title: Experimental warming drives a seasonal shift in the timing of host-parasite dynamics with consequences for disease risk.
abstract: Multi-species experiments are critical for identifying the mechanisms through which climate change influences population dynamics and community interactions within ecological systems, including infectious diseases. Using a host-parasite system involving freshwater snails, amphibians and trematode parasites, we conducted a year-long, outdoor experiment to evaluate how warming affected net parasite production, the timing of infection and the resultant pathology. Warming of 3 °C caused snail intermediate hosts to release parasites 9 months earlier and increased infected snail mortality by fourfold, leading to decreased overlap between amphibians and parasites. As a result, warming halved amphibian infection loads and reduced pathology by 67%, despite comparable total parasite production across temperature treatments. These results demonstrate that climate-disease theory should be expanded to account for predicted changes in host and parasite phenology, which may often be more important than changes in total parasite output for predicting climate-driven changes in disease risk.
authors.affiliation: Ecology and Evolutionary Biology Department, University of Colorado, Ramaley N122, UCB 334, Boulder, CO, 80305, USA.
authors.forename: Sara H
authors.initials: SH
authors.lastname: Paull
authors.forename: Pieter T J
authors.initials: PT
authors.lastname: Johnson
mesh_terms: D000663:Amphibians / Q000469:parasitology*; D000818:Animals; D006790:Host-Parasite Interactions / Q000502:physiology*; D006358:Hot Temperature; D010273:Parasitic Diseases, Animal / Q000469:parasitology / Q000473:pathology*; D011157:Population Dynamics; D012621:Seasons; D012908:Snails / Q000469:parasitology*; D014200:Trematoda / Q000502:physiology*
keywords: Amphibians; Ribeiroia ondatrae; climate change; community interactions; disease risk; malformations; mismatch; pathology; phenology; seasonality