Common trail insects of Big Bend National Park

Big Bend National Park, the United States' twenty-seventh national park, was established by Congress on June 12, 1944, setting aside 708,221 acres of desert and mountain terrain to protect for future generations (Jameson 1996). Selected for its dramatic scenery, geologic features, and unique plant and animal communities, it also provides the best example of Chihuahuan Desert ecology in the United States (Maxwell 1968, Wauer 1973). Although the Chihuahuan Desert is the largest of the three creosotebush dominated deserts in North America, it is also the least understood (Brown 1994).

Entomologists estimate over 5,000 species of insects occur within Big Bend National Park. Yet only about 4,000 have been identified, and only a handful of the many orders have been studied with any thoroughness (Van Pelt 1995, Wauer 1973). The first large, general study of insects in Big Bend National Park was made by R. H. Baker in 1937 as a background study for the proposed national park. Subsequent studies have been confined mostly to specific orders, families, or genera with the exception of Van Pelt's 1995 armotated inventory of insects in the park (Van Pelt 1995). However, this work is based on secondary sources and has no insect descriptions or photographs. In fact, with the exception of Roland Wauer's recent Butterflies of West Texas Parks and Preserves, there have been no field guides on the insects of Big Bend Nafional Park (Wauer 2002).

The purpose of the present study is to provide an easy-to-use field guide for the layperson as an aid in identifying commonly encountered insects in the park. It focuses on some of the higher-profile, "charismatic," or easily noficed insects that a casual visitor stopping at highly frequented areas within the park is likely to see. In addition to aiding in insect identification, this guide is intended to be educational in providing information on insect distribution, habitat, and behavior. In helping people become more familiar with the world of desert invertebrates, 1 hope that this guide will foster a broader ecological understanding of desert environments and ultimately encourage conservation of our natural resources.