Coleoptera Indicator Species in Wet vs. Dry Climate Regimes in Three Southwestern Georgia Wetland Types
Smith, Nathalie D.
Golladay, Stephen W.
MetadataShow full item record
Yearly variation in water availability has a profound effect on the presence and abundance of aquatic Coleoptera (beetles), particularly those dependent upon intermittent or seasonally inundated aquatic habitats. Thirty-four depressional wetlands, previously characterized as marshes, savannas or forested swamps, were sampled during above average and below average rainfall periods (1997-1998 and 2006-2007 respectively). Using Indicator Species Analysis, Coleoptera species were associated with wetland type and hydrologic regime linked to rainfall trends. Relying on species indicator values (p<0.05), marshes contained significantly higher numbers of indicator species compared to other wetland types during both wet and dry periods. Several indicator taxa were consistent within wetland type during the same hydrologic period, but these similarities were not consistent when compared across hydrologic regimes. Species diversity was higher during years with below normal rainfall. These findings indicate that marshes provide more suitable habitat and provide refugia that allow for survival and recovery beetle populations during unusually dry and wet periods. Faced with intermittent aquatic habitat and climate variation, Coleoptera taxa vary in life history characteristics and dispersal abilities which allow long term persistence within the larger landscape.