Corona Hill

Corona Hill

By Dominik Mosur

The City of San Francisco is sprinkled with an array of small parks ideal for a birder on a time budget. One of my favorites, especially on a warm, east wind day in Fall, is Corona Hill.

Standing approximately 540 degrees  above current sea level,  Corona Hill is a lone outcrop on the northeast flank of the San Miguel Hills. It first appears in written history as the site of a brick factory at the turn of the 20th century. The brick makers used dynamite to rip the hill apart to extract the symmetrical layers of chert, a fine-grained sedimentary rock, that makes up much of the bedrock in this part of San Francisco. As the city rushed to develop the last remnant scraps of open space at the end of the 1940s, a parks superintendent named Josephine Randall envisioned a public destination on top of this hill. The result was a park and museum juxtaposed against the residential neighborhoods already sprawled over most of the other peaks of the growing city. Today 100,000 people visit Corona Heights Park and the Randall Museum each year.

Fall Migration

September through November, when the weather heats up, migrants move through the Central California Coast. Big numbers of Violet-green Swallows and Vaux’s Swifts and in some years Band-tailed Pigeons, Pine Siskins and other more irruptive species. Over twenty species of raptors have been noted passing the hill in the past 15 years. The bulk of these are turkey vultures, accipiters and red-tails but rarer species like kites, harriers, and kestrels pass over regularly when conditions are prime, as do the rarer migrating hawks like Broad-winged and Ferruginous Hawks, and more rarely Rough-legged and Swainson’s. Depending on the strength of the east winds the previous night, skeins of White-fronts or Cackling geese may pass over into midday as they redirect back to the valley. The hot east wind days can also blow in surprises like Lewis’s Woodpecker, Rock Wren and Townsend’s Solitaire.

As the seasons pass into winter, birding Corona Hill slows down considerably. Other than the occasional late migrant raptor or flock of misdirected water fowl, few new arrivals are noted after December until the early spring migrants begin their trek back north in March. However, Northern Saw-whet Owl and Burrowing Owl have both shown up in late Fall /early winter. Spring migration can be productive on days when many birds are moving through on the coast.…

California’s 30×30 Goal

California’s 30×30 Goal

By Whitney Grover

What is 30×30?

In 2020 Governor Newsom signed executive order N-82-20, committing to protect 30% of California’s land and coastal waters by 2030. In September of 2022 the state legislature passed, and Newsom signed into law, AB 2278 (sponsored by Assemblymember Ash Kalra), directing the California Natural Resources Agency to implement the program and report on its progress. The heart of the initiative is to prioritize nature based solutions to fight against climate change and protect California’s incredible biodiversity as it faces significant threats.

The California Natural Resources Agency formed the 30×30 Partnership and hosted a kickoff meeting in Sacramento in early October. Legislators, agencies, land managers, indigenous communities, scientists, and nature organizations like Golden Gate Bird Alliance came together to get started and learn how best to contribute.

Where are we now?

So far the state has roughly 24% of terrestrial areas and 16% of marine areas conserved. Check out the Conserved Areas Explorer to dive in and see which areas near you are already protected. Below is a screenshot of Golden Gate Bird Alliance’s terrestrial territory, the green areas are considered protected and included in the 24% assessment.

Golden Gate Bird Alliance’s terrestrial territory. Photo from 30×30 Conserved Areas Explorer

How do we get there?

In April of 2022, the California Natural Resources Agency published 30×30 Pathways, a document outlining specific actions and strategies, including a prioritization of 10 pathways to achieve the 30% preservation goal. But the real work in protecting additional land and water will happen regionally, in our local areas.

Here in the Bay Area we have unique challenges. You can read more about our current land use statistics and focus areas in the regional report. The designated San Francisco Bay Area Region encompasses 7.5 million people in 6,400 square miles, which is roughly 20% of the state’s entire human population in 4% of the state’s area!

Despite the urban and suburban development here, and this will come as no surprise to birders and naturalists, the majority of our area is also given a high biodiversity rating by the state. The Statewide biodiversity rating is determined by the California Department of Fish and Wildlife’s Areas of Conservation Emphasis which considers native species richness, rare species richness, and irreplaceability.

30×30 Appendix A

No one knows the Bay Area, its natural resources, and open spaces better than Golden Gate Bird Alliance members. 30×30 is prioritizing protection of areas already adjacent to protected areas, or areas that provide important corridors to wildlife.…

I Heard It Through The Vine: Butterflies on Mount Sutro

I Heard It Through The Vine: Butterflies on Mount Sutro

By Liam O’Brien

     People always come to a butterfly walk slightly fearful. I find this strange considering how much joy these bugs seem to give us all. But it is true primarily because many aren’t sure of their butterfly species and the butterflies fly around so damn fast how could anyone really identify them? (Fascinatingly enough this is how I feel on a bird walk.) The group always seems to be in awe when I throw out the known factoid that if one sticks to it long enough, and gives themselves many years to get it wrong, a person can not only identify a butterfly on the wing but they’ll be able to tell it’s sex then as well. I try to reassure a group before the walk that everyone can add to the day with their own set of eyes. ” If you see one flying that way and the group is looking the other way say, ‘There’s one!’ and everyone will look that way and hopefully I can identify it. But an interesting thing happened this season: it turns out I don’t really even need to be there.

     On the morning of April 7th, 2022 Kelly Dodge, an employee of the Sutro Stewards was leading a group of volunteers up to the summit of Sutro. The following is an excerpt from an email Kelly recently sent me: ” We were at the large, main meadow right off from where the pavement ends from Nike Road. I saw a black and blue (this becomes important – the blue part) butterfly drop down from high above and into the meadow, it then flew towards the North Ridge Trailhead at the summit. Unfortunately it was moving too fast ( second clue ) to get a photo. On the same day Morgan told me he saw a Pipevine Swallowtail down by the Surge Lot around 1 p.m. Same individual?” The lawyer in me knew immediately we had a strong circumstantial case.

Male Pipeline Swallowtail, (note the gunmetal blue on hindwing) by Liam O’Brien

     In another email Ildyko Polony, the Executive Director of the Sutro Stewards, wrote: ” I saw at least one after Kelly’s flying around sometime in the late spring/early summer. It may have been more than one individual. It was up at the summit. Bridget and I were sitting and I saw this butterfly flying in and out of the acacia thicket and in the fenced off area where the silvery lupine grows.…

Behind a Winning Shot

Behind a Winning Shot

By Alan Krakauer

Female Greater Sage-Grouse, winner of the 2022 “Female Bird” category

By now you may have seen the winners of the 2022 Audubon Photography Awards. Given the ever-expanding ranks of excellent bird photographers, I had no expectation of winning anything when I submitted three photos this spring. I had entered a few times in the past, and with the exception of a photo of roosting Marbled Godwits at Arrowhead Marsh that made the Top 100 in 2019, I’d not had any luck. I was just happy my entry fees were going to a great organization. You can imagine my shock when a representative from the National Audubon Society called to tell me my photo of a Greater Greater Sage-Grouse hen took home the “Female Bird” prize!

The story of the shot itself is doubtlessly similar to many other photographs recognized by Audubon through the years. Like most, it’s a variation of ‘photographer gets up early, waits patiently in unpleasant weather for birds to appear, magic happens.’

In my case, the magic happened in central Wyoming. My day started well before sunrise carefully navigating a snow-covered gravel track into sagebrush country. Parking on the shoulder in a remote valley, I switched on my headlamp, hoisted my backpack and thermos of coffee and trudged through several inches of snow. Eventually I reached my destination and my headlamp beam swept across the photography blind that would be my home for the next several hours. The fabric blind was already staked in place so it was just a matter of popping it up (not always easy when the pieces were frozen!), opening a couple of view flaps, and waiting in the pre-dawn chill for the first Greater Sage-Grouse to arrive.

Pop-up blind in Greater Sage-Grouse country. Photo is from a different day and location

In the spring, Greater Sage-Grouse and other prairie grouse congregate on traditional display grounds called leks, a term that is used both for the groups of animals and the spot of land they use. These leks are extremely vulnerable to disturbance – one golden eagle zipping by or person walking up could scare all the birds away for the day and repeated disruptions could cause them to abandon the area completely. What is a photographer to do? Temporary blinds are small fabric tents that can hide wildlife watchers and their gear in view of a lek or other area of interest.…