Non-consumptive effects of spiders on herbivore and carnivore prey: occurrence, importance, and mechanisms
Final Report Abstract
In this project, we investigated antipredator behavior across spider and insect species of a wide taxonomic range. We tested how behavioral responses to chemotactile predator cues are affected by life-history traits of predator and prey, and how they cascades down to other trophic levels. Besides these predator-prey interactions based on chemotactile cues in spiders and insects, we also investigated competitor-competitor interactions based on chemotactile cues in ants. We found that antipredator behavior among terrestrial arthropods (here defined as change in movement pattern) is less widespread and harder to detect than expected from the literature. Out of >100 predator-prey species combinations, only eight showed significant antipredator behavior in laboratory experiments. However, certain species, notably the wood cricket Nemobius sylvestris responded to cues of spiders, and adjusted their behavior according to spider species, spider commonness and spider-cricket size ratio. In laboratory and field experiments involving insects and plants, spider cues reduced herbivory and significantly altered arthropod communities. Formica ants respond to chemically very different cues such as those of spiders and crickets, and probably use them to find prey. Ants also strongly responded to chemical cues of other ant species. Subordinate ants usually avoided cues of dominant ones, whereas dominant species either ignored or approached cues of subordinates. Our results indicate that ants are particularly well suited for the study of non-consumptive effects because of their intense chemical communication and the relatively well-known substances involved. Effects of ant chemical cues on other arthropods will be addressed in future research. Furthermore, interspecific interactions and co-occurrence patterns among ants, and hence community composition, may be strongly mediated by chemical cues. The importance of these cues for the success of invasive species will be addressed in a follow-up project.
Publications
- (2014): Effects of spider chemotactile cues on arthropod behavior. Journal of Insect Behavior 27: 567-580
Bucher R, Binz H, Menzel F & Entling MH
(See online at https://doi.org/10.1007/s10905-014-9449-1) - (2014): Knowing the risk: Crickets distinguish between spider predators of different size and commonness. Ethology 120: 99-110
Binz H, Bucher R, Entling MH & Menzel F
(See online at https://doi.org/10.1111/eth.12183) - (2014): The chemistry of competition: Exploitation of heterospecific cues depends on the dominance rank in the community. Animal Behaviour 94: 45-53
Binz H, Foitzik S, Staab F & Menzel F
(See online at https://doi.org/10.1016/j.anbehav.2014.05.024) - (2014): Trait-mediated effects between predators: ant chemical cues induce spider dispersal. Journal of Zoology 293: 119-125
Mestre L, Bucher R & Entling MH
(See online at https://doi.org/10.1111/jzo.12127) - Spider cues stimulate feeding, weight gain and survival of crickets. Ecological Entomology
Bucher R, Binz H, Menzel F & Entling MH
(See online at https://doi.org/10.1111/een.12131) - Plant choice, herbivory and weight gain of wood crickets under the risk of predation. Entomologia Experimentalis et Applicata, Vol 155 Issue 2, May 2015, Pages 148-153
Bucher R, Heinrich H & Entling MH
(See online at https://doi.org/10.1111/eea.12291) - Risk of spider predation alters food web structure and reduces local herbivory in the field. Oecologia, June 2015, Volume 178, Issue 2, pp 571–577
Bucher R, Menzel F & Entling MH
(See online at https://doi.org/10.1007/s00442-015-3226-5) - Sublethal effects of Imidacloprid on interactions in a tritrophic system of non-target species. Chemosphere Volume 132, August 2015, Pages 152-158
Uhl P, Bucher R, Schäfer RB & Entling MH
(See online at https://doi.org/10.1016/j.chemosphere.2015.03.027)
