title: Summer time predation on the obligatory off-host stage of an invasive ectoparasite.
abstract: Predation can regulate populations and strongly affect invasion success of novel prey. The deer ked (Lipoptena cervi; Linnaeus 1758) is an invasive ectoparasite of cervids that spends a long period of its life cycle outside the host. Prior to this study, virtually nothing was known about natural summer time predation on the deer ked. We aimed to evaluate the magnitude of summer time predation on L. cervi pupae in different habitats and to identify potential predators. We conducted a set of field experiments, where we exposed L. cervi pupae to various ground-dwelling vertebrate and invertebrate predators. The loss of pupae was monitored for different predator guilds. Three habitats of the moose, the main host species, were studied: (1) moist heath forest; (2) dry, logged heath forest; and (3) moist meadow. The results indicate notable summer time predation on L. cervi pupae, and the pupal predation varied within and between habitats, being lowest in the meadow habitat. We found a positive correlation between pupal loss and abundance of the common lizard (Zootoca vivipara), harvestmen (Opiliones), ground spiders (Gnaphosidae) and Formicinae-ants. We conclude that summer time predation during the pupal phase can have a notable local importance for the L. cervi abundance.
authors.affiliation: Department of Environmental and Biological Sciences,University of Eastern Finland,P.O. Box 111,FI-80101 Joensuu,Finland.
authors.forename: Sirpa
authors.initials: S
authors.lastname: Kaunisto
authors.affiliation: Department of Environmental and Biological Sciences,University of Eastern Finland,P.O. Box 111,FI-80101 Joensuu,Finland.
authors.forename: Ilkka
authors.initials: I
authors.lastname: Raunismaa
authors.affiliation: Department of Environmental and Biological Sciences,University of Eastern Finland,P.O. Box 111,FI-80101 Joensuu,Finland.
authors.forename: Raine
authors.initials: R
authors.lastname: Kortet
authors.affiliation: Department of Biological and Environmental Science,University of Jyväskylä,Konnevesi Research Station,P.O. Box 35,FI-40014 Jyväskylä,Finland.
authors.forename: Hannu
authors.initials: H
authors.lastname: Ylönen
mesh_terms: D000818:Animals; D001000:Ants; D003670:Deer / Q000469:parasitology; D004175:Diptera / Q000254:growth & development* / Q000502:physiology*; D004478:Ectoparasitic Infestations; D008116:Lizards; D011235:Predatory Behavior; D011679:Pupa / Q000502:physiology; D012621:Seasons; D013112:Spiders
keywords: Cervidae; Hippoboscidae; ectoparasitism; population regulation; predator; pupa; summer survival