Hah! I also got tripped up this week in my over-eagerness to identify a bird! I was admittedly a little worried about posting a sighting on eBird of a species that is rare in this area at this time of year, and a gull at that! I should have known better. But I studied it so carefully in Sibley, went back and double checked, and was absolutely sure that it was a MEW GULL. I have a general rule never to identify a gull unless it’s a Heerman’s Gull whose bright red bill clearly distinguishes it from all other local gulls. Otherwise I simply count all gulls as ‘gull species’ and leave it at that. The interesting thing was that within 24 hours I got an official e-mail from your same local bird expert, Alex Rinkert, a volunteer regional data reviewer for eBird, that the gull photo I had posted was an immature CALIFORNIA GULL, not a Mew Gull. In his notification, he said that that an immature California Gull is ” distinguished from a Mew by the bill (longer and thicker) and the leg and feet color (pale bluish gray). Mews will have shorter, thinner bills that are not as blunt-tipped and their legs and feet as immatures will be pink.” In other words, if in doubt, look first for the big schnozzola! Cornell’s awesome eBird experiment in citizen science is really working. I humbly and dutifully corrected my e-bird posting. Thanks to Alex for his great work! The Mew Gulls can be expected to arrive sometime in October or November from their breeding grounds.
The most fun I had bird-watching this week was enjoying the antics of a CASPIAN TERN, first wheeling elegantly in broad circles overhead, flashing her handsome black cap and bright red beak, and repeating her inelegant raucous call. Then for some unfathomable reason, she decided to dive-bomb a solitary and hapless gull, floating innocently on the surface of the river, bothering no one as far as I could see. Finally, after about 5 minutes, the gull got fed up, screamed mightily at the tern, and took off. Then, to my surprise, the tern started to charge the water itself, just barely skimming the surface before quickly ascending and doing it again.
Why was the tern attacking a lone gull? Why did she skim the water over and over, leaving tiny ripples, but never diving or catching a fish? Time to check my online Bible, the Birds of North America. According to BNA, “Caspian Terns have the longest period of parental care of any tern; most immatures remain partly dependent on parents and continue to be fed by them for several months. In New Zealand, fledglings did not attain independence until about 9 mo of age. In Florida, an immature was observed in Feb following an adult and begging.” It also turns out that gulls are the most serious
competitor of terns for breeding sites. So maybe the tern was an immature one whose behavior was based on a long term grudge against gulls, as well as growing pains! Maybe she was strengthening her wings, or doing some fishing practice before heading out to deeper water in the ocean for some serious fishing.
In the three years that I have been observing this bird-rich urban river, I have never seen a COOPER’S HAWK – although others often post sightings. I think one of these hawks finally took umbrage with my obliviousness to his presence and decided to make it impossible for me to ignore him anymore. He flew just a few feet in front of my nose! Startled, I actually jumped back while still managing to get a good close up view of his long tail and many bands. “Now – don’t forget to mention me in your blog,” he seemed to be saying.
Almost all the swallows have left the river, presumably heading south for the winter. I felt sorry for two CLIFF SWALLOWS still tending two visible babies in a mud nest under the Riverside Bridge. It must feel lonely to have such a late brood and see your flock leave without you.
I happily received my new camera – the same Lumix Panasonic brand I have become attached to. I have also finally made the serious shift from’ automatic ‘to ‘aperture priority’ with some pleasing results. I am able to capture bird movements a little better, like this photo of a SNOWY EGRET.
The only downer of my wonderful walk
was the slightly offensive monument that the Rotary Club erected to itself for planting native mugwort, native rose and native monkey flower in a small parklet near the San Lorenzo Park footbridge. Can we now expect these ugly monuments in every parklet along the river, providing some pretty cheap advertising in exchange for a few native plants?
Ironically, the mugwort plants in the photo are the same plants which exist in abundance
directly across the Riverwalk from the Parklet, freely growing and scheduled to be cut down by Public Works starting in mid-August. As you know, I have written a letter to Public Works requesting that the City consider hand-cutting at least some areas of the inner levee in order to protect the native plalnts that already exist there. I have also asked that a biologist tag the native plants to be saved. Currently they just get mowed down – collateral damage of tree removal.
What a muddle life is – natural beauty, animal antics and human folly.
May all species survive this together.