September 5-6 Bird Sightings; World Shorebird Weekend
Outer Green Island
World Shorebird Day was September 6, and it was celebrated over the entire weekend (1). To honor the shorebirds we venture out to the outer islands in Casco Bay – hoping to catch a glimpse of them. Our first destination is Outer Green Island, usually visible from Peaks Island Backshore except when the fog rolls over it. In the winter it is covered in ice. From April 1 to September 1 it is green with little tents perched on it where National Audubon Society personnel set up camp to monitor and protect nesting water birds, and public visitation is prohibited. These birds include Arctic, Common, and Roseate Terns, Black Guillemots, and Common Eiders. (2)
Is anyone curious about this little island? We are. It is after September 1, so the breeding season and Audubon’s monitoring season were over. We set out, and although the seas are calm with little wind, the water below us moves – an eerie energy – making the island approach even more mysterious.
Outer Green Island is a surprise. From Peaks Island it looks like one long island with two flat table tops connected by a low isthmus - holding it together - at low tide. The small southern ‘table top’ is actually Junk of Port, setting off to the east of Outer Green Island.
Junk of Port at Low Tide
At one time they were connected (3). Junk of Port is a towering rock eroded by surf – sinister in appearance, yet, a safe and high haven for Double-crested Cormorants, and a place to dry their wings.
Double-crested Cormorants on Junk of Pork
We look forward to a hike along Outer Green Island trails created by the departed summer staff. But this island is Maine-rugged with steep cliffs and jagged rocks that extend from its shores; they are formidable. We find a cove and landing is possible, but leaving the boat is not a good idea. As small swells roll into the cove, Sam holds the boat off the rocks, so that I might get a quick peek.
Cove on Outer Green Island - "Sea Parrot and Sam"
What was once (only a month ago) camp sights, blinds and an outhouse – are now overgrown by tangled vegetation – inhospitable - with no trails.
The cliffs are steep, but along them are little pink flags marking what were tern nesting sites – at one flag is an un-hatched egg – perhaps one of the Common or Artic Terns as their eggs are nearly indistinguishable (4).
We observe Double-crested Cormorants, Great Black-backed Gulls, and Herring Gulls resting on the cliffs and rocks. A juvenile Bald Eagle soars over the island. The gulls immediately leave their rock perches, followed by the cormorants. We are surprised that the eagle intimidates the gulls, more so than the cormorants. The Great Black-backed Gull is the biggest of gulls (length 30 inches, wingspan 65 inches, and weight 3.6 pounds), yet it is bullied by the young eagle (length 31 inches, wingspan 80 inches, and 9.5 pounds [5]). A large flock of 200-300 female and juvenile Common Eiders also rush away from the eagle.
Female and Juvenile Common Eider Flock
Several Black Guillemots - a non-breeding adult and two juveniles, in their grey plumage - are fishing along the northern rocks.
Black Guillemots, Grey Plumage
We drop anchor for lunch at the northern end of Outer Green Island, where we are surprised by shorebirds flying onto the rocks – just next to us. We see Ruddy Turnstones and about 6-10 little peeps (Semi-palmated Sandpipers?) feeding on the seaweed-covered rocks – perhaps finding edible invertebrates, after their long journeys from the North latitudes.
Ruddy Turnstone
Semi-palmated Sandpipers (?)
Between Inner Green Island and Jewel Island we see a large flock of eiders – 150-200 females and juveniles. On Jewel Island we find the largest tide pool in Casco Bay – The Punch Bowl. It is on the ocean side – there we closely examine a plankton tow and we find several species of copepods, a tiny crustacean critter that provides a tasty morsel for foraging water birds. A Great Blue Heron and a Spotted Sandpiper were foraging there.
Punch Bowl, Jewel Island
We set course for the beaches of Long Island in search of more shorebirds, but a little alluring island off Long Island (Vaill Island) sidetracks us. Moored in its cove is a motorboat, Elmo, with a party of people enjoying a beach picnic. We choose the other end of the cove. As we approach the beach, we see little shorebirds along the dead seaweed line. We carefully pull ashore, trying not to disturb them. They are unaffected by our approach. We watch as they feed on little invertebrates and preen, sometimes within a few feet of us. Then, spontaneously, each one plops down on its belly and closes its eyes in sleep - camouflaged nicely in the dried seaweed. We identify Semi-plamated Plovers, Least Sandpipers, and Semi-palmated Sandpipers.
Approaching Vaill Island
Semi-palmated Plover and (?) Peeps
(?)Peep, Least Sandpiper [note yellowish legs], Semi-palmated Plover
Semi-palmated Plover and Semi-palmated Sandpipers (?)
Sleeping Plovers and Peeps
Leaving the napping shorebirds we explore an inland mudflat surrounded by marsh grasses: Phragmites sp. (freshwater/brackish water tolerant), Scirpus sp., and Spartina patens (saltwater preference) – the presence of Phragmites suggests that some fresh water exists here. As we return to the beach we hear the shorebirds peep, as they are flushed by members of the picnic party approaching us. They summon us. Maybe we are trespassing? No, they need help – their dinghy floated off island with a defunct engine and man aboard. With one member of their party, Sam’s searches and then locates the dinghy, tows it to Elmo, and delivers the 14 people and gear to Elmo, and they motor off to Portland.
Rescue of the "Elmo's" people
The shorebirds are gone.
These shorebirds remind us of other fatigued-migrating shorebirds. We recently observed Greater and Lesser Yellowlegs, and peeps at their coastal stopovers in the mudflats and marshes of Connecticut (6). They were so tired from their flights that they too plopped and nearly collapsed - sometimes hidden behind small objects on the mudflats, atop a floating wooden board, or on stranded-in-the-mud tree trunks.
Mudflat "Peep" Western Sandpiper (?)
'Peeps' Mud-flat Bunker
Lesser Yellowlegs on Floating Board
'Peeps' on Stranded Tree Trunk
Despite their small size they carry with them all the equipment they need: their feathers for protection, their little wings for propulsion, their small beaks to probe for food, and some mysterious inner radar (no iPhone GPS) guiding them to their destination. It is so humbling. Bags and bags of ‘stuff’ are standard for any of my road or air trips. They carry nothing.
Most shorebird species in our hemisphere select the Arctic regions of Canada, Alaska, and Greenland for their breeding grounds. They return to the southern states, West Indies, Central America and South America for the fall and winter. Late summer and fall migration strategies vary among species. For example, large flocks of Semi-palmated Sandpipers make stopovers after very long flights; the Least Sandpipers move across the continent to the coasts in broad fronts; and many Western Sandpipers make short stops crossing the continental US to the Atlantic coast. [Since the Western Sandpipers breed along the Alaska coast, why do some cross over to the East and Gulf coasts?] Generally adult females leave their breeding grounds first, followed by the adult males and later the juvenile birds (mid-August to October). So are the peeps that we are seeing in September, mostly juveniles - making identification even tougher? Despite their different flight strategies and their choice of when to put down their landing gear, they all rely on a rich source of food and a safe haven at their stopovers during their long migrations. (7)
Returning via Evergreen Landing we see a Common Loon, with a broken lower beak. Last winter Andrew took a photograph of a Common Loon in Casco Bay – it too had a broken beak – its lower mandible (February 2015 blog). This September loon is still in its breeding plumage whereas the one seen in Andrew’s photo was in its winter plumage. Perhaps it is the same loon? We would like to think so – that it has survived, and perhaps bred and raised a young loon, even with its handicapped beak.
Common Loon Photo © Andrew Jackson
We cross Diamond Passage and stop at Cow and Great Diamond Island. A month ago we saw four young Ospreys on the nest at Cow Island – now one Osprey remains – calling, with no return calls. Is it the youngest juvenile, or one of the adults?
Osprey, Cow Island Nest
And, the only evidence of the Barn Swallows nesting under the dock in Diamond Cove – is an empty nest.
Empty Barn Swallow Nest, Diamond Cove
We notice a “V” shape formation of dark flying birds – we believe they are Double-crested Cormorants starting their migration south. Even though many of our summer residents have left or are leaving, we look forward to the return of our winter residents.
(Please note Cornell Laboratory of Onrithology’s website – eBird - for seasonal observations of birds in our area [8].)
References:
Outer Green Island is owned by the Maine Department of Inland Fisheries and Wildlife (MDIFW) and is managed by the National Audubon Society (Project Puffin) and MDIFW with logistic support from the U.S. Fish and Wildlife Service, Gulf of Maine Program.
4. Reed, C.A. 1965. North American Bird Eggs. Dover Pulications, NY. Pp.40-41.
5. Sibley, D.A. (2000). National Audubon Society: The Sibley Guide to Birds. Alfred A. Knopf, Inc. NY.
http://www.ct.gov/deep/cwp/view.asp?A=2723&Q=326132
7. del Hoyo, J., Elliott, A., and Sargatal, J. eds. (1996). Handbook of the Birds of the World. Vol. 3. Lynx Edicions, Barcelona. Pp: 425-525.
Other Information:
Written and photographs (except where otherwise noted) by Patty Wainright
Reviewed by Sam Wainright, Michelle Brown, and Marty
Contributions by Michael LaCombe (eBird information)
Thank you for your interest in the PILP Bird Blog. If you have any comments or questions please contact Michelle at: brownmichh@aol.com
