If you live in North America, Central America or Canada you might have noticed trees with intricate holes scattered on their trunks. It is likely that these holes were created by sapsuckers. To gain access to the energy dense sugary sap in trees, the sapsuckers will drill several shallow, small holes in a horizontal line, known as sap wells. They will lick at the sap with their hairy tongues that are shorter than those of other woodpecker species.
Sapsuckers do not appear to be so fussy about the trees that they drill wells in, Yellow-bellied sapsuckers use over 250 different tree species. However both sapsuckers mostly feed on aspen, birch, willow and pine trees. They also enjoy munching on insects and occasionally visit bird feeders especially when suet is on the menu.
Sapsuckers take on an important role in their community and are considered keystone species since they support many other species. The holes that they excavate in trees for nesting and the small sap wells they create provide other species with shelter and access to energy rich food. Other bird species, such as hummingbirds and cedar waxwings, as well as insects and bats, have been spotted taking advantage of the sap wells left behind by sapsuckers to fill up on some sugar treats.
Like other woodpeckers, these two sapsuckers also communicate through drumming on trees with their bills. The beginning of their drumming starts off fast with a very irregular sequence, similar to a rhythm created if you knocked over a bag of rubber balls onto the ground, while ending slow with longer pauses between the beats.
Drumming is understood to be used as a territorial display and often in aggressive contexts but the verdict is out as to whether it functions in other social contexts such as maintaining relationships and identifying individuals.
Yellow-bellied sapsuckers are found mostly on the eastern parts of North America whereas Red-naped sapsuckers can be found on the western parts of North America. They can overlap in the breeding grounds in British Columbia and south west of North America such as in Arizona, California, Texas, Colorado and New Mexico.
If you live around British Columbia you may find sapsuckers that have characteristics of both species such as a more red face. This is because there are three sapsucker species that breed in that region, the third being the red-breasted sapsucker. Although rare, all three species can breed with one another resulting in birds that have ancestry of two or all species, known as hybrids.
Sapsucker migrate, a rare behaviour to see in woodpeckers. In the summer they breed in Canada and Northern parts of North America and move South for the winter. Yellow-bellied sapsuckers migrate the furthest and over-winter south of Missouri to central America and the Caribbean. If you see a Yellow-bellied sapsucker during the winter months in Mexico, odds are that it will be a female. This is because females migrate further south than males.
Telling them apart
It is difficult to tell the two species apart. Even experts until fairly recently considered them as the same species. Do not feel disheartened when the ‘yellow’ in Yellow-bellied sapsuckers does not help you much when trying to tell them apart. They do have a yellow tint to their bellies but sometimes it is not so obvious.
The most obvious features to focus on are the throat and back of their head, the nape. In males the Red-naped sapsucker, as its name implies, has a red patch on its nape whereas the Yellow-bellied sapsucker does not. The red throat patch of the Yellow-bellied sapsucker is bordered by black whereas the black bordering the red throat patch is broken up in the Red-naped sapsucker.
The female of both sapsucker species can easily be told apart since the female Yellow-bellied sapsucker has a red forehead and no red colouration on the throat. The female Red-naped sapsucker has some red on the throat. Female red-naped sapsuckers can often be mistaken for the male Yellow-bellied sapsucker as they have a red throat and sometimes lack a red patch on the back of their head. However, the red throat patch is smaller than their male counterparts and they have a white chin.
In both males and females the mottled white markings on their backs can help with distinguishing them. The Red-naped sapsucker has more organised white markings on its back that create two distinct lines whereas the white markings are more messy in the Yellow-bellied sapsucker.