the Winter Season
The relationship between male and female migratory birds during the breeding season appears idyllic: Both members of a breeding pair vie for each other's attention, cooperate to bring food to their nestlings, and, in some cases, even raise a second brood together. Things change dramatically during the winter season in the tropics. There, it's a battle of the sexes. Males compete with females for the best habitats—and usually win. As a result, females suffer lower survival. Peter P. Marra of the Smithsonian Migratory Bird Center will talk about this and other discoveries of his 15-year research program on the winter ecology of migratory birds in Jamaica. This lecture is part of the Zoo's celebration of International Migratory Bird Day.
The lecture is FREE, but please RSVP at http://nationalzoo.si.edu/ActivitiesAndEvents/Lectures/rsvp.cfm. The lecture is in the National Zoo's Visitor Center, just off Connecticut Avenue. Take public transportation, or drive through the vehicle entrance at Connecticut Avenue and park in Lot A.
Tuesday, March 21, 2006
From The Discovery Channel: A Scotsman with a heavy brogue may speak the same language as a Texas cowboy, but each has a distinct accent; now researchers have discovered that female whipbirds in Australia sing the same basic songs, but with regional accents.
Female birds in general rarely sing, so that find itself is unusual. The determination is doubly noteworthy because the scientists observed that the males of this species, Psophodes olivaceus, sing with no accent whatsoever.
Mennill and his colleague Amy Rogers measured eastern whipbird recordings from 16 different populations along the east coast of Australia. For each of the 112 birds that they recorded, they measured the song's number of syllables, the length of the first syllable, the highest and lowest frequency of the last syllable, the time between these frequency extremes and other characteristics.
The vast majority of female recordings showed variations on each of these criteria, but male songs were all virtually identical.
In terms of accents, he said that geographical variations, or dialects, are found in other songbirds, whales, seals and primates.
Findings were published in a recent issue of the Journal of Avian Biology.
Friday, March 17, 2006
Since Chimney Swifts thrive in urban areas, the DC Metropolitan area is a prime location to see them. Keep your ears and eyes altert for them.
The first Chimney Swifts of 2006 have been spotted on the Gulf Coast. Once again this year we will be plotting the swifts' movements northward over the next few months. Please let us know when you see the first ones in your area. The results will be posted on our web site at:
You can help us get the word our by passing this message along to any groups or organizations who might want to contribute.
We look forward to hearing from you!
Paul and Georgean
Driftwood Wildlife Association1206 West 38th, Suite 1105Austin, TX 78705
Please visit our web site.
Thanks to our friends at Travis Audubon Society for sending out this message for us.
Thursday, March 09, 2006
The free event will include bird walks, lectures, and demonstrations
with live captive raptors. There will also be several hands-on
workshops and activities for kids. To reach the refuge, follow the directions here.
The Friends of Blackwater have set up webcams at the nests of an osprey and a bald eagles.
Blackwater is the site of DC Audubon's annual November fieldtrip. You can read about our last trip there at our website.
Wednesday, March 08, 2006
The film, On the Edge: The Potomac River's Dyke Marsh has its World Premiere at the DC Environmentalist Film Festival. Dyke Marsh is one of the largest naturally-occurring freshwater tidal marshes in the national park system. A 380-acre wetland, Dyke Marsh is a remnant of the extensive marshes that once lined the river but have been lost to human activity. Congress preserved it in 1959, saying that here, wildlife values should be “paramount.” Naturalist Louis Halle wrote in the 1940s that Dyke Marsh was “the nearest thing to primeval wilderness in the immediate vicinity of the city [Washington].”
Like most vanishing tidal marshlands from Maine to Louisiana, it is disappearing as the result of a myriad of human abuses. As a safety buffer against hurricanes and floods, an ancient hatchery for bay and ocean fish and a focal point for migrating birds, Dyke Marsh affects all of our lives. This film provides a glimpse into the rich diversity of flora and fauna supported by the marsh and contrasts its health today to its condition in the past. The return of the Bald Eagle and the Osprey to the marsh is contrasted with the loss of habitat for most other resident species. Incorporating some of the marsh's historical lore, On the Edge, enlivened by an original soundtrack with Didgeridoo and rainforest percussion instruments, is a primal call to revive the diversity of life that provides sustenance and safety to the species that is destroying the country's tidal marshes–human beings.
The John F. Kennedy Center for the Performing Arts
The Atrium, Terrace Level, New Hampshire Ave. at Rock Creek Pkwy.
March 21 at 7:00 p. m
Old Town Theater
815 King Street, Alexandria
March 28, at 7:30 p.m.
Friends of Dyke Marsh is a volunteer group dedicated to preserving and enhancing Dyke Marsh, the last enduring substantial freshwater tidal marsh in the Washington, D.C. capital area, located on the Potomac River just south of Alexandria, Virginia. Dyke Marsh is administered by the National Park Service. Join Friends of Dyke Marsh.
The article recounts the tale of the finches that misled Darwin. There are 14 finch species in the Galápagos that have all evolved from a single ancestor over the past few million years. They have become one of the most famous cases of species adapting to different ecological niches. From Darwin’s specimen notebooks, it is clear he was fooled into thinking that some of the unusual finch species belonged to the families they have come to mimic through a process called convergent evolution. For example, Darwin thought the cactus finch, whose long, probing beak is specialized for obtaining nectar from cactus flowers (and dodging cactus spines), might be related to birds with long, pointed bills, such as meadowlarks and orioles. He also mistook the warbler finch for a wren. Not realizing that all of the finches were closely related, Darwin had no reason to suppose that they had evolved from a common ancestor, or that they differed from one island to another.
The author's own discovery, more than 30 years ago, that Darwin had misidentified some of his famous Galápagos finches led him to the Darwin Archive at Cambridge University Library, in England. There he found a manuscript trail that poked further holes in the legend that these birds precipitated an immediate “aha” moment. It was only after Darwin’s return to England, when experts in herpetology and ornithology began to correct his Galápagos reports, that he realized the extent of his collecting oversights and misidentifications. In particular, Darwin had failed to label most of his Galápagos birds by island, so he lacked the crucial evidence that would allow him to argue that different finch species had evolved separately while isolated on different islands of the Galápagos group.
Five months after his return to England, in March 1837, Darwin met with ornithologist John Gould. Five years older than Darwin, Gould was just beginning to become known for his beautifully illustrated monographs on birds, which today are highly prized collectors’ items. One of my most unexpected discoveries in the Darwin archives was the piece of paper on which Darwin recorded his crucial meeting with Gould. This manuscript clearly shows how Darwin’s thinking began to change as a result of Gould’s astute insights about the Galápagos birds. Unlike Darwin, Gould had instantly recognized the related nature of the Galápagos finches, and he also persuaded Darwin, who questioned him closely on the subject, that three of his four Galápagos mockingbirds were separate species rather than “only varieties.” Gould also informed Darwin that 25 of his 26 land birds from the Galápagos were new to science, as well as unique to those islands.
Gould’s taxonomic judgments finally caused Darwin to embrace the theory of evolution. Stunned by the realization that evolving varieties could break the supposedly fixed barrier that, according to creationism, prevents new species from forming, he quickly sought to rectify his previous collecting oversights by requesting island locality information from the carefully labeled collections of three Beagle shipmates. Two of these collections, by Captain FitzRoy and FitzRoy’s steward, Harry Fuller, contained 50 Galápagos birds, including more than 20 finches. Even Darwin’s servant, Covington, had done what Darwin had not, labeling by island his own personal collection of finches, which were later acquired by a private collector in England. The birth of the Darwinian revolution was a highly collaborative enterprise.
The case for evolution presented by this shared ornithological evidence nevertheless remained debatable for nearly a decade. Darwin was not entirely convinced Gould was right that all the finches were separate species, or even that they were all finches. Read more.
March 19, 2006
RSVP, contact trip leader Paul DeAnna
DC Audubon will tour this noted birding hot spot, part of the McKee-Beshers Wildlife Management Area, located in Montgomery County Maryland. This is a mosaic of diverse wetland habitats interspersed with mature deciduous forest, hedgerows, and open fields in various stages of transition. The area is bordered on the north by deep marsh and open water in three impoundments covering about 60 acres, and on the south by the Potomac River and adjacent C&O Canal. Migrating waterfowl should be present. Red-headed woodpeckers are among the resident birds. We have timed the trip in hopes of witnessing the return of the tree swallows.
DIRECTIONS (Please consult a map since odometer readings can vary): From the Capital Beltway (495) take exit 39 for River Rd. (MD 190) 3.3 miles north to the 2nd traffic light in Potomac (intersection with Falls Rd.). Continue on River Rd. 7.9 miles to the T-junction with Rt. 112 (Seneca Rd.). Follow River Rd. to the left at this stop sign for another 4.4 miles to the intersection with Hughes Rd., turn left, and drive about 200 yards to the first parking area on the right, where a gated road divides the large impoundments.
On a recent Sunday, Metehan Özen -- one of Turkey's foremost birdwatchers -- trained his $1,500 Leica telescope on an orange-chested Merlin falcon and watched it devour a smaller bird in a flurry of claws, flying feathers and blood.
A few days earlier, two boys played with a dead crow, developed a fever and were brought to Dr. Özen's pediatric hospital ward. There, the specialist in infectious diseases monitored them closely for signs of bird flu.
For years Dr. Özen's hospital job and his hobby existed in unconnected worlds. As Turkey grapples with the bird-flu outbreak here that has quickly infected at least 21 people and killed four, the doctor's two callings have put him in the middle of the quest to understand the virus and contain its spread.
Fellow doctors used to tease him about birdwatching. Not anymore. Over the past two weeks, as the virus rolled out across Turkey, the 37-year-old Dr. Özen briefed the country's top public-health officials about the epidemiology of avian flu and about the migratory routes of wild birds. They are suspected of introducing the virus to domestic poultry, which in turn can infect people. He took a long bus drive amid heavy snowfall and howling wolves to get to the scene of the first human cases near the Southeastern town of Van. There, he saw infected children and their chest X-rays, and visited the parents of three who had died. He helped draft the government's measures to combat the virus, including culling poultry and isolating domestic birds from humans and wild birds, and persuaded officials to ban the hunting of all wild fowl.
In September, Dr. Özen warned colleagues at a medical congress that wild birds could bring avian flu to Turkey during the winter migratory season, and that is now an accepted theory. Trade in infected poultry is another means for the virus to spread. "When you compare maps of migration patterns with maps showing bird-flu outbreaks, they often match each other," said Mehmet Ali Torunoglu, the head of the communicable diseases section at Turkey's ministry of health. "Metehan seems to be right."
In late 2004, Dr. Özen tracked a satellite-tagged goose as it flew from Northern Russia, down to Kazakhstan, Eastern Turkey and Iraq, and then back. The goose's stops along the route gave Dr. Özen ideas about how the virus could spread through migratory flyways.
After visiting Van, Dr. Özen spent some time working with a team of experts at the Turkish health ministry's crisis center in the capital of Ankara. When he returned home, bad news awaited him at his hospital. The two young boys who had found a dead crow in their backyard had a mild form of viral pneumonia, a possible symptom of bird flu. In its human form, the virus often attacks the lungs and causes them to fail. Dr. Özen put the boys in an isolated ward, and waited uneasily for the results of tests that can determine bird flu.
They came back negative. So after his tense week, Dr. Özen headed out into the countryside for his usual pastime, but with a difference: Avian flu was never off his mind. Now, "every bird you see is suspect," Dr. Özen says.
He awoke at 6 on Sunday morning and set off to explore the rich avian world of the Karakaya lake on the outskirts of Malatya, an Eastern Anatolian town known mostly for its apricot orchards. Accompanied by two buddies -- a plastic surgeon and a railroad worker -- Dr. Özen was soon announcing the sightings of particularly interesting birds by chanting "aha, aha, aha...ha-ha-ha!"
A stocky beige barn owl, drowsy and slow in the early morning sunshine, was being chased and harassed by two nimble magpies swerving around it like two fighter-jets. A group of gray herons, their long necks recoiled for a nap, stood motionless on the shore. Two pygmy cormorants, an endangered species, flew across the bright blue sky. Thousands of ducks and Armenian gulls, their numbers swelled by winter migration, crisscrossed the lake.
In the village of Toygar, right on the shore of the Karakaya lake, several roosters crossed the road and headed toward the water to mingle with hundreds of wild ducks. "This is exactly what I fear," Dr. Özen said. For most people, close contact with wildfowl is extremely rare, but domestic poultry routinely mix both with wild birds and with people. Sure enough, two children hopped off a donkey cart next to a wooden shack and approached the roosters.
Since then, he has sighted around 370 species out of Turkey's estimated 456, and he is at work on a "Birds of Turkey" volume. He and his buddies are now preparing a trip to look for a bird called the Great Bustard because at 26 pounds it's the heaviest thing flying in these parts.