Seasonality of Diplostomum spathaceum (Trematoda: Strigeidae) transmission to brook trout (Salvelinus fontinalis) in northern Quebec, Canada

Abstract

The availability of cercariae of Diplostomum spathaceum, calculated as the product of the rate of cercarial release, the expected cercarial life span, and the prevalence of infection in snail host Lymnaea arctica, was determined between June and September at a pond near Schefferville in the Québec subarctic. Cercariae were present from late June until mid-September but were most abundant in July and August with a peak in early August. Cercarial availability coincided with the pattern of acquisition of metacercariae by sentinel fish (Salvelinus fontinalis).