By Verne Nelson

Yesterday I saw two crows perform the mating ritual. As I discovered later on the Internet, apparently this is rarely observed because it is only done at bond formation and the bond lasts for life.

It happened in a parking lot. I was sitting on a bench in view of it when I heard odd but crow-like sounds. Can’t remember the sound, however when I looked I saw the male standing over a half-crust of bread. He looked directly at the female, calling her plaintively, and then prostrated his body to the ground over the bread with wings fanned beautifully in a full, flat, iridescent spread.

The female approached with a kind of dance, bowing and partially spreading her feathers while vocalizing. When they were finally face-to-face they clipped (without menace) at each others beaks like two scissors. Then the male rose and mounted the female while she crouched and twisted her bottom around to allow mating. As with most birds, that was over in a second. Then the female flew off silently to a high, bare-branched tree and perched.

The male followed soon after, also in silence, and perched nearby on a separate branch. The bread was abandoned. After about 20 seconds they both flew off together, again in silence. They may have been near their nest.

And me, without a camera, but otherwise — WOW!

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Verne Nelson is a former statistician in the field of epidemiology, now retired for nine years. His avocation is bird photography and observing nature in urban areas and wildlife preserves. This post is reprinted with Verne’s permission from the East Bay Birding Yahoo Group.…

By Jack Dumbacher

What iconic north American bird used to be the most abundant bird species on earth, but is definitely not on your life list?  The Passenger Pigeon, Ectopistes migratorius.  But if Bay Area innovators Stewart Brand and Ryan Phelan have their way, you may be able to see them again, live in feathered form.

Extinction – the end of a gene pool – is regarded as the final step from which there is no return.  It is as final as final can be.  Extinction is something to be feared and respected, and many conservation workers spend their lives trying to prevent their favorite species from slipping into this oblivion.  But is it really final?

There is a growing team of people — led by Brand, whom you may remember as publisher of the Whole Earth Catalog from the 1960s through the ’90s — who are asking whether de-extinction is possible.  They have gathered geneticists, ethicists, behaviorists, evolutionary biologists, all to turn their tools and creativity to de-extinct a single species.

The species they have chosen as their flagship goal is the Passenger Pigeon.

Museum specimens are all that is left of the Passenger Pigeon, but there are many in collections from around the world. Most are well preserved, and tissue from feet and skins are excellent sources of DNA for genome sequencing work. / Photo by Jack Dumbacher

Apart from being the quintessential American extinction, it has a few things going for it.  Just a couple years ago, genetic data suggested that its closest living relative is the Band-tailed Pigeon (Patagioenas fasciata), and not the Mourning Dove as many had thought [1].  This suggests that the Band-tailed Pigeon may be able to act as a surrogate parent and sort of genome template.

New technology is available that is allowing Beth Shapiro at U.C. Santa Cruz and colleagues to sequence the whole genome of the Passenger Pigeon from snippets of century-old museum skins.  Geneticists like George Church at Harvard Medical School are developing techniques for taking a closely related genome (i.e. the Band-tailed Pigeon) and performing “site-directed mutagenesis” to carefully alter the key genes that differ between the two, and make them more like the Passenger Pigeon.  Using these technologies they don’t have to create the entire Passenger Pigeon genome from scratch; they can modify the Band-tailed genome so that it becomes effectively a Passenger Pigeon.

Band-tailed Pigeon in New Mexico / Photo by Peter Wallack

Once the genome is reconstructed, they will need other folks who can transfer it into the nucleus of a living cell, and then transfer that nucleus into an egg. …

By Glenn Stewart

At this moment, thousands of people are nervously watching the falcon nest camera atop the PG&E headquarters building at 77 Beale Street in downtown San Francisco. The female Peregrine Falcon nesting there since 2008 has disappeared and a new female has moved in to the territory.

All Peregrine Falcons look similar but not exactly alike. Variations in plumage on the head and neck make it possible to differentiate among adults. For example, some have a full black hood while others have more discernible malar stripes over their eyes. Markings on the upper chest area vary as well.

I will provide some background before reviewing the drama unfolding at this nest.

After we at the Santa Cruz Predatory Bird Research Group were involved in the Peregrine Falcon recovery from the mid-1970s to mid-1990s, we began watching the Bay Area population as a manageable sample of the statewide population. Today, we try to monitor about thirty Peregrine Falcon nests for occupancy and productivity from Marin to Monterey counties, and east to Contra Costa and Santa Clara counties. We enter nests to band about 25 nestling Peregrine Falcons each year.

Lil and her mate Dan exchange places on the nest in February / Photo from SCPBRG nest cam

During 2012, we followed 12 pairs nesting on traditional cliffs and another 12 pairs that we refer to as urban pairs because they use buildings, bridges and cranes as nest structures. It was interesting that the urban birds were more productive, producing an average 2.25 young per site while those on natural cliffs produced an average of 1.66 young.

The first post-DDT-era Peregrine Falcons seen in the Bay Area appeared on the Bay Bridge in 1983. The female was found shot to death a few months later near the duck blinds adjacent to the Bay Bridge Toll Plaza. Peregrines began using sites on both the east and west spans of the Bay Bridge in following years with little success. The bridge proved advantageous for staging hunting forays but was lethal for fledging youngsters, due to the long distance to land and paucity of perches below the roadbed for clumsy fledglings.

When we found peregrines hunting downtown, we put a nest tray filled with gravel on an unused 33rd story balcony of the PG&E building. The building was a favorite perch in the late 1980s but the nest tray was not used until 2003.…

By Ilana DeBare

As residents of San Francisco and the East Bay, we in Golden Gate Bird Alliance are all pretty much urban birders.

But David Lindo is The Urban Birder.

A native of London, Lindo has built a career around extolling the wonder of birding in cities. He’s done books, TV shows, tours and writes a blog called (of course) The Urban Birder.

“I’m all about trying to engage people who haven’t declared an interest in birds,” he said during his first visit to the Bay Area last week. “I see myself as a conduit, a gateway, a bridge. It’s all about looking up and realizing nature is all around us, not just on the TV or off in the countryside.”

When we learned that Lindo was visiting California, we got together with our partners at Outdoor Afro and hosted a small reception for him. We hope to sponsor him at a large public speaking event the next time he visits here.

David Lindo and Eagle Owl / Photo by Darren Crain

Lindo, 49, walked an unlikely path to birding. He grew up in a working-class black and Irish neighborhood in North London where he knew no one with any interest in birds. But he was fascinated by wildlife from early childhood – a “twitcher in the womb,” as he puts it, using the British word for a highly competitive birder.

“I’d look around and decide that sparrows were ‘baby birds’ and starlings were ‘mommy birds.’ It wasn’t until I was around seven and went to the library that I knew what they were called. I read things voraciously. By the age of eight, I was a walking encyclopedia on the birds of Britain.”

Lindo’s  first adult birding mentor was a foreman from his father’s factory who was an “egger” – a devotee of a British pastime, popular in Victorian times but now vilified by conservationists, of collecting eggs out of nests.

“Luckily I wsn’t contaminated with the egg collecting gene,” he joked.

Lindo uses his race, enthusiasm and humor to break down British stereotypes of birders.  “In Britain a lot of people have the impression that birders are male, big-bellied and white – dull people,” he said. “I break that stereotype in many ways. People think that birds are geeky or for nerds, but then they hang out with me and realize it is quite fun and contemporary.”…

Editor’s Note: Golden Gate Bird Alliance member Alan Krakauer is studying Greater Sage-Grouse behavior in Wyoming. A longer version of this post appears on his blog.

By Alan Krakauer

One of North America’s most spectacular birds is also a species that not many people have seen — the Greater Sage-Grouse.

Given the spectacular plumage of a male Sage-Grouse in display, why are these birds so hard to see? A quick look at a female Sage-Grouse tells you the girls are built for crypsis — well adapted to blending in with their environment. For most of the year male Sage-Grouse also play the hiding game, so unless scared into flight they may pass unnoticed.

Yet for a couple of months in winter and spring, males come into their traditional display grounds (called leks, from a Swedish word for “child’s play”) and put on one of the greatest shows on earth. These leks are often in fairly remote areas, and males typically attend them only in the early morning hours. Both of these reasons help explain why getting a look at this spectacle can be a bit of a challenge.

Greater Sage-Grouse / Photo by Alan Krakauer

The Sage-Grouse’s breeding clusters have captivated not only birders but evolutionary biologists as well. Unlike about 90 percent of birds, the males in lekking species don’t form a bond with their mate or provide any child care. Scientists are still trying to unravel some of the puzzles that leks represent:

• Why do males cluster together to display, rather than searching around for females, following females, or spacing themselves farther apart and defending larger territories like most other birds do?
• If males aren’t helping raise the kids, why are females so picky?
• What benefits do females get from choosing one male instead of another?
• And given that females often pick only a few among the many males on a lek, why do the “loser” males bother to stick around?

Lekking animals tend to be high on the charisma scale. Besides the spectacular Sage-Grouse and their cousins the Prairie Chickens and Sharp-Tailed Grouse, other lek-breeders include some of the most beautiful and acrobatic birds out there — birds of paradise, neotropical mannikins, peacocks, cock-of-the-rock, some hummingbirds, and Ruffs.

When we see a species in which males are larger or more colorful than females, we presume these differences are related to an evolutionary process called sexual selection, where one sex — often the males — competes either directly for access to females or indirectly by producing the best advertisement among the other males.…