The yellow-bellied sapsucker is a species of woodpecker. In terms of appearance, the bird is mottled black and white on its body, while the top of the head and neck have noticeable red patches—the underside can have a yellowish shade. They have a wingspan of approximately 14 inches (35 cm) with a body length of 8 inches (20 cm) and a weight of about 1.7 ounces (48 grams). The birds spend the winter in southern areas of the United States and even further south in places like Mexico. In the spring, they migrate north, and many of them go all the way into Canada.
These birds eat sap along with insects, and the insects actually provide more overall nutrition. They obtain the sap by hammering into trees with their beaks and creating holes. Yellow-bellied sapsuckers will frequently return to old holes to get more sap and keep them flowing. Sometimes insects will get caught in the sap, and the birds will eat them, obtaining valuable protein. In a way, the sap holes almost function like insect traps as much as anything else, and this is a common tactic among animals that burrow into trees for sap.
The yellow-bellied sapsucker tends to target weak and old trees, which some experts believe may be more nutritious. Some scientists think the yellow-bellied sapsucker has some kind of anticoagulant in its saliva that keeps sap flowing smoothly from wounded trees. It is very difficult to make sap flow constantly under normal circumstances, but the birds seem to have very little trouble.
Particular pairs of males and females are thought to breed for life, at least most of the time, and breeding generally happens in early spring. The male yellow-bellied sapsucker will dig out a hollow place in a tree for a nest, and the floor of the nest is generally lined with soft wood chips. A typical clutch in a normal breeding season will be about five eggs. They incubate for about 22 days, and the male and female both help with the process.
Once the young birds are born, the male bird does more work in keeping them alive and feeding them than the female. The chicks are mainly fed insects, and this is fairly common among birds, because the young often need more protein to grow. After about 28 days, the young birds are able to fly on their own, and they will generally leave the nest. The lifespan of the yellow-bellied sapsucker is approximately six to eight years.