Parasite communities of two three-spined stickleback (Gasterosteus aculeatus) populations : effects of a local-scale host introduction?

Abstract

The introduction of new hosts into new habitats can bring along hitchhiking parasites, i.e. parasites being introduced with the host. This in particular can be an important dispersal mechanism for autogenic parasites that are otherwise restricted by the natural movement of their fish hosts.

In this study, the effect of a local host introduction on the parasite communities of three-spined sticklebacks in two subarctic lakes, was examined by comparing the parasite communities of the “introduced” (Takvatn), versus that of the “founder” (Sagelvvatn) population. Seasonal variation and inter-lake differences in abundance was also integrated in the study.

The study revealed great similarity between the parasite communities du to similar ecosystems, close geographical proximity, and the facts that the only two autogenic stickleback specialists present in the systems had been introduced with its host. The subtle differences in parasite species richness were explained by accidental infections of parasites of sympatric fish species.