Saturday, October 30, 2010

maybe it is a Chandeleur Gull

I've been pooh-poohing this bird for at least 4 years now as having any Kelp Gull genes, believing Greater Black-backed to be the dark-mantled parent. Yesterday (a year to the day that I last featured it in a Tiscornia blog), the bird re-appeared at Tiscornia so Tim and I walked down after a bit to get some shots. It flew back and forth a few times so these are my first decent spread wing shots.

The bird, as usual, is in wing moult, with P7-10 retained from last year, P6 growing out, and P1-5 fresh. I think no more than a couple of secondaries are moulted, and obviously it's missing some inner rectrices as well. Note that on the outer retained primaries, the white tips of the feathers are essentially worn off.

Having pulled back up the Dittman and Cardiff paper describing the Herring x Kelp gull pairings in Louisiana's offshore Chandeleur Islands, the wing pattern does turn out to be pretty good for Chandeleur gull. Here's their description feather-for-feather with my feelings on this bird:
P10: black with a large square white mirror - yes, though maybe I wouldn't describe this bird's mirror as large
P9,8: black outer web and somewhat paler inner web - yes
P7: black outer web extending nearly to the base - yes
P6: black outer web extending partially up the feather, with the inner web dark gray and with a black subterminal band with a white tip - all those features present but this bird has a white pearl/crescent proximal to the subterminal band in addition
P5: dark gray with a black subterminal spot/bar, with a proximal white crescent above on the inner web and a large white tip - yes almost exactly, though a tiny amount of white in the pearl/crescent area is on the outer web too
P4-1: dark gray with a large white tip - this bird also has a small black subterminal band on the outer web of P4 and P3
Our bird has a little more white where Slaty-back has its "string of pearls" with some extra white on P6 and P5 for their description of a classic F1 Chandeleur gull, but overall that's pretty close, and a little more black spotting in P3 and P4, though Herrings certainly can be somewhat variable in how many of those feathers have black spotting too.
The 2nd flight shot does show the grey/green/yellow leg color which I still say sometimes looks pinkish in the webs in some lighting though Tim says I'm crazy (or need new glasses). Or both.
One of my biggest concerns about this bird in the past is that it does seem a little bigger than most Herring gulls, though in some of my pics it seems like it's longer but maybe leaner too. Since Kelp Gulls are smaller than Herring's I thought that would be a bit of a deal breaker, but perhaps not. Dittman and Cardiff say that Chandeleur gulls look about the same size as Herring gulls which the pics perhaps suggest.
Here's another of Tim's pics showing the size comparison as well.
So I guess the bottom line is that perhaps I am coming around to think of this as a Chandeleur Gull.

Just in case flight shots of black and white wings are giving you headaches, these Snow Buntings that swirled around us yesterday as well may be a bit of a relief on the eyes.




Wednesday, October 27, 2010

Cave swallows

According to my spreadsheets, today is the 100th day this year I've visited Tiscornia, and it was a pretty exciting visit. Fall low pressure systems commonly pull Cave Swallows out of their post breeding dispersal from the plains well into the midwest, and we weren't surprised that the current powerful one is producing them. We thought our best chance might be after the winds settle somewhat later in the week. I had 3 appear in front of me not long after I arrived, on me as naked eye birds before I was ready. All I could see were buffy throats that bled into the breast through bins. About an hour later 2 more birds appeared. These 2 we picked up well to the north and tracked them as they came past. I knew after experiments earlier this summer that you have to manual focus swallows as they're too small and fast for the autofocus, but I didn't listen so my pics are poor at best. I think the left bird is identifiable. Tim manual focused and got sharp images. It was somewhat of a strange day. Cave swallows are more typically November birds in Michigan. This Short-eared Owl was the only real typical October bird.
The rest of the migration felt like September. The bulk of the ducks were teal and dabblers; blue-winged's usually peak around Labor Day but they were the most common duck today. We also had 10 shorebird species including things like Baird's that's usually much earlier. A golden plover was my 3rd yearbird of the morning.

I'd like to know what the trail high duck is behind this group of redhead and canvasback.
Surf scoter would be more likely than harlequin duck, but the bird's size in comparison to the redheads makes me think twice.

I only had to wait for one wave to make a big crash in front of the lighthouse. Any amount of effort probably would have netted a pic with the spray above the level of the lighthouse.
Let's just say it was windy.




Tuesday, October 19, 2010

A birds gotta eat

The kinglet may have escaped the other day. This Winter Wren didn't.

A couple of the last few times I've been to Tiscornia the Merlin has been sitting up in its snag eating a passerine. I drove around this morning to use the car as a blind so that I could get some pics in the early morning light. The headless passerine appears to be a small brown bird with a short tail and some barring to the wings/flanks, I thought house wren initially but Tim pointed out Winter would be far more likely and looking at the pics full size on the computer I agree.
Falcons tend to pluck their prey...

... the feathers flew off in the stiff West breeze.

Sometimes it didn't have it anchored in its feet quite strongly enough, tugging it out of its own grip. It seemed odd to watch a raptor holding prey in its mouth.

I think this is probably a juvenile male based on the dorsal view (which I should have put up instead of this last photo) showing a bluish tinge to the upper back and that the tail bands on the upper tail are grayish, but per Pyle not all are age- and sex-able in fall. Wheeler wasn't terribly helpful in discriminating either.

Most years peregrines are much more likely to hang around Tiscornia, but this year they haven't been; perhaps that's why the merlin is sticking. The one-legged Piping Plover that's been hanging out a township to the south after originally being found in New Buffalo had better not come back any farther north...



Wednesday, October 13, 2010

Catch and release

When I arrived at Tiscornia this morning the wind and water were so (almost disconcertingly) calm that you could hear the whuff of airflow through the feathers of a banking merlin. It made a couple sallies out over the lake and I locked on to it as it circled after a small passerine.
After a few circles and misses, it banked its wings and cut off its quarry, snatching it without the feather-scattering impact that Coops have when they ambush the feeders.
The merlin latched onto its prey with both feet, steadying it to deliver a the final blow
but dropped the bird as it apparently tried to re-position it and the quarry escaped...
The merlin flew back to its snag and the passerine flew straight for the first tree it could find, the one I was standing under at our overlook point, a Golden-crowned Kinglet.
The bird remained perched on the branch for the better part of 30 minutes, re-gathering its wits before disappearing over the edge of the dune, having somehow escaped me having to title this post Requiem for a Kinglet.

The winds had picked up and about 2500 ducks flew past over the ensuing 3 hours or so, most of them scaup, before a long storm front halted migration, though not before Tim spotted my long-awaited Tiscornia life Bald Eagle.
I'd seen an eagle once from the brick road into the park, but never from the park itself.





Saturday, October 9, 2010

The right men's sparrows

That's right. Plural. All hail Berrien (if not the Victors). Good thing I spent the second half of the Sparty game in a sparrow field we've been checking.

The evening light brought out some of the warm dark tones of Nelson's Sparrows, even if they're not quite as bright as they are in May.
I don't think this picture has been taken too many times in Michigan (I know Tim has done it before), two Nelson's in the same frame.

After a quiet morning at Tiscornia we walked another field that's been productive over the years, and had at least 3 LeConte's, much paler buffier birds.


We were surprised to have one of the LeConte's fly up into some of the brush as well as disappearing into denser grass in places as well.

As for the locations, we-ell, I'm not really at liberty to divulge... ...sorry.



Saturday, October 2, 2010

The wrong man's sparrow

It's October in Berrien, which means it's time to look for eponymonic ammodramids, LeConte's and Nelson's. This afternoon I walked a little weedy patch close my house during nappytime.

Lincoln's sparrow, with a warmly washed finely streaked breast, could vaguely suggest a LeConte's as it hikes itself up a weedstem, though not once you look at the face (or when it flies away).
The Lincoln's were fairly responsive to pished imitations of their call notes.

This not so Indigo Bunting was also not the sparrow I was looking for,

nor are the Yellow-rumps that are now dominating warbler migration.

A Cooper's flew in, took a shot at one of the sparrows and it was time to go.