CHARACTERIZATION OF MACROINVERTEBRATE ABUNDANCE AND BIOMASS ASSOCIATED WITH 
DIFFERING WATERFOWL MANAGEMENT TREATMENTS IN THE LOWER MISSISSIPPI ALLUVIAL 
VALLEY.

Jack W. Grubaugh1, Darren W. Mitchell1, Catharina R. Grubaugh2, and Daniel B. 
Grubaugh2
1Department of Biology, University of Memphis, Memphis, TN 38152 2White Station 
Public Schools, Memphis, TN 38111.

Managers in the Lower Mississippi Alluvial Valley (LMAV) employ a variety of 
treatments to provide moist-soil seed crops and vegetation as food resources for 
migratory waterfowl. Little is known about macroinvertebrate communities 
associated with these management treatments, which may provide a secondarily 
important food resource for migrating waterfowl. We characterized benthic 
community abundance and biomass in four types of management treatments: 
permanent deep water (DE), fall flooded duck potato (DP), fall flooded millet 
(ML), and re-flooded shorebird management areas (SB). Aquatic worms 
(Oligochaeta) dominated abundance in all treatments, while biomass consisted 
primarily of oligochaetes, snails, midge larvae (Chironomidae), and aquatic 
larvae of the beetle Berosus. Abundance was significantly greatest under DE 
management (128,000/m2), followed by ML (58,000/m2) and SB (52,000/m2), and 
significantly least in DP (12,000/m2) areas. Standing stock biomass was very 
high in DE, ML, and SB treatments, with mean ash-free dry mass exceeding 10g/m2. 
Standing stocks noted in DP treatment areas still exceeded 4 g/m2. These results 
indicate that substantially large communities of macroinvertebrates are 
associated with waterfowl management areas in the LMAV. These communities 
represent a potentially important food resource, which, if not utilized during 
the fall waterfowl migration, may be available as a protein resource during the 
spring migration to the breeding grounds.

Keywords: aquatic macroinvertebrates, benthic communities, community 
composition, migratory waterfowl, Mississippi delta