Benthic invertebrate community composition and sediment properties in Barnegat Bay, New Jersey, 1965-2014

Abstract

Extended time series of estuarine benthic community composition and the chemical and physical properties of sediment are necessary for distinguishing natural variation from possible anthropogenic influences, such as EUtrophication. In July 2012, 2013, and 2014, 97 stations, randomly located throughout the Barnegat Bay-Little Egg Harbor estuary, were sampled. Benthic invertebrates were abundant, and the community was, in general, highly diverse. Although there was considerable spatial variability in sediment-particle sizes throughout the estuary, overall the total organic carbon content of the sediments was low (<1%). Comparable historical data from 1965-2010 are spotty in spatial and temporal coverage, limiting comparisons to these recent data. Where comparisons can be made, the abundance and species composition of the benthos and the sediment properties, show few changes in 45 years. Despite high nutrient loading to this coastal bay, its shallow depth and general lack of stratification lead to relatively high dissolved oxygen levels, and it seems likely that heterotrophs in the sediments, both EUkaryotes and prokaryotes, are rapidly metabolizing organic matter as it is produced.