Jeannette and I just returned from three days of visiting friends, family, and rare gulls in Gloucester, Mass. My friends from New Jersey Audubon were leading their annual trip to Eastern Mass this weekend, Jeannette’s Aunt from Norway was visiting, and there were a ridiculous number and variety of gulls – both regular and rare – this winter in and around Gloucester. As if we really needed an excuse to visit Cape Ann in winter, now we had three excuses, so off we went!

The gull-watching has been a larophile’s dream this winter, with unprecedented numbers of Iceland and Glaucous Gulls, huge numbers of the usual abundant species (Herring and Great Black-backed, plus smaller numbers of Ring-billed), and a few “Megas.” Three or more Thayer’s Gulls have been seen on occasion, but the real headliner has been a Slaty-backed Gull, a very rare visitor from Siberia, (or two, as there had been two earlier in the winter) that has been frequenting the various Gloucester gull hot-spots, including Niles Pond and Eastern Point Light, both of which are in my in-law’s neighborhood. While I have seen a number of Slaty-backs during my stints on St. Paul Island in Alaska, Jeannette has not seen one, so this was a primary target.

My hypothesis as to why this amazing aggregation of birds is occurring here this year is related to the fishing industry. Groundfishing boats from Maine are fishing in the Gulf of Maine, but bring their landings to Massachusetts, especially Gloucester, because they are allowed to land by-catch lobsters in the state – and that is strictly prohibited in Maine. I’ll avoid the politics of all of this, but as it relates to gulls, it only makes sense that all of these white-winged gulls are following these boats out of more northerly Maine waters to Gloucester. The rarities are following as well, and/or are simply attracted by the masses of birds in and around Gloucester. Then, there's the "Cape May Effect" - lots of great birders birding an area and finding even more great birds. The occurrence of Slaty-backed Gulls, meanwhile, on the East Coast is an ongoing event – which my co-author Marshall discussed in our Changing Seasons essay in North American Birds (by the way, I’m still waiting for that to go on-line so I can offer a link here on the blog).

Gloucester.

On Sunday, we met up with my friends from NJ Audubon in Gloucester for a day of birding around the Cape. The Jodrey Fish pier, Niles Pond, and Eastern Point Light all held some Iceland and Glaucous Gulls, while a 3rd Cycle Lesser Black-backed Gull was also present on Niles Pond. But, no Slaty-backed Gull.

1st Cycle Glaucous Gull at the Jodrey Fish Pier.

Birding our way through Rockport, Pete spotted a Dovekie off of Bass Rocks. Although it took a little while, as the Dovekie was diving actively, we managed to get all 12 participants a look at this bird – many even enjoyed scope views.

After lunch, we continued on into Rockport when the phone rang. The Slaty-backed Gull was on Niles Pond. Two vans and our car did an immediate about-face and drove back to East Gloucester. So did the caravan from the day’s Brookline Bird Club trip. Both groups rendezvoused at Niles at nearly the same time, only to learn that the Slaty-backed had disappeared. A dozen or so Iceland Gulls, and a second Lesser Black-backed (this one a 1st-cycle) seemed small consolation.

While we were standing around the Pond, the phone rang again – there was a Thayer’s Gull at Eastern Point Light. So once again, the parade of vehicles moved in unison. In addition to the Thayer’s Gull, there was a very white, and very small-looking 1st Cycle Iceland Gull that is a candidate to be of the nominate subspecies, glaucoides – the “true” Iceland Gull. 100+ Purple Sandpipers roosted on the rocks of the breakwater, and there were plenty more Iceland and Glaucous Gulls around, but it was this one bird that garnered all of the attention.

Despite the low light conditions, I was able to get some semi-decent digiscoped shots. Here are the three extremes of the Thayer's/Iceland complex, from left to right: a "normal" Kumlien's Iceland Gull, the Thayer's Gull, and an extremely white individual - but all 1st Cycle birds.

A Thayer's Gull - whatever that means!

A very white Iceland Gull, that along with its small size, suggests an individual of the nominate subspecies "glaucoides."

Although somewhat pale for a Thayer’s – and therefore subject to debate, as all Thayer’s always are – the bird looked good to me. Pale brown primaries, and mostly pale brown tertials, with marbling limited to the outer ¼ or so (we would like to have seen those primaries to be a bit darker; a shade or two darker than the tertials, providing the “stepping stones” of darkness from the primaries to the tertials to the coverts). The dark smudge through the eye, and the wide, pale margins around the primary tips were important features, and in flight the dark secondary bar was readily noticed. Another birder on the scene snagged some fantastic flight shots, showing the “picket fence” of the outer primaries – dark outer webs and pale inner webs, contrasting with the overall paler inner primaries. And, the underwings were whitish. Overall, I thought that this bird was definitely a bit pale for a “typical” Thayer’s – whatever that means, as there are all sorts of taxonomic uncertainty about this group.

Those aforementioned flight shots, and a much better image of all three “types” of Iceland Gull that were all present on the rocks together, can be seen here.

With the New Jersey Audubon group heading back to Rockport, we parted ways, and Jeannette and I spent a little more time hoping for the Slaty-backed to return to Niles Pond. About 15 Iceland and 10 Glaucous were now present, but, alas, no Slaty-backed.

We estimated that we saw 30-40 Iceland Gulls, and at least 20 Glaucous Gulls this day (other birders, who carefully counted and estimated, concluded that 50+ Iceland and 20-30 Glaucous Gulls were present today – truly amazing numbers!)

On Monday, I began the day seawatching from Jeannette’s parents’ living room. It was raining, the wind was howling, and I was as warm and cozy as could be. Unfortunately, the winds were out of the south-southwest, so the seawatching was not very productive; an hour produced only one Black-legged Kittiwake (larid number 8 on the weekend!), one Razorbill, and one Northern Gannet, thanks to those winds and dense fog that significantly reduced visibility.

After a relaxing breakfast with the family, Jeannette and I returned to Niles Pond. There, a friend informed us that the Slaty-backed HAD been present this morning – although for only 10 minutes – but he had forgotten his cell phone. So, while we were enjoying bacon and eggs, he was enjoying the Slaty-backed Gull. At least 20 Iceland Gulls were present, but this was now of small - and rapidly diminishing - consolation.

Although there were thousands of gulls on Niles Pond, and I would have been happy to sit there all day and comb through the masses, but I was dedicated today to finding Jeannette’s life Slaty-backed, so we moved on, checking Eastern Point, breaking for lunch, and then returning to Niles Pond.

First, there was this gull, which will be left as “Gull sp.” The first rule of gull-ID is know when to say, “I don’t know,” and be able to walk away. This bird shows some suggestion of Thayer’s, but really just seems to be a wussy smithsonianus Herring Gull.

A first-cycle Thayer’s Gull – different, and “better,” than the one from last night was now present, and it nicely showed the gradation from medium brown wings, to pale brown tertials, to even paler brown marbled coverts, etc. (although these photos don't show that as well as it appeared in the field, in my opinion) Some good views of the bird bathing and in flight also showed the confirming flight feather characteristics. But, still no Slaty-backed.

This shot doesn't show much to be of ID value, but I just thought it was kinda cool!

We took Sasha for a walk at the Dogtown Common (8 Purple Finches was the highlight), checking the fish pier to and from. Checking Niles Pond and nearby Brace Cove once again, we happed to spot the pair of American Wigeon that had been found yesterday, and the American Pipit that has overwintered in the area. 11 Gadwall were at Eastern Point Light, our high count for the weekend, but once again, no Slaty-backed Gull.

On Monday, our third and final day of our trip, I was not going to take “no Slaty-backed” for an answer. After quickly checking Niles Pond, Eastern Point, and the Fish Pier, I grabbed some Dunkin Donuts hot chocolate and a folding chair, and sat down at Niles Pond, dedicated to waiting for the Slaty-backed, while Jeannette – spending a last morning with her Aunt – waited by the phone at the house.

There was one problem, however. Yesterday’s temperatures in the upper 50’s had resulted in an early ice-out (at least for now) on Niles Pond, and the gull numbers – that was at least 3,000 at one point – was now down to 18. A steady trickle of birds were coming and going – but my maximum count was 116, and only one Iceland Gull. Meanwhile, a female Ring-necked Duck had arrived, and two Red-winged Blackbirds were singing nearby, giving the morning a very spring-like feel. Again, this was no consolation.

After saying our goodbyes, Jeannette and I headed out, with one last stop at Niles Pond. Just a few dozen gulls were present, and Jeannette declares, “I’m done with this bird,” and so that was that. A Red-bellied Woodpecker was a nice treat at Ravenswood Park, but then we hit the road, heading north.

A late lunch at Loco Coco’s Taco in Kittery, was followed by a few stops along the Maine coast. A stiff west wind was not conducive to excitement at the Cliff House (19 Harlequin Ducks), and when we hit Wells Harbor for a walk at Community Park (ever since I found that Wood Thrush here last winter, I will stubbornly check this place over and over again, and likely not find a darn thing ever again!) and some marsh and river scanning, the wind was howling, a snow squall was falling, and the temperature was dropping. Ah yes, back in the great white north. And, no Slaty-backed Gulls were here either.