Marine zooplankton of Coronation Gulf and Bathurst Inlet, Nunavut, Canada

Here we report a survey of marine zooplankton in Coronation Gulf and Bathurst inlet located in the Kitikmeot Region of Nunavut, Canada. Zooplankton were collected at nineteen stations with a 236 pro mesh net in September 2007. The zooplankton samples were examined for species composition, abundance and spatial heterogeneity. Taxa were characteristic of the Arctic zooplankton fauna but not distributed homogeneously. Overall, from west to east, the abundance of cyclopoid and harpacticoid copepods decreased as calanoid copepods increased. Multivariate cluster analysis revealed 5 sub-groups based on species composition and abundance which are located in West, Central, and Eastern Coronation Gulf, and mid- and southern Bathurst Inlet. The West group had three stations and a high number of the cyclopoid copepods Oithona similis and Triconia borealis. The Central group contained six stations, which were distinguished as having a mixture of Oithona and juvenile Pseudocalanus as well as high percentage of Calanus juveniles. One station of the Central group was found in northeastern Dolphin and Union Strait likely tracing the outflow of water from Coronation Gulf. The Eastern group had a high number of Pseudocalanus and Acartia juveniles. Acartia hudsonica, Eurytemora, and Tortanus discaudatus were found in Bathurst Inlet in association with conditions created by riverine freshwater input. Also, a high number of bivalve veligers were observed in the southern reaches of Bathurst Inlet. This report describes a heterogeneous distribution of typical Arctic zooplankton taxa in the region and serves as a baseline from which to measure change.