Friday, December 4, 2009

November - Autumn's Turning Point

November means two things to Cape May birders; it means the impending end to autumn migration and it means the possibility of a major rarity turning up - a bird that really should be anywhere other than at Cape May.

Dawn in November sees the sun rising over a misty Lighthouse Pond. (Remember you can click on any picture to get a bigger version)

A November dawn reveals an empty parking lot at Cape May Point State Park and mist hanignig over the damp grass.

Autumn into Winter
Fall colour of leaves in Cape May County reaches its peak around the third weekend of October which is about the same time as it does in the UK. As the leaves start to fall off the trees, bare stems wave against a backdrop of ever greyer and ever more moody skies - winter is on its way. Frosty mornings and dawn mists bring a real chill to the air, but some days remain sunny and the air is clear, making for some really nice birding weather. It's under these conditions that our winter visitors start to arrive. Whether it be diminutive Northern Wrens creeping mouse-like through the woodland undergrowth or boisterous flocks of geese on the backbays, winter's birds are moving in to stay a-while.

Tiny, toy-like Buffleheads move in to winter on the backbays of Cape May and really do look like they should be floating among the suds in the bath!

Almost un-noticed, the vast majority of Laughing Gulls drift off south for the winter, eventually to be replaced by Bonaparte's Gulls which breed much further north. As I write in early December, few of these birds have arrived yet as the weather has generally been pretty mild, bit I found this one at Corson's Inlet on November 6th.

A touch of home from home. A Northern Wren moves in to our yard for the winter. The wren family has a mass of species in the New World - some 76 at the last count - but only one has made it to the Old World. Clearly the family evolved in the Americas and it seems likely that this little chap crossed into Eurasia via the Bering land bridge, in the dark and distant past when North America was joined to Siberia. In North America this bird is known as Winter Wren. Now, many will argue that this is a sensible name for a bird that is a winter visitor, but even in North America it is a winter visitor to less than 50% of its range. You see, it was named by people who live in the Eastern US, where it is a winter visitor. In Canada, this species is almost entirely a summer visitor, except for along the milder Western seaboard; throughout the majority of its Old World range, it is resident or merely a localised migrant. An alternative name of Northern Wren was suggested many years ago and, as this is an eminently sensible name, it is the one I will use!!

Flocks of Dark-eyed Juncos up to 60 strong fed around Cape May during November and a few will stay for the winter, with others moving on further south. An unassuming little bird, they nevertheless have great character with their soft grey plumage, pink bill and flirting white outer tail feathers.

At Cape May, birding excursions move from the fields and woods in the centre of the peninsula to the backbays and beaches of the barrier islands and to the stone jetties that protect the coastline from longshore drift - the process by which the Cape May peninsula was formed in the first place.

Cold Spring Inlet jetty, as seen from the far end!

Some of the stone jetties around Cape are long enough for the brave and adventurous birder to get right out amongst the birds. The Cold Spring Inlet jetty (which protects the main entrance to Cape May Harbour itself) is some 400metres long on the Two Mile Beach side of the inlet and, save for a few hardy rod fishermen, is a great place to get away from it all and get close to seabirds. With Northern Gannets and Red-throated Loons passing close to shore at this time of year, I even found that I was getting these birds passing between me and the shore, making for good photo opportunities.

A Red-throated Loon comes at me from behind!

Another Red-throated Loon gives a nice broadside view.

During their first year, Northern Gannets have a completely brown plumage and it takes around four years before they attain the classic black-and-white plumage of full adulthood. This bird is typical of a second-calendar year bird (ie hatched in summer 2008).

An adult Northern Gannet with mostly white plumage, black primaries and yellowish head. Note, however, that this bird has one or black secondary feathers left in its wing and is therefore probably a fourth-calendar year bird. Many individuals attain full adult plumage in their fourht year, but some drag it out an extra year!

Adult Northern Gannet.

The stone jetties are, of course, entirely artificial, having been constructed using huge boulders that are shipped in from other parts of the continent. Thus, they provide a habitat which otherwise would not exist in Cape May and attract several species to winter here that might otherwise be scarce visitors at the very most. Most immediately obvious of these species are the Purple Sandpipers that prefer the rocky coastlines of New England as a wintering site. For the sandpipers, as for the marine algae and invertebrates that live there, there is little difference between the natural, rocky coastline of New England and the man-made stone jetties of New Jersey, so now they come in good numbers to spend the winter here. The stone jetties are attractive to mussels too and these in turn attract birds that feed on them - the seaducks. As someone who has spent the last 25 years living in East Anglia and getting used to seeing scoters and eiders as distant blobs, bouncing up and down on a choppy sea some half a mile from shore, Cape May was to come as a pleasant treat! The stone jetties that provide them with food bring them close in to shore and offer great opportunities to study the differences between the three species of scoter that regularly occur.

Purple Sandpipers at Coldspring Inlet.

Black Scoters off St Mary's Jetty, Cape May Point.

Adult males of the three scoter species are essentially black ducks with or without small areas of white and it's the distribution of white, coupled with the bill pattern, that separates them. Black Scoters live up to their name and are, well, black! Their most attractive feature is the glowing orange beacon that they wear on their noses!

I'm still working on getting better photos of male scoters, but here I managed to capture all three species in one shot. At far left is a Black Scoter with all black plumage and orange beacon; fourth from left is a male White-winged Scoter with a white flash surrounding the white eye. At far right are two male Surf Scoters. The two bold, white patches on the heads of Surf Scoters has earned the species the name of 'Skunkhead' locally - a great name!

Female scoters are mostly chocolate brown and it's the pattern and distribution of paler feathers on the head that identifies them. (Juvenile/immature males look like the females in plumage, but during the first winter start to acquire colouring on the bill and darker feathers). This is a female Black Scoter which shows pale across the whole of the cheeks and face, resulting in a dark-capped look.

Female Surf Scoters have a dark vertical band on the face, which splits the pale feathers into two distinct patches. Actually, this is a juvenile/first-winter bird as adult females have a white eye, like the adult males.

A White-winged Scoter between two Surf Scoters. Again these are all first-winter birds so may be male or female but adult female plumages are similar. These two species can be difficult to tell apart as they have very similar plumages, but look very carefully at the bill structure and how the bill meets the feathering of the face. On the Surf Scoters, the bill is squared off at the base, giving a straight leading edge to the white patch on the front of the face. On the White-winged Scoter, the feathering extends further forward into the concave trailing edge of the bill. Thus, the pale patch has a rounded front edge. With views as good as this, the white wing patch of the White-winged Scoter is obviously a good pointer too, while having the two species side by side shows the Surf Scoters to be a little smaller and having a more rounded head.

This autumn has also seen an unprecedented influx of Common Eiders into South Jersey; according to David Sibley's The Birds of Cape May, the highest count of Common Eiders for the county in a single day was 26 on November 14th 1996. This year, three Common Eiders unexpectedly turned up off Cape May Point, not far from the lighthouse; gradually the number was added to and by late November, a single flock of some 180 birds was present, with a total of over 200 birds recorded around the point as a whole. In addition, well over 200 Common Eiders have been counted at the stone jetties up at Barnegat Light in Ocean County. Just why this is happening, no-one yet knows, but it does give us plenty of opportunity to study these birds and especially their protracted moult cycle.

Two of the first Common Eiders to appear off Cape May Point this autumn - an immature male in the front and female behind.

Common Eiders with a female Black Scoter.

Common Eiders off Cape May Point. Typically for birds outside of their normal range, the vast majority of these are juvenile or sub-adult birds. Note that all the males bar one (centre) have patchy black feathers masking their plumage.

Common Eiders off Cape May Point.