This week I was able to get out to one of my favourite gulling locations out Sooke way. It was an atrociously dark morning due to a weather system along Vancouver Island's outer coastline, so photos were far from good that day, but it was still very nice to re-familarize myself with the classical winter forms. First cycles and adults were on the menu, although a few 2nd-cycles did catch my attention.
Early morning glow.
The weather the morning of.
Oct. 9, 2023.
Otter point visible in the distance, rain close behind.
Many of the gulls were spread thin and only really visible by scope a lot of the time.
Oct. 9, 2023.
I estimated approx. 2,500 gulls present, spread from where I was standing all the way out to Otter Point. It was clear that many of the expected species were back in full force. Close to 200 Thayer's and a dozen or so Cook Inlet Gulls mixed in with hundreds of California and Olympic Gulls. Plenty of Short-billed Gulls as well. Didn't see any Bonaparte's yet, but I'm sure the big wave of them has soon to follow. All the birds seemed focused on either effortlessly plucking or skimming up small schools of bait fish shimmering on the surface of the water. Throughout the morning congregations shifted tirelessly from east to west across the Strait. Below are a collection of gulls I encountered that morning . Most of which are of birds that came zipping past the point (bit of a blind corner at this spot).
1st-cycle Western-ish Gull.
Difficult know know what such birds will look like as adults and if they are hybrids. Overall this bird shows features many pro-Western: blackish primaries, tertials, and secondaries, nicely tipped greater coverts, median and lesser coverts without a checkered pattern (often shown by GWGUxWEGU), and oblong-shaped scapular feathers with pale edging confined to the edges (no pale indentations).
Sooke, Oct. 9, 2023.
Adult Thayer's Gull actively replacing primaries.
P10 retained (old), P9 completely missing, P8 emerging near the primary coverts (new), P7 growing in (new), P6-P1 complete (new). There's an odd greyish cast to the inner web of P10 which stands out to me as being atypical. Perhaps this shadowy effect is due to wear, as this feather is older?
Sooke, Oct. 9, 2023.
Adult Thayer's Gull.
Well marked bird with lots of black in the wingtips. It might not look like it, but this bird is also in the midst of replacing primaries -- P9 is missing, but P10 is covering this up because it's overlayed awkwardly across. White headed.
Sooke, Oct. 9, 2023.
1st-cycle Thayer's Gull. Lookin' fresh!
A lightly marked and softly plumed compared to other Thayer's at this age. Well marked median/lesser covs, neatly tipped greater covs, perfect venetian blind effect to the primaries, and a wide window puts this bird in the Thayer's camp. A closer inspection of the scapular pattern only helps to bolsters the former ID. This pattern is classic for juvenile scapulars in Thayer's (thick pale perimeter, plain coffee-brown centres). I've sometimes heard this referred to as "alluvial fans" and they are very distinctive if present (not all 1st-cycle Thayer's will have this pattern). The dark mask, light collar, and "MacGillivary's Warbler" facial expression created by the pale lower eye arch again help support the ID of Thayer's.
Looks like it probably had a very strong tail band too (rare in Herring and Cook Inlet).
Sooke, Oct. 9, 2023.
Adult Thayer's Gull.
P10 & P9 missing, P8 emerging, P7-P1 complete. You can also see a chunk of secondaries have been dropped. Few head streaks beginning to show up.
Sooke, Oct. 9, 2023.
1st-cycle California Gull left, adult Thayer's Gull right.
Sooke, Oct. 9, 2023.
1st-cycle California Gull.
Very snazzy and eye catching. Blackish gull with a strongly bicoloured bill, the dark inner primaries (lack of a window) help to set this bird apart from other first cycles like Herring. 1st-cycle Black tailed Gulls can look very similar at first glance, however BTGUs show clean, all white rumps.
Sooke, Oct. 9, 2023.
Adult Heermann's Gull.
The snazziest and most eye catching gull in the PNW. This one is well a head of schedule with its molt -- practically in full basic plumage already, and flight feathers almost completely finished molting in.
Sooke, Oct. 9, 2023.
Sub-adult California Gull. Presumed 4th winter.
Very adult-like appearance, yet a closer examination of the forewing around the alula + primary covs is enough to see this bird is not fully mature. The small black markings on these feather groups is a sign this bird is not yet fully mature (≥5th year).
Sooke, Oct. 9, 2023.
Adult Thayer's Gull.
P10 is retained (old), P9 missing, P8 emerging (new), P7 & P6 almost done growing in (new). Head streaking starting to take hold.
Sooke, Oct. 9, 2023.
Adult Thayer's Gull still with a very white head.
Sooke, Oct. 9, 2023.
Easy to contrast this adult Thayer's Gull with the one above.
Pretty rare to see a Thayer's with this much head streaking in early October! It's more expected to see birds like this starting in November.
Sooke, Oct. 9, 2023.
Adult Thayer's Gull with a decent amount of head streaking.
Sooke, Oct. 9, 2023.
2nd-cycle Glaucous-winged Gull.
Sooke, Oct. 9, 2023.
Pretty sure this isn't a hybrid Glaucous-winged x Herring (aka. Cook Inlet).
The bill is on the larger end of Thayer's but not out of range. Orbital eye ring is deep purple which is also good for Thayer's. The mostly white P10 tip coupled with the P9 pattern would be rare to see on a Cook Inlet Gull.
Molt: retained P10-P8 (old), P7 missing, P6 growing in (new).
All greater coverts missing from this bird's wing.
Sooke, Oct. 9, 2023.
Adult Thayer's Gull with a slightly pale eye.
Sooke, Oct. 9, 2023.
2nd-cycle Western-ish Gull.
Even though the mantle feathers appear to be rather silvery, I don't think that should dissuade augments about this bird as Western Gull. At this age I believe the colour of those mantle features does not necessarily reflect the final adult mantle colour. They rest of the bird is spot of for Western Gull IMO.
Sooke, Oct. 9, 2023.
1st-cycle Short-billed Gull.
Precious.
Sooke, Oct. 9, 2023.
1st-cycle Glaucous-winged Gull-type.
Fairly uniform patterning and colour throughout this birds upperparts with soft markings to lesser + median + greater coverts and scapular feathers. Difficult, if not impossible, to know the hatch locality and ancestry of such individuals. My impression and gut feeling is this immature did not originate from VI. The tail band and sparely marked uppertail covs are interesting to me -- don't see that too often in Glaucous-winged Gulls.
Sooke, Oct. 9, 2023.
1st-cycle presumed Olympic Gull.
Similar in many ways to the above bird, however the wing coverts show rows of bold patterning (dark centres), and the scapulars are classic for Olympic Gull. There is some contrast between the light inner primaries and darker secondaries. This 'secondary bar' is absent in pure Glaucous-winged Gulls.
Sooke, Oct. 9, 2023.
Adult Thayer's Gull.
Retained P10, missing P9, P7-P6 emerging, P6-P1 complete, large section of secondaries missing.
Sooke, Oct. 9, 2023.
Sub-adult Thayer's Gull. Presumed 4th-cycle.
Like the adults, this bird is also in the midst of molting primaries as we can see P10 falls short and is growing in. Bill colour and black mark to the very outer primary covert are signs of immaturity.
Sooke, Oct. 9, 2023.
2nd-cycle California Gull.
Rather dark and BTGU-like!
Sooke, Oct. 9, 2023.
A more standard example of a 2nd-cycle California Gull.
Sooke, Oct. 9, 2023.
Features consistant with 1st-cycle California Gull: bicoloured bill, dark inner primaries with little contrast to adjacent primaries & secondaries (lacking true window), crisp 'needle' pattern on median + greater covs, and spotted uppertail coverts. The majority of 1st-cycle California Gulls have replaced their juvenile scapulars by this date, and we can see that has happened with the above bird.
Sooke, Oct. 9, 2023.
Unlike this California Gull above, this 1st-cycle American Herring Gull has a darkish bill, pale inner primaries (window), and checkered median + greater covs. The overall forewing is also much less blackish compared to California. Note the facial expression differences. The scapulars are fully juvenile and have a 'holy-leaf' pattern. This is a classic signature of Herring and so strong in this bird you could make a wreath!
Sooke, Oct. 9, 2023.
1st-cycle Herring / Cook Inlet Gull.
Looks very similar to the Herring Gull above, however the facial expression and dingy-brown plumage recall that of hybrid GWGUxHERG. In 5 years will this bird show hybrid characteristics? Will it have a pink orbital eye ring? Will it have truly jet-black Primaries or will they be greyish? Note: some of the juvenile scapulars have been replaced.
Sooke, Oct. 9, 2023.
Here are four images of this 1st-cycle gull.
I am really not sure what it is, but it could either be one of three things:
a) Thayer's
b) Herring
c) Cook Inlet
To me it doesn't fit nicely into any of the categories. Something about a round hole and a square peg?
I will leave this bird as Larus sp. and that is is PERFECT OKAY. Without concrete information about ancestry or hatch location we just will never know with interemediate birds like this one. We will never be able to diagnosis every individual. Sure we will have our hunches, but at the end of the day gulls are difficult. That makes them so fun.
Sooke, Oct. 9, 2023.
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| Typical October group. Sooke, Oct. 9, 2023. |
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