Picidae (PISS-a-dee)
Woodpeckers are uniquely adapted for a life lived vertically. While most birds forage on horizontal branches or the ground, woodpeckers have evolved a specialized “toolkit” that allows them to thrive on the sheer sides of tree trunks. By using their bodies as high-precision tools, they can access food sources—like deep-seated larvae and sugary sap—that are out of reach for many other birds.
The Vertical Tripod: Feet & Tails
To work on a vertical surface, a woodpecker needs incredible stability. They achieve this through a special toe arrangement and a “tripod” stance. While many birds have three toes pointed forward and one pointed backward, woodpeckers have two pointing forward and two pointing back (an “X” shape called zygodactyl) allowing them to better grip trees.
To provide additional stability, woodpecker tail feathers have extra-stiff shafts. When a woodpecker perches, it presses its tail against the tree to act as a kickstand or third leg. This supports their weight and leaves their head free to hammer.
A Foraging Strategy Built on Physics
Woodpeckers are the only birds that use their heads as hammers to excavate food. While it was long thought that spongy skulls protected woodpeckers from impact, their anatomy actually works more like a solid hammer than a shock absorber. If their heads were soft or flexible, they would lose the very force needed to crack into wood—much like trying to drive a nail with a rubber mallet. Instead, their remarkably rigid beaks and skulls ensure that 100% of the striking power is transferred directly into the tree, making them incredibly efficient natural drillers (Van Wassenbergh 2022).
Woodpeckers avoid brain injury primarily due to their scale. Because a woodpecker’s brain is so small, it has a much higher surface-area-to-mass ratio than a human brain, allowing it to withstand deceleration forces that would be fatal to us. Their brain fits tightly within the skull with a very thin layer of cerebrospinal fluid, leaving no “slosh room” for the brain to collide with the skull wall. Furthermore, the brain is oriented so that the impact force is distributed across a broad area, rather than being concentrated in one spot (Van Wassenbergh 2022).
The Tongue: A Specialized Probe
Once a woodpecker drills a hole, it needs a way to extract its meal. The tongue is their most specialized tool, sometimes reaching up to a third of the bird’s total body length! In species with exceptionally long tongues, it’s too big to fit in the mouth. Instead, the base of the tongue (the hyoid bone) wraps around the back of the skull. In some cases, it loops all the way over the top of the head and anchors near the nostrils. You can see a demonstration of this remarkable anatomy in action here.
Because woodpeckers can’t see into the deep crevices where they forage, their tongues act as a primary sensory tool. Rather than a “one-size-fits-all” design, woodpecker tongues have a specialized combination of traits depending on the bird’s preferred diet. Insect-eaters often have barbed tips for spearing larvae or hair-like structures coated in sticky mucus secreted by large salivary glands to “glue” ants and beetles. Sapsuckers often have shorter tongues equipped with fine, hair-like structures designed to gather liquid sap from the trees.
Beyond their surface textures, woodpeckers also have two intrinsic muscles that allow them to move the very tip of their tongue in all directions—giving them the dexterity needed to navigate winding tunnels and extract hidden insects.
The “Rollercoaster” Flight
Woodpeckers even move through the air differently. Most woodpecker species use undulating flight, flapping to gain height and then tucking their wings tight to glide in a downward dip. This “flap-and-tuck” rhythm is an energy-efficient way to travel from one vertical workstation to the next.
Communication: The Woodland Drummer
Most songbirds attract mates and defend their territory with songs. Woodpeckers take a different approach: they use percussion. To signal their presence, a woodpecker will find a resonant object—a hollow log, a dead branch, or even a metal chimney pipe—and strike it in a rapid-fire burst. This is known as drumming.
Unlike pecking for food (which is slower), drumming is a loud, rhythmic “broadcast” intended to carry through the woods. Each species has its own unique “signature” beat. Whether they are defending a territory or looking for a mate, both sexes use their beaks to “broadcast” their message. While woodpeckers do have vocalizations, drumming is their primary way to claim a territory and find mates.
The Forest Builders: Primary Cavity Nesters
Perhaps the most important role woodpeckers play at Edgewood is that of the primary cavity nester. While a few other birds are “weak excavators” that can peck into soft, rotting stumps, woodpeckers are the forest’s heavy-duty architects—the only birds uniquely built to drill deep, lasting homes into solid wood.
Because many woodpecker species prefer to drill a fresh nesting site each year, they leave behind a legacy of “second-hand” real estate. These abandoned cavities become essential safe harbors for secondary cavity nesters—birds that require a hollow to survive but lack the tools to build one.
At Edgewood, neighbors like Western bluebirds (Sialia mexicana), chestnut-backed chickadees (Poecile rufescens), and white-breasted nuthatches (Sitta carolinensis) rely on these recycled woodpecker cavities. Without the constant construction work of the woodpecker family, these iconic birds would have fewer places to sleep or raise their young.
Fun Facts
- Research suggests that approximately 18% of bird species worldwide are secondary cavity nesters—birds that require a tree hole for survival but cannot drill one themselves. In many habitats, these birds, along with small mammals, reptiles, and insects, rely almost entirely on the holes left behind by woodpeckers. By creating these essential safe harbors, woodpeckers act as the primary architects for nearly one-fifth of the avian world.
- Woodpeckers are aptly named pájaros carpinteros (carpenter birds) in Spanish, honoring their role as the natural woodworkers of the forest.
Learn More
Avian Report. Woodpecker feet and toes: A gripping and climbing machine.
Brandogirl. Pileated Woodpecker vs Metal Pole [Video]. YouTube.
Cornell Lab of Ornithology. 2024, Mar. 18. Woodpecker diversity [Video]. Bird Academy. YouTube.
Cornell Lab of Ornithology. 2024, Mar. 23. Why is that woodpecker pecking on metal? [Video]. Bird Academy. YouTube.
Cornell Lab of Ornithology. 2024, Mar. 27. Why don’t woodpeckers fall while pecking? [Video]. Bird Academy. YouTube.
Cornell Lab of Ornithology. 2025, Apr. 3. How to recognize woodpeckers by their drumming sounds [Video]. All About Birds.
Cornell Lab of Ornithology. 2026, Jan. 8. Two ways to climb a tree: Backyard birds revealed [Video]. All About Birds.
EverythingAnimal. 2021, Apr. 10. Downy Woodpecker Drumming [Video]. YouTube.
HAWI Studios. 2023, Oct. 26. WoodPecker Pecking on Hardwood and Eating Termites [Video]. YouTube.
WitmerLab. 2019, Apr. 3. Random act of anatomy – Woodpecker hyolingual (tongue) apparatus [Video]. Ohio University. YouTube.
References
Bleak, J.F. 2017, Jan 28. Dendrocopos major skull [Illustration].
Bock, W. 1999, Mar. Functional and evolutionary morphology of woodpecker. Ostrich – Journal of African Ornithology 70(1): 23-31.
Devokaitis, M. 2025, Mar. 24. The hole story: How woodpeckers make homes for the rest of the forest. Living Bird.
Genduso, G.A. 2026, Feb. 11. Woodpecker flight pattern [Illustration].
Gosse, P.H. 1849. Foot of parrot and of woodpecker [Illustration of woodpecker foot, adapted]. Natural History, Birds 2:177. S. & J. Bentley, Wilson, and Fley, Bangor House, Shoe Lane, London.
Johnston, N.E. 2014, Jun. The Avian Tongue. Golden Gate Bird Alliance.
Lovette, I.J., and J.W. Fitzpatrick (Eds.). 2016. Handbook of Bird Biology (3rd ed.). Wiley-Blackwell, Hoboken, New Jersey.
van der Hoek, Y., G.V. Gaona, and K. Martin. 2017, Aug. 6. The diversity, distribution and conservation status of the tree-cavity-nesting birds of the world. Biodiversity Research 23(10).
Van Wassenbergh, S., et al. 2022, Jul. 25. Woodpeckers minimize cranial absorption of shocks. Current Biology 32(14).
Browse Some Edgewood Plants in this Family
