Blog Posts Archive - Page 26 of 137 - Golden Gate Bird Alliance

Osprey Cam launches fifth nesting season

By Craig Griffeath

A little over seventy-five years ago, a visitor to the naval shipyards at Richmond’s Point Potrero would have encountered an impressive bustle of activity, with thousands of tough, dedicated “Rosie the Riveters” putting in long days on the heavy equipment at the yard in order to provide for their families. Today, at the historic Naval Shipyard No. 3, you can still see the last of the huge Whirley Cranes that once built the WWII Victory Ships there. And there’s still one tough, smart, dedicated Rosie there too, working hard atop the crane to raise her children. She’s an Osprey, and she’s also an Internet star whose fans are at the forefront of research into San Francisco Bay’s Osprey population.

Rosie on the Whirley Crane last year, in March 2020

Just a few weeks ago, on February 18, Rosie completed her annual migration and returned to the Point Potrero Whirley Crane to reunite with her endearingly quirky mate Richmond, an event greeted with jubilation by the thousands of fans who follow the couple’s adventures on the Golden Gate Bird Alliance Osprey Cam at sfbayospreys.org. Fierce and charismatic in equal measure, Rosie and Richmond now command their own Facebook page, their own YouTube channel, and a remarkable network of volunteers and supporters who make up their broader human family.

Richmond is one of just a few Ospreys around the Bay who don’t migrate in the fall. Instead he stays close to his namesake town for carefree winters of fishing on the Bay, paying occasional visits to the nest site while awaiting his mate’s return. This year’s reunion marked the start of Rosie and Richmond’s fifth season of nesting together at the Whirley Crane. The pair have fledged ten chicks since 2017, all banded for identification, and at least two of those banded offspring have been seen around the Bay after their own first return migrations.

Rosie (left) and Richmond, together again, on March 4, 2021. You can identify Rosie by her speckled “necklace.”

Richmond with his wings up and Rosie on the cable, March 13, 2021

Rosie and Richmond’s success is emblematic of the larger success their species has enjoyed in recent decades. Among the most widely distributed of all bird species, Ospreys are voracious fishers who historically built their nests in the tops of trees next to water. In the 20th century, Ospreys faced existential threats from habitat reduction and pesticides such as DDT, but they’ve made a strong global recovery since the 1980s.

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Sage-Grouse Courtship Season

Editor’s note: On Wednesday, March 24, Bruce Mast will be leading a Virtual Field Trip via Zoom to see Greater Sage-Grouse courtship dances, as well as Sage Thrasher and Sagebrush Sparrow—a Sage Trifecta. As a preview, we’re reprinting Bruce’s 2019 blog post about his annual Sage-Grouse trip to Lassen County. You’re invited to join us for his March 24th Zoom presentation, which is part of our annual Birdathon fundraising month: Details and registration at goldengatebirdalliance.org/birdathon_trips/43301/.

By Bruce Mast

The eastern sky was just beginning to glow pink. We were cold. It was early spring in the eastern Sierras and we were cold. And under-caffeinated. We had been up since 4 a.m., bundling into our down and fleece, driving since 5 a.m. past the High Desert State Prison, and then trudging up the flank of Shaffer Mountain to shiver expectantly on the side of a rutted jeep road. We were 20 hardy souls from Golden Gate Bird Alliance, under the veteran leadership of Dave Quady. Why had we journeyed northeast to Susanville to visit such a desolate place? The answer came soon enough.

Grouse watching at Shaffer Lek

The answer came quietly—low, muffled plopping sounds from the north. A binocular scan revealed an expanse of yellow, lava-strewn grass interrupting the sagebrush sea. But some of the rocks were moving! As morning light spread over the landscape, the tableau came into focus. Greater Sage-Grouse, those enigmatic denizens of Basin and Range sagebrush country, were gathering for their annual lekking ritual. Wikipedia tells us that a lek is an aggregation of male animals gathered to engage in competitive displays to entice visiting females, which are surveying prospective mates. The term derives from the Swedish “lek”, a noun that typically translates as “play”. The term was originally used for Black Grouse (Swedish: “orrlek”) and for Western Capercaillie (Swedish: “tjäderlek”).

Sage Grouse, Shaffer Lek, Lassen Co., March 19, 2016

On this morning, multiple male Sage-Grouse strutted regally, their spiky tails fanned, white feathering on the sides and back of their necks forming a royal ruff. Large air sacs on their breasts suggested avian bagpipes. Scope views revealed large yellow bare patches on their breasts, a yellow fleshy comb above the eye, and wispy filoplumes extending from their nape.

The dominant males held court in the center of the lek, challenging newcomers for status and position. Most interactions involved choreographed strutting and posturing but occasionally a wing fight was required to put a young male in his place.…

Wintering Shorebirds on San Francisco Bay

By Maureen Lahiff

Spring is almost here, but there’s still time to enjoy the shorebirds that are here for winter R&R. Many of the species that winter in large numbers on San Francisco Bay have come a long way on their fall migration. They spend the summer nesting in a wide diversity of habitats, from the high Arctic and sub-Arctic, to the forests of Alaska and across northern Canada, and across the Great Basin and the Great Plains.

Shorebirds are drawn here for the winter by our climate; our shorelines bordered by marsh plants; and the large variety of invertebrates and small shellfish that make their homes in the mudflats and intertidal zones bordering the Bay, thriving in the Bay’s mix of salt and fresh water, referred to as “brackish.”

The miracle of wetlands

Although we’ve lost 90% of the wetlands that ringed the Bay before 1850, what’s left still provides a smorgasbord for shorebirds. The food chain is driven by microscopic organisms, phytoplankton and zooplankton, which are consumed by invertebrates and tiny fish.

Conservation efforts by a number of organizations including Golden Gate Bird Alliance have led to improved habitat for shorebirds. At the same time, restoring wetlands provides a buffer against sea level rise.

What is a shorebird?

Not all birds at the shore are shorebirds, and not all shorebirds are found close to water. The essential characteristic of shorebirds is that they feed by picking and probing with their bills. Some hunt by sight, while others with longer bills probe in the mud and the bay floor, hunting by touch and smell.

When you see a number of shorebirds feeding together, notice how their different sizes and bill lengths allow them to use slightly different niches in the same habitat, so that they are not directly competing for the same food resources.

Shorebirds are also notable for their long legs: The Brits call them “waders”!

Some great birds to get you started

Shorebird watching is rewarding for beginning birders and children, as many species are easy to see when feeding along the shoreline. Unless disturbed, they walk or wade while searching for food, so you can get a leisurely look. It’s helpful to have binoculars, but you don’t necessarily need a spotting scope. If you don’t want to carry a field guide, consider the “Beach and on the Bay ” foldout guide in John Muir Laws’s The Laws Pocket Guide Set: San Francisco Bay Area.…

Reflecting On An Unusual SF Christmas Bird Count

By David Assmann

The 2020 San Francisco Christmas Bird Count nearly didn’t happen due to the pandemic. Fortunately, San Francisco birders adapted to the challenge. Although we had to follow strict new guidelines, this winter’s count turned out to be one of the best in decades. 103 socially distanced counters ended up tallying more than 68,000 birds by the end of the day on December 29th – the highest tally in more than 30 years. This was also up about 35% from last year’s total – which is even more impressive considering we had a lot fewer counters, and we didn’t have access to all the areas we are normally able to access.

In addition to solo bird counting, this was also the year of modernization. We transitioned away from paper tallies to using eBird for data collection and compiling. A total of 269 eBird lists were submitted. Counters were also able to accurately pinpoint the boundaries of each area, thanks to GIS maps created by William Wiskes. And the traditional count dinner was replaced with a well attended Zoom countdown.

By the time count week was over, the species tally stood at 189 – only two species fewer than last year’s record 191 species. There were lots of rare species – 29 in all. Almost every area (14 of 17) had one or more rare species.

The best bird of the count was a Black Storm-Petrel, spotted by Josiah Clark, flying 100 yards offshore at Crissy Field. A Storm-Petrel has never before been seen on a San Francisco Christmas Bird Count, and Black Storm-Petrels have only been seen five times in the 120-year history of the count in California. An Ancient Murrelet seen from Ocean Beach was the other seabird of note.

Ancient Murrelet by Eric Ellingson

Overall duck numbers were similar to previous years, with increases in American Wigeons and Northern Shovelers but declines in other species. We missed White-Winged Scoter for the first time ever, which is remarkable considering that in 1990, there were more than 1,200 seen. Scaup numbers dropped to 611 (down almost two-thirds from last year). We had two Redheads on the count (Crystal Springs), as well as a Long-Tailed Duck (Land’s End). A Harlequin Duck (Cliff House) was seen during count week.

The highest number for a single species was for Double-Crested Cormorant, with 5,303 reported, with almost all of these viewed on the Bay from the South of Market area.…

Plants for Birds: It’s Not Too Late to Dig In!

By Noreen Weeden

Planting season in the San Francisco Bay Area is late fall through winter. With a forecast of rain ahead, it is not too late to get some beautiful native plants in the ground to benefit our birds. You may have heard that Plants for Birds is an exciting partnership of GGBA and the Yerba Buena chapter of the California Native Plant Society (CNPS). This season we are promoting a native tree, vine, bush and groundcover. Each of these plants provide food for butterflies and birds.

Over one third of the birds in the US eat insects. Doug Tallamy, entomologist and author, has worked with student researchers conducting studies on the insects which eat or lay eggs on plants which are then consumed by birds. In fascinating co-evolutionary strategies most insects require specific plants. Many exotic plants and plants sold as pest free have chemicals in their tissues which repel insects.

Early last year I spoke with Kathy Kramer of Bringing Back the Natives fame. She and her husband Michael May had taken Tallamy’s research and looked at west coast plant – insect associations. Taking this further was a chance to evaluate San Francisco plant species. Using that data, I took the San Francisco plant list and looked at CalScape- a CNPS plant resource. After analyzing these a tree, vine, bush and groundcover were selected for the program which attract local birds and butterflies. The GGBA San Francisco Conservation Committee then went to work to make it local by contacting local nurseries to see if they would be interested in selling these plants. Qiting “Tina” Cai, an intern with CNPS, prepared graphics to promote these plants.

This season’s four fabulous featured plants:

Coast Red-flowering Currant Ribes sanguineum var. glutinosum is an awesome plant. It blooms in the winter and is attractive to Anna’s Hummingbirds and the Satyr Comma and Ceanothus Silkmoth.

Coast Red-flowering Currant by Noreen Weeden

Anna’s Hummingbird by Noreen Weeden

Coffeeberry Frangula californica a bush with berries which Cedar Waxwing and other birds consume and the Gray Hairstreak and Pale Swallowtail Butterflies depend upon.

Coffeeberry by Neal Kramer

Cedar Waxwings by Noreen Weeden

California Honeysuckle Lonicera hispidula is a native vine with pink flowers appeal to Anna’s and Allen’s Hummingbirds and Chestnut-backed Chickadee as well as the Variable Checkerspot butterfly.

California Honeysuckle by Margo Bors

Allen’s Hummingbird by Noreen Weeden

Beach Strawberry Fragaria chiloensis was the selected groundcover. …