Friday, June 30, 2006

Upcoming Events

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.

Wings Over Water

Registration is open for the tenth annual Wings Over Water festival on the North Carolina coast. This year's festival runs November 7-12.

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.
Visit Wings Over Water for more information.

Spotted on the Hill

The Hill Rag, a free monthly publication about life in the Capitol Hill neighborhoods, now has a column featuring the writing and photographs of longtime DC Audubon member Peter Vankevich. The column, called "Spotted on the Hill," profiles birds that are commonly seen in Washington. Each photograph was taken somewhere on Capitol Hill.

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).

Past columns:

Thursday, June 29, 2006

Volunteer birders needed at Manassas!

Interested in being a volunteer birder for Manassas?!?!

Please contact Carolyn Williams at cwilliae@gmu.edu 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 cwilliae@gmu.edu or 703.273.1961.
Thanks.
Carolyn

West Nile Virus Depends on Robin Distribution

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

Whooping Cranes

Earlier in the week, it was reported that a pair of whooping cranes in Wisconsin had possibly hatched a chick. Well, now this news has been confirmed, and it turns out that the pair hatched not one, but two chicks. For the first time in over 100 years, there are now whooping cranes breeding in the wild in the eastern United States.

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.

For more information on the whooping crane project, see the website of Operation Migration.

Monday, June 19, 2006

Earliest Birds May Have Been Aquatic

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

High Noon With Al


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
Noon
418 7th St., NW
Washington, DC 20004
(between D & E Streets)
202-638-7610

* USA Today Review

Friday, June 09, 2006

Blackwater Resort Moves Ahead

From the Chesapeake Bay Foundation:

Cambridge Commission Gives Blackwater Favorable Vote

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.
This 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.

Wednesday, June 07, 2006

Bird Fossil Presentation Next Thursday at the AAAS

Next Thursday, June 15, the American Association for the Advancement of Science will host a program on the early evolution of birds based on analysis of bird fossils. The lecture is free and open to the public.
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 development_events@aaas.org or at (202) 326-6636.

Additional Information
-------------------------------------
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 development_events@aaas.org or call (202) 326-6636.

For more information, see the AAAS webpage.