Periodic and Resident Components in Communities of Atlantic Fishes

Abstract

From trawling at least monthly on a station in Passamaquoddy Bay, N.B., four groups of species were distinguished. One group of species was present on station during winter only, another group in summer only, and a third group was present throughout the year. A fourth group of species was present only occasionally. This type of temporal component structure was found in previously published data for stations with similar habitat but at different latitudes and different temperature regimes. With increased annual temperature fluctuation by locality, there were proportionately more species in the periodic components and fewer in the regular component. Comparable tropical communities had very small periodic components.