Distribution and feeding behavior of early life stages of the northern shrimp, Pandalus borealis, in relation to the spring phytoplankton bloom in the western Gulf of Maine

The northern shrimp Pandalus borealis is a commercially important crustacean found in the deep waters of western Gulf of Maine. In order to develop better fisheries management practices, it is essential to understand variability in P. borealis recruitment. Analysis of samples collected along a coastal transect (during 2005 and 2006), indicate cross-shore distribution of early planktonic larval stages is consistent with observed benthic distribution of ovigerous females. Timing of larval occurrence in relation to the spring phytoplankton bloom suggests that a match/mismatch with abundance of phytoplankton and zooplankton prey may be a primary determinant of recruitment success. Among the potential zooplankton prey, Balanus sp. larvae are predominant during the residence time of P. borealis larvae. Laboratory feeding experiments revealed stage III larvae have higher feeding rates on the diatom Thalassiosira nordenskioeldii than stage I. These results support efforts for coupled physical biological models that will allow testing of recruitment hypotheses.