Common sapsucker
The Yellow-bellied sapsucker (Sphyrapicus varius ) is a medium-sized woodpecker that breeds in North America. Well-known for their feeding habits, these birds can injure trees and attract insects and are sometimes considered a pest.
The forehead of the Yellow-bellied sapsucker is coloured bright red in the male (and very occasionally yellow), and a lighter shade of red in the female. Sometimes, this is the only place on the head a female will have red colouration, if it has any at all, as the female rarely has a black head with a few buff spots. The crown is bordered black, is usually red, and is sometimes mixed with black in the female. There is a white stripe, starting above the eye, that extends and widens to the nape, being broken up by a thin black line on the hindneck. There is a broad black stripe going through the ear-coverts and down to the side of the neck. Below this black stripe is a white stripe that goes from the nasal tufts to the side of the breast. The throat and chin can be used to differentiate between the sexes, as they are white in the female, and red in the male. The mantle of this sapsucker is white, and there are irregular black bars that extend from it to the rump. The lower rump is white, and the uppertail-coverts are white with some black webbing. The wing coverts are black, and there is a white panel on the medians and central greater-wing coverts. The flight feathers are black with white tips. The innermost tertials are white and black. The underwing is barred greyish and white. The uppertail is black, with some white webbing and white tips sometimes being present on the outer feathers. The underparts, excluding the pale breast and above, are tinged yellow, transitioning to a whiter colour in the lower region of them. The side of the breast down to the undertail coverts have black arrowhead-shaped markings. The chisel-tipped bill is relatively short and straight, with a slate to blackish colour. The legs are blue-grey to green-grey in colour, and the irides are a deep brown. The juvenile is a dark olive-brown colour overall, with a buff-striped head and a streaked crown. The throat is usually white, although, in the male, there may be some red. The upperparts are generally a mottled pale and blackish colour. The breast is scaly, and the central part of the belly is a very pale yellow colour. The tail is barred more than in the adult.
Yellow-bellied sapsuckers breed in Canada, eastern Alaska, and the northeastern United States. They winter in the eastern United States, West Indies, and Central America. These birds are generally found in deciduous and mixed coniferous forests and may also be found in open woodlands, and semi-open habitats. They are also seen in larger trees in pastures, clearings, suburban areas, and occasionally in palm groves.
Yellow-bellied sapsuckers are active during the day and spend most of their time near their sap holes or foraging. These birds usually forage by themselves; however, they sometimes join small groups in the winter and occasionally mix into flocks of insect-eating birds in the winter. Insects are usually caught by perching on a tree branch or on the ground. Before feeding consistently on a tree, Yellow-bellied sapsuckers lay down exploratory bands near a live branch. These bands are laid down in horizontal rows. When the bird finds a proper tree it lays down more holes to feed, about 0.5 centimeters (0.20 in) above the primary bands. These form columns. Each hole is then drilled further, with the sapsucker enlarging it vertically, making it yield more sap, but only for a few days. The top holes in each column thus provide phloem sap, and this sapsucker also utilizes the best from the edges of the holes drilled. In the winter, when the holes are drilled on conifers, bast is likely the birds' most important food. Yellow-bellied sapsuckers use various calls to communicate with each other. Males usually produce a long-distance nasal 'neaaah,' 'owee-owee,' 'wee-wee-wee-wee,' or 'kwee-urk' at the start of breeding to attract the mate to various places within their territory. When birds of a family group meet, they exchange low 'week week', 'wurp wurp', or similar low calls. A scratchy 'quirk quirk' is given when pairs meet at the breeding territory. When sapsuckers are alarmed, they will utter a soft mew call, getting louder and hoarser as the threat increases and during a conflict, they produce a shrill 'quarr'.
Yellow-bellied sapsuckers are generally carnivores (insectivores). They feed mainly on insects but also consume fruits, tree sap, and nuts. They also take bast from trees and occasionally berries and buds.
Yellow-bellied sapsuckers are monogamous and form pairs. The male usually arrives on the nesting grounds about one week before the female early in the Northern Hemisphere spring, often before heavy snowfall has stopped. The actual breeding season occurs from April to July. Yellow-bellied sapsuckers nest in pairs in a large cavity excavated in a live deciduous tree and both sexes work to make the nest. During nest excavation, the male may perform a courtship flight. This flight consists of the bird rapidly flapping its wings below its partner. It seems to build the pair bond and help increase attachment to the nest. Members of a pair also perform a dance where they bob their heads and repeatedly open their wings halfway. They also have the courtship ritual of touching their bills together. Courtship additionally consists of giving 'quirk' notes and, from a distance, 'kwee-urk' calls. The female lays a clutch of 4 to 7 white and spotless eggs and both parents incubate them during the 10 to 13 days. When the chicks hatch, they are blind, naked, and helpless. They are brooded for 8 to 10 days by both parents and after 25 to 29 days, the young leave the nest for the first time. They become independent after about 2 weeks and start to breed when they are 1 year old.
Yellow-bellied sapsuckers are common in their range. They are not considered globally threatened and do not face any major threats at present. Despite that populations of these birds are decreasing probably due to the loss of suitable nesting and feeding habitat.
According to Partners in Flight resource, the total population size of the Yellow-bellied sapsucker is around 14,000,000 breeding individuals. Currently, this species is classified as Least Concern (LC) on the IUCN Red List but its numbers today are decreasing.
Because the feeding habits of the Yellow-bellied sapsucker can injure trees and attract insects, it is sometimes considered a pest. The birds can cause serious damage to trees, and intensive feeding has been documented as a source of tree mortality. Sapsucker feeding can kill a tree by girdling, which occurs when a ring of bark around the trunk is severely injured. Certain tree species are particularly susceptible to dying after being damaged by Yellow-bellied sapsuckers.
