9509286 Lively Parasites can dramatically influence the behavior of their hosts. Such behavioral changes can sometimes benefit the parasite by increasing its probability of being transmitted to another host. Preliminary studies have demonstrated that a trematode parasite, Microphallus sp., causes of significant behavioral change in the freshwater snail, Potamopyrgus antipodarum. This research will experimentally determine if the behavioral change is simply a byproduct of parasitism, or if it is an adaptive strategy on the part of the parasite to increase the likelihood that infected snails are eaten by the final host in the life cycle, ducks. These ideas will be tested by determining the effect of food deprivation on the behavior of infected and uninfected snails, as well as determining the removal rates of infected snails from the population by waterfowl and predators that cannot serve as final hosts for the parasite. This study will be the first to begin to examine the interaction of host and non-host predators in shaping host-parasite relationships. These types of studies are important because models of parasite spread in populations usually assume that transmission is a random event. However, this clearly is not the case. Since many trematode parasites of snails also infect humans and domestic livestock as a final host, an understanding how the parasite affects the behavior of intermediate hosts may lead to better control measures.
