Flight Lines: Little discoveries on the North Dakota prairie
"I doubt it."
That was my answer to the question, "Do you think these caterpillars are eating lichens?" Sure there were quite a few of them crawling on the large lichen-encrusted rocks on a beautiful piece of native prairie south of Woodworth last weekend, but the idea just didn't fit the paradigm I had of moth and butterfly caterpillars.
Self respecting lepidopteran larvae are supposed to eat leafy plants, I reasoned. Stuff like willows, hackberries, stinging nettles, and milkweeds are supposed to facilitate the tremendous growth of caterpillars. No, the critters couldn't possibly be eating something as low in nutrition as lichens.
I couldn't have been more wrong.
It turned out someone in our group had a smart phone and - from the very spot we were standing - quickly ascertained that indeed there exists lichen-eating caterpillars. Not only that but the ones we were finding were determined to be larvae of painted lichen moths (Hypoprepia fucosa), beautiful creatures in their own right.
We continue methodically with the morning's damp-from-rain stroll on top of the Missouri Coteau in central North Dakota. A chilly west wind hustles along low scuddy clouds still holding a few hints of rain. Shoulders are hunched up, heads turned down, and hats pulled just a little bit tighter on heads.
A rich tapestry of native grasses and forbs rolls out before us like a multi-hued green carpet. Needle and thread grass is thankfully still green and not mysteriously and painfully drilling itself into our socks, something the seed is wont to do later in summer. Blue-eyed grass flower buds (actually an iris) are noted, patiently awaiting the appearance of sunshine before revealing their six-petaled sky-blue brilliance. The pink wispy seed heads of prairie smoke reveal we have missed the strange flower actually in bloom.
Headlining the bird show this morning are pairs of willets and upland sandpipers, shorebirds that centuries ago determined the grassy prairies of the upper Great Plains to be ideal sites upon which to raise families.
Prairie landscapes seem best suited, however, for sparrows. Several sparrow species carve out territories from this grassy landscape then spend summers eating invertebrates and rearing young. Something curious the prairie sparrows share is the sometimes frustrating ability to sound like insects. Virtually the entire suite of grassland sparrows sings with what most references inevitably describe as, "an insect-like trill or buzz."
Farther up a modest slope a tiny flutter of wings explodes from nearly beneath my feet. An examination of the immediate area reveals a carefully hidden grassy depression holding six little eggs, the hope and future of a pair of grasshopper sparrows. We take photos, tidy up the area, and step away.
It's too cold for much in the way of bugs to be flying. Instead the cold-blooded insects are hunkered down in the soggy grass patiently awaiting the life giving warmth of the sun. Somehow someone in our group discovers a lethargic dragonfly hidden in heavy cover. The kindly fellow even knows what it is, a dot-tailed whiteface (Leucorrhinia intacta), yet another species I hadn't seen before.
Amble through virtually any landscape with a careful purpose and it begins to reveal itself. Slowly and methodically layers of nature's magic begin to emerge if one commits some time. A snapshot won't do it. No, this requires a movie, a slow motion one.
The pace of our 21st century lives accelerates daily with faster processors in our cell phones, more Internet bandwidth, drive-thru fast foods, and so it goes. We may very well have the largest widescreen TV in the neighborhood but we are definitely missing the big picture.
Every time I step outside I'm in a classroom. Often I fail to pay attention to the teacher; I have to hustle to work after all. Given the chance, though, I take a deliberate approach and inhale my surroundings in careful exacting breaths. It's only with a slow systematic process do the lessons of nature become learned. Whether in cypress swamps, mountainous alpine zones, coastal dunes or our own back yards, something will inevitably surprise us. Who would have thought that caterpillars would eat lichen for instance?