Marine pelagic rotifers and tintinnids - important trophic links in the spring plankton community of the Gullmar Fjord, Sweden

Abstract

During the winter and spring of 1981, the dynamics of a marine pelagic rotifer, Synchaeta vorax Rousselet and tintinnids of the genus Tintinnopsis, were studied in the Gullmar Fjord on the Swedish west coast. Although present in February and March, it was not until early April when the surface water temperature exceeded 6°C that the rotifer population started to grow rapidly. Thereafter, the population increased exponentially for 6 weeks. Estimates of consumption of phytoplankton by rotifers and tintinnids in their most dynamic phase approximated to that of the phyto-plankton production. Lack of data on the amount of detritus available and the number of young rotifers passing the 90 μm net are however obvious limitations in such calculations. Nevertheless, the results indicate that the tintinnids and the rotifers are highly important components in the area's spring plankton community. Through high turnover rates, they are able to utilize effectively the spring phytoplankton bloom and thus serve as a link between the primary and the larger secondary producers. © 1983 IRL Press Ltd.