Kirtland's Warbler: A superhero without a cape
(Imagine dramatic movie music playing.)
"These trees are dying! Who can save us from the scourge of the jack pine budworm? Can anyone help?"
"Look! It's a bird! It's not a plane! It's ... Kirtland's Warbler to the rescue!"
Yeah, we're being dramatic here, but not overly so. That's because if you've been in the jack pine recently, you may have noticed that some jack pine and red pine trees are turning brown and look like they are dying. That's because the trees are being damaged by an outbreak of jack pine budworm.
The budworm is the larvae of a moth that doesn't really have a name other than its scientific name -- Choristoneura pinus. It seems odd that the moth would be better known by the immature version of itself, but it's that immature version -- the larvae -- that makes this species significant.
The jack pine budworm is always present in the jack pine forests, but it's also cyclical. Outbreaks occur every six to 12 years or so, and right now we are in the second year of an outbreak that started in 2022.
A jack pine budworm outbreak is bad news for jack pines because, according to the Michigan DNR, the budworms "feed off needles on jack pine and red pine trees, leaving trees defoliated and causing die-back among the crowns of trees. Clipped and damaged needles turn reddish brown in early July, making the damage very apparent. Over time, rain and wind remove the dead needles, leaving trees with a bare, grayish appearance."
We've had conversations with skeptics who have wondered why the state and federal governments would spend so much money and put so much effort into saving a bird from extinction. What difference does one bird make? Well, a jack pine budworm outbreak makes a pretty compelling case for saving the Kirtland's.
Jack pine is a commodity. Timber companies want to buy the highest quality product possible. Jack pine budworms damage the tops of trees, stunting growth and lowering their value.
Kirtland's Warblers, meanwhile, love to eat jack pine budworms and feed them to their young. Birds in general are opportunistic eaters. If there's a jack pine budworm outbreak it just means there's more to go around. Ultimately, by eating the budworms, the Kirtland's Warblers help control the outbreak and limit the damage to the marketable trees. Without the birds doing the work for them, the state and federal governments might be forced to use chemicals to control the outbreaks. And that's something to be avoided because there are all kinds of unintended consequences with that.
The attached video seems to show a Kirtland's Warbler with two jack pine budworms in his beak. (We say "seems" because we're not 100 percent certain. But they sure look like jack pine budworm larvae.) The late Ron Austing captured the video, and it is likely that that male Kirtland's was on his way to feed his offspring.
The Kirtland's Warbler has always been special to us because it's just a cool bird. It's rare, it lives in an usual place, and it has an unusual life story. And on top of all of that, it's also a superhero.
Thank you, Kirtland's Warblers!