Tuesday, August 4, 2009 - 10:50 AM

COS 32-9: Differences in aquatic communities within wetland reservoir subirrigation systems in northwestern Ohio

Peter C. Smiley Jr. and Barry J. Allred. USDA-ARS

Background/Question/Methods

Establishment of a water management system known as the wetland-reservoir subirrigation system (WRSIS) results in the creation of wetlands adjacent to agricultural fields.  Specifically, each WRSIS consists of one wetland designed to process agricultural chemicals (WRSIS wetlands) and one wetland to store subirrigation water (WRSIS reservoirs).  Previous research within three WRSIS constructed in the Maumee River watershed in northwestern Ohio has examined plants and aquatic animals in WRSIS wetlands, but not WRSIS reservoirs.  Our hypothesis was that the larger, deeper WRSIS reservoirs would have different aquatic vertebrate communities than the smaller, shallower WRSIS wetlands.  Fishes, amphibians, and reptiles were sampled by seining, hoop netting, and gee minnow trapping in three WRSIS wetlands and three WRSIS reservoirs in June of 2006, 2007, and 2008.  A blocked two factor ANOVA coupled with the Tukey test was used to determine if differences in community structure occurred between wetland types and years.

Results/Conclusions

No difference in species richness, abundance, or percent reptiles occurred between WRSIS wetlands and reservoirs.  Percent amphibians was greater in WRSIS wetlands than reservoirs (P < 0.05) and percent fishes was greater in WRSIS reservoirs than wetlands (P < 0.05).  Jaccard’s similarity index scores ranged from 0 to 0.5 and indicated species composition was different between WRSIS wetlands and reservoirs.  No differences in any response variable occurred among years.  Our results suggest that WRSIS may benefit wetland dependent vertebrates through the creation of different sized wetlands within agricultural watersheds.