Distribution and feeding of the carnivorous copepod Paraeuchaeta norvegicain habitats of shallow prey assemblages and midnight sun

Paraeuchaeta norvegica was found to be widely distributed in the Norwegian Sea. They were least abundant in north-western areas, but otherwise no clea r horizontal patterns appeared with respect to latitude, longitude or water mass. Females and males had similar vertical distributions. The highest co ncentrations of adults occurred at 400-500 in depth; they largely avoided t he upper 50-100 in, even at night. Stages CIV and CV lived shallower in the water column than the adults, with the highest concentration between 100 a nd 300 in. Stages CII-CIII were most abundant at 50-100 m, while CI was dis tributed slightly deeper (maxima at 100 200 in). Potential prey were most a bundant in the upper 100 in; i.e. shallower than P. norvegica. Numbers of f ecal pellets produced by freshly collected adult females were relatively lo w (estimated at 0.7 pellets per individual on average for the entire sea), with maximal numbers for individuals captured in shallow waters. This sugge sts food limitation during summer, when food is concentrated in upper water s, and short and light nights limit nocturnal access to the shallow food re sources. Pellets mainly contained copepod remains.