Blog Posts Archive - Page 25 of 139 - Golden Gate Bird Alliance

Mount Sutro’s Bombardier Butterflies

By Liam O’Brien

They blast by incredibly fast, zipping and zagging every which way. No, I’m not talking about the annual visit of the Blue Angels for Fleet Week. I’m talking about our skipper butterflies. I remember wondering if I’d ever learn them, back when this butterfly mania took hold of me. Years of frustration, mainly because they all look so damn similar and don’t sit still long enough for a novice to study them. But then one day the clouds parted and I’d cracked their code.

Once thought of as halfway between butterflies and moths, skippers are impish, entertaining, and maddening, all at once. (How’s that for anthropomorphism?) Now that summer has officially arrived on Mount Sutro, I’m dedicating this blog post to the three most common ones at the summit and in our fair city.

We have a total of six skipper species scampering about San Francisco County. (Bet you didn’t know that.) They are the Fiery (Hylephila phyleus), the Umber (Poanes melane) and the Common Checkered (Pyrgus communis). Less common are the seasonal Sandhill (Polites sabuleti), the Woodland (Ochlodes sylvanoides) and the Rural—a population that I discovered breeding out on Yerba Buena Island in 2009.

Sandhill Skipper butterfly by Liam O’Brien

Woodland Skipper butterfly by Liam O’Brien

Skippers are a family of the order Lepidoptera (moths and butterflies) named the Hesperiidae. Being diurnal (day-flying), they are generally called butterflies. They were previously placed in a separate superfamily, Hesperiodea; however, most recent taxonomy places them in the superfamily Papilionoidea, the superfamily of butterflies, which taxonomically supports their description as butterflies. Did you get all of that?

The “skipper” name comes from their quick, darting flight habits. Most have antenna tips that are modified into narrow, hook-like projections. Moreover, skippers mostly lack the wing-coupling structure typical of moths. More than 3,500 species of skippers are recognized worldwide, with the greatest diversity in the neotropical regions of Central and South America.

Remember when you a kid and those little golden guys would blast about the family lawn? That was, and still is, the Fiery Skipper. I was somewhat surprised to see one up on Mount Sutro last season because one would not really consider it habitat. In San Francisco, it’s much more common on the Great Lawn. But there it was in August 2020, completing a trifecta of the ones we see the most in the city.…

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Contributing to a Breeding Bird Atlas

By Brandy Deminna Ford

Have you ever really looked at a Mourning Dove—its grayish blue crown, pale rosy breast, and shimmering iridescence punctuated by myriad black spots on the wings? Have you paused to notice the slight differences between a male and female pair or listened to a female’s low cooing call from a nest in a hollowed-out tree branch, continuing until a male approaches to replace her on the nest?
Mourning Doves by Sivaprasad R.L.
Busily birding, we often forget to look up from our species lists to really hear a familiar sound. Or catching a glimpse of a Mourning Dove in our periphery, we might not choose to take a closer look. But contributing to a breeding bird atlas isn’t just birding. It’s the chance to slow down, watch, and listen—and go from aspiring master birder to natural historian hopeful.

This breeding season, I have circled the Phyllis Ellman Loop Trail near Corte Madera a half dozen times, repeatedly walked along the public shore in Marin’s Paradise Cay, and been a rare visitor to the shoreline at Blackie’s Pasture in Tiburon—and I will be doing this for a little over a month more. It all began at the 2020 San Francisco Christmas Bird Count, when Atlas Coordinator Juan Garcia first introduced me to the idea of participating in the Marin County Breeding Bird Atlas.
Ring Mountain, in one of Brandy’s Breeding Bird Atlas survey areas. She saw a Vesper Sparrow there in April and a Rufous-crowned Sparrow in May. / Photo by Brandy Deminna Ford
The main purpose of a breeding bird atlas is to collect data that reflect the geographical distribution of breeding birds in an area. These data provide conservationists and other avian enthusiasts with the information they need to understand how birds interact with the surrounding environment over time and what changes occur to bird populations in specific areas. A bird atlas is much more than a list of species: It typically includes maps and illustrations as well as extensive narrative text.

This isn’t the first time a breeding bird atlas has been conducted in Marin County. During the breeding seasons of 1976, 1977, 1978, and 1982 organizers Bob Stewart and David Shuford assembled a group of dedicated volunteers to conduct the first bird atlas in western North America. After the initial bird atlas was completed in 1982, its findings were published in the Marin County Breeding Bird Atlas: a Distributional and Natural History of Coastal California Birds by David Shuford, a book that remains influential to this day.…

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Chow time for cormorant chicks

Photographer Rick Lewis, a Golden Gate Bird Alliance member, specializes in documenting the avian life near his Alameda home. Over the weekend he had a chance to watch young Double-crested Cormorants being fed by their parents in a nesting tree near a busy shopping center there. Here are two of the eagerly waiting chicks:

Double-crested Cormorants are the most numerous and widespread of our six North American cormorant species, and San Francisco Bay is one of their main nesting areas along the California coast. They lay an average of three or four eggs. The young don’t start flying until they’re five or six weeks old and they become fully independent around 10 weeks. In the meantime, someone needs to fetch them dinner, and it’s not DoorDash.

Adult male and female cormorants are indistinguishable, and they both feed the chicks through regurgitation. They catch and swallow fish until they’re full; then they return to the nest. The nestlings peck at a spot on their throat—the yellow gular pouch—which stimulates them to regurgitate the fish.

“The young Double-crested Cormorants need to coax the adult if they want food,” explained Rick Lewis. “It is only given after the proper ‘buttons’ are pushed repeatedly. Only then will the applicant be given entrance. It is an invasive process.”

Depending on how long it’s been since the fish were swallowed, they may have been digested into a slurry liquid or they may still be whole. Sometimes older nestlings remove an entire fish from the adult’s neck pouch.

The older or more aggressive nestlings get most access to food and have the best chance of surviving to adulthood. “Sometimes the other sibling simply waits its turn, other times it pesters both birds,” Lewis said. “The adults get tired after a while and turn away or move away entirely and take a nap.”

The feeding process can be messy! Ornithologists studying the diet of cormorants use the splattered remains of regurgitated meals to figure out what kinds of fish they’re eating. But bird barf isn’t just for feeding chicks. If threatened, both young and adult cormorants will regurgitate what they’ve eaten as a defense mechanism.

We’re fortunate to have so many Double-crested Cormorants around the Bay because of the environmental movement. The species faced a severe decline from the 1940s through the 1970s because of the pesticide DDT, which accumulated in the fish they ate and caused their eggshells to thin and break.…

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Dragonfly Detour

By Tara McIntire

Over the course of this past year, our lives changed forever For me, this has translated into a “world exposed” as I discovered the natural wonders of tiny spiders and pollinators, during endless hours in my garden during the early months of our shelter-in-place. I liken it to a forced road detour, along which you find a new bakery, coffee shop, or potential birding site (maybe even a rare bird!) you would not have discovered otherwise.

Rising at dark o’clock to drive endless miles to a birding hotspot had ceased. Long virtual work weeks left me exhausted and sleep became the new weekend priority. As the health restrictions eased, I finally ventured beyond the safe confines of my fenced yard, though a bit later in the day than before the pandemic. My favorite bird sites were too crowded with people for my comfort level, so I sought out locations where I could be alone, immersed in nature, and focused on birding.
Briones Regional Park, a perfect example of a people-free nature immersion zone. Photo by Tara McIntire.
On one particular excursion, I was trying to find seemingly non-existent birds, when something caught my eye (and ears). “Zooooooooooom!” I looked around, wondering if it were a hummingbird, but instead spotted a little blur whizzing about the meadow. It was a dragonfly!
A green darner (Anax junius) zooming through the sky. Photo by Tara McIntire.
I am endlessly curious, so it’s not as if I hadn’t ever noticed them. I’ve been absolutely mesmerized by dragonflies since my childhood, which is evident in my photographs taken over the years. Unfortunately, I’d been reserving space in my brain to store 10,000 species of birds! Surely, there was no room for these magnificent creatures; thus I had allowed time for appreciation and no more.

It wasn’t just the pandemic that caused me to take a longer look at dragonflies. Other sparks of connection and bits of information influenced my explorations into yet another new world. As I soon discovered, there was indeed room in the noggin for more!

After that first “zoooooooom” in early summer, I paid closer attention to these winged wonders and once again refocused my camera lens. Immediately I noted that dragonflies were ]everywhere! I found them teeming at ponds and riparian areas, high on dry ridge tops, and even in my urban backyard.
Variegated meadowhawk (Sympetrum corruptum) in the author’s yard.…

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Birdathon 2021: Soaring success

By Ilana DeBare

If Birdathon 2021 were a film, we’d say “it’s a wrap!”

Instead we’ll say, “it’s a rap-tor!”

Golden Gate Bird Alliance’s annual fundraiser came to a high-flying conclusion over the weekend, capping two months of innovative new events designed to carry on despite Covid.

Unable to hold our usual in-person Birdathon programs, our creative volunteers came up with three alternatives: a series of ten Virtual Field Trips via Zoom, a socially distanced Christmas-in-May Bird Count, and an online Birdathon Adventure Auction. They culminated with a Birdathon Virtual Celebration on Sunday night.

These new events were highly successful in all respects—number of participants, quality of the experiences, and funds raised. Here’s a flyover raptor’s-eye view of them all.
White-tailed Kite during the Oakland Christmas-in-May Bird Count, by Mark Rauzon
Virtual Field Trips

We sponsored ten Zoom “trips” that ranged from viewing Sage-Grouse in Lassen County to a pelagic journey to the Farallones. Over 400 people signed up and attended an average of two trips each. We raised $13,200, or more than $1,000 per trip.

Bonus: Video recordings of all the Virtual Field Trips are available, so you can watch any that you missed! View descriptions of the trips here. Then call our office at (510) 843-2222 to provide credit card payment of $15 per trip and get the link to the recording. The best time to call is on Mondays through Thursdays, from 10 a.m. to 1 p.m.

Christmas-in-May Bird Count

Over 140 people signed up for counts in Oakland and San Francisco that coincided with eBird’s Global Big Day on Saturday, May 8th. We managed to cover most of our regular Christmas Bird Count areas, and enjoyed sightings of breeding birds as well as balmy temperatures that aren’t available in December. Oakland count participants got to try out some new features—paperless reporting, using only eBird, plus new digital maps—that will prove useful in future Christmas Bird Counts.
Christmas-in-May Count at the Oakland Zoo / Photo courtesy of Mark Rauzon Barn Owl during Christmas-in-May Bird Count by David Assmann
Registration fees generated a total of $3,260; one generous member covered fees for people who found them a challenge. Special thanks to count compilers Dawn Lemoine and Viviana Wolinsky (Oakland) and David Assmann and Siobhan Ruck (San Francisco) for creating this successful new event from scratch.

Birdathon Adventure Auction

The online auction, which closed Sunday night, brought in more than $15,000 for Golden Gate Bird Alliance’s conservation and education programs!…

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