Field Journal – Mill Valley/Mt. Tam
Date and Location:
11/1/23 – Mill Valley/Mt. Tamalpais, Marin County, CA
Site Description and Conditions:
Warming to the mid 60s; Early fog yielding to full sun; slight breeze. We stopped at two main locations along this trip: the Mill Valley Air Force Station and Mt. Tamalpais State Park with a side excursion to “The Pole” nearby giving us beautiful views. Upon arrival temperatures were much cooler, with somewhat damp conditions, but quickly warmed with sunny skies. Lower elevations were covered in moderate fog early. Mill Valley AFS gave us good views of some open coniferous forest edge habitats with some classic scrub and expansive looks of the Valley below us, allowing for excellent observation of birds in flight from a high elevation. At the second site we were able to see more panoramic views of Stinson Beach below us from a high elevation, with more forest edge habitats including various trees that were being utilized by woodpeckers, many with bored holes present; one open grassy area as well.
Narrative:
Upon arrival we were able to view many perching birds, including high numbers of the Pine Siskin and Dark-eyed Junco, before observing many Scrub-Jays and Stellar’s Jays, easily seen under full sun with their striking blue, many flying with food across the valley below. A few Red-tailed Hawks flew overhead; this area and Mt. Tam seem to be popular with woodpeckers…Acorn Woodpeckers were seen at both locations along with one Hairy Woodpecker. It was very interesting to view the ways in which these species bore into trees up close. At Mill Valley AFS we saw two Merlin, striking falcons making a rare appearance for the class. Our second stop yielded some raptors flying overhead including the Northern Harrier and Red-tailed Hawk, along with a large group of Band-tailed Pigeons flying overhead.
Species Account: Merlin – Falco columbarius
A falcon in the family Falconidae, one of the smaller falcons measuring roughly 9-13 inches in length with a wingspan from 20-30 inches. Can be found in the types of habitats on this trip, particularly open forests and areas near the coast where shorebirds are found. Dark on the back with a paler chest, some yellow around the eyes and on the bill. Females are slightly larger than males, and many in North America have adjusted to urban life to the point where many are forgoing migration.
Home Time – Sutro Baths, Lover’s Ln.
On Nov. 12 and Nov. 13 I spent time birding at two separate locations; Sutro Baths on the 12th and Lover’s Lane in the Presidio the following day. Instead of returning to the Lands End trail I decided to take a look at the adjacent Sutro Baths expecting to see some gulls, shorebirds, and/or waterfowl. Upon arriving I was greeted by multiple gulls: Bonaparte’s and the Ring-billed, along with numerous Brandt’s and Double-crested Cormorants, a Great Egret, and a Great Blue Heron. Notably, the ruins were covered in guano…Additional common species seen included multiple Dark-eyed Juncos and Chestnut-backed Chickadees, presumably making their way down the hills from Lands End, along with some swifts overhead.
https://ebird.org/checklist/S156153115
The next day I checked out Lover’s Lane in the southwest corner of the Presidio; notable for very high Eucalyptus globulus along the route. Here, I was expecting to see some common species we had already seen along with some less common ones; I walked along the route both in the curving forested area and along the edge of the trees, adjacent to some old military housing with a better view of flying birds above. During my personal birding in November I was able to get multiple Red-shouldered Hawks in the area, including at this location. Common species observed included the Dark-eyed Junco, Black Phoebe, and House Finch, among others; this was a slightly underwhelming trip.
https://ebird.org/checklist/S156153624
Merlin Meditations – Lover’s Ln.
On the 13th I spent time walking around this area and turned on Merlin for the duration of a hike through the Presidio, without observing the entire time. I paid attention to the very loud call of the Red-shouldered Hawk and the American Crow, taking time to differentiate between the Crow and Raven. Vocalizations were more pronounced with elevation from east to west; the higher up I got into forested areas the more species Merlin was able to pick up.