January 2015 Quiz

Most gull identifications are tied to age, so let's begin by establishing that. The all-brown scapulars, dark-solid tertials, and relatively neat upperwing coverts all belong to a juvenile bird. The pointed primary tips and mostly black bill also aid in ageing this individual.

We don't have any reliable references for size comparisons in the photo, but this appears to be a medium sized gull (smaller than a Herring Gull). The attenuated look to the wings helps narrow it down to a few species, but much more telling is the strong "cinnamon" color throughout which is only shown by two North American gull species: juvenile Ring-billed and juvenile California Gull (much more common on the latter). The bleached appearance to the chest, neck and forehead, as well as the straight tubular bill and decurved gape expression make this a pretty solid California Gull.

This plumage aspect is not uncommon among juvenile California Gulls - loosely named "Cinnamon Types". Photographed in mid-September in San Mateo County, California.  

A Thayer's-Kumlien's Gull: Whiting, Indiana

I got out to the Indiana lakefront today. It didn't take long for me to be reminded of what great gull-watching we have here on Lake Michigan in the winter season. It's not so much the number of gulls, but rather the variety that impresses me. In less than an hour I had Thayer's (4), Kumlien's (1), Glaucous (4), GBBG (32) and LBBG (2) checked off for the day. There was also a Thiceland Gull. Yes, a Thiceland...

An intermediate bird showing both Thayer's and Kumlien's features on the wingtip. Whiting, Indiana. 31 January 2015.

Looks mostly like a Thayer's Gull, but the two outer primaries are suspiciously pale. The mirror on p9 also extends across both vanes from edge to edge. All of this would've been fine until I saw it side-by-side with Herrings and Ring-billeds.

That wingtip is too pale for my taste and I don't feel compelled to call such birds Thayer's Gulls. So why not a Kumlien's? Mostly because of the full band on p5. Of 345 sampled Kumlien's, Howell & Mactavish noted only 17 with subterminal markings on p5, "but never a complete subterminal band". They go on to say that altough none of their sample showed a complete band, it does occur, "albeit rarely". My bird also shows black bleeding onto the inner web of p9, and the "fullness" of the subterminal bands from p8 down to p6 make me even less willing to call it a Kumlien's. So by Lake Michigan standards, we'll keep this bird in the "intermediate" file.

I also had a neat 3rd cycle Thayer's with pale eyes - my 24th third cycle type Thayer's in the Lake Michigan region this season.

Thayer's Gull (3rd cycle type). Whiting, IN. 31 Jan 2015. Photo 1 of 3.

Photo 2 of 3.

Photo 3 of 3.

I have big hopes for February...big hopes. The Black-tailed Gull population is approximately 750,000 individuals. There has to be one out there with my name on it. Bring it!

Primary Molt in Wintering Lesser Black-backeds: Florida

A significant percentage of adult/near-adult Lesser Black-backeds from east-central Florida (roughly 28.5"N, 81"W) showed variable p10 lengths in late January, 2015. Seventeen out of twenty-six also showed p9 feathers that were not fully grown.

A. Short-wing appearance. 

B. P10 mirror on underside of far wing still emerging. 

C. Pale-end bird.

D1. Green F05 with almost fully grown p10.

D2. P10 on left wing appears longer than right wing.

E1

E2. Note how p10 appears shorter than the previous photo when the
primaries are folded closer together.

E3

F1. Only about 30% showed mirrors on p9.

F2. Mirror on left p9 now unobstructed (see previous photo).

F3

G1. Very similar to bird F (more black on bill).

H1

H2. Asymmetric p10 growth on left and right wings.

H3. Very short left p10 (tip protruding under the greater primary coverts).

J1

J2

K1. Just about fully grown length on p10.

L1.

Adult with salmon-colored legs. P8 longest primary.

What this all means when trying to narrow down migration distances (or subspecies) is yet to be learned. But there is an ID implication that should be kept in mind: adults with primaries not fully grown appear shorter-winged. The overall impression of wing structure on standing birds is similar to American Herring (at least this would be so earlier in the season. Hence, there's potential for confusion where points may be given to a "hybrid" over pale-end graellsii. To make matters more interesting, some of these adult types may show leg color with pinkish tones. 

American Herrings: Florida

I never pass up the chance to watch Herrings, especially when I find myself away from Lake Michigan. While in east-central Florida last week, I photographed a mixed array of wingtip patterns on adults - some that resemble what I think of as "Great Lakes Herrings" and others with less pigmentation to the wingtips (larger birds that I associate with having a Northern or Northeastern place of origin).

The first two individuals seen below were the most extreme in terms of limited pigmentation in the wingtips, and look very much like so-called Newfoundland Herrings. 

Notice on this bird the large apicals on the outer primaries and the large amount of white on p6 and p9.

Brevard County, FL. 24 Jan 2015. PHOTO 1 of 2.

I knew I'd be impressed when this bird opened its wings: complete white tip to p10 and no subterminal band or marks of any sort on p5. Apparently, the lack of any markings on p5 is not too uncommon in St. John's (Mactavish, pers. comm.). Mactavish & Jonsson include a similar bird in Photo 5 in their article on Niagara Falls versus Newfoundland Herrings (Birders Journal, V10 N2).

Same individual above. PHOTO 2 of 2.

This one shows less black on the bill, but similar-sized apicals:

Brevard County, FL. 24 Jan 2015. PHOTO 1 of 2.

 P10 shows light black to the edges of both webs and p5 a very faint bar:

Brevard County, FL. 24 Jan 2015. PHOTO 2 of 2.

Now for beach birds - all photographed at Daytona Beach Shores in Volusia County.

Amber-colored iris on a seemingly perfect adult. Photo 1 of 2.

Small spot on outer edge of p4. Photo 2 of 2.

Photo 1 of 2.

Small streaks on greater primary coverts, small spots on p4s and single mirror. Black on outer web of p8 somewhat extensive. Photo 2 of 2.

Big bull head and strong bill with moderate head streaking. Photo 1 of 2. 

A single large mirror on p10 showing a bit more black on the outer primaries. Photo 2 of 2.

A smaller bird that gave a Thayer's imperssion from a distance. Photo 1 of 2.

Medim sized mirror on p10. Extensive black on entire p9 and much on outer web of p8. Broken band on p5. Photo 2 of 2.

Extensive head streaking and black subterminal ring on bill. Very small apicals and pinkish bill suggest sub-adult (see next photo). Photo 1 of 2.

This was predicted to be a sub-adult in the field before the open wing was seen. Black markings on tail and primary coverts/alula. Black on outer webs of p4. Photo 2 of 2.

A beautiful, medium-sized, adult with much white on the underside of the far wing. 

Thayeri pattern to p9, no subterminal marks on p5. Note p4 and p2 broken. Photo 2 of 2.

Another adult but showing pink tones on most of the bill. Photo 1 of 2. 

Thin broken subterminal band on p10, assymteric mirror size on p9s and broken subterminal bands on p5. Photo 2 of 2. 

Obvious sub-adult per the large tertial spot. But not the strong, bright yellow bill. Photo 1 of 2. 

Tertial spot covered by scapulars in flight. Relatively extensive black on wingtip can be age-related. Interestingly, the black band on p5 is a faint color and not as black as p9-p10. Photo 2 of 2. 

Another large bird with relatively large white apicals. Photo 1 of 2.

Mirror only on p10. Black on p8 reaches close to primary coverts. Photo 2 of 2.

Artsy Photo of Pierre

It seems Green F05, or Pierre, couldn't stay away from me. I've found him at Daytona Beach Shores on four consecutive days in the last week. I had no choice but to get a little artsy with this photo opportunity I had last Sunday.

Lesser Black-backed Gull (adult). Volusia County, Florida. 25 January 2015.

You can read more about Pierre's legacy, here.

Anomolous and Aberrant Laughing Gulls

With literally over 50,000 Laughing Gulls to pick through in Brevard and Volusia Counties last week, I was able to find a couple of birds that stood out in the ranks. I give you an "anomaly" and an "aberrant".

This first bird shows aberrant bare-part coloration. This orange-red color problem has been documented in the literature and doesn't appear to be too uncommon with Laughing Gulls. For whatever reason it tends to be found more in this species than other dark-legged hooded gulls.

Adult Laughing Gull. Daytona Beach Shores, FL. 24 Jan 2015.

This next individual has molted into a complete hood in the middle of winter - a real anomaly:

Adult Laughing Gull. Daytona Beach Shores, FL. 25 Jan 2015.

I've seen Bonaparte's with full hoods in late Fall and have seen photos of Franklin's with complete alternate hoods in winter (birds that perhaps had breeding hormones triggered a bit prematurely), but this was my first LAGU with a black head in winter. Stunning to say the least!