Response of benthic macroinvertebrates to dam removal in the restoration of the Boardman River, Michigan, USA
Fig 2
Benthic macroinvertebrate data, summed from six Surber samples (0.093 m2) at each of 11 sites, and averaged at upstream, downstream, and formerly impounded (new channel) sites of the Brown Bridge Dam (removed in between 2012–2013) along the Boardman River, Michigan, USA.
Variables measured were: Invertebrates per square meter (A), taxon richness (family level, sometimes higher classification for non-insects) (B) and fraction of insects in orders Ephemeroptera, Plecoptera, and Trichoptera (%EPT) (C). Rectangles show mean +/- SE with mean dividing each rectangle. Points indicate measured values. Dashed line indicates time of dam removal. Due to large numbers of New Zealand mud snails (Potamopyrgus antipodarum) at all sites in later years, this taxon was excluded from summary variable calculations.