Woodpeckers are a diverse family of birds known for their specialized foraging methods. Their diet is highly adaptable, reflecting what is seasonally available in their environment and varying significantly between species. While the name suggests a singular focus, their consumption includes a complex mix of animal proteins, high-energy tree fluids, and diverse plant matter. This flexibility allows them to thrive across many different ecosystems, from dense forests to desert woodlands.
Invertebrates: The Core Diet
The primary components of a woodpecker’s diet are invertebrates, particularly the larvae of wood-boring insects. These high-protein grubs are often found deep within the decaying wood of dead or diseased trees. Woodpeckers locate these hidden meals by listening for the subtle sounds of the larvae moving inside the wood, a process known as auditory cueing. They then use their powerful, chisel-like bills to excavate the wood, creating deep, often rectangular, holes to access the tunnels of their prey.
Once the tunnel is exposed, the bird uses its remarkably specialized tongue to extract the insect. The tongue is long, sometimes extending twice the length of the bill, and is supported by a unique hyoid apparatus that wraps around the skull. The tongue’s tip is typically barbed or covered in sticky saliva, which allows the bird to hook onto or adhere to the soft-bodied larvae and pull them out. Species like the Pileated Woodpecker rely heavily on carpenter ants and large beetle larvae, which constitute a majority of their warm-weather diet.
Ants are another significant invertebrate food source, especially for ground-foraging species like the Northern Flicker. These birds often probe into ant colonies or rotten logs, using their sticky, elongated tongues to quickly lap up dozens of ants at a time. This insect-heavy diet is especially important during the breeding season, as the abundance of protein is necessary for the rapid development of their nestlings. The removal of these wood-boring pests also serves an ecological function by helping to control insect populations that can be harmful to trees.
Tree Fluids: The Sapsucker Specialization
A distinct group of woodpeckers, the sapsuckers, possess a highly specialized diet centered on consuming tree fluids and the inner layers of a tree. They methodically drill small, shallow holes, known as sap wells, into the bark of healthy, living trees to harvest the sugary liquid. This behavior is markedly different from the deep excavation used by other woodpeckers seeking wood-boring larvae. They often target trees with high sugar content, such as birch, maple, and fruit trees.
Sapsuckers create two primary types of wells depending on the season and the tree’s internal structure. In early spring, they drill deeper, round holes to tap the xylem sap, which provides much-needed energy when other food sources are scarce. During the warmer months, they switch to creating shallower, rectangular wells that access the phloem, a tissue containing sap with a much higher sugar concentration. They continually maintain these phloem wells to ensure a steady flow of the sweet liquid.
The sapsucker’s tongue is adapted for this liquid diet, featuring a brush-like tip that allows them to lap up the sap rather than spear it. The consumption of sap is often supplemented by eating the cambium and phloem tissues dislodged during the drilling process. Importantly, the sweet sap acts as a natural insect trap, attracting small flies, wasps, and ants that become a secondary protein source for the sapsucker when they return to tend their wells.
Plant Matter: Nuts, Seeds, and Fruits
Plant-based foods are a substantial and often seasonally necessary part of the woodpecker’s diet, providing carbohydrates and fats, especially when insects are less abundant. Nuts, particularly acorns, are a primary resource for several species, most famously the Acorn Woodpecker. This species engages in a unique caching behavior, drilling thousands of individual holes into a dead tree, utility pole, or snag to create a communal storage site called a granary.
The woodpeckers must select a hole that perfectly matches the size of each acorn, often moving the nuts to smaller holes as they dry out and shrink to maintain a snug fit. This intensive labor ensures a reliable food source, sometimes containing up to 50,000 acorns, which is defended communally by the family group. Other nuts, such as pinyon pine nuts, beechnuts, and pecans, are also consumed and cached by various species, typically stored in natural bark crevices.
Seeds from various sources also contribute to the diet, with black oil sunflower seeds and pine seeds being common selections. To access the kernel, woodpeckers often wedge a seed into a bark crevice or crack and then hammer it open. Finally, wild fruits and berries provide moisture and energy, particularly during late summer and autumn. Species consume a wide variety of soft fruits, including chokecherries, hawthorn, juniper berries, and wild grapes, which help sustain them into the colder months when insects are harder to find.