Loons begin a full body molt (minus their wings) in the late summer and early fall, prior to migration. The black and white breeding plumage of adult loons in summer is replaced by the gray-brown of winter. This process typically begins at the base of the bill and spreads across the head and over the upper back. The process of molting can extend through migration on into December.
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Looking as if it were stuck to the vertical cliff wall by crazy glue, a raven’s nest is often used for several years in a row. The nestlings remain in the nest for about 5 to 7 weeks, during which time they go from being an orange/pink color, sparsely covered with gray down, to the black plumage of an adult. The pictured nestlings are approximately five weeks old, and have just started to exercise their wing muscles in preparation for their first flight. They are panting with open beaks in an attempt to dissipate the heat of an unrelenting May sun. Within a week or two they will leave the nest, but will stay nearby for a few days. I couldn’t get close enough to give this nest a smell test, but supposedly raven nests can have an unbelievably unpleasant odor (due to the remains of leftover food/ carrion and feces).
Although the common grackle, a member of the blackbird family, is the bane of many corn growers as well as a threat to songbirds trying to raise young (grackles eat other birds’ eggs and nestlings), it is quite a colorful bird, with its pale yellow eyes and iridescent purple plumage. Grackles have already begun nesting and defending their territory, as can be seen from the stance of the bird in this image. This “bill-up display” is a position assumed when a male is being approached on its territory by another male. It moves its head upwards so that its bill is almost vertical, signaling to the approaching grackle that it would be in its best interest to depart.
Male red-winged blackbirds have returned to Vermont, and their most notable features are the brightly-colored reddish-orange feathers on their “shoulders”, referred to as epaulettes. In the military, an epaulette is a shoulder ornament that indicates, through its position, color, length and diameter, the bearer’s rank. Some birds, including male redwings, also possess this badge, or visual cue, which indicates the social status of the bird to other birds of the same species. Studies of male red-winged blackbirds and their epaulettes indicate (through dyeing their bright orange/red shoulder patches black) that epaulettes play a significant role in the male’s defense of his territory. Over 60% of the redwings that had their epaulettes dyed black lost their territories to other males. Further research revealed that aggression by a territorial male redwing is proportional to the epaulette size of the encroaching male redwing. It also indicated that male redwings intruding into redwing-occupied territories greatly limit the exposure of their epaulettes by covering them with black feathers. (Female red-winged blackbird plumage is brown and lacks epaulettes.)
Countershading is a common color pattern in animals in which the upper side of the animal is darker than the lower side. This color pattern provides camouflage for the animal when viewed from the side, above or below. The counter shading pattern balances the sunlight on the animal’s back and the shadow beneath the animal so as to blend the animal’s side profile with its surroundings. In addition, when viewed from below, a counter-shaded animal with a light belly blends into the light coming from the sky above. When viewed from above, the darker back of a counter-shaded animal blends into the darker ground colors below. Birds (which spend a considerable amount of time in the air) such as this dark-eyed junco, as well as marine animals often exhibit countershading.
Unlike their greenish-black iridescent parents, this year’s young European Starlings had a drab gray-brown plumage through the summer. During late summer and fall all starlings molt and black speckled feathers grow in. There is a brief period of time when juveniles still have a pale tan head, before it, too, becomes speckled. Even though both juvenile and adult European Starlings resemble each other by late fall, it is possible to tell this year’s young from adult birds. First-year starlings have more white speckles than adults, and their speckles are heart-shaped, as opposed to the V-shaped speckles of their parents.
Possibly because of the importance of summer fruits in their diet, Cedar Waxwings (Bombycilla cedrorum) are late nesters, but by late August adults have begun their migration to the southern states and Central America. This year’s young are beginning this (roughly) 900-mile flight now, a month after their parents have left. You can often find waxwings feeding in crab apple and other fruit trees where they stop over during their flight to refuel. Juvenile birds lack the sleek look of adults — the red wax-like feather tips for which this bird is named have not developed, and the color of their plumage is much duller than that of the adults.
This year’s Common Loon chicks are now roughly two months old. Even without being aware of when it hatched, you can estimate the age of a chick by looking at its feathers. Their color and type (down or contour) can give you a good idea of how many weeks old it is. Common Loon chicks are born covered with sooty-black down. By the time they are three weeks old they have replaced this natal down with a second (gray-brown) down. Juvenal feathers start appearing soon thereafter, replacing the down — the age of a chick can be estimated by the amount of down that remains. By eight weeks of age the chicks have just small tufts of brown down remaining on their head and neck (see photo). By nine weeks of age their entire body, including their head and neck, are covered with smooth, gray contour feathers and there is no sign of down.
Hardy birds that they are, Great Horned Owls are one of the earliest nesting birds — you can find them on nests in January, February and March, even in northern New England. Eggs are incubated for about a month, typically in March or April with young usually hatching in May or June. The nestlings remain in the nest for six or seven weeks before fledging. Unable to fly until they’re ten or twelve weeks old, the fledglings follow their parents around and continue to be fed and cared for by them until the fall. These two fledglings were sticking close together as they made their raspy begging calls from high in a white pine. Both their calls and the down that was visible on their heads told me that they were this year’s young.
The Red-tailed Hawk nest that produced two fledglings last year is in use again this spring. In the past month the nestlings have gone from tiny white powder puffs to nearly equaling their parents in size. Down is still visible, especially on their heads, but contour feathers are quickly replacing them on other parts of their body. Soon there will be wing stretches and flapping, as well as hopping about on nearby branches in preparation for fledging.
There is something irrepressibly cheery about the song of an Indigo Bunting. The male’s paired notes ring out from a high perch, where this unbelievably blue bird positively sparkles in the sunlight. According to Cornell’s “All About Birds” site, the male sings as many as 200 songs per hour at dawn and for the rest of the day averages a song per minute. To hear an indigo bunting sing, go to http://www.allaboutbirds.org/guide/Indigo_Bunting/sounds .
The Yellow-rumped Warbler (aka “Butterbutt”) has returned to our woodlands, and our ears and eyes are all the richer for it. The song of this bejeweled songbird often stumps me the first time I hear it every spring. It is described as a “slow, soft, sweetly whistled warble” or trill. It is also said to resemble the sound of an old-time sewing machine. To see which song description you prefer, or to make your own, go to http://www.allaboutbirds.org/guide/yellow-rumped_warbler/sounds.