Fort Mason: Birding Hotspot

Fort Mason: Birding Hotspot

By David Assmann
Community gardens provide an easily accessible retreat from the concrete jungle of a city, even a city as scenic as San Francisco. What makes them even more idyllic is that they are filled with vibrant bird life. Fort Mason not only has a community garden open to the public, but is also one of the top birding hotspots in the city, with an eBird list of 180 species.
Situated on a bluff above the Bay, the key to Fort Mason’s diversity of bird life is its location and varied topography, providing a refuge for aquatic and land birds as well as migrants. One of the attractions of this birding hotspot is its compactness — upper Fort Mason, which is the main birding area, is only 68 acres in size, making it an easy place to bird, even if you have only an hour.
Fort Mason wasn’t always a hospitable site for birds. First reserved for the U.S. military in 1850 because of its strategic location, Fort Mason was the U.S. Army’s major West Coast shipping port until the end of the 1950s. More than 1.6 million members of the military traveled through Fort Mason on their way to the Pacific during World War II. What is now the Great Meadow was entirely covered by buildings until the 1970s, when Fort Mason became part of the first national urban park, the Golden Gate National Recreation Area.
Fort Mason's Great Meadow in the fog / Photo by David AssmannFort Mason’s Great Meadow in the fog / Photo by David Assmann
Since I started birding, Fort Mason has become my guide for the changing of the seasons. It isn’t fall for me until the Red-Breasted Sapsucker returns from the Sierra at the end of September to take up residence for the winter at Fort Mason. I know winter has ended in late March when the same sapsucker spends a day roaming around Fort Mason instead of sticking to its adopted trees and then disappears, headed for the mountains.
Similarly, I don’t consider it winter until the Red-Breasted Mergansers swim in Aquatic Park in December. I know winter is drawing to a close when the Allen’s Hummingbirds show up in February. The first Western Kingbird migrating through marks spring for me. Summer begins when the resident Downy Woodpeckers and Pygmy Nuthatches start raising young. (Last year a pair of each raised their young in the same tree with nest holes less than a foot apart.)…

Two new Barn Owl homes, awaiting residents

Two new Barn Owl homes, awaiting residents

By Marj Blackwell
Hey Barn Owls! Two new custom-built family homes have been installed on eucalyptus trees in your favorite hunting grounds in Oakland and await your arrival.
The new nest box homes are located within a half-mile of your longtime, current nesting site — a shallow cavity, high in a palm tree near Mountain View Cemetery.   We thought it was time to provide some new safer housing for your offspring.
The well-constructed boxes are based on a design by Steve Simmons, renowned designer/builder of nest boxes for Wood Ducks, Barn Owls and other birds in the Central Valley. They were built by  Bill Blackwell, an expert wood craftsman, who followed Simmons’ detailed design instructions to a T. The boxes are made of exterior plywood, measure 24 x 16 x 12 inches, and weigh 24 pounds apiece. Each has two hinged doors (one for cleaning, one for monitoring), an interior divider, an elliptical entrance hole, and grip grooves instead of a perch.
Finding the right sites for your new nest boxes took considerable research and time. First was the search for strong, straight tree trunks that face open areas near the rodent-populated hillsides in Mountain View Cemetery. Surprisingly, a few property owners rejected the idea of nest boxes on their trees. Finally, I located an ideal eucalyptus tree on private property adjacent to the cemetery, and another eucalyptus tree in nearby St. Mary Cemetery, with permission willingly granted by both property owners.
It's a long way up if you're not an owl! / Photo by Doug MosherIt’s a long way up if you’re not an owl! Carla Din installing a box / Photo by Doug Mosher
Mike Bull, Marj Blackwell, Bill Blackwell, and Doug Mosher / Photo by Carla DinMike Bull, Marj Blackwell, Bill Blackwell, and Doug Mosher / Photo by Carla Din
It took the super skill and strength of Golden Gate Bird Alliance volunteers Doug Mosher and Carla Din, with the help of Berkeley resident Mike Bull, to lift and install the bulky boxes eight feet above ground. Not only did this hardy team ensure the boxes are securely bolted to the trees and perfectly level, they also filled the floors with wood chips to prevent eggs from rolling around.
So now, Mr. and Mrs. Barn Owl, when it comes time for you to start nest hunting in early spring, we hope you will check out these new homes and give one a try. We know you and your lifetime mate always return to the same nesting site, but the boxes definitely are safer for your owlets than a palm tree cavity.…

Endangered Alameda terns get a secure home

Endangered Alameda terns get a secure home

By Richard Bangert
Alameda’s nesting colony of endangered California Least Terns has a new government landlord – and a secure home for the future.
After years of negotiations, the U.S. Navy transferred 624 acres of its former airfield at Alameda Point to the Department of Veterans Affairs (VA) on Monday, November 3.
The transfer includes the former airstrip that was adopted by Least Terns for nesting in the 1970s and that has become the most productive breeding site in California for that species. More than 500 acres – including the area used by the terns – will be preserved as a wildlife reserve.
Golden Gate Bird Alliance and its Friends of the Alameda Wildlife Reserve committee have advocated for decades to protect the terns, whose total population as a species stood at only about 600 pairs in the mid-1970s.
GGBA Executive Director Cindy Margulis congratulated the VA on the transfer and said she looked forward to working together on wildlife protection.
“Locating this state-of-the-art care facility next to this vital permanent wildlife sanctuary containing endangered species calls for all of us to be creative, resourceful, and cooperative,” Margulis said. “This site evokes the spirit of America the Beautiful and should be a very special place for those who serve our country and also steward its natural resources.”
Navy Property Caretaker Doug Delong; US FWS Site Manager Susan Euing,; Leora Feeney from GGBA/Friends of the Alameda Wildlife Reserve; and VA project manager Larry Janes in the Alameda Theater lobby following the Alameda Point transfer ceremony on November 3. / Photo by Richard Bangert Navy Property Caretaker Doug Delong; US FWS site manager Susan Euing; Leora Feeney from GGBA/Friends of the Alameda Wildlife Reserve; and VA project manager Larry Janes in the Alameda Theater lobby following the Alameda Point transfer ceremony on November 3. / Photo by Richard Bangert
GGBA volunteers clean and prepare the tarmac nesting site for the terns'  arrivalGGBA volunteers clean and prepare the tarmac nesting site for the terns’ arrival in 2009
Tern feeding chick next to shelter provided by volunteers / Photo by Richard BangertTern feeding chick next to shelter / Photo by Richard Bangert
The VA plans to construct an outpatient clinic that includes ambulatory surgical care, an office to assist veterans in obtaining benefits, and a national cemetery. The design phase of the $208 million project is expected to be completed in the spring of 2015, with subsequent phases dependent upon Congressional budget authorizations.
Kimberly Ostrowski, the Navy’s keynote speaker at the transfer ceremony, noted that the project faced significant hurdles over the past decade — one of which was the proximity of the VA facilities to the terns’ nesting site. That ultimately led to moving the clinic further away from the nesting area. Master of Ceremonies Dr. Ronald Chun, manager of the Oakland VA clinic, acknowledged the terns’ partnership in the VA’s future by bringing a model of a Least Tern to the podium.…

Why so many Acorn Woodpeckers?

Why so many Acorn Woodpeckers?

By Bruce Mast

They are the clowns of the oak savannah — Acorn Woodpeckers — with their harlequin faces, gregarious habits, and off-kilter laughing calls that inspired Woody Woodpecker. According to Birds of North America, the “Acorn Woodpecker is a common, conspicuous inhabitant of foothill and montane woodlands from northwestern Oregon, California, the American Southwest, and western Mexico through the highlands of Central America to the northern Andes in Colombia. Throughout its range, this species is closely associated with oaks (genus Quercus) and is most commonly found in pine-oak woodlands.”

Here in the Bay Area, Acorn Woodpecker colonies are fairly common in the East Bay hills and the western slopes of Mount Diablo, particularly where there are concentrations of valley oaks. South of Livermore, they can be locally abundant in the Diablo range. They are rare in Tilden and Redwood Regional Parks and practically unheard of west of the Hayward Fault.

So what’s up with the recent spate of Acorn Woodpecker sightings in urban San Francisco and the East Bay lowlands?

Acorn WoodpeckerAcorn Woodpecker at Sycamore Valley Open Space Preserve (Danville) / Photo by Larry and Dena Hollowood, www.flickr.com/photos/larry_dena/ Acorn WoodpeckerAcorn Woodpecker carrying an acorn / Photo by Larry and Dena Hollowood, www.flickr.com/photos/larry_dena/

Beginning around September 1st, Acorn Woodpecker reports started rolling in from multiple East Bay sites from Oakland to Richmond. The irruption hit San Francisco by September 12 when twelve birds were noted flying over Battery Godfrey. S.F. birders started finding bands of Acorns in Buena Vista Park, Lincoln Park, and Golden Gate Park, and solo flyover birds were all over town.

This irruption is particularly noteworthy because Acorn Woodpeckers are not migratory. What’s driving it? The most likely answer is acorn crop failure.

True to their name, Acorn Woodpeckers are acorn specialists. They develop communal granaries that may consist of tens of thousands of holes drilled in tree trunks and limbs, each stuffed with an acorn. Only about half their diet actually consists of acorns — the other half is made up of fruit, insects, and other vegetable matte r— but the acorn granaries are the staple food source that gets them through lean times. Again quoting BN:

[i]n areas where there are large seasonal fluctuations in insects and other foods, year-round residency is dependent on the birds’ ability to store sufficient acorn mast to provide food throughout the winter. Groups that exhaust their stores often abandon their territories and wander off in search of alternative food.

Snowy Plovers arrive — and benefit from new fencing

Snowy Plovers arrive — and benefit from new fencing

By Ilana DeBare

Remember the line from Field of Dreams: Build it and they will come? 

The East Bay Regional Park District built protective fencing this fall on Crown Beach in Alameda.

And the Western Snowy Plovers came!

We posted earlier this month about how Golden Gate Bird Alliance volunteers helped win protective signage and fencing for these small, threatened shorebirds at Crown Beach. Shortly after the fencing was installed, the first plovers of the season arrived and started roosting in and near the protected area.

Not only that, the initial group of about a half-dozen plovers includes one young bird that is only four months old!

Birder Bob Sikora managed to capture photos of some of the Alameda plovers on Wednesday, including one bird with colored leg bands. It turned out to have been banded this past summer by San Francisco Bay Bird Observatory at Ravenswood Slough in Palo Alto, shortly after its birth on June 21st.

Last winter, GGBA volunteers spotted a banded adult plover at Alameda that also came from Ravenswood.

“It’s possible they could be from the same family — that this young bird’s father led it over to Alameda,” said GGBA Executive Director Cindy Margulis. “The arrival of this bird shows that a new generation has come to the beach. Now that the plovers have a protected wintering area here, they will have an easier time maturing and getting used to life in the wild.”

Western Snowy Plover at Crown BeachFour-month-old Western Snowy Plover with leg bands at Alameda’s Crown Beach / Photo by Bob Sikora, bobsikora.smugmug.com Western Snowy Plover at Alameda's Crown Beach / Photo by Bob SikoraWestern Snowy Plover at Alameda’s Crown Beach / Photo by Bob Sikora, bobsikora.smugmug.com

The protected area on Crown Beach — only about two blocks long — is a small but important step in ensuring the survival of Western Snowy Plovers. Due to decades of urban development along western beaches and sand dunes, there are only about 2,000 of these birds left on the West Coast.

Western Snowy Plovers were listed by the federal government as a threatened species in 1993. Beaches like Alameda provide winter roosting sites, where the birds feed and rest in preparation for summer breeding.

But on busy urban beaches — where they are constantly flushed from the warm sand by joggers, dogs, and other passersby — it can be difficult for plovers to get the rest they need. Thus the importance of providing fenced-off protected areas like the one in Alameda!…