Sheboygan California Gull

Yesterday, I was joined by Ethan Gyllenhall for my July, Wisconsin lakefront run. We found 8 species in Sheboygan, with the highlight being a CALIFORNIA GULL.

3rd cycle type California Gull. Sheboygan County, Wisconsin. 14 July 2017.

Perhaps a 2nd summer record for the state(?).

We also found an all-time Lake Michigan high of 69 Lesser Black-backed Gulls. We opined there must be well over 70 birds but chose to follow a strict protocol with our count.

1st summer Lesser Black-backed Gull. Sheboygan County, Wisconsin. 14 July 2017.

As usual, the majority of Lessers here are 1st and 2nd summer individuals, but for the first time ever, I had more than a handful of 4th cycle types. This leads me to an obvious conclusion - birds that have summered here for the last 3-4 years are now returning and they're being joined by younger cohorts.

3rd summer (now in it's 4th plumage cycle) Lesser Black-backed Gull.

Sheboygan County, Wisconsin. 14 July 2017.

I asked Amy Kearns this morning, how long before a few decide to nest in a nearby Herring colony, and her response was an astute, "If they aren't already"! By the way, Amy (a Biologist living in Indiana) had 50+ Lessers here earlier in the week. She seems to be much more enthralled by this phenomenon than most other birders. To put this event in perspective, no other place on the Great Lakes has seen this many Lesser Black-backed Gulls at one site, at one time. Ever. In fact, no place away from the Atlantic coast has recorded such summer numbers for the entire continent!

Just as interesting is to have lingering Glaucous Gulls on Lake Michigan in July. These birds should be waaaaay north of here at this time of year. We had this beast and a paler 2nd summer type.

First summer Glaucous Gull. Sheboygan County, Wisconsin. 14 July 2017.

First summer Glaucous Gull. Sheboygan County, Wisconsin. 14 July 2017.

A final bird of note here is a 1st summer type Franklin's Gull (different than the bird seen here in May & early June). We missed Laughing (seen by Amy a few days ago) and had zero Little Gulls (despite 500+ Bonaparte's littered about the beaches).

The Post-Thayer's Era

And so Thayer's Gull has at long last been put to rest. The AOS (AOU) Committee on Classification and Nomenclature has voted unanimously on the proposal to lump thayeri with Iceland Gull (2017-C-7) .

The question was not so much whether there was an irrevocable need to retire the species altogether. Rather, the matter of contention was that there was never sufficient evidence to recognize the Iceland Gulls (nominate glaucoides, kumlieni and thayeri) as unique "biological" forms. I could not agree more. Whether we call all 3 taxa Iceland Gulls or any other suitable English name is inconsequential - so long as they're regarded as conspecifics in the present.

First cycle Thayer's [Iceland] Gull (L.g. thayeri). Waukegan, Illinois. December.

The overwhelming majority of birders alive today, including myself, have always known Thayer's Gull as a species. Witnessing a taxonomic lump of this magnitude is, without doubt, sobering.

Yet, how many of us were never aware that the decision to give Thayer's species status in 1973 was based largely on false pretenses? How many of us don't realize that thayeri has never been systematically described throughout its breeding range? How many birders still don't know of the multiple accounts that describe pale-winged and dark-winged birds purportedly interbreeding in several regions across arctic Canada? Add to this the fact that virtually zero amount of genetic work has been done in order to better understand these 3 similarly-behaving taxa, and it becomes clear that this lump was imminent!

An intermediate thayeri-kumlieni type that I prefer not to stubbornly label.

Michigan City, Indiana. January.

An intermediate adult thayeri-kumlieni type. Whiting, Indiana. February.

How is it, then, that anyone would be satisfied with checking off a "species" cloaked with so much ambiguity!? But I digress. This post isn't to argue the merits of lumping thayeri with the Iceland Gulls - that battle has already been fought and won (you can read my detailed opinion on this subject in a post I wrote earlier this year, Thayer's the Iceland Gull - One Species. Also, see my commentary on the recent proposal in Birding, June 2017. V49 N3).

First cycle Kumlien's [Iceland] Gull (L.g. kumlieni). Whiting, Indiana. December.

Adult Kumlien's [Iceland] Gull (L.g. kumlieni). Hammond, Indiana. February.

 

Moving Forward

I'd like to suggest that this classification will give fresh impetus to gull-watching and gull study in North America. Gone are the days where circular reasoning is permitted when discussing these forms. Intermediate and perplexing individuals will be called just that, with no impulse to pretend we understand their absolute pedigree. Rightfully, a hefty burden of proof is placed on any contemporary worker who attempts to untangle this complex.

Iceland Gull (L.g. glaucoides). First Cycle. Volusia County, Florida. January.

It's my hope that we'll build on the current identification papers at our disposal, and maybe, just maybe, a few brilliant students of ornithology will eventually get up to the breeding grounds and carefully study these high arctic denizens. At the very least, perhaps increased banding efforts, the use of GPS tracking and the collection of blood samples will be carried out throughout the wintering grounds, for starters.

All is not Lost

The omission of Thayer's Gull from our "checklists" doesn't any more or less change reality. Over the last couple of days, I've read remarks on social media such as, "Great, now I can stop looking for them", as if the task of finding a Thayer's Gull is similar to finding a mythical dragon. 'Tis not.

Adult-type Thayer's [Iceland] Gull. Lake County, Illinois. February.

There will still be a sizable population of dark-winged birds that we will systematically identify as Thayer's [Iceland] Gulls come this Fall/Winter. The only difference is, now, we can enjoy the inherent variation found in this complex without illogical consequences.  

Monthly Notables June 2017

• Thayer's Iceland Gull (1st cycle). Gambell, Alaska. 01 June 2017.
• Franklin's Gull (2nd cycle type). Barnstable County, Massachusetts. 02 June 2017.
• Western Gull (adult). Sitka, Alaska. 02 June 2017.
• First Summer Record.
• Franklin's Gull (adult). Sitka, Alaska. 02 June 2017.
• First Summer Record.
• Black-headed Gull (2nd cycle). Northumberland County, Ontario. 04 June 2017.
• Herring Gull (1st cycle). St. John's County, Newfoundland. 05 June 2017.
• Apparent European Herring Gull. All flight feathers intact.
• Common Gull (1st cycle). St. John's County, Newfoundland. 05 June 2017.
• Lesser Black-backed Gull (2nd cycle type). Clay County, Minnesota. 05 June 2017.
• First county record.
• Thayer's Iceland Gull (2nd cycle). Manitowoc County, Wisconsin. 05 June 2017.
• Ivory Gull (1st cycle). Nome County, Alaska. 07 June 2017.
• Ross's Gull (1st cycle). Nome County, Alaska. 07 June 2017.
• Black-headed Gull (1st cycle). Nome County, Alaska. 07 June 2017.
• Franklin's Gull (adult). Barnstable County, Massachusetts. 07 June 2017.
• A different individual than that seen on 02 June 2017.
• Glaucous Gull (3rd cycle type). Pinellas County, Florida. 09 June 2017.
• Black-tailed Gull (1st summer). Nome Census Area, Alaska. 13 June 2017.
• Laughing Gull (1st summer). Kearny County, Kansas. 16 June 2017.
• First County Record.
• Sabine's Gull (adult). Adams County, Washington. 16 June 2017.
• California Gull (adult). Churchill & Manitoba County, Manitoba. 16 June 2017.
• Little Gull (2nd cycle). St. Clair County, Michigan. 22 June 2017.

10 Species Day-list:

Manitowoc County, Wisconsin. 05 June 2017.

Nome County, Alaska. 07 June 2017.

Barnstable County, Massachusetts. 07 June 2017.

Churchill & Manitoba County, Manitoba. 16 June 2017.

Notes:

Most notable this month is Thayer's Gull losing species rank with the AOS (28 June 2017). This taxon is now one of 3 subspecies of the Iceland Gull, Larus glaucoides thayeri.

Two adult Bonaparte's Gulls were observed near a gull colony in Raudasandur, Iceland. The observers report aggressive displays and flights, and hinted that the species is most likely nesting at the site. As of this summary (01 July 2017) no nest has been reported.

It appears Heermann's Gull has suffered another poor breeding season on Isla Rasa, Baja California. Over 100 adults were observed as far north as Vancouver by mid-June. Thus far only 3 juveniles have been reported this season. Observers are encouraged to carefully report ages seen in the field. One question to ponder is whether the number of 2nd cycle type birds has decreased - this may be an indirect way to census the previous year's young.

A dozen or so Lesser Black-backed Gulls - primarily subadults - spent the month scattered about the interior of the continent. Although this steady increase of summering Lessers is somewhat expected, the distribution is random and fragmented from year to year (most likely associated with available food sources).

An apparent Chandeleur Gull (American Herring x Kelp) was photographed on the Mississippi Gulf Coast on 21 June 2017. Plumage characteristics suggest a 4th cycle type.

June 2017 Quiz

Age: The largely dark brown wing coverts and substantial tail-band suggest a 1st cycle gull.

Identification: This is a hooded species with obvious eye-crescents. The dark-gray mantle and scapular feathers eliminate paler species such as Bonaparte's, Little and Sabine's Gull. Although not discernable from this single photo, the bill and body size should aid in the elimination process when observed in the field. The only reasonable choices for this 1st cycle gull are Franklin's and Laughing.

This month's quiz bird is a rather typical 1st winter Laughing Gull, photographed in Volusia County, Florida. January.

For comparison, consider this 1st cycle Franklin's Gull. Illinois. September.

First cycle Franklin's show a silvery gray wash across the greater coverts - and perhaps diagnostic - white outer edges to the outermost rectrices. Overall, this species will show whiter underparts and hindeck earlier in the season than Laughing. Finally, Franklin's will often show a much more demarcated semi-hood and wider eye crescents than similar-age Laughing Gulls.

Bonaparte's Are Fast - Peregrine's Are Faster!

We often see Peregrine Falcons buzzing flocks of gulls and then half-heartedly aborting and changing their intent for reasons unknown to us. Yesterday while wedged between two large boulders on the Manitowoc lakefront, I patiently sat for almost 3 hours admiring a few Little Gulls in a sizable feeding flock of 500+ Bonaparte's Gulls. Suddenly, ALL of the birds took to the air and headed east over the lake in unison. The birds moved with such urgency that I knew the only predator that can elicit such fear is a Peregrine Falcon. Not wanting to be discovered, I remained still and didn't raise my gaze. A few seconds later the falcon zipped right past me, some 75 feet out, and snatched a 1st cycle bird in midair as it tried to gain altitude. I had a fleeting thought it might be a Little Gull, but that wasn't the case.

This one-year old Bonaparte's was a couple of seconds too slow.

Monthly Notables May 2017

• Black-tailed Gull (adult). Kitimat-Stikine County, British Columbia. 04 May 2017.
• Slaty-backed Gull (3rd cycle). Lambton County, Ontario. 06 May 2017.
• This individual, presumably seen on the Thunder Bay CBC in January 2017, then in Muskegon, Michigan in April 2017, was resighted just outside of Sarnia, Ontario near the St. Clair River.
• Black-headed Gul (1st cycle). Erie County, Ohio. 10 May 2017.
• Slaty-backed Gull (adult). Chippewa County, Michigan. 19 May 2017.
• Black-tailed Gull (2nd cycle type). San Francisco County, California. 23 May 2017.
• Ivory Gull (adult).  Bonavista/Trinity-Clarenville County, NF & Labrador. 23 May 2017.

May 2017 Quiz

Age: All 3 birds are in high molt, with a mixture of old and new upperparts. The visible primaries on the rightmost and leftmost birds appear to be 1st generation (note the primaries on the center bird aren't visible). Thus, it's safe to say these large white-headed gulls are roughly 1 year of age.

Identification: Both individuals with bi-colored bills look like typical 1st summer Herrings - size and structure rule out smaller species such as Ring-billed, and the thick bills and heavy chests seem to rule out California Gull. The left bird - with a mostly black bill and attenuated look to the rear - is different.

Here's a slightly underexposed image of this individual:

The upperparts are genuinely dark with dark centers. Note the bill is relatively long, but straight, ending with a slight droop. The striated neck markings, and dark stippled tips to the new wing coverts, recall Lesser Black-backed Gull, and that's what this month's gull was identified as.

This first summer Lesser was photographed in Sheboygan, Wisconsin. June.

First Basic Outer Tail Feathers on Bonaparte's Gulls

A quick note on 1st cycle Bonaparte's and their tail bands. Specifically, what is the pattern on the outer rectrix (R6)? Does the blackish band extend onto the outermost feathers? Seems like a simple question.

In their account on "juveniles", Olsen & Larsson describe T6 (=R6) as being white with white tips. But in the "first summer" account, they imply the outer tail feather does have black markings. This is somewhat confusing and should be clarified.

First cycle Bonaparte's Gull. R6 apparently white. The tail band on this individual doesn't extend onto the outermost tail feathers. Cleveland, Ohio. November.

Howell & Dunn, however, note that some pigment is found on the outer tail feathers, but limited to the inner webs.

As described in Gulls of the Americas, this individual shows some black on both outer tail feathers, but the pigment is limited to the inner web. Evanston, Illinois. April.

Looking through tens of 1st cycles in my photo collections, I mostly agree with Howell & Dunn, that on average, when there is black on the outer tail feathers (which is rather common), the black is generally limited to the inner web. But not always. Some individuals clearly show pigment beyond the feather shaft.

First cycle Bonaparte's Gull with pigment on R6. The pigment crosses over the feather shaft and onto the outer web on the left R6. New Buffalo, Michigan. September.

Interestingly, when viewing the ventral side of the tail on those individuals with pigment on R6, it usually appears there's more pigment from below than above. This, I suspect, is mainly because the inner webs of the outermost tail feathers are more visible when viewed from underneath. From above, the outer webs are more exposed.

Left R6 shows a substantial amount of pigment. Manitowoc, Wisconsin. May.

Although the pigment spills onto the outer web of R6, it doesn't reach the outermost edge of the feather. Chicago, Illinois. November.

As I've found with 1st basic Franklin's, Black-legged Kittiwakes, Little and Laughing Gull, the pigment on the outermost tail feather appears to be more variable than generally thought. I suspect the same might hold for other species such as Sabine's and Black-headed Gull.

Wisconsin May Run

Late spring through early summer often brings good gull diversity on the Wisconsin, Lake Michigan lakefront. Here, I can often find a few straggling northern species along with hooded migrants. Last Sunday was a great demonstration of this phenomenon with 10 species between Port Washington, Sheboygan and Manitowoc. Couple this with hundreds of sub-adult Herrings in high molt and the hours spent here are well worth any gull-watcher's time and effort.

The highlight for me was this hyper-melanistic 1st cycle Bonaparte's. I've seen 5 or 6 of these now, with this bird being the most cooperative. Although they're reported annually, these types are rare enough to make one do a double-take.

Possibly a 1st alternate Franklin's where all primaries are renewed

in the first plumage cycle (via PA1).

First cycle Lesser Black-backed (1st summer).

Second cycle Lesser Black-backed Gull (1st summer).

Inner-primary molt signals PB2 has commenced.

Second cycle Great Black-backed Gull (1st summer).

Putative 2nd cycle Glaucous x Herring (1st summer). Photo 1 of 2.

Putative Glaucous x Herring. Photo 2 of 2.

Second cycle Thayer's Iceland Gull (1st summer). Photo 1 of 2.

2nd cycle Thayer's Gull with what appears to be a similar-aged Herring Gull.

Of interest is what appear to be adult-like tips to the 2nd generation (?) primaries coming

in on the Herring. Whether or not the Herring is a 1st summer bird is uncertain. Nonetheless,

I do have suspicions that 2nd basic primaries on some of our Herrings can appear adult-like.

1st summer Kumlien's Iceland Gull. Primary molt has likely begun

but no open wing was observed.

This 1st summer Glaucous Gull tried to go unnoticed but it's difficult to that when you tower over

everything around you. First summer Lesser Black-backed in the background

Monthly Notables April 2017

• Ivory Gull (adult). Nome County, Alaska. 01 April 2017.
• Great Black-backed Gull (1st cycle). Larimer County, Colorado. 01 April 2017.
• Continued from March 2017.
• Black-headed Gull (1st cycle). Glynn County, Georgia. 04 April 2017.
• Laughing Gull (1st cycle). Monterey County, California. 05 April 2017.
• Sabine's Gull (adult type). Yolo County, California. 07 April 2017.
• Slaty-backed Gull (adult). Clatsop County, Oregon. 08 April 2017.
• Lesser Black-backed Gull (adult). Monterey County, California. 11 April 2017.
• 4th County record. 
• Laughing Gull (adult type). Lincoln County, Oregon. 11 April 2017.
• 4th State Record.
• Franklin's Gull (adult). Kings County, Nova Scotia. 14 April 2017.
• Slaty-backed Gull (3rd cycle type). Muskegon County, Michigan. 19 April 2017.
• Michigan's 3rd April record of Slaty-backed Gull. A photo from the Thunder Bay CBC in early January (2017) suggests this may be the same individual, found some 400 miles to the southeast.
• Lesser Black-backed Gull (adult type). Socorro County, New Mexico. 29 April 2017.

Notes

1. Worthy of mention is what appears to have been a "surge" in Lesser Black-backed Gull sightings on the Central California coast this past season. Interestingly, this was also the case for Oregon where there were 3 coastal sightings (previous to this the state only had one coastal record).