A tell-tale sign of Yellow-bellied Sapsucker activity is the presence of rows of 1/4–inch holes, often drilled in Sugar Maples and birch trees in order to gain access to their nutritious phloem sap. Once the sap begins to flow, sapsuckers insert their tongues into these holes. Here is where their name is misleading, as sapsuckers don’t actually suck the sap, they lap it up with the aid of tiny hair-like projections on the edge of their tongue, which hold the sap by capillary action (see insert). Each flick of the tongue brings more sap into the woodpecker’s mouth.
Because sap is so essential to a tree, wounds are quickly healed over to prevent loss of sap. Scientists still have not figured out how sapsuckers overcome a tree’s defenses and maintain a continuous flow of sap. One theory is that sapsucker saliva may contain a substance that acts as an anticoagulant, preventing sap from clogging up and sealing over the holes the bird creates.
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The chipping of hungry Hairy Woodpecker nestlings can easily be detected by human ears, even though it comes from deep within a tree cavity. One is reminded of how beneficial this species is when observing the steady delivery of food by these woodpeckers to their young. More than 75% of an adult Hairy Woodpecker’s diet consists of injurious insects, while the amount of useful insects and cultivated fruits that they destroy is insignificant. Beetle larvae (mostly wood-boring) make up 30% of the insects that are consumed, with ants ranking second, at 17%. Caterpillars, such as those pictured, comprise about 10% of an adult Hairy Woodpecker’s diet, but given this parent’s beakful, one wonders if the percentage is greater for nestlings.
A pileated woodpecker’s diet often shifts with the seasons. One study found that the primary food of these woodpeckers was fruit in fall, carpenter ants in winter, wood-boring beetle larvae in early spring, and a variety of insects in summer. During the winter, with the help of its impressive beak, the woodpecker pries off long slivers of wood from trees containing carpenter ants and exposes the ant galleries. It then uses its long, pointed, barbed tongue and its sticky saliva to catch and extract ants from the ant tunnels inside the tree. This winter diet can be confirmed by examining the contents of a pileated woodpecker’s droppings. Finding these droppings is simply a matter of locating a tree that has a considerable pile of wood chips at the base, indicating that a pileated woodpecker has spent a lot of time working on the tree – long enough to have deposited droppings in and amongst the chips. The droppings crumble easily and reveal a multitude of tiny, black, shiny carpenter ant body parts. (The whitewashed end is due to uric acid.)
Non-vocal communication between birds of the same species has become apparent in the last week or so — downy woodpeckers have started to hammer out bursts of steady staccato drum beats on nearby trees. Both male and female woodpeckers drum year round, but they do so most intensively from January to May, especially during the courtship and early nesting season which begin in March. Woodpeckers drum for a variety of reasons: defending territory, attracting a mate, maintaining contact with a mate, signaling readiness for copulation and summoning a mate from a distance. Woodpecker pairs do engage in duet drumming , which is thought to play a role in nest site selection and in promoting and maintaining the bond between mates.
The welcome sound of the “Morse Code woodpecker” is once again reverberating through our woodlands. Although many woodpeckers drum against hard surfaces with their bills, yellow-bellied sapsucker drums are distinctive — they usually begin with several rapidly repeated strikes in an “introductory roll” followed by a pause, then more strikes in an irregular pattern which some people liken to the Morse Code. These birds, like most woodpeckers, communicate with each other by drumming on different surfaces – often dead snags, but also metal signs and roof tops. They communicate over long distances, so the louder the drum, the better. Males are arriving back on their breeding grounds and establishing territories with the help of this drumming before the females arrive. Females arrive back about a week later than males, at which point, drumming will assist male sapsuckers in obtaining a mate. Females also drum, but less frequently, more softly and for shorter periods of time. Photo is of an adult female yellow-bellied sapsucker.
When I think of red-bellied woodpeckers, I think of the south, where their “churr-churr” call is relatively constant, and has been for many years. Over the past 100 years, like the cardinal, titmouse and mockingbird, this woodpecker has extended its breeding range northward. By the mid-90’s red-bellied woodpeckers had reached northern New England; 2001 marked the …first recorded breeding of red-bellied woodpeckers in Vermont (Brattleboro). While the origin of their common name appears fairly elusive, they do, in fact, have a blush of red on their bellies, if inspected at very close range. The red-bellied woodpecker is often mistaken for the red-headed woodpecker, for obvious reasons – they both have red heads. However, the back of the red-headed woodpecker is mostly black (red-bellied backs are black and white barred), and there is a large white patch on each wing of the red-headed. You must look closely at the red feathers of red-bellied woodpeckers to distinguish males from females. The male’s red feathers extend from the back of its neck (nape), cap and forehead down to the base of its bill. The female has red feathers on her nape and at the base of her bill, but not on her cap or forehead. Even though they’ve been around for the past decade, it is still a thrill to see this handsome bird. (Photograph is of a female red-bellied woodpecker sighted in Hartland, Vermont yesterday.)