Solar radiation decreases parasitism in Daphnia

Erin P. Overholt, Spencer R. Hall, Craig E. Williamson, Claire K. Meikle, Meghan A. Duffy, Carla E. Cáceres

Research output: Contribution to journalArticlepeer-review


Climate change and variation in atmospheric ozone are influencing the intensity of ultraviolet radiation (UVR) reaching ecosystems. Changing UVR regimes, in turn, may alter epidemics of infectious disease. This possibility hinges on the sensitivity of epidemiologically relevant traits of host and parasite to UVR. We address this issue using a planktonic system (a zooplankton host, Daphnia dentifera, and its virulent fungal parasite, Metschnikowia bicuspidata). Controlled laboratory experiments, coupled with in situ field incubations of spores, revealed that quite low levels of UVR (as well as longer wavelength light) sharply reduced the infectivity of fungal spores but did not affect host susceptibility to infection. The parasite's sensitivity to solar radiation may underlie patterns in a lake survey: higher penetration of solar radiation into lakes correlated with smaller epidemics that started later in autumn (as incident sunlight declined). Thus, solar radiation, by diminishing infectivity of the parasite, may potently reduce disease.

Original languageEnglish (US)
Pages (from-to)47-54
Number of pages8
JournalEcology Letters
Issue number1
StatePublished - Jan 1 2012


  • Daphnia-Metschnikowia
  • Epidemic size
  • Host-parasite
  • Solar radiation
  • Ultraviolet

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics

Fingerprint Dive into the research topics of 'Solar radiation decreases parasitism in Daphnia'. Together they form a unique fingerprint.

Cite this