Saturday, 6 August 2016

[Maine-birds] MACHIAS SEAL ISLAND REPORT

The age cracks are slowly appearing in Summer: lawns are growing more slowly; early migrants like the SHORT BILLED DOWICHERS have mostly come and gone; lots of plants are going to seed; 2nd (& 3rd?) broods of SAVANNAH SPARROWS are dancing and demanding food everywhere I look; most all of the fledgling Terns have moved to the shoreline loafing areas; young COMMON EIDERS are getting more and more difficult to distinguish from the adults; wandering species are showing up more often; the boat tours are into their last week or so and the Researchers are counting the days to their departure.

It's been a mixed year for the Alcid colonies.
 
MURRES probably did the best, followed by the RAZORBILLS with an "Okay" season.

 It's been a disastrous year for PUFFIN reproduction. Primarily, it's an issue of nutrition, with the poor food  quality and quantity yielding many dead Pufflings. Most of the living are severely undernourished, grossly underdeveloped and unlikely to survive.
Every night there should be fledglings appearing around the buildings and lawns, making their way to the water. On good nights we should capture several dozens for banding, bagging and a free rides to the shore. In normal years there would be hundreds banded before the researchers departed and lots of fledgling to go unbanded after the researchers departed.
I believe that only three (3) fledglings have been lawn-captured and banded this season, with one or two others see that were too underdeveloped to warrant banding.
It's the same story throughout the colony: chicks at and beyond the normal fledging age with the appearance of being half grown: weights of 150-170 grams instead of the more normal 300+grams and only partly feathered (8/10 count).
Puffling Preemies might not be quite accurate but it's the image that comes to mind.
Undoubtedly there are some youngsters that are doing well, whether through the experience and skill of their parents or good fortune in the foraging. Nonetheless, it looks to me to be, by far, the worst season in the 21 years that I've been here.

I'd describe the TERN season as a bit disappointing. Granted, last year's stellar season set a high mark and any breeding success is certainly far better than the Zero Decade. There was good nest numbers and a decent hatch but weather, and more significantly, food, played against the chicks.
The Terns experienced the same poor food as the Puffins. Chicks receiving food items such as Insects, Shrimp and Sticklebacks have been seen too often. Some have gone days without any observed feedings.
Many tern chicks are still more dependent on their parents than I like to see.

For example: One chick that seemed to be doing well, suddenly stopped receiving food although the adults were around. It was noticeably failing when, just as suddenly, food resumed.
It revived in spite of the low quality food quality but remains dependent and spends most of its time at the nest site. It's sitting there now, hoping to be fed. It's now around 50 days old, far beyond the normal 21-24 day fledging age.

Other chicks are following a similar road.
Fingers crossed but I question their ability to embarque on and survive the migration.

Still, it's not all bad news. Some of the chicks had good tickets in the survival lottery and look healthy and well developed.
I'm putting this year down as successful, albeit a bit disappointing.
The ARCTIC TERNS have managed to raise some young and it's likely that the few COMMON TERNS also produced heirs. Also, the colony functioned in a normal way, with the Terns displaying lots of aggression, chasing off interlopers and no inclination towards abandoning nests or young.

The BLACK TERN hasn't been evident lately. It had taken to spending time with the other terns in the intertidal zone.
Perhaps it has moved on. It's speculative whether it might have been a female, nesting with sterile eggs, like some past Black Terns.

SPOTTED SANDPIPERS seem to have had a low-normal season, with the COMMON EIDERS doing about the same.
SAVANNAH SPARROWS are well into their 2nd broods and some at acting like they have a 3rd family in development.
LEACHES STORM PETRELS are difficult to quantify but the impression is that they may be down slightly. They are still in the incubation/hatching stage, with upwards of 10 weeks of growth before they fledge in late September or early October.

Non-resident species have been sparse but usually persisting for several days.

The most recent bird of note is a mature LARK SPARROW which I first spotted on Thursday, August 4th. It's not a rare bird (we get a few every spring and fall) but this one is just a little earlier than others which I remember. It's also slightly more flighty, perhaps because of harassment from Savannahs with fledglings.

Overlapping the L. Sparrow was a female HARRIER that hung around for nearly a week, much to the displeasure of the Terns.

A few scattered RED WINGED BLACKBIRDS and at least one GRACKLE have been seen over the past couple weeks.

At least 5 RED BREASTED NUTHATCHES and possibly over a dozen were very evident during the latter part of this week.

I also spotted 3 different NORTHERN WATERTHRUSHES that were foraging among the outer boulder piles.

The shorebirds haven't been particularly impressive: smallish numbers and few species.
Recently observed:
SHORTBILLED DOWICHER (12, down from early season 60 or more);
RUDDY TURNSTONE (6-8);
LEAST SANDPIPER (50+);
SEMIPALMATED SANDPIPER (<50);
SEMIPALMATED PLOVER (<20);
WIMBREL (4);
SPOTTED SANDPIPER (5, presumed resident);
UNIDENTIFIED (<20).

HERRING GULLS & GREAT BLACK BACKED GULLS are about at their seasonal normal on the island with some expected predation. There are also sizable flocks using outer areas of this island and the adjacent Gull Rock as loafing areas and night roosts.

 These flocks are often in the thousands and show a large seasonal increase in both mature and immature Black Backs. Most of these gulls are likely attracted to the seasonal Herring seining that takes place a few miles to the South of MSI. 
These flocks regularly number three thousand and I've counted over seven thousand at times.

 Other than the resident Eiders, ducks are few and far between, usually only an occasional RED BREASTED MERGANSER.

Rarely, there's an early COMMON LOON, with the more usual large diver being scattered DOUBLE CREASTED CORMORANTS.

Lastly, GANNETS are occasional fly-bys but none seem inclined to stop on the island. Quite likely the birds we see now are not those which attempted nesting. Hopefully, those birds will be back next spring and be more successful.

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