The few beneficiaries of ash borer plague
- John Lorson: The Rail Trail Naturalist
- June 25, 2021
- 922
Checking in on the brood, this red-bellied woodpecker delivers a meal to its chicks inside a cavity excavated in a dead ash tree. An invasive pest, the emerald ash borer beetle has been responsible for the demise of at least 100 million ash trees in North America over the course of the past 20 years, and while the ash population has been devastated, a handful of native species including several woodpeckers have benefitted from the invasion — at least in the short term.
“John, there is a gigantic woodpecker rapping on the outside of my house!” It was my mother-in-law calling and she was fit to be tied.
True to the dynamic of our relationship I answered in my typical smart aleck manner.
“Well, why don’t you let him in?” I said. “He’s obviously a well-mannered bird, given that he’s gone to the trouble of knocking.”
“I’m serious.” she continued. “I think he’s trying to knock a hole in the wall. And why is he so big? I didn’t know woodpeckers got this big.”
Whenever someone talks about seeing a “big woodpecker” they have, by default, been looking at a pileated woodpecker. It’s the largest species still extant in North America. Charting out at roughly the size of a crow, it is actually several times larger than its closest-sized living cousin, the Northern Flicker. One larger relative to the pileated, the ivory-billed woodpecker, has not been verifiably sighted since the mid 1940’s and the species is presumed extinct.
The good news for my mother-in-law is that it was unlikely that her bird was working on a way into her living room. That heavy, loud drumming is more typical of a pileated woodpecker letting everyone know it’s around. Cedar siding has a nice ring to it if you peck it just right.
The even better news was that Jackie’s sighting provided a teachable moment. If she didn’t know the pileated woodpecker even existed then she obviously had a lot to learn about birds. This was my foot in the door. After 35 years, I was finally able to prove to her that I knew at least something!. (I’m planning on getting her a field guide for her next birthday.)
When it comes to spotting woodpeckers it may be the best of times for suburban birders. The devastating work of the emerald ash borer that laid waste to nearly the entire population of one of our most populous trees inadvertently spawned a boom time for woodpeckers. The US Forest Service documented as early as 2013 an increase in number of several species of woodpeckers that feed on the larva of the invasive pest. Many other bird species have benefitted as well — from both the increased availability of nesting cavities (created in large part by the excavation of woodpeckers), as well as an increase in the availability of a whole host of additional insects that make their living off dead and dying trees.
Interestingly, the pileated woodpecker was not one of the species tracked in the population study, as they seemed to have no particular interest in eating the emerald ash borer. They did benefit, nevertheless, from the presence of millions of dead ash trees that provided wonderful conditions for the large woodpecker’s favorite food — carpenter ants. In the bird world, nothing spikes a population like an overabundance of food, and it doesn’t take long for most species to increase populations substantially when more than enough food is readily available.
Simple math follows: The more giant woodpeckers there are blasting large cavities into the sides of dead trees in search of ants, the more owls, squirrels, wood ducks and bats stand to benefit from increased housing opportunities.
Don’t think for a moment that I don’t share the same heartbreak of millions of Americans who have seen their beloved “first golden blush of fall” largely destroyed by the all-out invasion of the emerald ash borer. As invasive species go, this one has had an almost inconceivable effect on the hardwood forests of the Midwest.
What I am saying is that, while I wouldn’t go so far as to call it a “silver lining,” it is interesting to note that some native species may actually benefit, at least in the short term, when an “alien invasion” occurs. There are both winners and losers in this game and it’s not always easy to predict who the beneficiaries will be. That’s one of the wonders of the natural world, it always keeps us guessing.
Remember, if you have comments on this column or questions about the natural world please write The Rail Trail Naturalist, P.O. Box 170, Fredericksburg, OH 44627 or email John at jlorson@alonovus.com. You can also follow along on Instagram @railtrailnaturalist.