Kim N. Mouritsen, Alexander Gorbushin and K. Thomas Jensen, 1999. Influence of trematode infections on in situ growth rates of Littorina littorea.

J.Mar.Biol.Ass.UK, 79, 425-430

Abstract: The influence of various species of digenean trematodes on the growth rates of Littorina littorea (L.) (Gastropoda: Prosobranchia) from different habitats was investigated using a new and accurate method for in situ measurements of growth. The main results showed (1) that infections either reduced or had no effect on growth in comparison with uninfected snails, (2) that growth rates of infected specimens were significantly correlated with the degree of parasitic castration, (3) that the same type of infection could have differential effect on growth depending on habitat/population from where the snails originated. The results are discussed in the context of the life-history hypothesis and variation in general food availability as possible explanations for the accumulating equivocal evidence for parasite-induced gigantism in gastropods.