in the garden
Hoping for a Lively Spring? Welcome the Woodpeckers.
The males of the species prepare for mating season by excavating nests for the approval of the females — and even other birds and animals.
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Do you hear that? The avian orchestra is rehearsing in anticipation of another spring, with more notes sounded each day after winter’s relative silence.
In the percussion section, the male woodpeckers are starting to drum, “proving their vitality by making the loudest noise they can,” said Paul Bannick, a Seattle-based author and wildlife photographer whose latest book is “Woodpecker: A Year in the Life of North American Woodpeckers.”
The emphatic drumming, meant to attract mates and drive off rival males, is by no means the only way woodpeckers are at the pulse of things.
Lately we’ve learned about the importance of making room in our gardens for keystone plants, native species that are disproportionately important to local ecosystems. Oaks are perhaps the most famous example. Were they to disappear, entire ecosystems could collapse — like how an arch would topple if its keystone were removed.
But what about keystone animals, like woodpeckers? Shouldn’t we intentionally try to make them at home, too?
“Woodpeckers are the heartbeat of our forests,” said Mr. Bannick, whose work focuses on North America’s natural history, in particular bird conservation. In “Woodpecker,” he introduces us to the 41 North American species — ranging from the Arctic to the Caribbean. That includes 22 who make their home in the continental United States (11 of them within an hour of his Seattle garden) — all while also helping make homes for other species.
The Spanish name for woodpeckers, pájaros carpinteros or carpenter birds, honors their contribution: These are ecosystem engineers who apply their excavating skills to carve roosts for themselves and their offspring, many of which are subsequently repurposed as nests by birds as diverse as wood ducks, owls, bluebirds, tree swallows and more — and by other animals, including squirrels, martens, bats and raccoons.
“None of these would survive without woodpeckers,” he said, noting that many animals have evolved to capitalize on their work.
Part of the reason is the math: Male woodpeckers typically start work on several nests in anticipation of mating season, excavating each cavity pretty far along before showing the possibilities to the female, who takes her pick. Some of the extras represent those potential nests for other animals.
Plants (and therefore gardeners) are other beneficiaries, and Mr. Bannick calls woodpeckers “the cleanup crew” for their powerful organic pest-control efforts. They devour termites, carpenter ants, bark beetles, caterpillars, aphids, weevils and more.
With their impressive beaks and ingeniously designed long, sticky tongues, “woodpeckers are unique in being able to access and eliminate threats beneath the bark,” Mr. Bannick said, where insect eggs and larvae usually lurk, “so they eliminate the pest before they become a problem.”
All that excavating has another benefit: It accelerates the process of nutrient cycling, helping decompose and transition wood to organic matter that enhances the soil below.
“For gardens to come alive,” Mr. Bannick said, “that’s the best thing we can do: welcome the woodpecker.”
Strategic Tree Work, by Bird and Gardener
An internet search for “attract woodpeckers” suggests that the way to invite these charismatic, boldly colored birds is with a suet feeder, but Mr. Bannick thinks bigger. Though each species has particular dietary and site preferences, some general guidelines apply, and he has strived for almost 30 years in his garden to provide the resources and some habitat elements they require.
Noting that most species are nonmigratory, he stresses the importance of diverse plantings, which provide food for every season, and he makes sure to offer year-round access to water (in cold-winter zones, floating de-icers will keep the surface unfrozen).
Most critically, he practices strategic, often hands-off management of declining and dead trees.
Woodpeckers, though mostly insectivorous, also include some plant material in their diets.
In breeding season, fatty grubs, such as beetle or ant larvae, may headline the menu, but in summer many switch to fruit.
Native dogwoods (Cornus), sumac (Rhus), mountain ash (Sorbus), manzanita (Arctostaphylos), black cherry (Prunus serotina), elderberry (Sambucus canadensis), various wild grapes (Vitis), and hollies (Ilex), are just a few possibilities. Some woodpeckers also eat fruit we grow to eat ourselves, Mr. Bannick said, like apples, pears, blackberries, raspberries and blueberries.
As the season progresses, the birds will transition to eating more nuts and seeds including acorns, for which the clown-faced, highly social acorn woodpecker is named. Groups of them drill holes in dead trees to create granary trees — their own giant acorn pantries.
Nests in Trees, or Perhaps in Bird Boxes
Woodpeckers have an impressive physiology that allows them to withstand the strong impact of their own hammering. Various anatomical features combine to protect them, including a spongy, vibration-absorbing skull. They also have very little cerebrospinal fluid in their cranial cavity so their brains don’t slosh around. In some species, the long tongue wraps around the brain, which may give extra padding. Their ribs are reinforced, and their extra-strong, specialized feet and extra-stiff tail feathers anchor them while they work.
Woodpecker physiology has inspired safer motorcycle and football helmets and has even influenced medical research on Shaken Baby Syndrome.
Even with such built-in protection, woodpeckers are strategic about tree work and know a good tree when they see (and hear) one. They watch and listen for insect activity to identify trees that will yield maximum results with the least effort — whether they are aiming to fashion a cavity or simply extract a meal.
Seeing signs of excavation, gardeners may worry that the birds are harming healthy trees, but — with one exception — “every woodpecker in North America that nests in a tree, prefers to nest in a rotted tree,” said Mr. Bannick.
The exception is the red-cockaded woodpecker in the Southeast, which nests only in live trees, specifically pines, but even it typically selects trees with some softening.
Despite the decline underway in trees woodpeckers typically target, excavating is a serious commitment. It takes on average about two to four weeks for most species to create a roost. The red-cockaded’s efforts may span several years.
Too often, the gardener’s instinct with a dying or dead tree is to cut it down. Mr. Bannick takes quite the opposite approach, celebrating and even creating wildlife trees, or snags, from dead or dying trees.
“I think we need to change the concept of beauty,” he said. “We have to think about not only the retention of snags, but the recruitment of snags in some cases.”
He once intentionally topped an old hemlock that had died, and he has already identified which tree will evolve into the next snag.
Not every garden has an ample supply of such candidates, and though making room for a bluebird box is probably more familiar, some woodpecker species will be grateful for a properly sized nest box, too. Designs suiting the pileated woodpecker and Northern flicker can be accessed in All About Birdhouses from Cornell Lab of Ornithology’s NestWatch, and ready-made flicker and wood duck boxes can host larger woodpecker species. The Washington Department of Fish and Wildlife offers downy and hairy nest box plans.
Mr. Bannick has three boxes at his garden and a trick for gaining the birds’ buy-in: Ahead of woodpecker breeding season, he stuffs the cleaned boxes with wood chips.
The male “can show his vitality by pulling chips out of the box,” Mr. Bannick said, if not actually doing the heavy lifting of excavating.
The bird lets the chips fly, hoping the female notices and joins in. Together, they may start something bigger than just the two of them — something positively transformational.
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