Warming can impact consumer–resource interactions through multiple mechanisms. For example, warmi... more Warming can impact consumer–resource interactions through multiple mechanisms. For example, warming can both alter the rate at which predators consume prey and the rate prey develop through vulnerable life stages. Thus, the overall effect of warming on consumer–resource interactions will depend upon the strength and asymmetry of warming effects on predator and prey performance. Here, we quantified the temperature dependence of both (a) density‐dependent predation rates for two dragonfly nymph predators on a shared mosquito larval prey, via the functional response, and (b) the development rate of mosquito larval prey to a predator‐invulnerable adult stage. We united the results of these two empirical studies using a temperature‐ and density‐dependent stage‐structured predation model to predict the effects of temperature on the number of larvae that survive to adulthood. Warming accelerated both larval mosquito development and increased dragonfly consumption. Model simulations suggest that differences in the magnitude and rate of predator and prey responses to warming determined the change in magnitude of the overall effect of predation on prey survival to adulthood. Specifically, we found that depending on which predator species prey were exposed to in the model, the net effect of warming was either an overall reduction or no change in predation strength across a temperature gradient. Our results highlight a need for better mechanistic understanding of the differential effects of temperature on consumer–resource pairs to accurately predict how warming affects food web dynamics. A free plain language summary can be found within the Supporting Information of this article.
Warming can impact consumer–resource interactions through multiple mechanisms. For example, warmi... more Warming can impact consumer–resource interactions through multiple mechanisms. For example, warming can both alter the rate at which predators consume prey and the rate prey develop through vulnerable life stages. Thus, the overall effect of warming on consumer–resource interactions will depend upon the strength and asymmetry of warming effects on predator and prey performance. Here, we quantified the temperature dependence of both (a) density‐dependent predation rates for two dragonfly nymph predators on a shared mosquito larval prey, via the functional response, and (b) the development rate of mosquito larval prey to a predator‐invulnerable adult stage. We united the results of these two empirical studies using a temperature‐ and density‐dependent stage‐structured predation model to predict the effects of temperature on the number of larvae that survive to adulthood. Warming accelerated both larval mosquito development and increased dragonfly consumption. Model simulations suggest...
Changes in predator diversity via extinction and invasion are increasingly widespread and can hav... more Changes in predator diversity via extinction and invasion are increasingly widespread and can have important ecological and socio-economic consequences. Anticipating and managing these consequences requires understanding how predators shape ecological communities. Previous predator biodiversity research has focused on post-colonization processes. However, predators can also shape communities by altering patterns of prey habitat selection during colonization. The sensitivity of this non-consumptive top down mechanism to changes in predator diversity is largely unexamined. To address this gap, we examined patterns of dipteran oviposition habitat selection in experimental aquatic habitats in response to varied predator species richness while holding predator abundance constant. Caged predators were used in order to disentangle behavioural oviposition responses to predator cues from potential post-oviposition consumption of eggs and larvae. We hypothesized that because increases in pred...
The global resurgence and emergence of new mosquito-borne diseases and increasing resistance of m... more The global resurgence and emergence of new mosquito-borne diseases and increasing resistance of mosquitoes to chemical pesticides have prompted renewed interest in biocontrol methods that use aquatic predators of mosquito larvae. For disease vectors with complex life cycles, like mosquitoes, in which adults are terrestrial and choose aquatic habitats in which to deposit their offspring, shifts in oviposition site selection may have important consequences for vector population dynamics and epidemiology. While there have been numerous studies of mosquito oviposition site selection, methodology and results vary, making it difficult to evaluate the general importance of predator-induced shifts in oviposition site selection for biocontrol scenarios. Here we use meta-analysis to provide a quantitative framework for examining variation in mosquito oviposition responses to predators. Overall, we find a broad pattern of predator avoidance among mosquito and predator taxa. The primary factor ...
Predators can play an important role in regulating prey abundance and diversity, determining food... more Predators can play an important role in regulating prey abundance and diversity, determining food web structure and function, and contributing to important ecosystem services, including the regulation of agricultural pests and disease vectors. Thus, the ability to predict predator impact on prey is an important goal in ecology. Often, predators of the same species are assumed to be functionally equivalent, despite considerable individual variation in predator traits known to be important for shaping predator–prey interactions, like body size. This assumption may greatly oversimplify our understanding of within-species functional diversity and undermine our ability to predict predator effects on prey. Here, we examine the degree to which predator–prey interactions are functionally homogenous across a natural range of predator body sizes. Specifically, we quantify the size-dependence of the functional response of African clawed frogs (Xenopus laevis) preying on mosquito larvae (Culex ...
The Comparative Functional Response Approach (CFRA) was developed to provide a practical methodol... more The Comparative Functional Response Approach (CFRA) was developed to provide a practical methodology by which short-term experiments can be used to forecast the longer-term impacts of a potential invading consumer. The CFRA makes inferences about potential invader impact based on comparisons of the functional responses of invader and native consumers on native resources in a common experimental venue. Application of the CFRA and derivative approaches have proliferated since it was introduced in 2014. Here we examine the conceptual foundations of the CFRA within the context of basic Lotka–Volterra consumer-resource theory. Our goals are to assess whether core predictions of the CFRA hold within this framework, to consider the relative importance of background mortality and consumer assimilation efficiency in determining predator impact, and to leverage this conceptual framework to expand the discussion regarding stability and long term consumer and resource dynamics. The CFRA asserti...
Warming can impact consumer–resource interactions through multiple mechanisms. For example, warmi... more Warming can impact consumer–resource interactions through multiple mechanisms. For example, warming can both alter the rate at which predators consume prey and the rate prey develop through vulnerable life stages. Thus, the overall effect of warming on consumer–resource interactions will depend upon the strength and asymmetry of warming effects on predator and prey performance. Here, we quantified the temperature dependence of both (a) density‐dependent predation rates for two dragonfly nymph predators on a shared mosquito larval prey, via the functional response, and (b) the development rate of mosquito larval prey to a predator‐invulnerable adult stage. We united the results of these two empirical studies using a temperature‐ and density‐dependent stage‐structured predation model to predict the effects of temperature on the number of larvae that survive to adulthood. Warming accelerated both larval mosquito development and increased dragonfly consumption. Model simulations suggest that differences in the magnitude and rate of predator and prey responses to warming determined the change in magnitude of the overall effect of predation on prey survival to adulthood. Specifically, we found that depending on which predator species prey were exposed to in the model, the net effect of warming was either an overall reduction or no change in predation strength across a temperature gradient. Our results highlight a need for better mechanistic understanding of the differential effects of temperature on consumer–resource pairs to accurately predict how warming affects food web dynamics. A free plain language summary can be found within the Supporting Information of this article.
Warming can impact consumer–resource interactions through multiple mechanisms. For example, warmi... more Warming can impact consumer–resource interactions through multiple mechanisms. For example, warming can both alter the rate at which predators consume prey and the rate prey develop through vulnerable life stages. Thus, the overall effect of warming on consumer–resource interactions will depend upon the strength and asymmetry of warming effects on predator and prey performance. Here, we quantified the temperature dependence of both (a) density‐dependent predation rates for two dragonfly nymph predators on a shared mosquito larval prey, via the functional response, and (b) the development rate of mosquito larval prey to a predator‐invulnerable adult stage. We united the results of these two empirical studies using a temperature‐ and density‐dependent stage‐structured predation model to predict the effects of temperature on the number of larvae that survive to adulthood. Warming accelerated both larval mosquito development and increased dragonfly consumption. Model simulations suggest...
Changes in predator diversity via extinction and invasion are increasingly widespread and can hav... more Changes in predator diversity via extinction and invasion are increasingly widespread and can have important ecological and socio-economic consequences. Anticipating and managing these consequences requires understanding how predators shape ecological communities. Previous predator biodiversity research has focused on post-colonization processes. However, predators can also shape communities by altering patterns of prey habitat selection during colonization. The sensitivity of this non-consumptive top down mechanism to changes in predator diversity is largely unexamined. To address this gap, we examined patterns of dipteran oviposition habitat selection in experimental aquatic habitats in response to varied predator species richness while holding predator abundance constant. Caged predators were used in order to disentangle behavioural oviposition responses to predator cues from potential post-oviposition consumption of eggs and larvae. We hypothesized that because increases in pred...
The global resurgence and emergence of new mosquito-borne diseases and increasing resistance of m... more The global resurgence and emergence of new mosquito-borne diseases and increasing resistance of mosquitoes to chemical pesticides have prompted renewed interest in biocontrol methods that use aquatic predators of mosquito larvae. For disease vectors with complex life cycles, like mosquitoes, in which adults are terrestrial and choose aquatic habitats in which to deposit their offspring, shifts in oviposition site selection may have important consequences for vector population dynamics and epidemiology. While there have been numerous studies of mosquito oviposition site selection, methodology and results vary, making it difficult to evaluate the general importance of predator-induced shifts in oviposition site selection for biocontrol scenarios. Here we use meta-analysis to provide a quantitative framework for examining variation in mosquito oviposition responses to predators. Overall, we find a broad pattern of predator avoidance among mosquito and predator taxa. The primary factor ...
Predators can play an important role in regulating prey abundance and diversity, determining food... more Predators can play an important role in regulating prey abundance and diversity, determining food web structure and function, and contributing to important ecosystem services, including the regulation of agricultural pests and disease vectors. Thus, the ability to predict predator impact on prey is an important goal in ecology. Often, predators of the same species are assumed to be functionally equivalent, despite considerable individual variation in predator traits known to be important for shaping predator–prey interactions, like body size. This assumption may greatly oversimplify our understanding of within-species functional diversity and undermine our ability to predict predator effects on prey. Here, we examine the degree to which predator–prey interactions are functionally homogenous across a natural range of predator body sizes. Specifically, we quantify the size-dependence of the functional response of African clawed frogs (Xenopus laevis) preying on mosquito larvae (Culex ...
The Comparative Functional Response Approach (CFRA) was developed to provide a practical methodol... more The Comparative Functional Response Approach (CFRA) was developed to provide a practical methodology by which short-term experiments can be used to forecast the longer-term impacts of a potential invading consumer. The CFRA makes inferences about potential invader impact based on comparisons of the functional responses of invader and native consumers on native resources in a common experimental venue. Application of the CFRA and derivative approaches have proliferated since it was introduced in 2014. Here we examine the conceptual foundations of the CFRA within the context of basic Lotka–Volterra consumer-resource theory. Our goals are to assess whether core predictions of the CFRA hold within this framework, to consider the relative importance of background mortality and consumer assimilation efficiency in determining predator impact, and to leverage this conceptual framework to expand the discussion regarding stability and long term consumer and resource dynamics. The CFRA asserti...
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