Interactions of multiple predators with different foraging modes in an aquatic food web

Abstract

Top predators can have different foraging modes that may alter their interactions and effects on food webs. Interactions between predators may be non-additive resulting from facilitation or interference, whereas their combined effects on a shared prey may result in emergent effects that are risk enhanced or risk reduced. To test the importance of multiple predators with different foraging modes, we examined the interaction between a cruising predator (largemouth bass, Micropterus salmoides) and an ambush predator (muskellunge, Esox masquinongy) foraging on a shared prey (bluegill sunfish, Lepomis macrochirus) with strong anti-predator defense behaviors. Additive and substitution designs were used to compare individual to combined predator treatments in experimental ponds. The multiple predator interaction facilitated growth of the cruising predator in the combined predator treatments, whereas predator species had substitutable effects on the growth of the ambush predator. The combined predator treatments created an emergent effect on the prey; however, the direction was dependent on the experimental design. The additive design found a risk-reducing effect, whereas the substitution design found a risk-enhancing effect for prey fish. Indirect effects from the predators weakly extended to lower trophic levels (i.e., zooplankton community). Our results highlight the need to consider differences in foraging mode of top predators, interactions between predators, and emergent effects on prey to understand food webs.

The importance of intraguild predation in predicting emergent multiple predator effects

“…1) likely explained the substitutable effects they had on Pardosa survival. This risk reduction is predicted to arise when prey escape both predators, which engage in IGP, or when predators simply interfere with one another (Vance-Chalcraft and Soluk 2005, Schmitz 2007, Carey and Wahl 2010; however, Tigrosa and Scarites never consumed one another. Alternatively, Pardosa may use compensatory defenses (e.g., reduced activity) to minimize mortality from predators differing in the level of risk they pose and in habitat domain (Krupa and Sih 1998).…”

A Generalist Protist Predator Enables Coexistence in Multitrophic Predator-Prey Systems Containing a Phage and the Bacterial Predator Bdellovibrio

“…Early investigations focused on pairwise predatorprey interactions that were then generalized to complete communities under the assumption that multiple pairwise interactions had additive effects (Oksanen et al, 1981;Wootton, 1994). Later, laboratory and field studies focused on predation by multiple species and mostly observed the effects of a pair of predators on one shared prey (Sih et al, 1998;Schmitz, 2007;Carey and Wahl, 2010). However, trophic interactions in nature are highly complex (Polis, 1991;Martinez, 1992;Lafferty et al, 2006), and even in environments consisting of only a limited number of species, a prey may interact with about 10 different predators (Polis, 1991).…”

Predator–prey interactions mediated by prey personality and predator hunting mode

“…However, to date there have been few studies that have explored the relationship between predator hunting mode/domain and prey mortality (e.g. [36][37][38]), and none that have incorporated prey personality. Here, we examine the interactive roles of prey personality and predator hunting mode in governing predation risk within a simple food web.…”