Parasite predators exhibit a rapid numerical response to increased parasite abundance and reduce transmission to hosts

Ecology and Evolution

Skylar R. Hopkins²  Jennie A. Wyderko²  Robert R. Sheehy¹  Lisa K. Belden² 

[1] Department of Biology, Radford University, Radford, Virginia;Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia

关键词: Commensalism;    community dynamics;    disease ecology;    host–parasite interactions;    mutualism;   

DOI  :  10.1002/ece3.634

来源: Wiley

【 摘 要 】

Abstract

Predators of parasites have recently gained attention as important parts of food webs and ecosystems. In aquatic systems, many taxa consume free-living stages of parasites, and can thus reduce parasite transmission to hosts. However, the importance of the functional and numerical responses of parasite predators to disease dynamics is not well understood. We collected host–parasite–predator cooccurrence data from the field, and then experimentally manipulated predator abundance, parasite abundance, and the presence of alternative prey to determine the consequences for parasite transmission. The parasite predator of interest was a ubiquitous symbiotic oligochaete of mollusks, Chaetogaster limnaei limnaei, which inhabits host shells and consumes larval trematode parasites. Predators exhibited a rapid numerical response, where predator populations increased or decreased by as much as 60% in just 5 days, depending on the parasite:predator ratio. Furthermore, snail infection decreased substantially with increasing parasite predator densities, where the highest predator densities reduced infection by up to 89%. Predators of parasites can play an important role in regulating parasite transmission, even when infection risk is high, and especially when predators can rapidly respond numerically to resource pulses. We suggest that these types of interactions might have cascading effects on entire disease systems, and emphasize the importance of considering disease dynamics at the community level.

【 授权许可】

CC BY   
© 2013 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.