title: The trophic responses of two different rodent-vector-plague systems to climate change.
abstract: Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change.
authors.affiliation: State Key Laboratory of Integrated Management on Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
authors.affiliation: Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Blindern, Oslo 0316, Norway.
authors.forename: Boris V
authors.initials: BV
authors.lastname: Schmid
authors.affiliation: Inner Mongolia Center for Endemic Disease Control and Research, Huhehot 010031, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Inner Mongolia Center for Endemic Disease Control and Research, Huhehot 010031, People's Republic of China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Si
authors.affiliation: Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Blindern, Oslo 0316, Norway n.c.stenseth@ibv.uio.no.
authors.forename: Nils Chr
authors.initials: NC
authors.lastname: Stenseth
authors.affiliation: State Key Laboratory of Integrated Management on Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China zhangzb@ioz.ac.cn.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002681:China; D057231:Climate Change; D004196:Disease Outbreaks / Q000662:veterinary; D004197:Disease Reservoirs; D017753:Ecosystem; D005849:Gerbillinae / Q000382:microbiology* / Q000469:parasitology; D007303:Insect Vectors; D008954:Models, Biological; D010930:Plague / Q000453:epidemiology / Q000382:microbiology*; D011156:Population Density; D015995:Prevalence; D012376:Rodent Diseases / Q000453:epidemiology / Q000382:microbiology; D012589:Sciuridae / Q000382:microbiology* / Q000469:parasitology; D005423:Siphonaptera / Q000382:microbiology; D015010:Yersinia pestis
keywords: Yersinia pestis; bottom-up effect; climate change; structural equation model; top-down effect; trophic cascade model