In French, it is known as the Gray-mantled Gull, Goéland à manteau ardoisé. In Spanish, it is the Kamchatka Gull, Gaviota de Kamchatka. In English, we call it the Slaty-backed Gull. For those of us living in California’s San Joaquin Valley, we call it the “Extremely Rare Gull”. So rare in fact, that it has only ever been seen once before in the entire San Joaquin Valley, and never in Stanislaus County.
SLATY-BACKED GULL WORLDWIDE DISTRIBUTION
The Slaty-backed Gull is a regular breeding bird along the coastal areas of the Western Pacific from North Korea, Russia (including the Kamchatka Peninsula) and just a tiny portion of the Seward Peninsula in north Alaska. It spends the winter mostly in the coastal areas of Japan, Korea and the Yellow Sea area of China and can show up unexpectedly in random locations in the US, from California to Texas. As of February 18th of this year, it can now be counted as a visitor to Stanislaus County.

STANISLAUS COUNTY CHECK IN
If it were a FaceBook-using gull, on February 18th of this past week, it could have done a Check In from the Recology Grover Environmental Products facility north of the Westley Rest Area.

Or more precisely, hanging out with 6,000 of its Facebook friends along the California Aqueduct next to the Recology Facility.
A LITTLE CALIFORNIA HISTORY
According to the records from the California Bird Records Committee data base, the first ever accepted record for the state dates back to February 5, 1995 with the second ever record coming six years later in 2001. Over the past decade there have been a total of 36 accepted sightings. The increase in records could be due to an actual rise in the numbers of birds straying over here from Asia, or it could be that birders are more informed and knowledgeable on the identification of the bird. I suspect that it is a combination of both factors.

A FIRST RECORD FOR THE SAN JOAQUIN VALLEY
In February of last year, David Yee (aka birdmanyee) spotted and carefully recorded the first Slaty-backed Gull for the entire San Joaquin Valley, from Bakersfield to the Delta. The bird he recorded was found at the gravel pits along Koster Rd, San Joaquin County, barely a mile north of the Recology Facility on Gaffery Rd, Stanislaus County.
A DREAM BECOME REALITY
In an email communication with Eric Caine on January 29 of this year, I stated, “I’m going to find a Slaty-backed gull in February and I’ll call you when I find it!” Little did I know that less than 3 weeks later, this prediction would turn to fact. I got up early as usual on President’s Day and checked my email, looking for a reason to get out of house cleaning. I soon discovered that birdmanyee had reported another Slaty-backed Gull at the same spot, a year later, as the first record. Knowing that the gulls like to move between the gravel pond on Koster Rd to the canal along the Recology Facility, I jumped in my car and drove, as quickly as legally possible, out to the Recology canal. I have made this trip many times in the past only to find the canal completely empty. As I crossed the bridge over the canal, my adrenaline kicked in as I saw at least 5,000 plus gulls along both sides of the canal. The words came to mind, “Be careful what you wish for!”
SEARCHING FOR A NEEDLE IN A HAYSTACK
So, how hard is it to find and identify correctly, a Slaty-backed Gull? For reference, the same CBRC database of Slaty-backed Gull records over the past decade, also shows that 40% of submitted sightings were not accepted due to the difficulty of identification. There have been 16 different species of gulls documented in Stanislaus County, 8 of which are in the same bird family, Larus. Of these 8 similar shaped and sized species, for adult birds, identification can be narrowed down by a quick look at feet and back color. Adult Larus gulls have a mostly solid mantle ranging from medium gray to dark gray to black. In the photo below the ranges are pretty visible from the medium gray-backed gulls in the middle to the black-backed gull on the upper right corner. In the case of the Slaty-backed Gull in this post, we are looking for one like that black-backed gull.

Larus Gulls
So as I scan the flock, I have a search cue set for birds with an obvious black back. The challenge is that the flock is in constant motion. Birds come and go and on occasion, the entire flock will burst upwards in unison, circle around and land back on the canal bank or gentle land and float in the water, completely mixing up which birds I had already scanned and which ones I hadn’t.

Gulls in Motion
I made one pass though the entire flock, taking about 45 minutes to do so. I turned around and started back. During my first pass, I noted at least 8 to 10 Western Gulls, which have the black(ish) back. They are actually somewhat rare in the county, but can be found here if the gull flock is large enough. I made my way slowly back down the canal, gently causing the birds to mostly just peel off a couple at a time and then fly behind the car and land. Most of them just walked out of the way. I was going very slowly and they practically ignored me.

So many Gulls
I was almost completely through the end of the flock again when I noticed a 1st year Glaucous Gull on the other side of the canal. That is another rare species, about as uncommon as the Western Gulls, but not an extreme rarity. I frequently glanced in my side-view mirror to make sure another vehicle wasn’t coming so I could focus on the gull across the canal. I noticed there were two “black-backed” gulls on the berm behind me. I thought to myself, “after I get shots of this Glaucous Gull, I can shoot the two Westerns behind me”.

Glaucous Gull – 1st cycle
As a photographer, you can never get too many shots of a rare gull, so after shooting 2 dozen shots of the Glaucous Gull across the canal, I got out of my car slowly, so I could get some shots of the two Western Gulls. I zoomed in and took a shot of the closest Western that was right next to a common Herring Gull, with the other “Western” gull behind them both.

Herring and Western Gulls
As I focused on the front Western, I took a couple of shots and then decided to try and get all three birds in focus. It was the next focus in my viewfinder that knocked my socks off! The second “Western” gull was clearly NOT a Western Gull, it was THE Slaty-backed Gull.

Slaty-backed Gull – Adult
Suddenly, I couldn’t hold my camera straight, my hands started to shake and my heart beat went off the charts. But I knew that I had to get about a million shots of this bird AND I has to get it in flight. The absolute positive ID of this bird is cemented by the documentation of a series of white pearl spots along the primary flight feathers. The pattern visible on the extended wing shows a terminal white spot, a black spot and a second white spot above the black one. These spots are not present on the similar looking Western Gulls.

Slaty-backed Gull – Adult
Pretty soon, I calmed down because the bird simply could not be bothered by my presence. I slowly started walking towards it, click, click, clicking as I went. Not wanting to scare the poor thing, I just stood there clicking more shots. I even went to video mode and shot about 4 minutes of it just standing there doing nothing. At one point, part of the flock flew up and moved back about 40 feet, but the Slaty-backed just stood there. At this point, the gull was a mere 13 feet away and just watching me.

Slaty-backed Gull – Adult
Suddenly once again, the gull flock took off, and this time the Slaty-backed Gull went with them. I tried to keep up with it amongst the swirling cloud of gulls, but most shots were either blurred or partially blocked by other gulls.

Slaty-backed Gull – In Flight
AND NOW, THE REST OF THE STORY
After I had calmed down and was certain I had some decent photos, I reached out to David Yee to see if this gull had the same appearance as the one he had the day before. I sent two snapshots from my camera’s viewfinder via email and he promptly responded that it looked like it might be the same bird. I then texted a few local birders and sent Eric Caine an email with the information. He responded that he was running out the door and would get there as soon as possible. Notifications were then also sent to the local bird groups.
Queue the music… I Ran (So Far Away)”
Unfortunately, by the time Eric got out to me at the canal, THE gull was awol.

Gull flock in the air
When I got home, I proceeded to go through the 750 images and 5 videos I had taken and came up with a few shareable images. I then jumped online to social media and I posted on the North American Gulls and the California Rare Bird Facebook Groups. I had over 6,000 hits on my SmugMug site the first couple of days after I had posted them. As of today (2/22/19), while it has been seen at the Koster Rd Pond in San Joaquin County, no one else has seen the gull in Stanislaus County. Queue the music…”I Ran (So Far Away)”
Other Birds Photographed at Recology

Herring Gull with Oiled Feathers

Iceland Gull – 1st Cycle

Iceland Gull – 1st Cycle

Glaucous-winged Gull – 1st Cycle

California Gull – Adult

Western Gull – Adult

Iceland Gull and Herring Gull – Adults

Cattle Egret
Jimmy, I tried to find sea gull in my Sibley index. Why isn’t it in there?
LikeLiked by 1 person
Well, sometimes they’re not seen over the sea. If you see them in the bay area, they’re called bagels…
LikeLike
I thoroughly enjoyed this story. Thanks for sharing. Good pics too!
LikeLiked by 1 person