Benthic Habitats and the Effects of Fishing

Symposium Abstract: Sampling Macrozoobenthos from Zebra Mussel Communities in Lake Erie

G. W. Kennedy, M. C. Fabrizzio, M. A. Blouin, and J. F. Savino

doi: https://doi.org/10.47886/9781888569605.ch27

Macrozoobenthos found on hard substrate areas in central Lake Erie were examined as part of a larger study to understand the use of nearshore areas by larval and juvenile fishes. Large portions of nearshore habitats were colonized in the 1990’s by dreissenid mussels, Dreissena polymorphya (zebra mussel) and Dreissena bugensis (quagga mussel), which makes standard sampling methods for benthos largely ineffective. To provide quantitative collection of macrozoobenthic organisms inhabiting these hard substrate areas, we developed a method involving the use of SCUBA and underwater suction sampling. One-quarter m2 quadrats were sampled using a submersible suction sampler to collect free-ranging macrozoobenthos, followed by collection of dreissenid mussels within the quadrat immediately afterward. Comparisons were made of the benthos collected by suction with the benthos remaining among the mussels to determine the effectiveness of the suction sampling method. Preliminary estimates show that over 90% of the total number of organisms and over 95% of the total taxa in each 0.25 m2 area were collected by suction sampling. Relationships between the benthos taxa and the dreissenid mussels and density of mussel populations are currently being examined. These data are critical for determining the relationship and linkages between juvenile fishes and invertebrate prey found in these altered Great Lakes habitats.