title: Threat-sensitive anti-predator defence in precocial wader, the northern lapwingVanellus vanellus.
abstract: Birds exhibit various forms of anti-predator behaviours to avoid reproductive failure, with mobbing-observation, approach and usually harassment of a predator-being one of the most commonly observed. Here, we investigate patterns of temporal variation in the mobbing response exhibited by a precocial species, the northern lapwing (Vanellus vanellus). We test whether brood age and self-reliance, or the perceived risk posed by various predators, affect mobbing response of lapwings. We quantified aggressive interactions between lapwings and their natural avian predators and used generalized additive models to test how timing and predator species identity are related to the mobbing response of lapwings. Lapwings diversified mobbing response within the breeding season and depending on predator species. RavenCorvus corax, hooded crowCorvus cornixand harriers evoked the strongest response, while common buzzardButeo buteo, white storkCiconia ciconia, black-headed gullChroicocephalus ridibundusand rookCorvus frugileguswere less frequently attacked. Lapwings increased their mobbing response against raven, common buzzard, white stork and rook throughout the breeding season, while defence against hooded crow, harriers and black-headed gull did not exhibit clear temporal patterns. Mobbing behaviour of lapwings apparently constitutes a flexible anti-predator strategy. The anti-predator response depends on predator species, which may suggest that lapwings distinguish between predator types and match mobbing response to the perceived hazard at different stages of the breeding cycle. We conclude that a single species may exhibit various patterns of temporal variation in anti-predator defence, which may correspond with various hypotheses derived from parental investment theory.
authors.affiliation: Department of Avian Biology and Ecology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Królikowska
authors.affiliation: Department of Avian Biology and Ecology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Szymkowiak
authors.affiliation: School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ UK ; South Iceland Research Centre, University of Iceland, Bankavegi, IS-800 Selfoss, Iceland.
authors.forename: Rebecca Anne
authors.initials: RA
authors.lastname: Laidlaw
authors.affiliation: Department of Avian Biology and Ecology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland.
authors.forename: Lechosław
authors.initials: L
authors.lastname: Kuczyński
keywords: Harm to offspring hypothesis; Parental investment theory; Predator recognition; Reproductive value of offspring hypothesis