¬†¬†¬†¬† Last week my friend Kathy and I spent a happy, sunny day hiking in a Virginia state park known for its¬†long meadow vistas and forest trails.¬† As we walked, we delighted in a profusion of blooming bloodroot and scores of towering tulip poplars, tipped with last year’s dried ‘tulips.’
¬†¬†¬†¬†¬† But for me the greatest thrill was my introduction to caddisfly cases.¬† Now,¬†I love nature deeply, but I am not particularly knowledgeable in the natural sciences.¬† Kathy, however, is full of fascinating information about¬†many of the plants and animals we meet on our hikes.¬†
¬†¬†¬†¬† Kathy suggested we stop at a little stream that crossed the trail and see what we could see.¬† We knelt, lifted out a¬†large rock, and turned¬†it over.¬† Clinging to the underside was a¬†tiny caddisfly larva¬†case.¬† But only by looking through the magnifying glasses we had brought could we really see the tiny wonder in front of us.¬†¬†The case attached to the rock was astonishingly colorful.¬† It was made of the tiniest pebbles of red, white, black, and brown, all firmly held into a tiny cigar shape by silk the caddisfly larva had spun around itself and the bits of rock.¬†
¬†¬†¬†¬† Cleverly, the caddisfly larva protects itself during the fall, winter, and spring it spends¬†in the water by creating its own hard¬†case.¬† And as the larva grows during these months, it¬†enlarges its case with more debris and silk.¬†¬† When it is time to pupate, the caddisfly attaches both ends of its case to an object in the water, such as a rock.¬† Thus, the pupating animal is protected against predators, and water can still flow through the case.¬†¬†When the mature caddisfly is ready to emerge, it uses its special pair of mandibles to cut its way out of the case.
¬†¬†¬†¬†¬†Adult caddisflies seem to live to mate.¬† They do not eat at all.¬† After a week or two, or maybe longer, they die.¬†¬†The entire lifespan of a caddisfly is complete in a single year.
¬†¬†¬†¬† Seeing a caddisfly case was¬†not only a¬†visual treat, but¬†a good sign as well.¬†¬†Caddisflies, along with mayflies and stoneflies, are signs of at least a fairly good quality of water.–April Moore¬†¬†¬†