Thursday, August 5, 2010

PS 81-127: Aquatic insects of the Chihuahuan Desert grasslands

Diana V. Hernandez and Jerry L. Cook. Sam Houston State University

Background/Question/Methods The Chihuahuan Desert grasslands comprise about twenty percent of the entire Chihuahuan desert and are ecologically as well as economically important (Basurto and Hadley 2006). Although, the grasslands comprise a relatively small portion of the Chihuahuan Desert, their presence is vital for the subsistence of the ecoregion’s biological diversity. The grasslands support critical ecological processes, possess high levels of endemism, and sustain a high diversity of plants and animals (Aguirre et al. 2007). However, the Chihuahuan Desert grasslands have deteriorated since the mid 1800’s, both in Mexico and the USA, mostly as a consequence of deficient agricultural practices, climate change, fire suppression, habitat fragmentation and land use change. These factors have resulted in increased land erosion and reduced rain water absorption, biodiversity loss, invasive species, and reduced amounts of available forage for wild and domestic animals (Aguirre et al. 2007). Biodiversity loss is one of the most severe global environmental problems, mostly fostered by the destruction and fragmentation of natural ecosystems. Therefore, it’s important for us to begin biodiversity inventories that completely identify and describe the invertebrate fauna inhabiting unique ecosystems such as the Chihuahuan Desert grasslands. The objective of this study is to report the results of an inventory of aquatic insect species associated with the grasslands and scrublands in the Chihuahuan Desert region. Aquatic insects were collected during the summer of 2009 within four different sites which consisted mostly of freshwater rivers, streams, and pozas (pools).

Results/Conclusions

This study will be the first survey to describe the aquatic entomofauna currently inhabiting the Chihuahuan Desert grasslands. Identification of the specimens is in progress and we expect to find new aquatic insect species to be further described as well as new geographical records for several aquatic insect families. In terms of conservation of the Chihuahuan Desert grasslands, this study will be an important contribution to the overall ecological knowledge of the region.