No description available.

Salmincola edwardsii is an ectoparasitic copepod typically found on the gills of brook trout (Salvelinus fontinalis). Laboratory experiments were conducted to determine: (i) the effects of temperature and photoperiod on early life cycle events, and (ii) the rate of larval development to adult. Egg incubation time, duration of copepodid swimming activity and copepodid survival time all decreased with increasing temperature. Different photoperiods had no effect. Hatching duration and hatching success were not influenced by either temperature or photoperiod. Copepodids remained alive and active for up to 16 days at 8$ sp circ$ and 5 days at 20$ sp circ$C. Adult male copepods were observed at 3 to 8 days after host exposure. They lived for up to 3 days. Adult females became permanently attached to hosts between 11 and 16 days post-infection.

No description available.

No description available.

The brook trout population in a 4.7 hectare subarctic lake was sampled in 1986 and intensively fished in 1987, 1988 and 1989 in order to study the effect of stock depletion on fish parasite transmission. Population density was originally high, with slow individual growth rates, and small maximum size. Brook trout bore infections of Eubothrium salvelini, Phyllodistomum umblae, Crepidostomum farionis and Diplostomum sp. as well as some rare parasites. After intensive fishing the growth rates and size of the remaining fish increased. In 1987 all parasites increased in abundance. E. salvelini decreased in 1988 whereas the abundance of the other parasites remained high. In 1989 two new parasites, Echinorhynchus lateralis and Philonema sp. appeared. Parasite community changes and improves fish growth were related to trout diets and the pattern of intermediate host consumption. In 1987 zooplankton feeding increased. It then declined in 1988 and 1989 as populations of large benthic invertebrate prey increased. Feeding shifts may also have been mediated in part by intraspecific competition and aggression.

No description available.