August Recap
In case you missed it you can find last month's newsletter here: august newsletter
August bird walk
In August we birded at Heron's Head Park.
I made a checklist.
One of our birders also reported a Glaucous-winged Gull (Larus glaucescens) but it counted as a rare or uncommon sighting and I couldn't recall enough details to include in the submission so I left it off ebird.
Daniel and May+Chad took a lot of cool photos and shared them on the partiful. I'm including some of the highlights below. Also sorry if the quality is degraded I think partiful runs them through the washer on upload.. :0
First up Daniel took a ton of nice shots:
Thank you to everyone who came out and thank you to Ronnie, Audrey, Daniel, May, and Chad for sharing the photos!
September Bird Walk
This month we're going to hit up another classic: north lake in GGP
The birding walk will be on the saturday morning of september 19th.
Head to the partiful link
to rsvp.
Spotlight Bird: Forster's tern (Sterna forsteri)
Watching the constant diving from the terns was the highlight of last month's walk at Heron's Head so figured they'd make a good bird of the month.
Fun Forster's tern Facts:
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From a quick glance at the range map above it is pretty colorful around the bay and the bordering regions.
You can see some yellow (migration), blue (nonbreeding), orange (breeding), and if you zoom in enough you can see
the purple (year-round) in sf/bay. Below is the bar chart for sf:
ebird weekly bar chart for sf - Terns are in the subfamily Sterninae and the family Laridae which includes gulls. They used to be in their own family but fairly recently, starting about 30 years ago and more formally accepted a little under 20 years ago, they were brought in with the gulls. The history is kind of interesting - apparently they looked into the DNA sequences and stuff to evaluate the evolutionary history between the species and that's how they decided to bring the tern family into the gull family. I'm pretty illiterate with this type of science, but the Laridae wiki and this paper have some cool reading if you want to dive deeper.
- They are an occasional vagrant in europe. Here is a mention of one showing up in England this last spring.
- I was looking for research papers on these guys and came across this one titled Oxidative stress response of Forster's terns (Sterna forsteri) and Caspian terns (Hydroprogne caspia) to mercury and selenium bioaccumulation in liver, kidney, and brain. Basically the terns in the SF bay are impacted by the mercury levels. This lead me down the rabbit hole of why there is so much mercury in the bay and apparently we have the gold rush to thank. This is a pretty interesting wiki on the subject if you want to learn more.
- They are very accurate fishermen. On our walk they were flying up to maybe about 25 or so feet and then doing shallow plunge-dives and more often than not they were coming up with small fish.
Member Submissions
Thank you to everyone who sent me photos of the birds they saw!
To lead us off Alaina birded up in Alaska and saw a ptarmigan.
Next up Taylor hit up crissy field marsh and saw a ton more terns. These ones were elegants (Thalasseus elegans) and commons (Sterna hirundo)
Adam lived out every birders dream and hit SE Arizona. He saw a ton so only including some highlights below
Dom had some nice sightings down in Santa Barbara
Jeff set up a feeder cam and a hummingbird feeder and his backyard birding in the east bay is kicking off nicely.
George finshed up his Italy birding earlier in the month
Gus and Anjali birded up in seattle
Aarsh birded down in the south bay
Katlyn went to the SF Zoo
Janet ran up twin peaks and saw a hawk
I took a few bird pics this month as well. The scoters were at candlestick and the rest are from a trip to ocean beach looking for the ruddy turnstone which I did not see :/
Closeout
That's all; happy birding