Summer zooplankton distributions at the surface of the outer Bay of Fundy, eastern Canada

Copepods and cladocerans were collected, mainly in August, from the top 0.25 m of the water column in the outer Bay of Fundy, off Brier Island, Nova Scotia (ca. 44°15′N, 66°23′W) in 1975–1978, Deer Island, New Brunswick (ca. 45°00′N, 67°00′W) in 1977–1978, and Grand Manan Island, New Brunswick (ca. 44°40′N, 66°43′W) in 1981. In 1975–1977, the dominant species at the surface off Brier Island were stage CIV-I Calanus finmarchicus and CVI-V Pseudocalanus sp. The copepods Acartia spp., Anomalocera pattersonii, Centropages sp., Eurytemora spp., and Oithonia similis and the cladocerans Evadne sp. and Podon sp. also occurred regularly. The relative abundance of Calanus finmarchicus declined during the period July–October 1976, though the proportion of stages CVI-V increased. The relative proportions of Pseudocalanus sp., and of its stages CVI-V, both declined during the same period. The community at the surface was similar to that collected in other studies from subsurface tows in the Bay of Fundy as a whole, including Brier, Deer, and Grand Manan islands. This was not true of Brier Island in 1978: CVI-V Calanus finmarchicus predominated, and other species were scarce. Our samples from Deer and Grand Manan islands resembled those from Brier Island in 1978, though CVI-V Calanus finmarchicus predominated even more strongly. We discuss the differences between our samples from Brier Island in 1978 and 1975–1977, and between the latter and our New Brunswick data. However, there is no obvious explanation for most of these anomalies.