SURVEY OF AQUATIC MACROINVERTEBRATES OF A NATIONAL WETLAND AREA IN BASTROP COUNTY, TEXAS

The Lost Pines Ecoregion in East Central Texas is an ecologically unique area composed of a diverse set of terrestrial and aquatic organisms, many of which are on the western edge of their ranges within Texas. We assessed the diversity, abundance, and occurrence of aquatic invertebrates in small wetland ponds located on the Griffith League Ranch, a relatively intact remnant area of the Lost Pines. Seventeen ponds were sampled for aquatic invertebrates and abiotic wetland pond characteristics (e.g., wetland pond size and hydroperiod) from February 2006 to January of 2007. The most common taxa found in all ponds were in the family Chironomidae (Diptera) and the most diverse invertebrate group in the area was the family Dytiscidae (Coleoptera), which was composed of 20 genera. Differences in species composition between small ponds and large ponds were noted, such that many of the taxa present in smaller more ephemeral ponds were in general not present in larger and more permanent ponds. The difference in species composition between small and large ponds highlights the need for different conservation strategies for managing ephemeral systems within a landscape to maintain regional diversity. In addition, this information will serve as critically important baseline data to assess the potential effects of the intense and widespread 2011 Bastrop Complex Fire on the wetland communities in this region.