Advancing an Ecosystem Approach in the Gulf of Maine

Results of a Collaborative Project to Observe Coastal Zooplankton and Ichthyoplankton Abundance and Diversity in the Western Gulf of Maine: 2003–2008

Jeffrey A. Runge and Rebecca J. Jones


Abstract .—In a collaborative project with a number of New England commercial fishermen, zooplankton was sampled two to three times a month between 2003 and 2005 at the GoMOOS (Gulf of Maine Ocean Observing System) Buoy “B” and between 2003 and 2008 at a station on Jeffreys Ledge in the western Gulf of Maine. Additionally, during 2007 and 2008 zooplankton and ichthyoplankton were sampled semimonthly at stations located in Massachusetts Bay and Ipswich Bay, New Hampshire. The authors report here on seasonal and interannual patterns in biomass, diversity, and abundance in the zooplankton at the Jeffreys Ledge station and in the ichthyoplankton at the Massachusetts and Ipswich Bay stations. Notable is the dominance of Calanus finmarchicus on Jeffreys Ledge and the dramatic decline in summer abundance of this species between 2003 and 2005, perhaps related to a shift to lower salinity water during this same period. Interannual differences in timing of peak abundance, and in species dominance of ichthyoplankton, were observed between 2007 and 2008. While these time series provide information and insight about change in the coastal planktonic communities in the western Gulf of Maine, currently there are no observing programs that sample coastal communities at frequency sufficient to show seasonal and interannual change in this region.