Sunday, November 29, 2009

Melanistic Black-capped Chickadees in Aroostook Co


Presque Isle birder, Sue Pinette, recently forwarded a couple of interesting bird pictures that she'd received from her friend, Susan Chandler. Sue C. had a small dark bird visiting her yard on the northeast side of town and got a couple images of the bird when it visited her feeders.

As you know if you read the title of this post, I believe the mystery bird is an unusually dark plumaged Black-capped Chickadee. A quick summary of the pertinent characteristics is probably in order to support this identification....

First, thanks to Sue's nice, clear shots, it was easy to get a good look at the bird's plumage: the bird had an all dark head, a dark gray back, wings and tail and a slightly lighter gray underside. The eye, beak and feet were also black.

This late in November there are a few bird species in northern Maine that look somewhat similar to Sue's bird. But the apparent best-fit is probably the Dark-eyed Junco. So this species should be compared with the bird in the photos. The junco is small bird with a dark head, dark gray back and a dark eye- like the bird in the pictures. Unfortunately, the similarities end there. Juncos also have a clean white belly and white outer tail feathers and a light pink bill. None of these were visible on the bird in the photos.

Though the plumage doesn't match any local bird species, before considering more exotic bird species we should look for subtler clues to the birds identity... Judging the bird in comparison with the feeder and sunflower seeds inside, its evident the bird is a small one. Looking at the bird's shape is helpful. The bird is stocky with a blocky head and short stout bill. The second photo shows the bird with a single seed and apparently ready to fly from the feeder.

All of these point to one of the commoner species around feeders in northern Maine these days: the Black-capped Chickadee. I'm sure if we could watch the bird flitting back and forth from the feeder to the woods and hear it vocalize we'd be able confirm this ID.

It appears Sue's mystery bird is an unusually plumaged chickadee possessing an abundance of the dark pigment melanin. This extra pigment causes areas that are normally light or white to appear black or dark gray. These melanistic birds are substantially rarer than the opposite form of aberrant albinism. Here is a look at a normal plumaged Black-capped Chickadee taken at my Woodland feeders for comparison with these dark ones.


Even though I tried to explain how I could come to the identification of Sue's bird above, in truth, I jumped to this conclusion fairly quickly. This wasn't because of any great insights on my part, but actually because there have been several dark chickadees reported in the northeastern parts of Presque Isle in the past ten years or so. I've sorted my way through this ID before!

Roberta Griffiths first reported an all dark chickadee at her feeder back in 2003. The bird stayed at her yard most of that winter and she was able to get a video of the bird and in the recording one can hear it give the classic Chick-a-dee-dee call of the Black-capped.

More recently, Roberta also brought me the photo of a dark chickadee seen here taken at a feeder on the Parkhurst Siding Road in Presque Isle. The picture was taken in January 2008. While not quite as dark as Sue's bird and certainly not all black, the bird also has an all dark head like the others.



Here is a cropped version of the same picture:

Though the observations of these melanistic chickadees were made in locations that are only a couple miles apart in the north eastern side of town, the span of time (7 years) and the apparent difference in relative degree of pigmentation would seem to indicate that there is a small population of melanistic chickadees in Presque Isle. I'm not sure but I don't think this has been reported before.

Though extremely rare, melanism in chickadees has been reported before. James Tanner (the famed Cornell ornithologist who filmed Ivory-billed Woodpeckers back in the 30's) found one in up state New York in 1933. His paper on the discovery can be found online here:

http://elibrary.unm.edu/sora/Auk/v051n02/p0240-p0240.pdf

Alfred Gross, a Bowdoin College ornithology professor, wrote about the rarity of melanistic birds in an article for the Journal of Field Ornithology in 1965

http://elibrary.unm.edu/sora/JFO/v036n04/p0240-p0242.pdf

Good stuff indeed

Monday, November 16, 2009

Northern Maine Birds 1-16 November 2009

Sunday's rain broke a two week dry spell in northern Maine. The weather has been balmy with warm temperatures for the season. Very little bird movement seems to be going on.

Passerines are in short supply and the general report is that feeding stations are slow.

Waterfowl numbers waned in late October thanks to cold temps, some heavy snow and frozen conditions on smaller ponds and wetlands. Geese numbers rebounded nicely as it warmed in the first week of November and a pulse of apparently "new" geese moved into the area. Canada Goose numbers have held around 12-15,000 in the central Aroostook area and flocks of over 3,000 birds are being seen at Collins Pond in Caribou, Lake Josephine in Easton and a private ponds in a couple Presque Isle locations. Paul Cyr photographed the scene at Collins Pond recently. Dozens of smaller flocks are being seen in other locales. With the exception of a couple Snow Geese seen on the 10th, none of the rarer species of geese have been seen this month. The Cackling Goose reported at Collins Pond in October was seen once more on the 26th and not again

Ducks have been in short supply since the October cold snap. Among those remaining, the most notable ducks were found at Lake Josephine as usual. Five Long-tailed Ducks was a high count here on the 2nd, but these had dwindled down to a single male by the 10th. The bird was in (what I believe to be unusually late) dark brown, breeding plumage. A White-winged Scoter had replaced the Long-tail on the 11th. Other good finds here was a lingering Gadwall, female Bufflehead, two Redheads and a Greater Scaup among 8 Un-ID'ed scaup on the 10th. 11 lingering Ring-necked Ducks continued here through the 16th. On the first a pair of uncommon Greater Scaup were seen in the mouth of McLean Brook at Sinclair and three bright male Buffleheads were on Long Lake at St. Agatha.

Large flocks of Common and Hooded Mergansers are being seen on the larger impoundments. Christina Reservoir at Fort Fairfield had high counts with 180+ Hooded Mergansers and 140+ Common Mergansers on the 3rd.

A single Double-crested Cormorant lingered late to the 10th at Christina Reservoir.

Ruffed Grouse were reported (and in some cases savored) at many locations. Though a likely release, this male Ring-necked Pheasant was none-the-less noteworthy and photographed in Fort Fairfield by Paul Cyr.

Christina's Merganser flock attracted the attention of Bald Eagles and as many as four adults and two sub-adults have been hanging around the pond. An adult Northern Goshawk was seen briefly on the Muscovic Road in Stockholm. Still uncommon in northern Maine, Red-tailed Hawks seen in Sherman on the 12th and Presque Isle on the 13th were almost as notable as a Rough-legged Hawk seen in Limestone on the 10th.

The only shorebird found in the area was a very late White-rumped Sandpiper seen on the 16th. The bird was flying over the shore of Lake Jo and would gone un-identified, but luckily, the bird vocalized and its high pitched squeak revealed its identity.

Gulls continue to move through the area and large concentrations are being seen a Long Lake, Collins Pond in Caribou and Echo Lake in Presque Isle. A high count of 192 Great Black-backed Gulls at Collins Pond was noteworthy. A first cycle Iceland Gull was associating with a few Herring Gulls here on the 14th.

A few Ring-billed Gulls continue to hang out in the area. Almost all Hooded Merganser flocks are being attended by at least a few of these gulls. The Ring-bills watch the feeding ducks and move in to steal food from these just as they surface with their meal. On Veterans Day, I watched Ring-billed Gulls deftly relieve a drake Hoody of a couple fine, large crayfish here at Collins Pond.

As noted earlier there are low numbers of passerines (the small perching birds) being reported in the area these days. It is unclear whether the birds are enjoying plentiful natural food supplies and aren't coming in to visit feeders, or the bird are just in short supply at this time. From my recent time spent birding in the very quiet woods, I suspect the latter.

Woodpeckers are a bit of an exception and the birds are being seen in "normal" numbers. Noteworthy among these, a Black-backed Woodpecker was found just outside of Aroostook NWR at Malabeam Lake in Limestone on the 11th.

The first Bohemian Waxwing flocks of the season were spotted around Presque in early November. Thirty were gobbling up high bush cranberries near the airport on the 4th.

Golden-crowned Kinglets were well reported during early November with small groups heard at Caribou, Limestone, Presque Isle and Woodland. Black-capped Chickadees have been reported to be in short supply around many of the areas feeding stations at this point in the season. However large foraging flocks are being encountered in the woods. The antics of a single feeding group of 22 chickadees was enjoyed in the woods in Caribou on the 11th.

Red-breasted Nuthatches are also well detected in the otherwise quiet woods. These birds nasal vocalizations are often the only bird calls heard these days.

A White-breasted Nuthatch and a Brown Creeper were a rare treat in Fort Kent on the 14th. These two uncommon birds were found feeding on the big silver maples along the shore of the St. John River, at times creeping along the same trunk. Paul Cyr got this nice shot of the fidgety creeper. Another creeper was seen later that day in the Woodland Bog, possibly indicating some movement of this rarely-found species through northern Maine.

Blue Jays have been dominating my feeders for over a month and others are reporting similar activity. Paul Cyr sent over this great action shot of some squabbling jays at his feeders in Presque Isle. I've only found two Gray Jays recently. One showed up at my freshly hung suet feeder in Woodland on the 11th and another was calling from the bog off the Muscovic Road in Stockholm.

With the exception of Snow Buntings, I have not seen any of sparrow family in over three weeks! Early Dark-eyed Juncoes and American Tree Sparrows seem to have pushed quickly through during the October cold snap and the snowstorm on the 25th really cleared them out.

A few of the "winter" finches are being encountered in the woods but I've yet to hear of much action around feeders. A Pine Grosbeak was heard and several flocks of White-winged Crosbills were seen over the Muscovic Road on the 14th. Again Paul Cyr was there to catch at little of the crossbill action... Purple Finches are occasionally heard flying overhead but do not seem to be about in any number. A few Pine Siskins are visiting a feeder in Presque Isle.

American Goldfinch numbers seem to be building a bit recently and are starting to show up at the thistle seed feeders.

A lonely Evening Grosbeak was calling as it passed high over my house in Woodland on the 8th.