Skip to main content
SLU publication database (SLUpub)

Research article2014Peer reviewedOpen access

Fatal attraction: vegetation responses to nutrient inputs attract herbivores to infectious anthrax carcass sites

Turner, Wendy C.; Cromsigt, Joris; Stenseth, Nils Christian

Abstract

Parasites can shape the foraging behaviour of their hosts through cues indicating risk of infection. When cues for risk co-occur with desired traits such as forage quality, individuals face a trade-off between nutrient acquisition and parasite exposure. We evaluated how this trade-off may influence disease transmission in a 3-year experimental study of anthrax in a guild of mammalian herbivores in Etosha National Park, Namibia. At plains zebra (Equus quagga) carcass sites we assessed (i) carcass nutrient effects on soils and grasses, (ii) concentrations of Bacillus anthracis (BA) on grasses and in soils, and (iii) herbivore grazing behaviour, compared with control sites, using motion-sensing camera traps. We found that carcass-mediated nutrient pulses improved soil and vegetation, and that BA is found on grasses up to 2 years after death. Host foraging responses to carcass sites shifted from avoidance to attraction, and ultimately to no preference, with the strength and duration of these behavioural responses varying among herbivore species. Our results demonstrate that animal carcasses alter the environment and attract grazing hosts to parasite aggregations. This attraction may enhance transmission rates, suggesting that hosts are limited in their ability to trade off nutrient intake with parasite avoidance when relying on indirect cues.

Keywords

anthrax; camera traps; disease transmission; foraging ecology; host-pathogen contact; parasite avoidance

Published in

Proceedings of the Royal Society B: Biological Sciences
2014, Volume: 281, number: 1795, article number: 20141785

    Sustainable Development Goals

    SDG15 Life on land

    UKÄ Subject classification

    Forest Science
    Ecology

    Publication identifier

    DOI: https://doi.org/10.1098/rspb.2014.1785

    Permanent link to this page (URI)

    https://res.slu.se/id/publ/61352