May 21, 2013 1 Comment
Strange as it may seem to residents of the western U.S. or coastal areas in the east, one of my favorite sights in Missouri is dry sand! It’s a true rarity in our limestone/dolomite dominated state, a result of nearly continuously exposed land for the past several hundred million years. Only along the state’s bigger rivers, where relatively recent alluvial events have yet to be completely eroded by the passage of time, can significant sand deposits be found. It is in these habitats that one of my favorite of Missouri’s tiger beetles, Cicindela formosa generosa (Eastern Big Sand Tiger Beetle), can be found. In much of the state, tiny slivers of sand dry enough to support populations of these beetles occur sporadically along the Missouri and Mississippi Rivers and their larger tributaries. More extensive deposits, however, are found in several wide, low ridges of sand in the southeastern lowlands of the state—relatively recent alluvial deposits from the last glacial maximum. Sadly, in a region originally blanketed by tupelo/gum/cypress swamp, such relatively dry areas were the first to fall to the plow, and subsequent drainage of the surrounding swamps further promoted a near complete conversion of the entire region to agriculture.
Still, tiny remnants of original habitat remain—generally parcels of land that were either too dry and sandy or persistently undrainable. Such parcels now form the basis of Missouri’s system of preserves in southeast Missouri. As tiny as they are and representing only a few percent of their original extent, these parcels now serve a critical role in preserving some of Missouri’s most endangered natural communities. Among these is Sand Prairie Conservation Area in Scott Co., featured several times now on this blog (Sand Prairie Conservation Area, A sand prairie autumn). The sand here is extraordinarily dry, due not only to its depth but also the low organic content—factors that made the land unfarmable and, ultimately, allowed it to escape the conversion that befell the surrounding areas and eventually become a preserve. I have visited Sand Prairie many times in recent years, and although I now know its plants and animals well, there are some that I never tire of seeing—plants like clasping milkweed (Asclepias amplexicaulis), one of my favorite of Missouri’s milkweeds, and animals like C. formosa generosa!
Last weekend I visited Sand Prairie once again, and I was happy to see C. formosa generosa as plentiful as I have ever seen it. I have photographed this species on several occasions, most recently two years ago at a site very near my house. Those last photographs are probably as good as I can ever expect (and in fact one of them even made this year’s ESA calendar), so barring some unusual color form or interesting natural history observation I have little reason to continue taking photographs of it. Nevertheless, I’m trying out a new diffuser, which was all the excuse I needed to try my hand again with this big, beautiful species. I was once again reminded of why of I love this tiger beetle so much—their bulk, their bulging eyes, their long, looping escape flights that end with a comical bounce and tumble, only to end up on their feet and facing their pursuer. These beetles are loaded with personality and behavioral charisma. It was an unseasonably warm and humid day, so my opportunities to photograph them were limited. I hope these few that I present here impart some of that personality.
Copyright © Ted C. MacRae 2013