Friday, August 31, 2012
They still seem like newcomers, and why shouldn’t they? Here in Central Missouri, we never “see” them—unless you count their poor bodies lying lifeless—like overturned baskets—on the roadsides.
Poor critters . . . cars are so rude.
And to people north of the Missouri River, they truly are newcomers; the river serves as a serious barrier to their northward expansion. Each time a few of them manage to get across the river here and there, and begin new population centers, a hard winter eradicates them from the whole region. Or, that’s what people have thought.
Armadillos are insectivores, and they don’t hibernate. A hard winter that freezes the ground and prevents them from getting to delicious, hibernating insects wipes them out. It hits the “restart” button, and when that happens, Missouri has few, if any, armadillos until immigrants of that species, expanding from firm populations south of us, replenish the species in our state.
In 1959, when Charles and Elizabeth Schwartz published the first edition of The Wild Mammals of Missouri (a book I could not live without), armadillos were not known to live in our state. By the time they first revised the book, in 1981, the Schwartzes listed the armadillo as “possibly occurring.” By 2001, when Elizabeth Schwartz presented to our state the second revised edition—an endlessly fascinating guidebook, textbook, encyclopedia, and lavishly, perfectly illustrated volume—armadillos had definitely become established as “full residents,” “having been collected in 66 counties.”
So the armadillo is no longer just the “state bird of Texas”!
Dr. Lynn Robbins and his students at Missouri State University have for decades studied the range expansion of these curious critters, which so many of us still equate with the Longhorn State, and not the Show-Me State. Here’s a request for citizens to help with their studies; this appeared in the March 1993 issue of the Missouri Conservationist (the official monthly publication of the Missouri Department of Conservation):
So Why Am I Writing about Armadillos Today?
Well, Sue and I have been hiking recently at Painted Rock Conservation Area, south of Jefferson City along the Osage River where it bends (at Osage Bend), and we were astonished to see several armadillos abroad in daylight. It was midafternoon, and they were wandering around in the leaf litter, in the oak-hickory forest, foraging constantly.
What does a foraging armadillo look like? Nose-to-ground! Their conical heads poke through the leaf litter, snout-first, and the rest of the body follows. They plow through the fallen leaves in a random zigzag path, leaving a rounded tunnel behind. The leaves atop the “tunnel,” parted by the body, fall back together somewhat, but you can see through them to the ’dillo trail.
Armadillos specialize in eating insects (though they opportunistically eat other little critters, as well). They whiffle along the ground, snuffling for grubs, beetles, ants, and whatever else. They dig into the earth as far as six inches to locate a juicy insect their noses have detected.
It’s really interesting to watch them. They have terrible vision and next-to-terrible hearing, so they tend not to notice if they’re being observed. I think the constant crunching of dry leaves around their heads drowns out the sound of voices and footsteps.
Apparently, armadillos have been remarkably active this summer in general. One of my friends thinks it’s armadillos that have been rooting up her garden over at Osage Bluff.
They’re supposed to be mostly nocturnal during the summer—so why are they out in daylight?
It appears to be environmental: Remember last winter, when it never really got to be truly “winter”? Presumably a large number of armadillos survived Missouri’s winter last year. During our usual cold, freezing winters, many of them simply perish. Even in good years, they don’t put on much body fat to shiver away to stay alive—and any mammal that doesn’t hibernate has to “stoke the fires” of life in freezing weather by “eating hearty.” Frozen ground is not conducive to digging. So many ’dillos die.
But it was hardly even cold last winter, so we probably had record numbers of armadillos survive until springtime. Then we had a nice wet spring (remember?) and plenty of insects had survived the mild winter, too. Things were looking up for the armadillos at that point—but then the drought set in.
I suppose the drought is doing to the armadillos what winter failed to do—limit the populations. By the end of August, insects have become hard to find, and so has water. The armadillos are close to starving—and that’s why they’re out during the day, even, hunting relentlessly for bugs, grubs, beetles, weevils, pupae, lizards, darn near anything, to eat.
I recently contacted Dr. Robbins with my hypothesis, and responding in an e-mail of August 27, 2012, he said he thinks I’m on the right track. He mentioned, however, that many armadillos do seem to be surviving our midwestern winters—somehow, decent numbers of them manage to find shelter and food, so the idea of them all perishing with cold weather is not as strict as once supposed. That they’ve been continuously present in Nebraska for fifteen years, he says, “leads me to believe that even if a high percentage do not make it through a winter, they do find refuges where they can find enough food to make it.” They don’t seem to “fatten up” before winter, but they seem to survive anyway, by finding “large amounts of food under the leaf litter and by digging in unfrozen ground.”
Regarding what we saw at Painted Rock, and the drought, Dr. Robbins noted, “If the drought continues, I too will be concerned, and the conditions you observed are similar to the way they [the armadillos] looked after the [recent] big snow event, including their frantic behavior to catch up. I have been seeing increasing numbers of road kills north of the Missouri River this summer.” He continued, “if there is a reduction in food as a carryover from this drought, it could be a problem.”
(Thank you, Dr. Robbins, for helping me understand this interesting animal, and for your work in helping humanity to understand many kinds of mammals, too!)
So there you have it—although Sue and I were thrilled to see our first ever—living—armadillos, the situation wasn’t optimal for all parties. I hate the thought of anything suffering. Let’s hope the rain is bringing them some relief.
Bonus info! The scientific name for the nine-banded armadillo is Dasypus novemcinctus. Dasypus is the genus name for our armadillo and is used for six other closely related (living) armadillo species as well. (Dasypodidae is the name for the whole armadillo family, which comprises about 21 species, in various genera.) Dasypus means “rough-footed.” Since armadillos are diggers by trade, they have coarse, sturdy feet!
The only species of armadillo found in the United States is the nine-banded armadillo, Dasypus novemcinctus. The second half of the name means “nine-banded” (“novem-” for “nine,” and “-cinctus” for “belted”—as in “cincture,” an encircling belt, or to “cinch” up something).
SPECIAL THANK YOU to Susan Ferber, who took all the great photos in this post and has graciously allowed me to use them on my blog. Not only is she a talented and skilled photographer, but also: She is the best person in the world to go hiking with!