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Bay of Fundy Associated Investigators: Related Web Sites: Related Time Series: Zooplankton are sampled every 2-4 weeks at Prince 5, which is a 100 m deep station located just off Campobello Island in the northwest of the Bay of Fundy, approximately 6 km offshore from St Andrews, New Brunswick. Vertical tows are made from near-bottom to surface using a ringnet (0.75 m diameter, 200 µm mesh). A small vessel is used as the sampling platform. Conductivity, temperature, and depth (CTD) profiles are recorded, and water samples are collected in Niskin bottles for measuring phytoplankton, nutrients, and extracted chlorophyll. Zooplankton samples are split, and one-half is used for wet-dry weight determination. The other half is subsampled for taxonomic identification and enumeration. Biomass of the dominant groups is also calculated using individually determined dry weights and abundance data for the dominant species groups (Calanus, Oithona, Pseudocalanus, and Metridia). The data are entered into the BioChem database at the Canadian Department of Fisheries and Oceans (DFO). An ecosystem status report on the state of phytoplankton and zooplankton in Canadian Atlantic waters is prepared every year. Monthly average abundance of total copepods is variable, but values are generally lowest during winter (January-April) and highest in late summer/autumn (August-October). Annual average copepod abundance anomalies were highest in 2001 and 2006, and lowest in 2002 and 2005 (Figure 20). In years of low abundance, i.e. years with negative annual abundance anomalies, the summer/autumn high abundance period was often weaker and/or of shorter duration. In addition to copepod abundance, co-sampled time-series of total zooplankton wet weight, integrated chlorophyll, and integrated temperature data were available for the site (Standard Co-sampled Variables Plot). Although the seasonal cycles of copepod abundance and total wet weight are similar, the annual anomalies of total wet weight differ slightly as a result of the influence of phytoplankton blooms contaminating the measurement. Chlorophyll concentrations demonstrate a seasonal cycle similar to that of the copepods, but preceding it by one month, and the annual chlorophyll concentrations have demonstrated a slight downward trend over time. At-site sampled integrated temperature and Reynolds SST show similar interannual increases and decreases, but differ slightly in seasonal cycle, most probably caused by the larger spatial region represented by the Reynolds data. The SST values are at the high end of an approximately 50-year multidecadal trend (Standard Long-term Comparison Plot). Within this region, water temperatures are often correlated with the state of the North Atlantic Oscillation (NAO). At this time, any relationship between water temperature and zooplankton abundance is inconclusive. |