| Popis: |
Dispersal is ubiquitous in animals, shaping natural populations' ecological and evolutionary patterns. In freshwater ecosystems, the drift or downstream movement of animals (e.g., macroinvertebrates) carried by water current might be modulated by parasites and their seasonal occurrence. However, most studies on parasite modulation of host drifting behavior have focused on acanthocephalans, and other parasites like microsporidians have been largely neglected. The present study provides new insight into seasonal and dial amphipod drift modulation by microsporidian parasites. Experiments employing drift nets took place in a German stream in October 2021, April, and July 2022. Ten microsporidians were identified, expanding current knowledge of host-parasite interaction in Gammarus pulex clade E by five interactions. The prevalence and composition of microsporidian parasites varied seasonally, between day and night, and between drifted and stationary amphipods. Prevalence was generally higher in drifted amphipods than stationary ones. These changes were linked to host size and population dynamics. However, in two parasites, the prevalence was highest during the daytime suggesting changes in host phototaxis likely related to the parasite’s mode of transmission. Alterations in drifting behavior may have important implications for amphipods population dynamics and microsporidians' dispersal. The underlying mechanisms are more complex than previously thought. |
