The Zooplankton of Tanquary Fjord, Ellesmere Island, with Special Reference to Calanoid Copepods

Abstract

Tanquary Fjord is ice-covered for a large part of the summer and hence very unproductive. The zooplankton showed variation between the years 1963 and 1964 both in abundance and in species composition, suggesting an unstable system. Development rates and breeding cycles of the calanoid copepods were indicated by the numbers in the various developmental stages. Two forms of Pseudocalanus, differing in the relation of urosome to cephalothorax length, were found. It is unknown whether the two forms are reproductively isolated. The dominant form has a biennial life cycle. Microcalanus pygmaeus appeared to breed biennially. The species Calanus glacialis and C. hyperboreus were shown to be opportunistic breeders; they developed to maturity over a period of several years.