Abstract
Red-backed shrikes (Lanius collurio) behave quite differently towards two common nest predators. While the European jay (Garrulus glandarius) is commonly attacked, in the presence of the Eurasian magpie (Pica pica), shrikes stay fully passive. We tested the hypotheses that this passive response to the magpie is an alternative defense strategy. Nesting shrikes were exposed to the commonly attacked European kestrel (Falco tinnunculus) in a situation in which i) a harmless domestic pigeon, ii) a commonly attacked European jay, and iii) a non-attacked black-billed magpie are (separately) presented nearby. The kestrel dummy presented together with the magpie dummy was attacked with a significantly lower intensity than when it was presented with the other intruders (pigeon, jay) or alone. This means that the presence of the magpie inhibited the shrike’s defense response towards the other intruder. These results support our previous hypotheses that shrikes use an alternative defense strategy in the magpie’s presence. We hypothesize that the magpie is able to associate the active defense of the shrikes with the close proximity of a nest and that shrikes try not to draw the magpie’s attention to the nest. The reason why this strategy is not used against the jay remains unanswered as jays as well as magpies show very similar cognitive and foraging skills enabling them to individuate the nest presence according to active parental defense.
Highlights
Predator recognition and categorization is an essential cognitive ability enabling the optimization of antipredator behavior [1][2]
In concordance with our hypothesis, the kestrel dummy presented together with the magpie dummy was attacked with a significantly lower intensity than when it was presented with the other intruders or alone
Our new results further show that 1) shrikes are able to solve the MPC arisen from the cooccurrence of a predator, towards which the active nest defense is effective; and a predator, towards which the active nest defense is not effective; 2) shrikes are able to solve this MPC the predator towards which the active nest defense is effective represents a greater threat than the predator towards which the active nest defense is not effective
Summary
Predator recognition and categorization is an essential cognitive ability enabling the optimization of antipredator behavior [1][2]. Prey species may ignore the presence of a less dangerous predator [3], while it must choose the appropriate antipredator behavior towards the specialized predators of adults or nests [4][5][6][7]. The red-backed shrike (Lanius collurio) shows a vigorously active nest defense behavior towards various predators and nest parasites [8][9] including humans [10]. PLOS ONE | DOI:10.1371/journal.pone.0159432 July 25, 2016
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
