01 August 2015

July 2015 Quiz

Age: The wing coverts have a plain but marbled pattern, pointing away from a first cycle gull. The tertial tips also show relatively broad pale tips with a similar marbling effect - this all points away from a first cycle. The short primary extension suggests the outer primaries may still be growing, and when zooming in, one can make out rounded tips to these primaries. This looks like a typical 2nd cycle type large white-headed gull. 

The bill appears large and strong when compared to the adult California Gull in the background. In addition, the quiz-bird has thick legs and a noticeably larger and heavier body when compared to the Cali Gull. The eye placement is somewhat high and forward, and this gives a more beady feel to the eye, especially for such a large head. Looking closely at the newer scapulars, they appear dark gray and resemble Western and/or Yellow-footed Gull.

As always, it would help to know the date and location when assessing any photograph: mid-September, San Mateo County, California. A 2nd summer Yellow-footed Gull would typically have much more advanced, adult-like gray upperparts at this point, and would be rare anywhere in the United States away from the Salton Sea. This month's gull is a fairly straight-forward 2nd summer Western Gull completing its wing molt via a 2nd prebasic molt.

Monthly Notables July 2015

July 2015 Notables

  • Mew Gull (apparent 3rd cycle type). San Francisco County, CA. 01 July 2015. Continuing from late May.
  • Little Gull (1st summer). Dane County, WI. 01 July 2015. Continuing.
  • Little Gull (1st summer). King County, CA. 01 July 2015. Continuing.
  • Glaucous Gull (2nd summer). Manitowoc County, WI. 06 July 2015. Continuing. 
  • Chandeleur Gulls (Kelp x Herring hybrids, 20+). St. Bernard County, LA. 08 July 2015.
    • By far the most exciting news in the ABA area this month. A small team of surveyors from LSU found multiple adult and sub-adult putative hybrids on Chandeleur Island on 08 July, and then again on 10 July 2015. Per Dan O'Malley, 3 nests were found (one empty, one with two eggs, and one with one chick being protected by adult-type hybrids). Hybrids from this island have not been reported post-Hurricane Katrina. More on the history of this hybridization event can be found here. Access to the island is restricted.
  • Lesser Black-backed Gull (2nd summer). Sedgwick County, CO. 12 July 2015.
  • Glaucous Gull (1st summer). Ottawa County, MI. 15 July 2015.
  • Black-legged Kittiwakes (24 - 1st summer). Barnstable County, MA. 18 July 2015.
    • Unprecedented summering numbers in and around Provincetown.
  • Iceland Gull (1st summer). Barnstable County, MA. 19 July 2015. 
  • Lesser Black-backed Gull (apparent adult). Keith County, NE. 19 July 2015.
  • Great Black-backed Gull (1st summer). Mobile County, AL. 21 July 2015. Continuing.
  • Laughing Gull (Fresh Juvenile). Manitowoc County, WI. 23 July 2015.
    • Intriguing. Found exactly where two adult Laughing Gulls were previously sited earlier in the season. The adults appeared to be paired up, exhibiting courtship displays and calling together in late May and early June. They then disappeared together and were not sited thereafter.
  • Laughing Gull (adult type). Douglas County, KS. 25 July 20015.
  • Black-headed Gull (adult). Barnstable County, MA. 27 July 2015.
  • Sabine's Gulls (High Count - 1,870). Monterey County, CA. 28 July 2015.
    • Extraordinary. Mostly alternate adults observed from land at Pt. Pinos Seawatch.

28 July 2015

July Lesser Black-backeds on the Cape Cod Peninsula

The frequency at which Lesser Black-backed Gulls are being seen along the Atlantic coast in the summer months continues to steadily increase. There are some sites where the species is locally abundant and is found in the hundreds (such as Chincoteague NWR in Maryland and Virginia). But at other sites, Lessers tend to be unpredictable, seen by the tens and even hundreds one week, and then all but non-existent the next week. Some of this may be due to observer-bias, but also likely is a rapid turnover rate as the species moves out at sea or up and down the coast in search of a food source.

A not so uncommon summer sighting on the mid-north Atlantic coast, a Herring, Lesser Black-backed and Great Black-backed, all seen together. Provincetown, MA. 18 July 2015. 
Similar to when I wrote about the status of LBBG in Birding magazine a few years ago, the age distributions are still consistently in favor of young birds - mostly 1-2 year-olds in the midst of complete molts. Rarely do I find evidence of definitive adults being recorded in the breeding season.

It seems to me, however, that a percentage of younger birds may be going unnoticed in Herring and Great Black-backed flocks, especially as one moves north into New England where the latter two species are found in greater numbers.

A mixed flock of Herrings, Great Black-backeds and Lesser Black-backeds. How many LBBGs do you see in this photo?
Certainly a percentage of any species will go "unnoticed" without comprehensive counting efforts, but I feel it's especially true with immature Lesser Black-backeds in the summer months (see for example what I discovered on the Wisconsin lakefront a couple of summers ago).

Earlier this month I spent a total of 3 days surveying gulls at two sites along the northernmost point of the Cape Cod peninsula: Herring Cove & Race Point Beach in Barnstable County, Massachusetts. These two locations hold an impressive diversity of summer gulls, and one need not look any further than recent eBird reports to verify this. Surprisingly though, high counts of Lesser Black-backed Gulls reported at these sites in early July 2015, by reliable observers who regularly count birds at these locations, were 5 and 8, respectively. Below are my high counts.

High Counts:
Herring Cove. 18 July 2015. 27 Lesser Black-backed Gulls
(22 1st summer, 4 2nd summer, 1 3rd summer).

Race Point Beach. 19 July 2015. 39 Lesser Black-backed Gulls
(21 1st summer, 13 2nd summer, 3 3rd summer, 2 4th summer types).

I don't mean to be critical of the experienced birders that frequent these sites as I'm sure they're perfectly capable of identifying sub-adult Lesser Black-backeds. But as one birder put it to me, the attitude in the summer months is much like this: "I'll just add any gulls I didn't feel like looking at to the HERG count".

GBBG, HERG, GBBG, LBBG. Barnstable County, MA. 19 July 2015.
So in effect what may be happening with many birders is that they find a few LBBGs, check the species off for the day, and then proceed to not pick through larger gull flocks. In other words, they're not actively looking for Lessers but will count any obvious birds that are caught in their peripheral (I suspect this happens with other species from various families as well). In addition, certain sites are birded while stationary, and would there have been more miles put in surely more LBBGs would turn up in these day-list totals.

Advanced 2nd summer type LBBG, 4th summer type GBBG and 1st summer LBBG. 
4th summer GBBG (Appledore Island Black 9M0, born in 2012) and 1st summer LBBG.
1st summer LBBG and 1st summer GBBG.
First summer LBBG and GBBG
Two 3rd summer type LBBGs, one 1st summer type and an adult type HERG. The second bird from the left is big-billed, big-bodied and has noticeably pale upperparts. I do suspect it may be a LBBG x HERG hybrid (so called Appledore Gull).
Very similar in plumage aspects, these 1st summer cousins are readily told apart by size and structure.
Both this bird and the individual below appear to be 4th summer types, and not yet definitive adults.
Perhaps the maturest LBBG I've seen in July on the Atlantic coast. Barnstable County, MA. 19 July 2015.
Flight shot of the same individual pictured above. Secondary feather replacement nearly complete but it appears to be a "stepwise" molt.
I've received several requests in the last few weeks about identifying first summer Lesser Black-backeds. Stay tuned for an upcoming post where I'll describe identifying this age group in its first plumage cycle.

And now the answer to the "number of LBBGs" from the photo in the beginning of this post:

A total of 8 LBBGs in this frame. Barnstable County, MA. 19 July 2015.

23 July 2015

Summering Black-legged Kittiwakes in Provincetown

Unprecedented numbers of Black-legged Kittiwakes - all first summer individuals - have been summering on the northern-most point of the Cape Cod peninsula. I had the opportunity to spend some "quality" time with a group of no less than 24 birds at Race Point Beach last weekend in Barnstable County, Massachusetts. All photographs taken here were on 18-19 July 2015.

Most upperwing coverts molted, bills have turned mostly yellow and the hind-neck collar is all but non-existent.

Left bird showing some brown spotting on the lesser upperwing coverts and more black to the bill tip.

Two right outer tail feathers and p9-p10 retained. Note the darker upperparts when compared to the 2nd generation primaries.

Outermost tail feather retained on both sides. Only p10 retained. S1-S4 renewed.

The individual standing front-left has a very white head and neck, almost 2nd summer like, but it is indeed still holding on to first basic outermost primaries. This is simply an advanced first summer bird with no earmuffs or gray neck. See the next 2 photos.

The brown, juevenile, wing coverts are exposed here but notice how much of this is covered at rest.
Two individuals with a single first summer Bonaparte's and Laughing g

This last bird was my favorite of all, standing with a firm and typical kittiwake posture. But what good is a Black-legged Kittiwake photo without the legs showing?!

22 July 2015

Off-island Resights of Herring & Great Black-backed Gulls: Mid-July

While working my way up and down the Massachusetts and New Hampshire coast last week, I found several off-island Appledore gulls.

Herring Green 42A. Banded as a chick on 18 July 2014. Seen here on 16 July 2015. Rockingham Co. New Hampshire.

Herring Green U03 was banded  as an adult on 29 May 2014. Seen here on 16 July 2015. Rockingham Co. New Hampshire.
Great Black-backed BLACK 9M0. Banded on 16 July 2012. Seen here on 19 July 2015. Barnstable Co. Massachusetts. 
Seen here with its younger cousin, a first summer Lesser Black-backed.

Above, BLACK 9M0 is undergoing 4th prebasic molt. By the end of the fall, we'll call this individual a 4th cycle - essentially an adult, or adult-type if sub-adult plumage features are present. All secondaries (?) and tail feathers retained 3rd basic. The 4 inner primaries, p1-p4 are 4th generation (4th basic) while the older, mostly black, outer primaries are 3rd generation (3rd basic). Note how big the p10 mirror can be on a 3rd cycle Great Black-backed Gull.

The p10 mirror is not so apparent at this angle.
Herring GREEN X82. Banded as a chick on 12 July 2013. Seen here on 19 July 2015. Barnstable Co. Massachusetts. 
Just as expected for a Herring born in the summer of 2013, this bird is undergoing its 3rd prebasic molt with 3rd generation inner primaries growing in. Note the 2nd basic tail, secondaries and outer primaries.

Thanks to Bill Clark for providing these life histories!

Great Black-backed with Pseudo-Mirror on P8

Not too many large white-headed gulls develop a 3rd mirror on the 8th primary. Common Gulls regularly do, but Great Black-backeds??

Olsen and Larsson note that about 10% of males and less than 1% of female GBBGs develop a small mirror on P8 (~35mm in males and ~10mm in females). Simply put, it's not commonly seen by most field observers. So I was super excited when I found this bird circling "The Devil's Dance Floor" on Appledore Island recently:

Adult GBBG with triangular-shaped mirror on p8 and two white tips to p10 and p9. Notice the relatively thin white tips to the inner primaries when compared to the mid-secondaries. This is quite different than Western, Slaty-backed and Kelp Gulls.
I'd give up chocolate for the rest of my life to know how old this individual is and how this primary pattern progressed as it aged.

Deviate Leg Color in Adult-type American Herring Gulls

It seems too often birders are confused by adult type Herring Gulls with unfaithful leg color. It's known that Herring is a pink-legged species, but the Spring and Summer season often produce some interesting leg patterns.

Adult-type Herring Gull with typical pink-colored legs. Daytona Beach Shores, FL. January 2015.
A not too uncommon leg color one may find is a pale straw-yellow:
Adult-type Herring with an obvious yellow tinge to its legs. Portsmouth, NH. 16 July 2015.
The other deviate leg color is a cold bluish-gray, like this:
Adult-type Herring with bluish-gray legs. Portsmouth, NH. 16 July 2015.
Variation in large white-headed gulls is wide, and it's unfortunate that some would rather invoke the "hybrid" or "rarity" label when encountering birds like this. Why these birds develop such leg colors is not fully understood but I have a few theories.

The former bird with yellow legs is a color one will most likely see in early Spring. The latter, with bluish-gray legs, is a color that is noted frequently with Herrings along the Atlantic coast. This might suggest that those with yellow-colored legs develop via hormones, whereas the bluish legs may be related to a food source on the Eastern seaboard.

21 July 2015

Gull Banding on Appledore Island

I had the honor of visiting Appledore Island off the coast of Maine/New Hampshire last week. The 95 acre island is the largest of a cluster of islands in the Gulf of Maine, referred to as The Isle of Shoals.

Appledore Island - Copyright Shoaler

Trolling into the dock on a zodiac. Photo by Bill Clark. 
Admittedly, this trip was long overdue. The lure for me is an extensive banding program that uses large, colored, field-readable bands on Herring and Great Black-backed Gulls - a rather unique project that's unmatched in the United States when it comes to gull banding. Dr. Julie Ellis of Tufts University began banding gulls here in 2004 and she's spearheaded the program since. The program is contributing much information on the migratory patterns, survival rates and behaviors of these birds.

The island is home to nearly 850 pairs of HERGs and about 500 pairs of GBBGs. Here's a neat video produced by the Cornell Lab of Ornithology showing how these birds carve out and maintain territories on this relatively small spit of land.

Adult Lesser Black-backed - Green F05, also known as Pierre.
Daytona Beach Shores, FL. January 2015.
You'll recall this is the same site where Dr. Ellis and her colleagues found the now infamous male Lesser Black-backed Gull (Green F05) nesting with an adult Herring in 2007 (and then subsequently in 2008 and 2009). Thereafter, I began referring to the putative hybrids of these two species as "Appledore Gulls". Much remains to be learned about identifying this presumably increasing hybrid in North America. The hybrid chicks - some banded - have been documented with photographs along the Atlantic seaboard, all the way down to Florida and Alabama.

As I arrived on the island I was met by gull connoisseur, Bill Clark. Bill has devoted much time and energy with these birds, and he's been instrumental with the program's on-going success. As we began walking away from the dock, I immediately sensed just how comfortable the gulls are here - some apparently having nested and now caring for their young right along the walking paths leading to the lab. 

Multiple pairs of HERGs & GBBGs sat near the entrance to our dorms.
An adult GBBG with its chick allowing us to pass.
David Botner and the summer interns.

After a short tour and a generous lunch, I was cautioned about the notorious Appledore Clover (poison ivy) and our chick-banding commenced. I was drawn by how fast this team of young students, led by Cornell's Dr. David Bonter, worked. They had already banded some 40+ chicks that morning and were now going for round 2, which resulted in another 32 chicks being banded.

Shailee and Dallas double-checking a weight.

Much care is taken to ensure the chicks are released back onto their parent's territory. Not doing so can easily result in the chick's demise as other territorial adults quickly move in for the attack. That's simply the nature of these colonial nesters.

Yours truly ready to release a GBBG chick. Helmets are
always in order when entering the colony. I learned this
the hard way in a Ring-billed/Herring Gull colony in East Chicago once.
The chicks - almost all still flightless - were captured by hand after usually putting on a short chase through the rocky terrain. Brought back to an informal banding station in a cloth bag, they were fitted with a federal band and a field-readable band on separate legs. Next, a blood sample is taken from the underwing, a preen-gland feather sample is cut, and a wing measurement is noted. Finally, the chick's weight was recorded along with any pertinent notes such as "Chick A, B or C", with any sibling relations noted.

GBBG chicks with federal and field-readable bands. Copyright UNH.
The parents, although mildly stressed and agitated, seem to anticipate the return of their young. This pair flew in and sat just a few feet beside us, watching as we banded their chicks.

Adult GBBGs (presumably the male in front and female behind).
Federal bands are coupled with a field-readable band.
Herrings guarding their chicks.
Boundaries being maintained via long calls.
The rocky niche where Green F05 was first discovered nesting.
The gulls frequently follow the local fishing boats off the island.
Nature governs as it will.

A physical altercation that ended with the Herring on the left having the upperhand.
Adult GBBG (Black 9Z6) with chick standing in the day's last hour of sunlight.
As day 1 came to its end, we gathered outside on the front steps and took in a mesmerizing sunset over the mainland. Some respite time was much deserved as we'd awake the next morning at sunrise and repeat the banding circus all over again - I was stoked!

You might remember that last spring I found one of Appledore's young Great Black-backeds some 1,000 miles away in Whiting, Indiana on southern Lake Michigan. Earlier this year, I resighted Green F05 (Pierre) in Daytona Beach Shores, Florida. Exciting stuff! You too can help track these gulls by taking a little time to sort through your local gull flocks!

The large field-readable bands have made it easy for anyone to contribute to this project, and it's this message that I hope my reader takes from this post. Color bands are gaining much popularity as more gull banders in North America begin to utilize them. You can read more about the Gulls of Appledore Island and the ongoing research, here. You'll find information on where to report a banded gull should you encounter one. Every resight helps strengthen the vast database of information that's being accumulated. There's much more to be learned about this avian family that's so commonplace on our continent.

Thanks to Julie Ellis for extending the invitation and Bill Clark for entertaining all of my questions and hosting me. I'd also like to thank David Bonter for his patience and cordiality, and allowing me to tag along and help band some of this season's chicks.