Data collected in 2009-2012 to assess benthic macroinvertebrate response to dike removal on the Nisqually River delta

Macroinvertebrate and environmental data were collected annually in July-August in the year before dike removal (2009) and the first three years after dike removal (2010-2012) at the Nisqually River Delta, Washington, U.S.A. Data were collected along a gradient extending from the inner marsh edge to the delta front and spanning different types of habitat including marsh restored to tidal inundation by dike removal, previously restored marsh, undisturbed reference marsh, and tidal flats. Biological data comprised benthic macroinvertebrate species composition, abundance, and biomass. Environmental correlates included bed elevation; sediment grain size, organic content, and pH; and water column temperature, salinity, and dissolved oxygen.