Our Woods and Our Woodpeckers
- jhansen49
- Apr 7
- 6 min read
The family of woodpeckers, Picidae, includes seven species that rely on the woods of southern New Jersey. Many of these birds can also be seen at backyard bird feeders. Another 16 species live in the western U.S. and another 37 species reside in the boreal and montane habitats of Canada or habitats in Mexico. Globally there are somewhere from 234 to 254 species. Interestingly, woodpeckers are found throughout the world except in Australia, New Guinea, and New Zealand. It’s not clear why they never dispersed to those areas.
Most woodpeckers, and all those in the eastern U.S., depend on forest trees. They are well adapted to this life. The tail feathers are stiff and pointed to form additional support that enables them to perch upright on the tree trunk and brace themselves for hammering into the wood. They have two toes facing forward and two facing backwards for better clinging. Perching birds, in contrast, have one backward facing and three forward toes for gripping branches.
All woodpeckers excavate holes in trees for nesting. They have incredibly hard, chisel-like bills that enable them to drill and hammer at levels 300 times the impact that would give a human a concussion. They do have numerous specialized structural features that allow this, among which is a skull that is reinforced to withstand repeated blows and a brain that is oriented in the skull so there’s a large surface area to absorb shocks. The lower part of their bill, the mandible, tends to strike wood first which allows the force of the shock to be distributed throughout the body, rather than just in the skull.
They also have a super long tongue which wraps around their skull when it’s retracted. This provides another protection when hammering because it acts somewhat like bubble wrap to protect the brain. Male bighorn sheep have a similar adaptation to avoid concussions.
In woodpeckers the tongue can be three times as long as the bill. Woodpeckers extract insects from tree bark and within dead tree trunks using this tongue. They also listen. Insects, like wood boring beetles and their larvae, make sounds that the woodpecker can hear.
Woodpeckers feed on beetles, ants, grasshoppers, caterpillars, and other miscellaneous invertebrates including small lizards. About half their diet consists of plants, however. They eat berries, nuts, fruits, and sap. In fact, the sapsuckers (genus Sphyrapicus) are specialized for this. They drill shallow wells into living trees and lap up the sap that oozes out with their brushy tongues. They also eat insects that show up to drink the sap.
Woodpeckers lack the vocal abilities of perching birds so they can’t use songs to attract mates or fend off rivals, although they do have calls. Instead, they utilize drumming to communicate. Males and females both drum and this behavior is seasonal, often being limited to the breeding season. Most woodpecker species are monogamous and mate for life. Both male and female care for the young.
All woodpeckers nest in cavities. They excavate nest holes using their chisel-like bills, preferably in dead trees or those with wood-boring insects. They will also drill into healthy live trees, especially those with softer wood such as pines, birches, fruit trees, and sweetgums.
Nest cavities, which are usually drilled fresh each year, become important sites for other animals in the forest. A 2004 study of Northern Flickers in British Columbia found that the cavities they had created were later used by Bufflehead Ducks, American Kestrels, Northern Saw-whet Owls, Mountain Bluebirds. woodrats, mice, weasels, and squirrels, among others.
Out of approximately 240 woodpecker species across the planet, 39 are known to be threatened. The International Union for the Conservation of Nature lists 39 woodpecker species as either near-threatened, vulnerable, endangered, or critically endangered. This is due largely to the loss of forests throughout the world. For example, Southeast Asia has the highest biodiversity of woodpeckers but is also the area of the planet with the most human destruction of habitat.
Fortunately, most woodpeckers in the Eastern U.S. are still thriving and some, like the Pileated Woodpecker, have even increased in number as forests have been restored or regrown.
New Jersey Woodpeckers
Pileated Woodpecker (Dryocopus pileatus): This is the largest woodpecker in North America and is very dramatic in appearance with its bright red crest and black and white body. Males have a red stripe on their cheek. Pileated Woodpeckers drill distinctive rectangular-shaped holes in rotten wood to get at insects, especially carpenter ants, their favorite food. They are forest birds that require large, standing dead trees and downed wood. Forests can be evergreen, deciduous, or mixed and are often old, particularly in the West. In the East they live in young forests as well and may even be seen in partially wooded suburbs and backyards. If you are lucky, you may see a Pileated Woodpecker at the Oldmans Creek Preserve.
Downy Woodpecker (Dryobates pubescens): This is the smallest woodpecker in the U.S. and is readily seen at bird feeders. The Downy’s small size enables it to reach food sources that are inaccessible to larger species, even permitting feeding in weeds. The male has a red spot on the back of its head. In appearance, the Downy mimics the Hairy Woodpecker. Mimicry usually provides some type of defensive benefit to the species doing the mimicry, but it’s not clear what advantage this mimicry provides to the Downy. A recent study suggests that looking like the more aggressive Hairy may assist a Downy to chase off other competing species of birds from feeder resources.
Hairy Woodpecker (Dryobates villosus): The Hairy is a larger version of the Downy Woodpecker. Both come to bird feeders, but the Hairy does so less than the Downy. The Hairy woodpecker takes advantage of the work of other woodpecker species, sometimes coming behind pileated woodpeckers to inspect their excavations for additional insects. They also feed on sap left behind by sapsucker woodpeckers.
Northern Flicker (Colaptes auratus): This beautiful woodpecker with its spots and barring, bright yellow under its tail and wings, and white rump in flight is more frequently seen on lawns and open fields than at feeders. That’s because they feed primarily on ants in the ground, licking them up with their barbed tongues. The male has a black “moustache” stripe. This species has declined in number and the reasons for this are not well known. Pesticide use and competition with starlings may be factors, as well as the loss of woodlands, but these conditions affect other types of woodpeckers too.
Red-bellied Woodpecker (Melanerpes carolinus): This woodpecker has a bright red head, which causes viewers to confuse them with Red-headed Woodpeckers. There is a reddish coloration on the belly of this bird that can be seen easily but is not as bright as the head. Red-bellied Woodpeckers are only found in the Eastern U.S., unlike the species described above. They are also frequent bird feeder visitors and especially like suet (as do almost all woodpeckers).
Red-headed Woodpecker (Melanerpes erythrocephalus): This is another woodpecker found in the Eastern U.S. and not in the West. It is one that stores nuts in crevices of trees for later retrieval. It also eats fruit and will catch insects in midair like flycatchers. Unfortunately, there has been a 70% decline in their populations over the last 50 years. They are now listed as “Near Threatened” on the IUCN Red List, and have been placed on the ”State of the Birds Watch List.” They are a Threatened species on the New Jersey Threatened and Endangered Species list.
Yellow-bellied Sapsucker (Sphyrapicus varius): This Eastern U.S. woodpecker has a nice yellow wash on its underbelly although it has some bright red coloration on its head and throat that are much more visible. It will frequently visit feeders but not in the winter because nearly the entire population moves south from their northern U.S. and Canada breeding grounds. Many spend the winter in the southern U.S. or Mexico but some travel as far as Panama. This is the only migratory woodpecker in the U.S. where the whole population migrates. As the name indicates, sapsuckers drill numerous rows of small closely placed holes to feed on sap and the insects entrapped by the sap.
Sources:
American Bird Conservancy: https://abcbirds.org/blog20/woodpecker-species-united-states/
Cornell University: allaboutbirds.org/guide/Pileated_Woodpecker
Neil Durfee. “There’s a New Theory for Why Downy and Hairy Woodpeckers Look So alike.
https://www.audubon.org/news. February 26, 2018.
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