On April 24th this year, NBC’s Today show featured a report from Rockport, Massachusetts. The story related a rash of damaged vehicles with over 20 owners reporting smashed side mirrors, and possibly one windshield. It takes a lot of power to break modern auto glass with its vinyl reinforcing. Was this a terrorist incident or a random gang attack in a disputed neighborhood?

The culprit was a woodpecker, specifically a Pileated Woodpecker, a prehistoric-looking bird up to 20 inches long and carrying a thick, heavy bill. Neighbors reported that at least one such bird has been causing problems for more than two years, knocking holes in valued landscaping trees and houses, but the car attacks took things to another level. People resorted to folding in their mirrors each night or covering the mirrors with plastic bags.

What caused the woodpecker to attack the cars? The same springtime hormone surge that causes American Robins and Red-winged Blackbirds to take out their anxieties on cars, sliding glass doors and plate glass windows. During breeding season male birds become confused when they see their own reflections, and so resort to pecking at the glass to fight off imagined intruders to their breeding territory. In the last two years I endured an American Cardinal banging on a cabin window at dawn each day, then watched a Wild Turkey banging on my chrome truck bumper and a tiny Chipping Sparrow slugging it out with my windshield. Fortunately, no smashed windows to report, but the birds often leave a mess when they depart for the next battle.

There are 241 species of woodpecker worldwide according to the International Ornithological Committee, with 23 of those breeding in the USA. The Pileated Woodpecker may now be the largest in the world since the larger Imperial and Ivory-billed Woodpeckers are likely now extinct. At the other end of the scale is the smallest of seven woodpecker species confirmed in Maine, the Downy Woodpecker.

This is a common bird, widespread across most of the US and Canada except in desert regions. They can be found in a range of wooded habitats either deciduous or mixed forest. The birds are comfortable living near humans, taking advantage of our created habitats like orchards, parks or larger backyards. Downy Woodpeckers are regular visitors to our suet and peanut feeders not only in winter but also during nesting season, enjoying the high energy food we provide. Other foods include insects, spiders, fruits, and sap from holes made by Yellow-bellied Sapsuckers or maple syrup producers.

Just seven inches long and weighing around one ounce, this handsome little bird is often confused with the larger Hairy Woodpecker. The Hairy has a much larger bill in comparison with its head than the Downy but their coloring can be quite similar. The feathers on the Downy appear soft and smooth while the Hairy can appear rumpled as if it just got out of bed. The striking black and white colors predominate but juvenile males display a red cap while adult males have a red patch on the back of the head.

It was long assumed that the Downy and Hairy Woodpeckers were closely related but DNA testing revealed that they are genetically distinct. Scientists struggle to explain why the birds are so similar in appearance and habits, using the term convergent evolution to explain how they have developed over millions of years. The birds can coexist in overlapping habitats because they favor different size plants for foraging, foods and nesting locations.

As with other woodpeckers, the Downy is a cavity nester, making use of holes they create, mostly in dead wood but they have been observed working on living wood if insects are present. While the Downy is not as powerful as the larger woodpeckers, it can still make a considerable hole with a couple weeks of work. Soft heart wood is easier to excavate while harder outer layers offer some protection for the nest and young birds. While making these holes, the bird can be identified by sound since it drums at a slightly slower rate than the Hairy.

The breeding season runs from the spring months into mid-summer. Once the cavity is satisfactory to the female, she lays between three and eight eggs. Mates are both involved in incubation of the eggs and caring for their young. Incubation requires around 12 days and the young birds appear fully grown in just over two weeks. The birds are generally found in their home territories around the calendar, year after year, with only a few birds observed migrating small distances.

Scientists have long recognized that woodpeckers play a vital role in the animal kingdom by providing home sites for a wide range of creatures. Kevin McGowan, an instructor at the Cornell Lab of Ornithology, notes that woodpeckers have great value in an ecosystem thanks to their ability to make “good holes.” McGowan lists the advantage of tree cavities: distance above the ground, protection from bad weather, and the ease of defending against intruders.

A 2017 study reported in the journal Diversity and Distributions that roughly 20 percent of birds species worldwide rely on tree cavities for roosting or nesting. Later studies showed that 30 percent of forest nesting birds in North America use tree cavities at some point in their lives and 90 percent or more of those cavities are made by the various woodpecker species. Black-capped Chickadees and White-breasted Nuthatches are considered weaker excavators but they are capable of enlarging holes in soft or rotting wood that have been started by the woodpeckers.

Cavity nesting birds range from tiny Northern House Wrens and Eastern Bluebirds to Wood Ducks, Screech Owls and Common Mergansers. Beyond the advantages of cavities for birds, a number of other species have been identified as using cavities at least part of the time. This list includes gray, red and flying squirrels, martens and fishers, and some species of snakes.

As described in my earlier article on the Pileated Woodpecker, woodpeckers have multiple adaptations that allow them to create holes that other birds are unable to make. First, they have two forward facing toes, and two toes that face backward, allowing the birds a strong grip on tree bark while banging away. Stiff tail feathers give the birds leverage as they lean back for a good whack. The strong bill has a bit of softer, shock-absorbing tissue at its base to prevent all the vibrations of each strike from jarring the brain. Finally, the strong neck muscles help absorb shock as do special structures and soft tissues protecting the brain inside the cranium.

The good news is that the Downy Woodpecker population seems to be in good shape for now, partly because in places like Maine forest cover is slowly increasing. Conservation efforts to develop forest sanctuaries and old-growth stands will also benefit the woodpeckers. Breeding bird surveys have estimated that the North American population of Downy Woodpeckers is approximately 13 million, making them the most frequently encountered woodpeckers.

Using the Merlin app on your phone or listening to YouTube videos you can learn the distinctive sound of a Downy Woodpecker hammering away on a tree. The next time you hear the sound, or when you see the bird at your suet feeder, give a quiet nod of thanks to the handsome little creature that is one of Nature’s most successful public housing developers!

If you like Ed Robinson’s writing, check out his two Nature Notes books! Click here for more information.