One of the most welcome signs of early spring is the unmistakable sound of woodpecker drumming. Longer day length and surging hormones trigger the rapid hammering, which loudly asserts territorial and mating rights to other woodpeckers — ”This is MY territory!“
Unlike other songbirds, woodpeckers don’t have a distinctive song as part of their avian vocabulary. Instead, drumming is the way woodpeckers communicate to establish and maintain their breeding territories. Drumming is also used to attract a mate, solicit sex, guard mates, maintain contact, and strengthen pair bonds. And drumming is not just the domain of males; females drum too, and pairs often engage in drumming duets.
But drumming is as distinctive as any bird song. The ~23 woodpecker species of North America (north of Mexico) have an extraordinary repertoire of display drums, each unique in tempo, pitch, and frequency. Learning to identify woodpeckers “by ear” can be challenging, but with practice most drumming can be matched to species with a high level of confidence. And if a species can’t be deciphered by ear, the sound will help birders more easily locate a bird to identify it by sight.
Drumming vs. Tapping
Woodpeckers drum by rapidly pecking on a resonant object to create a pattern of sound. Both natural and artificial objects are selected to drum on, including hollow trees, stumps, logs, utility poles, chimneys, rain gutters, metal roofing, trash cans, and just about any other object that echoes loudly. It’s all about proclaiming a sound signal as far and as loud as possible.
Tapping occurs at a slower rate than drumming, and is usually associated with feeding or excavating a nest hole. Tapping allows woodpeckers to judge the soundness of wood for excavating a nest cavity or harboring a tasty meal of beetle larvae, carpenter ants, or tree sap.
Let’s listen to the drumming of a few woodpecker species and hear what makes each unique:
Red-headed Woodpecker
Red-headed Woodpecker’s drumming includes a staccato roll with 1-second bursts of 19–25 beats per second, repeated 2–3 times. They also tap slowly on surfaces near the nest cavity when choosing a nest or communicating with their mates.
White-headed Woodpecker
Compared to other similar-sized woodpeckers, the drumming of this western species is rather loose and slow, consisting of an even roll of 15–30 beats lasting fewer than 1 ½ seconds.
Norther Flicker
Male and female Northern Flickers have a loud, evenly spaced, rapid drum. Each burst lasts about a second, during which the bird strikes the tree around 25 times.
Yellow-bellied Sapsucker
Sapsucker drumming is slower and more irregular than other woodpeckers. Its stuttering cadence can sound like somebody tapping out Morse code. Most drumming is done by males during breeding season.
american Three-toed Woodpecker
The drumming of the American three-toed Woodpecker is powerful and rapid, fading towards the end. A burst is only 1–1.4 seconds long. In this video, a female is drumming.
PILEATED WOODPECKER
Pileated Woodpeckers drum powerfully on trees at any time of the year, typically a fairly slow, deep rolling that lasts about 3 seconds. Their display drum has 11–30 beats per burst.
Woodpecker Adaptations
Using your head like the business end of a jackhammer requires some very special adaptations. Consider that when a woodpecker whacks its head against wood ~20 times a second, at 1,200 times the force of gravity, it’s the equivalent of us humans hitting our head against a brick wall at 16 mph! How do woodpeckers manage this without suffering concussion, detached retinas, or other repetitive head injury? Well, they manage through many remarkable adaptations:
Enlarged Skull — Woodpeckers have a thicker skull than most other birds, which contains extremely strong yet spongy compressible bone. The skull and the beak are linked by elastic connective tissue, acting in concert like shock absorbers.
Brain — The woodpecker brain is tightly enclosed in the skull with very little cerebrospinal fluid, so has less room to move in the skull while tapping or drumming. In contrast, humans have more cerebrospinal fluid and more room for the brain to “slosh” around in the cranium. Brain slosh can occur from sports injuries, car/motorcycle accidents, or other recreational activities and may cause Traumatic Brain Injury (TBI). TBI affects the brain’s white matter and results in symptoms ranging from headaches to sleep disorders and cognitive impairment. Inspired by the woodpecker’s impact-withstanding physiology, physicians and students have developed new wearable neck braces to prevent neurological damage from concussions in young athletes.
Beak — The strong bones that make up the woodpecker’s bill are strengthened by a horn-covered beak (which can hammer into wood up to 12,000 times per day!). A “frontal overhang”—where the frontal bone bulges out over the bill—allows force to be dispersed downward, away from the brain casing vs. against it.
Tongue — The woodpecker tongue is an anatomical wonder. Depending on the species, its tongue is up to 4 inches long, and wraps around the skull when retracted, providing even more cranial stability. Within the long tongue is the ‘hyoid apparatus’ – a collection of small bones supported by muscles and cartilage that fold and unfold accordion-like, enabling the woodpecker to probe its tongue deep into wood to extract ants and grubs.
Eyes — Woodpeckers have a thick inner eyelid, also called the third eyelid or nictitating membrane, which protects their eyes when they’re hammering. The membrane acts like a seatbelt to keep the eyeballs in their sockets and prevent tearing of the retina. Woodpecker eyes also have two special organs called the pectin and the choroid. The instant before a woodpecker’s head hits a hard surface, these organs engorge with blood and other fluids to increase pressure inside the orbital sockets and prevent the eye from ‘sloshing’ forward.
Neck Muscles — Likewise, a split second before every tap, the dense muscles in the woodpecker’s neck contract and distribute the force of the impact away from the skull down through the rest of the body like shock absorbers.
Tail — All birds have a set of fused bones at the base of the backbone (the tail bone or pygostyle). In woodpeckers, the pygostyle is laterally expanded to provide more surface area for muscle attachment. This feature and stiff tail feathers allow the bird to prop itself against a vertical surface like a tripod.
Feet — Woodpecker feet are specialized for gripping fast to vertical tree trunks. Their feet are ‘zygodactyl’ – with two toes pointing forward and two backward (unlike many songbirds’ three-and-one) and each toe is equipped with a large claw.
Treat yourself today (goodness knows self-care is needed after this past week!) and take a moment to head outside and listen for the early spring salutation of woodpecker drumming. It’s one of the most recognizable and unique of bird sounds and the more you know about it, the more you will enjoy this unique “tick-a-tick-tick, tick-a-tick-tick” every time you hear it.
Which woodpecker species drum in your neck of the woods?
What is the strangest thing you’ve seen and/or heard a woodpecker drum on?
For years, I had a Northern Flicker drum on my metal DISH receiver — a jarring, clanging salvo that reverberated like the Liberty Bell while also fuzzing up my TV reception.
The floor is now open for your latest bird observations and other avian news!