1
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Lozano‐Huntelman NA, Bullivant A, Chacon‐Barahona J, Valencia A, Ida N, Zhou A, Kalhori P, Bello G, Xue C, Boyd S, Kremer C, Yeh PJ. The evolution of resistance to synergistic multi-drug combinations is more complex than evolving resistance to each individual drug component. Evol Appl 2023; 16:1901-1920. [PMID: 38143903 PMCID: PMC10739078 DOI: 10.1111/eva.13608] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 06/26/2023] [Accepted: 10/04/2023] [Indexed: 12/26/2023] Open
Abstract
Multidrug antibiotic resistance is an urgent public health concern. Multiple strategies have been suggested to alleviate this problem, including the use of antibiotic combinations and cyclic therapies. We examine how adaptation to (1) combinations of drugs affects resistance to individual drugs, and to (2) individual drugs alters responses to drug combinations. To evaluate this, we evolved multiple strains of drug resistant Staphylococcus epidermidis in the lab. We show that evolving resistance to four highly synergistic combinations does not result in cross-resistance to all of their components. Likewise, prior resistance to one antibiotic in a combination does not guarantee survival when exposed to the combination. We also identify four 3-step and four 2-step treatments that inhibit bacterial growth and confer collateral sensitivity with each step, impeding the development of multidrug resistance. This study highlights the importance of considering higher-order drug combinations in sequential therapies and how antibiotic interactions can influence the evolutionary trajectory of bacterial populations.
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Affiliation(s)
| | - Austin Bullivant
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Jonathan Chacon‐Barahona
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Alondra Valencia
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Nick Ida
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - April Zhou
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Pooneh Kalhori
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Gladys Bello
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Carolyn Xue
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Sada Boyd
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Colin Kremer
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
| | - Pamela J. Yeh
- Department of Ecology and Evolutionary BiologyUniversity of California, Los AngelesLos AngelesCaliforniaUSA
- Santa Fe InstituteSanta FeNew MexicoUSA
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2
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Rojas E, Prosnier L, Pradeau A, Boyer N, Médoc V. Anthropogenic noise does not strengthen multiple-predator effects in a freshwater invasive fish. JOURNAL OF FISH BIOLOGY 2023; 102:1470-1480. [PMID: 37029524 DOI: 10.1111/jfb.15397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 04/03/2023] [Indexed: 06/09/2023]
Abstract
Anthropogenic noise has the potential to alter community dynamics by modifying the strength of nested ecological interactions such as predation. Direct effects of noise on per capita predation rates have received much attention but the context in which predation occurs is often oversimplified. For instance, many animals interact with conspecifics while foraging and these nontrophic interactions can positively or negatively influence per capita predation rates. These effects are often referred to as multiple-predator effects (MPEs). The extent to which noise can modulate MPEs and thereby indirectly alter per capita predation remains unknown. To address this question, we derived the relationship between per capita predation rate and prey density, namely the functional response (FR), of single and pairs of the invasive topmouth gudgeon Pseudorasbora parva when feeding on water fleas under two noise conditions: control ambient noise estimated at 95 dB re 1 μPa and ambient noise supplemented with motorboat sounds whose relative importance over ambient noise ranged from 4.81 to 27 dB. In addition, we used video recordings to track fish movements. To detect MPEs, we compared the observed group-level FRs to predicted group-level FRs inferred from the individual FRs and based on additive effects only. Regardless of the number of fish and the noise condition, the FR was always of type II, showing predation rate in a decelerating rise to an upper asymptote. Compared to the noiseless condition, the predation rate of single fish exposed to noise did not differ at high prey densities but was significantly lower at low prey densities, resulting in an FR with the same asymptote but a less steep initial slope. Noise also reduced fish mobility, which might explain the decrease in predation rate at low prey densities. Conspecific presence suppressed the individual response to noise, the FRs of two fish (observed group-level FRs) being perfectly similar between the two noise conditions. Although observed and predicted group-level FRs did not differ significantly, observed group-level FRs tended to fall in the low range of predicted group-level FRs, suggesting antagonism and a negative effect of nontrophic interactions on individual foraging performance. Interestingly, the difference between predicted and observed group-level FRs was not greater with noise, which means that noise did not strengthen MPEs. Our results show that when considering the social context of foraging, here through the presence of a conspecific, anthropogenic noise does not compromise foraging in the invasive P. parva.
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Affiliation(s)
- Emilie Rojas
- Equipe Neuro-Ethologie Sensorielle (ENES), Centre de Recherche en Neurosciences de Lyon (CRNL), INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université Jean Monnet - Saint-Etienne, Saint-Etienne, France
| | - Loïc Prosnier
- Equipe Neuro-Ethologie Sensorielle (ENES), Centre de Recherche en Neurosciences de Lyon (CRNL), INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université Jean Monnet - Saint-Etienne, Saint-Etienne, France
| | - Aurélie Pradeau
- Equipe Neuro-Ethologie Sensorielle (ENES), Centre de Recherche en Neurosciences de Lyon (CRNL), INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université Jean Monnet - Saint-Etienne, Saint-Etienne, France
| | - Nicolas Boyer
- Equipe Neuro-Ethologie Sensorielle (ENES), Centre de Recherche en Neurosciences de Lyon (CRNL), INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université Jean Monnet - Saint-Etienne, Saint-Etienne, France
| | - Vincent Médoc
- Equipe Neuro-Ethologie Sensorielle (ENES), Centre de Recherche en Neurosciences de Lyon (CRNL), INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université Jean Monnet - Saint-Etienne, Saint-Etienne, France
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3
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Heterogeneity of interaction strengths and its consequences on ecological systems. Sci Rep 2023; 13:1905. [PMID: 36732566 PMCID: PMC9895049 DOI: 10.1038/s41598-023-28473-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 01/19/2023] [Indexed: 02/04/2023] Open
Abstract
Ecosystems are formed by networks of species and their interactions. Traditional models of such interactions assume a constant interaction strength between a given pair of species. However, there is often significant trait variation among individual organisms even within the same species, causing heterogeneity in their interaction strengths with other species. The consequences of such heterogeneous interactions for the ecosystem have not been studied systematically. As a theoretical exploration, we analyze a simple ecosystem with trophic interactions between two predators and a shared prey, which would exhibit competitive exclusion in models with homogeneous interactions. We consider several scenarios where individuals of the prey species differentiate into subpopulations with different interaction strengths. We show that in all these cases, whether the heterogeneity is inherent, reversible, or adaptive, the ecosystem can stabilize at a new equilibrium where all three species coexist. Moreover, the prey population that has heterogeneous interactions with its predators reaches a higher density than it would without heterogeneity, and can even reach a higher density in the presence of two predators than with just one. Our results suggest that heterogeneity may be a naturally selected feature of ecological interactions that have important consequences for the stability and diversity of ecosystems.
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4
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Morris JR, Perfecto I. An aggressive nonconsumptive effect mediates pest control and multipredator interactions in a coffee agroecosystem. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2653. [PMID: 35543106 PMCID: PMC9788006 DOI: 10.1002/eap.2653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 02/15/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Natural pest control is an alternative to pesticide use in agriculture, and may help to curb insect declines and promote crop production. Nonconsumptive interactions in natural pest control that historically have received far less attention than consumptive interactions, may have distinct impacts on pest damage suppression and may also mediate positive multipredator interactions. Additionally, when nonconsumptive effects are driven by natural enemy aggression, variation in alternative resources for enemies may impact the strength of pest control. Here we study control of the coffee berry borer (CBB), Hypothenemus hampei, by a keystone arboreal ant species, Azteca sericeasur, which exhibits a nonconsumptive effect on CBB by throwing them off coffee plants. We conducted two experiments to investigate: (1) if the strength of this behavior is driven by spatial or temporal variability in scale insect density (an alternative resource that Azteca tends for honeydew), (2) if this behavior mediates positive interactions between Azteca and other ground-foraging ants, and (3) the effect this behavior has on the overall suppression of CBB damage in multipredator scenarios. Our behavioral experiment showed that nearly all interactions between Azteca and CBB are nonconsumptive and that this behavior occurs more frequently in the dry season and with higher densities of scale insects on coffee branches. Our multipredator experiment revealed that borers thrown off coffee plants by Azteca can survive and potentially damage other nearby plants but may be suppressed by ground-foraging ants. Although we found no non-additive effects between Azteca and ground-foraging ants on overall CBB damage, together, both species resulted in the lowest level of plant damage with the subsequent reduction in "spillover" damage caused by thrown CBB, indicating spatial complementarity between predators. These results present a unique case of natural pest control, in which damage suppression is driven almost exclusively by nonconsumptive natural enemy aggression, as opposed to consumption or prey behavioral changes. Furthermore, our results demonstrate the variability that may occur in nonconsumptive pest control interactions when natural enemy aggressive behavior is impacted by alternative resources, and also show how these nonconsumptive effects can mediate positive interactions between natural enemies to enhance overall crop damage reduction.
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Affiliation(s)
- Jonathan R. Morris
- School for Environment and SustainabilityUniversity of MichiganAnn ArborMichiganUSA
| | - Ivette Perfecto
- School for Environment and SustainabilityUniversity of MichiganAnn ArborMichiganUSA
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5
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Buxton M, Cuthbert RN, Basinyi PL, Dalu T, Wasserman RJ, Nyamukondiwa C. Cattle dung in aquatic habitats alters mosquito predatory biocontrol dynamics. FOOD WEBS 2022. [DOI: 10.1016/j.fooweb.2022.e00241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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McCoy MW, Hamman E, Albecker M, Wojdak J, Vonesh JR, Bolker BM. Incorporating nonlinearity with generalized functional responses to simulate multiple predator effects. PeerJ 2022; 10:e13920. [PMID: 35999847 PMCID: PMC9393008 DOI: 10.7717/peerj.13920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 07/28/2022] [Indexed: 01/19/2023] Open
Abstract
Predicting the combined effects of predators on shared prey has long been a focus of community ecology, yet quantitative predictions often fail. Failure to account for nonlinearity is one reason for this. Moreover, prey depletion in multiple predator effects (MPE) studies generates biased predictions in applications of common experimental and quantitative frameworks. Here, we explore additional sources of bias stemming from nonlinearities in prey predation risk. We show that in order to avoid bias, predictions about the combined effects of independent predators must account for nonlinear size-dependent risk for prey as well as changes in prey risk driven by nonlinear predator functional responses and depletion. Historical failure to account for biases introduced by well-known nonlinear processes that affect predation risk suggest that we may need to reevaluate the general conclusions that have been drawn about the ubiquity of emergent MPEs over the past three decades.
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Affiliation(s)
- Michael W. McCoy
- Florida Atlantic University (Harbor Branch Campus), Ft. Pierce, FL, United States
| | - Elizabeth Hamman
- St. Mary’s College of Maryland, St Mary’s City, MD, United States
| | | | | | - James R. Vonesh
- Virginia Commonwealth University, Richmond, VA, United States
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7
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Guariento RD, Dalponti G, Carneiro LS, Caliman A. Prey defense phenotype mediates multiple-predator effects in tri-trophic food-webs. J Anim Ecol 2022; 91:2023-2036. [PMID: 35839141 DOI: 10.1111/1365-2656.13777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 07/06/2022] [Indexed: 11/28/2022]
Abstract
1. The emphasis on mechanisms governing the interaction among predators (e.g., cooperation, competition, or intraguild predation) has driven the understanding of multiple-predator effects on prey survival and dynamics. However, overwhelming evidence shows that prey can adaptively respond to predators, exhibiting multiple defensive phenotypes to cope with predation. Nevertheless, there is still a relatively scarce theory connecting the emergence of prey defenses in complex multi-predator scenarios and their ecological consequences. 2. Using a mathematical approach, we evaluated the prevalence of defended prey phenotypes as a function of predator-induced mortality in a two-predator system, and how prey and phenotype dynamics affect trophic cascades. We also evaluated such responses when prey manifests a general defense against both predators (i.e., risk-reducing) or a specialized defense against one predator at the expense of defense against the other predator (i.e., risk trade-off), and when such phenotypes induce fitness and foraging costs. 3. We showed that the emergence of defended phenotypes under multiple predators depends on predator-induced mortality rates, the magnitude of phenotype costs, and the effect of the defensive phenotype on the performance of all predators. 4. Risk-reducing phenotypes enhance prioritized responses to predators with high killing rates, but prioritized responses are diminished when prey manifest risk trade-off phenotypes. Finally, we showed that resource abundance across the predation gradient directly depends on the prevalence of certain prey phenotypes and their effect on foraging costs. 5. Ultimately, our results depict the implications of prey defenses on prey and basal resources abundance in a multiple predators' environment, highlighting the role of the identity of defensive strategies in mediating the strength and nature of trophic cascades, via consumptive or non-consumptive effects.
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Affiliation(s)
- Rafael Dettogni Guariento
- Laboratório de Ecologia, Instituto de Biociências, Universidade Federal do Mato Grosso do Sul, Campo Grande, 79070-900, MS, Brasil
| | - Guilherme Dalponti
- Laboratório de Ecologia, Instituto de Biociências, Universidade Federal do Mato Grosso do Sul, Campo Grande, 79070-900, MS, Brasil
| | - Luciana Silva Carneiro
- Departamento de Ecologia, Universidade Federal do Rio Grande do Norte, Natal, 59078-970, RN, Brasil
| | - Adriano Caliman
- Departamento de Ecologia, Universidade Federal do Rio Grande do Norte, Natal, 59078-970, RN, Brasil
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8
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Thierry M, Pardikes NA, Rosenbaum B, Ximénez-Embún MG, Hrček J. The presence of multiple parasitoids decreases host survival under warming, but parasitoid performance also decreases. Proc Biol Sci 2022; 289:20220121. [PMID: 35291840 PMCID: PMC8924747 DOI: 10.1098/rspb.2022.0121] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Current global changes are reshaping ecological communities and modifying environmental conditions. We need to recognize the combined impact of these biotic and abiotic factors on species interactions, community dynamics and ecosystem functioning. Specifically, the strength of predator-prey interactions often depends on the presence of other natural enemies: it weakens with competition and interference or strengthens with facilitation. Such effects of multiple predators on prey are likely to be affected by changes in the abiotic environment, altering top-down control, a key structuring force in natural and agricultural ecosystems. Here, we investigated how warming alters the effects of multiple predators on prey suppression using a dynamic model coupled with empirical laboratory experiments with Drosophila-parasitoid communities. While multiple parasitoids enhanced top-down control under warming, parasitoid performance generally declined when another parasitoid was present owing to competitive interactions. This could reduce top-down control over multiple generations. Our study highlights the importance of accounting for interactive effects between abiotic and biotic factors to better predict community dynamics in a rapidly changing world and thus better preserve ecosystem functioning and services such as biological control.
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Affiliation(s)
- Mélanie Thierry
- Faculty of Science, University of South Bohemia, Branisovska 31, 37005 Czech Republic,Biology Centre of the Czech Academy of Sciences, Institute of Entomology, Branisovska 31, 37005, Czech Republic
| | - Nicholas A. Pardikes
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, Branisovska 31, 37005, Czech Republic
| | - Benjamin Rosenbaum
- Theory in Biodiversity Science, German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Puschstr. 4, 04103 Leipzig, Germany,Institute of Biodiversity, Friedrich Schiller University Jena, Dornburger Str. 159, 07743 Jena, Germany
| | - Miguel G. Ximénez-Embún
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, Branisovska 31, 37005, Czech Republic
| | - Jan Hrček
- Faculty of Science, University of South Bohemia, Branisovska 31, 37005 Czech Republic,Biology Centre of the Czech Academy of Sciences, Institute of Entomology, Branisovska 31, 37005, Czech Republic
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9
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Juliano SA, Goughnour JA, Ower GD. Predation in Many Dimensions: Spatial Context Is Important for Meaningful Functional Response Experiments. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.845560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
For simplicity and to minimize variation, functional response experiments frequently use environments of simple physical structure and small size. Less attention is paid to similarity of the experimental environment to the natural environment where predation occurs. Assumptions about predator and prey use of space are often implied in the choice of experimental environment. We illustrate how these assumptions may affect conclusions with an experiment testing how arena size affects a functional response. Toxorhynchites rutilus preyed upon larval Culex restuans in containers differing in volume by 15x, but spanning a similar range of prey/liter. The most plausible Type II model included attack rates that were statistically indistinguishable, but in the larger volume, had handling time that was lower by > 30x compared to the smaller volume, suggesting a major change in predator behavior with container volume. When we altered our assumption that predation scales with prey/liter, assuming instead that aggregation causes predation to scale with prey/area of surface or bottom, the conclusions changed: neither attack rate nor handling time differed with container size. Thus, our assumption about how predator and prey used space altered the conclusions of the experiment. We then summarize recently published experiments showing that spatial context affects estimated functional responses. We suggest that functional response experiments would be improved by using larger experimental spaces that represent physical complexity of environments where predation occurs. Greater spatial extent and complexity are likely to cause aggregation of predation. Effects of more realistic spatial context are likely to yield more complete understanding of quantitative aspects of predation.
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10
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Multiple-Predator Effects and Functional Redundancy of Pond Predators. J HERPETOL 2022. [DOI: 10.1670/20-080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Functional Responses and Additive Multiple Predator Effects of Two Common Wetland Fish. WATER 2022. [DOI: 10.3390/w14050699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Understanding trophic interactions is essential for the prediction and measurement of structure and function in aquatic environments. Communities in these ecosystems may be shaped by variables such as predator diversity, prey density and emergent multiple predator effects (MPEs), which are likely to influence trophic dynamics. In this study, we examined the effect of key predatory fish in floodplain wetlands, namely Oreochromis mossambicus and Enteromius paludinosus, towards Chironomidae prey, using a comparative functional response (FR) approach. We used single predator species as well as intra- and interspecific paired species to contrast FRs under multiple predator scenarios. Attack rate and handling time estimates from single predator FRs were used to predict multiple predators’ feeding rates, which were compared to observe multiple predators’ feeding rates to quantify potential MPEs. From single fish trials, each species displayed a significant Type II FR, characterized by high feeding rates at low prey densities. Oreochromis mossambicus had a steeper (initial slope, i.e., higher attack rate) and higher (asymptote of curve, i.e., shorter handling time and higher maximum feeding rate) FR, whereas E. paludinosus exhibited lower-magnitude FRs (i.e., lower attack rate, longer handling time and lower feeding rate). In multiple predator scenarios, feeding rates were well-predicted by those of single predators, both in conspecific and interspecific pairs, and thus we did not find evidence for antagonistic or synergistic MPEs. Predator–prey interactions in wetland systems can have significant consequences on the structure and dynamics of ecological communities. In turn, this could have destabilizing effects on resources in tropical wetlands. These results, although experimental, help us understand how trophic interaction among conspecific or interspecific fish species in Austral tropical wetlands might influence their aquatic prey species. This will help us to understand food web dynamics better.
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Rakowski CJ, Farrior CE, Manning SR, Leibold MA. Predator complementarity dampens variability of phytoplankton biomass in a diversity-stability trophic cascade. Ecology 2021; 102:e03534. [PMID: 34496044 DOI: 10.1002/ecy.3534] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 06/15/2021] [Accepted: 07/08/2021] [Indexed: 11/11/2022]
Abstract
Trophic cascades - indirect effects of predators that propagate down through food webs - have been extensively documented in many ecosystem types. It has also been shown that predator diversity can mediate these trophic cascades and, separately, that herbivore biomass can influence the stability of primary producers. However, whether predator diversity can cause cascading effects on the stability of lower trophic levels has not yet been studied. We conducted a laboratory microcosm experiment and a field mesocosm experiment manipulating the presence and coexistence of two heteropteran predators and measuring their effects on zooplankton herbivores and phytoplankton basal resources. We predicted that if the predators partitioned their zooplankton prey, for example by size, then the co-presence of the predators would reduce zooplankton prey mass and lead to (1) increased biomass of, and (2) decreased temporal variability of phytoplankton basal resources. We present evidence that the predators partitioned their zooplankton prey, leading to a synergistic suppression of zooplankton. In turn, this enhanced zooplankton suppression led to only a weak, non-significant increase in the central tendency of phytoplankton biomass, but significantly reduced its variability. Our results demonstrate that predator diversity may indirectly stabilize basal resource biomass via a "diversity-stability trophic cascade," seemingly dependent on predator complementarity, even when there is no significant classic trophic cascade altering the central tendency of biomass. Therefore predator diversity, especially if correlated with diversity of prey use, could play a role in regulating ecosystem stability. This link between predator diversity and producer stability has implications for conservation and for potential biological control methods to improve crop yield reliability.
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Affiliation(s)
- Chase J Rakowski
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, 78712, USA
| | - Caroline E Farrior
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, 78712, USA
| | - Schonna R Manning
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, 78712, USA
| | - Mathew A Leibold
- Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
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13
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Resetarits WJ, Pintar MR, Bohenek JR. Complex multi‐predator effects on demographic habitat selection and community assembly in colonizing aquatic insects. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1474] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- William J. Resetarits
- Department of Biology Centers for Water and Wetlands Resources, and Conservation and Biodiversity Research The University of Mississippi University Mississippi 38677‐1848 USA
| | - Matthew R. Pintar
- Department of Biology Centers for Water and Wetlands Resources, and Conservation and Biodiversity Research The University of Mississippi University Mississippi 38677‐1848 USA
| | - Jason R. Bohenek
- Department of Biology Centers for Water and Wetlands Resources, and Conservation and Biodiversity Research The University of Mississippi University Mississippi 38677‐1848 USA
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14
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Cuthbert RN, Dalu T, Wasserman RJ, Sentis A, Weyl OLF, Froneman PW, Callaghan A, Dick JTA. Prey and predator density-dependent interactions under different water volumes. Ecol Evol 2021; 11:6504-6512. [PMID: 34141235 PMCID: PMC8207356 DOI: 10.1002/ece3.7503] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 01/28/2023] Open
Abstract
Predation is a critical ecological process that directly and indirectly mediates population stabilities, as well as ecosystem structure and function. The strength of interactions between predators and prey may be mediated by multiple density dependences concerning numbers of predators and prey. In temporary wetland ecosystems in particular, fluctuating water volumes may alter predation rates through differing search space and prey encounter rates. Using a functional response approach, we examined the influence of predator and prey densities on interaction strengths of the temporary pond specialist copepod Lovenula raynerae preying on cladoceran prey, Daphnia pulex, under contrasting water volumes. Further, using a population dynamic modeling approach, we quantified multiple predator effects across differences in prey density and water volume. Predators exhibited type II functional responses under both water volumes, with significant antagonistic multiple predator effects (i.e., antagonisms) exhibited overall. The strengths of antagonistic interactions were, however, enhanced under reduced water volumes and at intermediate prey densities. These findings indicate important biotic and abiotic contexts that mediate predator-prey dynamics, whereby multiple predator effects are contingent on both prey density and search area characteristics. In particular, reduced search areas (i.e., water volumes) under intermediate prey densities could enhance antagonisms by heightening predator-predator interference effects.
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Affiliation(s)
- Ross N. Cuthbert
- GEOMAR Helmholtz‐Zentrum für Ozeanforschung KielKielGermany
- Institute for Global Food Security, School of Biological SciencesQueen's University BelfastBelfastUK
- South African Institute for Aquatic BiodiversityMakhandaSouth Africa
| | - Tatenda Dalu
- South African Institute for Aquatic BiodiversityMakhandaSouth Africa
- School of Biology and Environmental SciencesUniversity of MpumalangaNelspruitSouth Africa
| | - Ryan J. Wasserman
- South African Institute for Aquatic BiodiversityMakhandaSouth Africa
- Department of Zoology and EntomologyRhodes UniversityMakhandaSouth Africa
| | - Arnaud Sentis
- INRAEAix Marseille University, UMR RECOVERAix‐en‐ProvenceFrance
| | - Olaf L. F. Weyl
- DSI/NRF Research Chair in Inland Fisheries and Freshwater EcologySouth African Institute for Aquatic BiodiversityMakhandaSouth Africa
| | | | - Amanda Callaghan
- Ecology and Evolutionary Biology, School of Biological SciencesUniversity of ReadingReadingUK
| | - Jaimie T. A. Dick
- Institute for Global Food Security, School of Biological SciencesQueen's University BelfastBelfastUK
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15
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Resetarits WJ, Bohenek JR, Pintar MR. Predator-specific responses and emergent multi-predator effects on oviposition site choice in grey treefrogs, Hyla chrysoscelis. Proc Biol Sci 2021; 288:20210558. [PMID: 33975473 PMCID: PMC8113890 DOI: 10.1098/rspb.2021.0558] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/19/2021] [Indexed: 11/12/2022] Open
Abstract
Predators affect prey through both consumptive and non-consumptive effects (NCEs), and prey typically face threats from multiple simultaneous predators. While different predators have a variety of NCEs on prey, little is known regarding effects of simultaneous multiple predators on demographic habitat selection. Demographic habitat selection is unique among NCEs, especially in discrete habitat patches; decisions directly affect both distribution and abundance of species across habitat patches, rather than simply abundance and performance within patches. Our goal was to determine strength of avoidance responses to multiple species/species combinations of predatory fish, and responses to predator richness. We assessed responses of ovipositing grey treefrogs (Hyla chrysoscelis) to three predatory fish species and substitutive combination of species. In single-species treatments, treefrogs avoided only one species, Notemigonus crysoleucas. All two-species combinations, and the three-species combination, were avoided, including the Fundulus chrysotus × Noturus phaeus combination, of which neither were avoided alone. This suggests emergent properties of multiple predators, with potential interactive effects among cues themselves or in the perception of cues by treefrogs. Our results indicate effects of multiple predators are not predictable based on individual effects, and illustrate the importance and complexity of effects of demographic habitat selection on distribution and abundance.
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Affiliation(s)
- William J. Resetarits
- Department of Biology and Centers for Water and Wetlands Resources, and Biodiversity and Conservation Research, The University of Mississippi, University, MS 38677-1848, USA
| | - Jason R. Bohenek
- Department of Biology and Centers for Water and Wetlands Resources, and Biodiversity and Conservation Research, The University of Mississippi, University, MS 38677-1848, USA
| | - Matthew R. Pintar
- Department of Biology and Centers for Water and Wetlands Resources, and Biodiversity and Conservation Research, The University of Mississippi, University, MS 38677-1848, USA
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16
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Neale JT, Juliano SA. Predation yields greater population performance: What are the contributions of density- and trait-mediated effects? ECOLOGICAL ENTOMOLOGY 2021; 46:56-65. [PMID: 34092899 PMCID: PMC8171192 DOI: 10.1111/een.12940] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
1. Population responses to extrinsic mortality can yield no change in number of survivors (compensation) or an increase in number of survivors (overcompensation) when the population is regulated by negative density-dependence. This intriguing response has been the subject of theoretical studies, but few experiments have explored how the source of extrinsic mortality affects the response. 2. This study tests abilities of three functionally diverse predators, alone and combined, to induce (over)compensation of a prey population. Larval Aedes aegypti (Diptera: Culicidae) were exposed to predation by Mesocyclops longisetus (Crustacea: Copepoda), Anopheles barberi (Diptera: Culicidae), Corethrella appendiculata (Diptera: Corethrellidae), all three in a substitutive design, or no predation. 3. The number of survivors to adulthood, female size and development time, and a composite index of performance (r') were analysed. Predator treatment did not have a significant effect on total number of survivors, nor on number of males, suggesting mortality by predation was compensatory. Predation significantly affected number of female survivors, with a trend of more females produced with predation, though no post hoc tests were significant. Predation significantly increased female development rate and r' relative to no-predator control. 4. A sensitivity analysis indicated that the change in the number of female adults produced was the largest contributing factor to the differences in r' among cohorts. While predation did not significantly increase overall production of adults, it did release survivors from density-dependent effects sufficiently to increase population performance. This study provides an empirical test of mechanisms by which predation may yield positive effects on a population of victims, a phenomenon predicted to occur across many taxa and food webs.
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17
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Novak M, Stouffer DB. Systematic bias in studies of consumer functional responses. Ecol Lett 2021; 24:580-593. [PMID: 33381898 DOI: 10.1111/ele.13660] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/09/2020] [Accepted: 11/18/2020] [Indexed: 12/31/2022]
Abstract
Functional responses are a cornerstone to our understanding of consumer-resource interactions, so how to best describe them using models has been actively debated. Here we focus on the consumer dependence of functional responses to evidence systematic bias in the statistical comparison of functional-response models and the estimation of their parameters. Both forms of bias are universal to nonlinear models (irrespective of consumer dependence) and are rooted in a lack of sufficient replication. Using a large compilation of published datasets, we show that - due to the prevalence of low sample size studies - neither the overall frequency by which alternative models achieve top rank nor the frequency distribution of parameter point estimates should be treated as providing insight into the general form or central tendency of consumer interference. We call for renewed clarity in the varied purposes that motivate the study of functional responses, purposes that can compete with each other in dictating the design, analysis and interpretation of functional-response experiments.
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Affiliation(s)
- Mark Novak
- Department of Integrative Biology, Oregon State University, Corvallis, OR, 97331, USA
| | - Daniel B Stouffer
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, 8140, New Zealand
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18
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Abstract
Predation is ubiquitous in nature and can be an important component of both ecological and evolutionary interactions. One of the most striking features of predators is how often they cause evolutionary diversification in natural systems. Here, we review several ways that this can occur, exploring empirical evidence and suggesting promising areas for future work. We also introduce several papers recently accepted in Diversity that demonstrate just how important and varied predation can be as an agent of natural selection. We conclude that there is still much to be done in this field, especially in areas where multiple predator species prey upon common prey, in certain taxonomic groups where we still know very little, and in an overall effort to actually quantify mortality rates and the strength of natural selection in the wild.
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19
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Buxton M, Cuthbert RN, Dalu T, Nyamukondiwa C, Wasserman RJ. Predator density modifies mosquito regulation in increasingly complex environments. PEST MANAGEMENT SCIENCE 2020; 76:2079-2086. [PMID: 31943746 DOI: 10.1002/ps.5746] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 12/16/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND Predation plays a pivotal role in the composition and functioning of ecosystems. Both habitat complexity and predator density are important contexts which may determine the strength of trophic and non-trophic interactions. In aquatic systems, the efficacy of natural enemies in regulating vector pest species could be modified by such context dependencies. Here, we use a functional response (FR) approach to experimentally quantify conspecific multiple predator effects across a habitat complexity gradient of two notonectids, Anisops sardea and Enithares chinai, towards larvae of the vector mosquito Culex pipiens pipiens. RESULTS E. chinai exhibited significantly greater consumption rates than A. sardea across habitat complexities, both as individuals and conspecific pairs. Each predator type displayed Type II FRs across experimental treatments, with synergistic multiple predator effects (i.e. prey risk enhancement) displayed in the absence of habitat complexity. Effects of increasing habitat complexity modified multiple predator effects differentially between species given behavioral differences, with habitat complexity causing significant antagonism (i.e. prey risk reduction) with multiple A. sardea compared to E. chinai. CONCLUSION Habitat complexity effects on multiple predator interactions can manifest differently at the species level, suggesting emergent effects which complicate predictions of natural enemy impact in heterogenous environments. Considerations of density, diversity and habitat effects on efficacies of natural enemies should thus be considered by pest management practitioners to better explain biocontrol efficacies in increasingly diverse environments. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Mmabaledi Buxton
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
| | - Ross N Cuthbert
- School of Biological Sciences, Queen's University Belfast, Belfast, UK
| | - Tatenda Dalu
- Department of Ecology and Resource Management, University of Venda, Thohoyandou, South Africa
| | - Casper Nyamukondiwa
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
| | - Ryan J Wasserman
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
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20
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21
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Hopkins SR, Fleming‐Davies AE, Belden LK, Wojdak JM. Systematic review of modelling assumptions and empirical evidence: Does parasite transmission increase nonlinearly with host density? Methods Ecol Evol 2020. [DOI: 10.1111/2041-210x.13361] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
| | - Arietta E. Fleming‐Davies
- Biology Department University of San Diego San Diego CA USA
- Department of Biology Radford University Radford VA USA
| | - Lisa K. Belden
- Department of Biological Sciences Virginia Tech Blacksburg VA USA
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22
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Ellis KS, Larsen RT, Koons DN. The importance of functional responses among competing predators for avian nesting success. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13460] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Kristen S. Ellis
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins CO USA
| | - Randy T. Larsen
- Department of Plant and Wildlife Sciences Brigham Young University Provo UT USA
| | - David N. Koons
- Department of Fish, Wildlife, and Conservation Biology Graduate Degree Program in Ecology Colorado State University Fort Collins CO USA
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23
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Rendon D, Taylor PW, Whitehouse MEA. Multiple intraguild predators reduce mortality risk of a mutual agricultural pest prey in simple, but not in complex, experimental settings. AUSTRAL ECOL 2019. [DOI: 10.1111/aec.12773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dalila Rendon
- CSIRO Agriculture and Food; Australian Cotton Research Institute; 21888 Kamilaroi Hwy Narrabri New South Wales 2390 Australia
- Department of Biological Sciences; Macquarie University; Sydney New South Wales Australia
| | - Phillip W. Taylor
- Department of Biological Sciences; Macquarie University; Sydney New South Wales Australia
| | - Mary E. A. Whitehouse
- CSIRO Agriculture and Food; Australian Cotton Research Institute; 21888 Kamilaroi Hwy Narrabri New South Wales 2390 Australia
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24
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Kohl MT, Ruth TK, Metz MC, Stahler DR, Smith DW, White PJ, MacNulty DR. Do prey select for vacant hunting domains to minimize a multi-predator threat? Ecol Lett 2019; 22:1724-1733. [PMID: 31373137 DOI: 10.1111/ele.13319] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 02/13/2019] [Accepted: 05/09/2019] [Indexed: 01/02/2023]
Abstract
Many ecosystems contain sympatric predator species that hunt in different places and times. We tested whether this provides vacant hunting domains, places and times where and when predators are least active, that prey use to minimize threats from multiple predators simultaneously. We measured how northern Yellowstone elk (Cervus elaphus) responded to wolves (Canis lupus) and cougars (Puma concolor), and found that elk selected for areas outside the high-risk domains of both predators consistent with the vacant domain hypothesis. This enabled elk to avoid one predator without necessarily increasing its exposure to the other. Our results demonstrate how the diel cycle can serve as a key axis of the predator hunting domain that prey exploit to manage predation risk from multiple sources. We argue that a multi-predator, spatiotemporal framework is vital to understand the causes and consequences of prey spatial response to predation risk in environments with more than one predator.
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Affiliation(s)
- Michel T Kohl
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Toni K Ruth
- Hornocker Wildlife Institute/Wildlife Conservation Society, Bozeman, MT, 59715, USA.,Salmon Valley Stewardship, Salmon, ID, 83467, USA
| | - Matthew C Metz
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, WY, 82190, USA.,Wildlife Biology Program, University of Montana, Missoula, MT, 59812, USA
| | - Daniel R Stahler
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, WY, 82190, USA
| | - Douglas W Smith
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, WY, 82190, USA
| | - P J White
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, WY, 82190, USA
| | - Daniel R MacNulty
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, UT, 84322, USA
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25
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Yuan X, Zhou WW, Jiang YD, Yu H, Wu SY, Gao YL, Cheng JA, Zhu ZR. Organic Regime Promotes Evenness of Natural Enemies and Planthopper Control in Paddy Fields. ENVIRONMENTAL ENTOMOLOGY 2019; 48:318-325. [PMID: 30799492 DOI: 10.1093/ee/nvz013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Indexed: 06/09/2023]
Abstract
Planthoppers (Nilaparvata lugens, Sogatella furcifera, and Laodelphax striatellus) (Hemiptera: Delphacidae) are the most important pests affecting rice production. Pesticide spraying for its control may cause harmful effects on human health and the environment, especially the loss of biodiversity. The consequences of these changes on biodiversity and ecological services are well studied in tropical irrigated paddy fields, but are largely unknown in subtropical areas. Organic regime provides an environment-friendly method for biodiversity conservation; however, it is unclear whether this regime can suppress planthopper populations effectively in paddy fields. Consequently, we compared species richness, abundance, community structure, and evenness of natural enemies and planthoppers between organic and conventional rice fields (n = 35) distributed across four sites in China. The results showed that species richness was higher in organic fields than in conventional fields. Shannon index and evenness of predators and parasitoids were higher in most of the organic fields than their conventional counterparts. Furthermore, planthopper density showed a significant negative relationship with increased richness and evenness for both predators and parasitoids. These results underscore the notion that management regimes influence biodiversity in rice field. Most importantly, this has direct implications on the efficacy of natural pest control services rendered by predators and parasitoids associated with planthoppers in China and potentially other rice production regions in Asia.
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Affiliation(s)
- Xin Yuan
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
- Agricultural Experimental Station, Zhejiang University, Hangzhou, China
| | - Wen-Wu Zhou
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
| | - Yan-Dong Jiang
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
| | - Hang Yu
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
| | - Sheng-Yong Wu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Yu-Lin Gao
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Jia-An Cheng
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
| | - Zeng-Rong Zhu
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
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26
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On the use of functional responses to quantify emergent multiple predator effects. Sci Rep 2018; 8:11787. [PMID: 30082837 PMCID: PMC6079024 DOI: 10.1038/s41598-018-30244-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 06/20/2018] [Indexed: 11/20/2022] Open
Abstract
Non-independent interactions among predators can have important consequences for the structure and dynamics of ecological communities by enhancing or reducing prey mortality rate through, e.g., predator facilitation or interference. The multiplicative risk model, traditionally used to detect these emergent multiple predator effects (MPEs), is biased because it assumes linear functional response (FR) and no prey depletion. To rectify these biases, two approaches based on FR modelling have recently been proposed: the direct FR approach and the population-dynamic approach. Here we compare the strengths, limitations and predictions of the three approaches using simulated data sets. We found that the predictions of the direct FR and the multiplicative risk models are very similar and underestimate predation rates when prey density is high or prey depletion is substantial. As a consequence, these two approaches often fail in detecting risk reduction. Finally, parameters estimated with the direct FR approach lack mechanistic interpretation, which limits the understanding of the mechanisms driving multiple predator interactions and potential extension of this approach to more complex food webs. We thus strongly recommend using the population-dynamic approach because it is robust, precise, and provides a scalable mechanistic framework to detect and quantify MPEs.
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27
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Palacios MM, Malerba ME, McCormick MI. Multiple predator effects on juvenile prey survival. Oecologia 2018; 188:417-427. [DOI: 10.1007/s00442-018-4182-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 06/02/2018] [Indexed: 11/30/2022]
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28
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Michaelides G, Sfenthourakis S, Pitsillou M, Seraphides N. Functional response and multiple predator effects of two generalist predators preying on Tuta absoluta eggs. PEST MANAGEMENT SCIENCE 2018; 74:332-339. [PMID: 28815991 DOI: 10.1002/ps.4703] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/17/2017] [Accepted: 08/11/2017] [Indexed: 06/07/2023]
Abstract
BACKROUND Interactions among invertebrate predators could affect a pest suppression. The hemipteran species Macrolophus pygmaeus (Rambur) and Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) are natural enemies of several pests in agroecosystems and coexist in tomato crops in Mediterranean countries. By using the multiplicative risk model (MRM) and the substitutive model, the multiple predator effects (MPEs) on prey suppression were calculated when two individuals of the predators foraged at the same densities on South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), eggs. RESULTS Egg consumption increased with increasing egg density and the two predators exhibited a type III functional response. Predation rates were strongly affected by prey density. Using the MRM, we found risk reduction at intraspecific treatments at high prey density. Applying the substitutive model, we detect risk enhancement at interspecific treatments at high egg density. CONCLUSIONS At low prey densities, most of the interactions were independent, whereas at high densities most interactions were not independent and resulted in prey risk reduction, indicating antagonism between the individuals involved. We also showed that N. tenuis is a more competitive predator species for T. absoluta eggs than M. pygmaeus; however, combination of the two predator species will lead to better pest suppression at high T. absoluta population densities. © 2017 Society of Chemical Industry.
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Affiliation(s)
| | | | - Maria Pitsillou
- Department of Mathematics and Statistics, University of Cyprus, Nicosia, Cyprus
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29
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Keystone mutualism strengthens top–down effects by recruiting large-bodied ants. Oecologia 2018; 186:601-610. [DOI: 10.1007/s00442-017-4047-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/12/2017] [Indexed: 10/18/2022]
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30
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Effects of prey density, temperature and predator diversity on nonconsumptive predator-driven mortality in a freshwater food web. Sci Rep 2017; 7:18075. [PMID: 29273716 PMCID: PMC5741715 DOI: 10.1038/s41598-017-17998-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 12/05/2017] [Indexed: 11/08/2022] Open
Abstract
Nonconsumptive predator-driven mortality (NCM), defined as prey mortality due to predation that does not result in prey consumption, is an underestimated component of predator-prey interactions with possible implications for population dynamics and ecosystem functioning. However, the biotic and abiotic factors influencing this mortality component remain largely unexplored, leaving a gap in our understanding of the impacts of environmental change on ecological communities. We investigated the effects of temperature, prey density, and predator diversity and density on NCM in an aquatic food web module composed of dragonfly larvae (Aeshna cyanea) and marbled crayfish (Procambarus fallax f. virginalis) preying on common carp (Cyprinus carpio) fry. We found that NCM increased with prey density and depended on the functional diversity and density of the predator community. Warming significantly reduced NCM only in the dragonfly larvae but the magnitude depended on dragonfly larvae density. Our results indicate that energy transfer across trophic levels is more efficient due to lower NCM in functionally diverse predator communities, at lower resource densities and at higher temperatures. This suggests that environmental changes such as climate warming and reduced resource availability could increase the efficiency of energy transfer in food webs only if functionally diverse predator communities are conserved.
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31
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Beppler C, Tekin E, Mao Z, White C, McDiarmid C, Vargas E, Miller JH, Savage VM, Yeh PJ. Uncovering emergent interactions in three-way combinations of stressors. J R Soc Interface 2017; 13:rsif.2016.0800. [PMID: 27974577 DOI: 10.1098/rsif.2016.0800] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/23/2016] [Indexed: 11/12/2022] Open
Abstract
Understanding how multiple stressors interact is needed to predict the dynamical outcomes of diverse biological systems, ranging from drug-resistant pathogens that are combated and treated with combination drug therapies to ecosystems impacted by environmental toxicants or disturbances. Nevertheless, extensive studies of higher-order (more than two component) interactions have been lacking. Here, we conduct experiments using 20 three-drug combinations and their effects on the bacterial growth of Escherichia coli We report our measurements of growth rates in single, pairwise and triple-drug combinations. To uncover emergent interactions, we derive a simple framework to calculate expectations for three-way interactions based on the measured impact of each individual stressor and of each pairwise interaction. Using our framework, we find that (i) emergent antagonisms are more common than emergent synergies and (ii) emergent antagonisms are more common and emergent synergies are more rare than would be inferred from measures of net effects that do not disentangle pairwise interactions from three-way interactions.
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Affiliation(s)
- Casey Beppler
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA.,Department of Microbiology, Immunology, and Molecular Genetics, The Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
| | - Elif Tekin
- Department of Biomathematics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Zhiyuan Mao
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA.,Department of Microbiology, Immunology, and Molecular Genetics, The Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
| | - Cynthia White
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA
| | - Cassandra McDiarmid
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA
| | - Emily Vargas
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA
| | - Jeffrey H Miller
- Department of Microbiology, Immunology, and Molecular Genetics, The Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
| | - Van M Savage
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA.,Department of Biomathematics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA.,Santa Fe Institute, Santa Fe, NM 87501, USA
| | - Pamela J Yeh
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA
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32
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Terry JCD, Morris RJ, Bonsall MB. Trophic interaction modifications: an empirical and theoretical framework. Ecol Lett 2017; 20:1219-1230. [PMID: 28921859 PMCID: PMC6849598 DOI: 10.1111/ele.12824] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/01/2017] [Accepted: 07/17/2017] [Indexed: 12/01/2022]
Abstract
Consumer-resource interactions are often influenced by other species in the community. At present these 'trophic interaction modifications' are rarely included in ecological models despite demonstrations that they can drive system dynamics. Here, we advocate and extend an approach that has the potential to unite and represent this key group of non-trophic interactions by emphasising the change to trophic interactions induced by modifying species. We highlight the opportunities this approach brings in comparison to frameworks that coerce trophic interaction modifications into pairwise relationships. To establish common frames of reference and explore the value of the approach, we set out a range of metrics for the 'strength' of an interaction modification which incorporate increasing levels of contextual information about the system. Through demonstrations in three-species model systems, we establish that these metrics capture complimentary aspects of interaction modifications. We show how the approach can be used in a range of empirical contexts; we identify as specific gaps in current understanding experiments with multiple levels of modifier species and the distributions of modifications in networks. The trophic interaction modification approach we propose can motivate and unite empirical and theoretical studies of system dynamics, providing a route to confront ecological complexity.
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Affiliation(s)
| | - Rebecca J. Morris
- Department of ZoologyUniversity of OxfordOxfordOX1 3PSUK
- Biological Sciences, Faculty of Natural and Environmental SciencesUniversity of SouthamptonLife Sciences Building 85Highfield CampusSouthamptonSO17 1BJUK
| | - Michael B. Bonsall
- Department of ZoologyUniversity of OxfordOxfordOX1 3PSUK
- St. Peter's CollegeNew Inn Hall StreetOxfordOX1 2DLUK
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33
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Allen BL, Allen LR, Andrén H, Ballard G, Boitani L, Engeman RM, Fleming PJ, Ford AT, Haswell PM, Kowalczyk R, Linnell JD, David Mech L, Parker DM. Can we save large carnivores without losing large carnivore science? FOOD WEBS 2017. [DOI: 10.1016/j.fooweb.2017.02.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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34
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Sentis A, Gémard C, Jaugeon B, Boukal DS. Predator diversity and environmental change modify the strengths of trophic and nontrophic interactions. GLOBAL CHANGE BIOLOGY 2017; 23:2629-2640. [PMID: 27862723 DOI: 10.1111/gcb.13560] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 10/25/2016] [Indexed: 06/06/2023]
Abstract
Understanding the dependence of species interaction strengths on environmental factors and species diversity is crucial to predict community dynamics and persistence in a rapidly changing world. Nontrophic (e.g. predator interference) and trophic components together determine species interaction strengths, but the effects of environmental factors on these two components remain largely unknown. This impedes our ability to fully understand the links between environmental drivers and species interactions. Here, we used a dynamical modelling framework based on measured predator functional responses to investigate the effects of predator diversity, prey density, and temperature on trophic and nontrophic interaction strengths within a freshwater food web. We found that (i) species interaction strengths cannot be predicted from trophic interactions alone, (ii) nontrophic interaction strengths vary strongly among predator assemblages, (iii) temperature has opposite effects on trophic and nontrophic interaction strengths, and (iv) trophic interaction strengths decrease with prey density, whereas the dependence of nontrophic interaction strengths on prey density is concave up. Interestingly, the qualitative impacts of temperature and prey density on the strengths of trophic and nontrophic interactions were independent of predator identity, suggesting a general pattern. Our results indicate that taking multiple environmental factors and the nonlinearity of density-dependent species interactions into account is an important step towards a better understanding of the effects of environmental variations on complex ecological communities. The functional response approach used in this study opens new avenues for (i) the quantification of the relative importance of the trophic and nontrophic components in species interactions and (ii) a better understanding how environmental factors affect these interactions and the dynamics of ecological communities.
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Affiliation(s)
- Arnaud Sentis
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
- Laboratory of Aquatic Insects and Relict Ecosystems, Biology Centre CAS, Institute of Entomology, 370 05, České Budějovice, Czech Republic
- Unité Mixte de Recherche 5174 'Evolution et Diversité Biologique', Centre National de la Recherche Scientifique, Université de Toulouse, Institut de Recherche pour le Développement, École Nationale de Formation Agronomique, BP 22687, 31326, Castanet-Tolosan, France
| | - Charlène Gémard
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Baptiste Jaugeon
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - David S Boukal
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
- Laboratory of Aquatic Insects and Relict Ecosystems, Biology Centre CAS, Institute of Entomology, 370 05, České Budějovice, Czech Republic
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Ganjisaffar F, Nachman G, Perring TM. Mutual interference between adult females of Galendromus flumenis (Acari: Phytoseiidae) feeding on eggs of Banks grass mite decreases predation efficiency and increases emigration rate. EXPERIMENTAL & APPLIED ACAROLOGY 2017; 72:1-14. [PMID: 28526953 DOI: 10.1007/s10493-017-0138-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 05/11/2017] [Indexed: 06/07/2023]
Abstract
The Banks grass mite, Oligonychus pratensis (Banks) (Acari: Tetranychidae) causes significant damage to dates in California (USA), if not controlled. Studies are underway to develop biological control strategies against this pest in dates using the predatory mite Galendromus flumenis (Chant) (Acari: Phytoseiidae). In California date gardens, this predator is found in low numbers that are insufficient for the economic suppression of Banks grass mites, and our research aims to understand why it fails to keep up with prey densities. The hypothesis that prey density and predator interference interactively determine the predation efficiency of G. flumenis was tested. In addition, the effect of arena size and prey and predator density manipulations on the emigration rate of the predator was investigated. Our results indicate that the per capita predation rate of G. flumenis decreases steeply with increasing predator density due to mutual interference. Analysis of emigration data considering the arena size and predator numbers showed that the emigration rate of G. flumenis was higher from small arenas, and increased with increasing predator numbers. When emigration data were analyzed using prey and predator densities as independent variables, only the effect of predator density was significant, suggesting that higher predator density increases the emigration rate of G. flumenis. These results contribute to our understanding of the predator-prey interactions, and help in designing strategies for more efficient augmentative releases of G. flumenis.
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Affiliation(s)
- Fatemeh Ganjisaffar
- Department of Entomology, University of California, 900 University Ave, Riverside, CA, 92521, USA.
| | - Gösta Nachman
- Section of Ecology and Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
| | - Thomas M Perring
- Department of Entomology, University of California, 900 University Ave, Riverside, CA, 92521, USA
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Shuman RM, Cherry MJ, Simoneaux TN, Dutoit EA, Kilgo JC, Chamberlain MJ, Miller KV. Survival of white-tailed deer neonates in Louisiana. J Wildl Manage 2017. [DOI: 10.1002/jwmg.21257] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rebecca M. Shuman
- Daniel B. Warnell School of Forestry and Natural Resources; University of Georgia; Athens GA 30602 USA
| | - Michael J. Cherry
- Department of Fish and Wildlife Conservation; Virginia Polytechnic Institute and State University; Blacksburg VA 24061 USA
| | - Taylor N. Simoneaux
- Daniel B. Warnell School of Forestry and Natural Resources; University of Georgia; Athens GA 30602 USA
| | - Elizabeth A. Dutoit
- Daniel B. Warnell School of Forestry and Natural Resources; University of Georgia; Athens GA 30602 USA
| | - John C. Kilgo
- USDA Forest Service; Southern Research Station; P.O Box 700 New Ellenton SC 29809 USA
| | - Michael J. Chamberlain
- Daniel B. Warnell School of Forestry and Natural Resources; University of Georgia; Athens GA 30602 USA
| | - Karl V. Miller
- Daniel B. Warnell School of Forestry and Natural Resources; University of Georgia; Athens GA 30602 USA
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Jonsson M, Kaartinen R, Straub CS. Relationships between natural enemy diversity and biological control. CURRENT OPINION IN INSECT SCIENCE 2017; 20:1-6. [PMID: 28602230 DOI: 10.1016/j.cois.2017.01.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 01/03/2017] [Indexed: 05/17/2023]
Abstract
Natural enemy diversity generally strengthens biological control, but individual studies have found everything from positive to negative effects. We discuss the factors that promote these different outcomes. We argue that a trait-based approach is helpful to improve our understanding of the relationship between enemy diversity and biological control, and suggest that enemy diversity is likely to be particularly important as an insurance against effects of climate change. Future research should increase the scale and ecological realism of enemy diversity studies, and consider both the strength and stability of biological control. Such research is likely to reveal even stronger evidence that conserving enemy biodiversity will improve biological pest control.
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Affiliation(s)
- Mattias Jonsson
- Swedish University of Agricultural Sciences, Department of Ecology, PO Box 7044, SE-750 07 Uppsala, Sweden.
| | - Riikka Kaartinen
- University of Edinburgh, Institute of Evolutionary Biology, Ashworth 11 Laboratories, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK.
| | - Cory S Straub
- Department of Biology, Ursinus College, Collegeville, PA 19426-1000, USA.
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Hodapp D, Hillebrand H. Effect of consumer loss on resource removal depends on species-specific traits. Ecosphere 2017. [DOI: 10.1002/ecs2.1742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Dorothee Hodapp
- Institute for Chemistry and Biology of the Marine Environment (ICBM); University of Oldenburg; Schleusenstr. 1 26382 Wilhelmshaven Germany
| | - Helmut Hillebrand
- Institute for Chemistry and Biology of the Marine Environment (ICBM); University of Oldenburg; Schleusenstr. 1 26382 Wilhelmshaven Germany
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Johnson I, Brinkman T, Lake B, Brown C. Winter hunting behavior and habitat selection of wolves in a low-density prey system. WILDLIFE BIOLOGY 2017. [DOI: 10.2981/wlb.00290] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Ian Johnson
- I. Johnson , PO Box 750881, Fairbanks, AK 99775, USA
| | - Todd Brinkman
- T. Brinkman, PO Box 757000, Fairbanks, AK 99775, USA
| | - Bryce Lake
- B. Lake, 101 12th Ave, Fairbanks, AK 99701, USA
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Rall BC, Latz E. Analyzing pathogen suppressiveness in bioassays with natural soils using integrative maximum likelihood methods in R. PeerJ 2016; 4:e2615. [PMID: 27833800 PMCID: PMC5101589 DOI: 10.7717/peerj.2615] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/25/2016] [Indexed: 11/20/2022] Open
Abstract
The potential of soils to naturally suppress inherent plant pathogens is an important ecosystem function. Usually, pathogen infection assays are used for estimating the suppressive potential of soils. In natural soils, however, co-occurring pathogens might simultaneously infect plants complicating the estimation of a focal pathogen's infection rate (initial slope of the infection-curve) as a measure of soil suppressiveness. Here, we present a method in R correcting for these unwanted effects by developing a two pathogen mono-molecular infection model. We fit the two pathogen mono-molecular infection model to data by using an integrative approach combining a numerical simulation of the model with an iterative maximum likelihood fit. We show that in presence of co-occurring pathogens using uncorrected data leads to a critical under- or overestimation of soil suppressiveness measures. In contrast, our new approach enables to precisely estimate soil suppressiveness measures such as plant infection rate and plant resistance time. Our method allows a correction of measured infection parameters that is necessary in case different pathogens are present. Moreover, our model can be (1) adapted to use other models such as the logistic or the Gompertz model; and (2) it could be extended by a facilitation parameter if infections in plants increase the susceptibility to new infections. We propose our method to be particularly useful for exploring soil suppressiveness of natural soils from different sites (e.g., in biodiversity experiments).
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Affiliation(s)
- Björn C Rall
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Institute of Ecology, Friedrich-Schiller University Jena, Jena, Germany; Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands; Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Ellen Latz
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Institute of Ecology, Friedrich-Schiller University Jena, Jena, Germany; Department of Animal Ecology, J.F. Blumenbach Institute of Zoology and Anthropology, Georg-August-University Göttingen, Göttingen, Germany
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Bao-Fundora L, Ramirez-Romero R, Sánchez-Hernández CV, Sánchez-Martínez J, Desneux N. Intraguild predation of Geocoris punctipes on Eretmocerus eremicus and its influence on the control of the whitefly Trialeurodes vaporariorum. PEST MANAGEMENT SCIENCE 2016; 72:1110-1116. [PMID: 26435031 DOI: 10.1002/ps.4163] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 06/05/2023]
Abstract
BACKGROUND Geocoris punctipes (Hemiptera: Lygaeidae) and Eretmocerus eremicus (Hymenoptera: Aphelinidae) are whitefly natural enemies. Previously, under laboratory conditions, we showed that G. punctipes engages in intraguild predation (IGP), the attack of one natural enemy by another, on E. eremicus. However, it is unknown whether this IGP interaction takes place under more complex scenarios, such as semi-field conditions. Even more importantly, the effect of this interaction on the density of the prey population requires investigation. Therefore, the present study aimed to establish whether this IGP takes place under semi-field conditions and to determine whether the predation rate of G. punctipes on the whitefly decreases when IGP takes place. RESULTS Molecular analysis showed that, under semi-field conditions, G. punctipes performed IGP on E. eremicus. However, although IGP did take place, the predation rate by G. punctipes on the whitefly was nevertheless higher when both natural enemies were present together than when the predator was present alone. CONCLUSION While IGP of G. punctipes on E. eremicus does occur under semi-field conditions, it does not adversely affect whitefly control. The concomitant use of these two natural enemies seems a valid option for inundative biological control programmes of T. vaporariorum in tomato. © 2015 Society of Chemical Industry.
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Affiliation(s)
- Lourdes Bao-Fundora
- Departamento de Producción Agrícola, CUCBA, Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | - Ricardo Ramirez-Romero
- Departamento de Producción Agrícola, CUCBA, Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | | | - José Sánchez-Martínez
- Departamento de Producción Agrícola, CUCBA, Universidad de Guadalajara, Zapopan, Jalisco, Mexico
| | - Nicolas Desneux
- French National Institute for Agricultural Research (INRA), Univ. Nice Sophia Antipolis, Institut Sophia Agrobiotech, Sophia-Antipolis, France
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Landová E, Musilová V, Polák J, Sedláčková K, Frynta D. Antipredatory reaction of the leopard gecko Eublepharis macularius to snake predators. Curr Zool 2016; 62:439-450. [PMID: 29491933 PMCID: PMC5804257 DOI: 10.1093/cz/zow050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 12/18/2015] [Indexed: 11/14/2022] Open
Abstract
Ability to recognize a risk of predation and react with adaptive antipredatory behavior can enhance fitness, but has some costs as well. Animals can either specifically react on the most dangerous predators (threat-sensitive avoidance) or they have safe but costly general wariness avoiding all potential predators. The level of threat may depend on the predator's foraging ecology and distribution with the prey with sympatric and specialist species being the most dangerous. We used 2 choice trials to investigate antipredatory behavior of captive born and wild-caught leopard geckos confronted with different snake predators from 2 families (Colubridae, Boidae) varying in foraging ecology and sympatric/allopatric distribution with the geckos. Predator-naïve subadult individuals have general wariness, explore both chemically and visually, and perform antipredatory postures toward a majority of snake predators regardless of their sympatry/allopatry or food specialization. The most exaggerated antipredatory postures in both subadult and adult geckos were toward 2 sympatric snake species, the spotted whip snake Hemorrhois ravergieri, an active forager, and the red sand boa Eryx johnii, a subterranean snake with a sit-and-wait strategy. In contrast, also subterranean but allopatric the Kenyan sand boa Eryx colubrinus did not elicit any antipredatory reaction. We conclude that the leopard gecko possesses an innate general antipredatory reaction to different species of snake predators, while a specific reaction to 2 particular sympatric species can be observed. Moreover, adult wild caught geckos show lower reactivity compared with the captive born ones, presumably due to an experience of a real predation event that can hardly be simulated under laboratory conditions.
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Affiliation(s)
- Eva Landová
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, 128 44 Prague, Czech Republic and.,National Institute of Mental Health, Topolová 748, 250 67 Klecany, Czech Republic
| | - Veronika Musilová
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, 128 44 Prague, Czech Republic and
| | - Jakub Polák
- National Institute of Mental Health, Topolová 748, 250 67 Klecany, Czech Republic
| | - Kristýna Sedláčková
- National Institute of Mental Health, Topolová 748, 250 67 Klecany, Czech Republic
| | - Daniel Frynta
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, 128 44 Prague, Czech Republic and.,National Institute of Mental Health, Topolová 748, 250 67 Klecany, Czech Republic
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Variation in Abundance and Efficacy of Tadpole Predators in a Neotropical Pond Community. J HERPETOL 2016. [DOI: 10.1670/14-111] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails. PLoS One 2016; 11:e0147017. [PMID: 26771658 PMCID: PMC4714930 DOI: 10.1371/journal.pone.0147017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 12/27/2015] [Indexed: 11/23/2022] Open
Abstract
Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs) of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in “100 of the World's Worst Invasive Alien Species”; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest “attack rates” a, shortest “handling times” h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach.
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Griffin JN, Toscano BJ, Griffen BD, Silliman BR. Does relative abundance modify multiple predator effects? Basic Appl Ecol 2015. [DOI: 10.1016/j.baae.2015.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Brahma S, Sharma D, Kundu M, Saha N, Saha GK, Aditya G. Intraguild Predation in Heteroptera: Effects of Density and Predator Identity on Dipteran Prey. NEOTROPICAL ENTOMOLOGY 2015; 44:374-384. [PMID: 26174962 DOI: 10.1007/s13744-015-0286-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 03/07/2015] [Indexed: 06/04/2023]
Abstract
In tropical freshwaters, different species of water bugs (Heteroptera) constitute a guild sharing similar prey resources including chironomid and mosquito larvae. Assuming possibilities of intraguild predation (IGP) among the constituent members, an attempt was made to evaluate the effects of prey and predator density on the mortality of mosquito and chironomid larvae (shared prey), using Laccotrephes griseus Guérin-Méneville (Hemiptera: Nepidae) and Ranatra filiformis Fabricius (Hemiptera: Nepidae) as IG predators and Anisops bouvieri Kirkaldy (Hemiptera: Notonectidae) as IG prey. The predation on mosquito and chironomid larvae varied with the density and combinations of the predators. When present as conspecific IG predators, L. griseus exhibited greater effect on the prey mortality than R. filiformis. The effects on shared prey suggest that the two predators are not substitutable in terms of the effect on the shared prey mortality. The mortality of A. bouvieri (IG prey) at low shared prey density was significantly different (p < 0.05) from high shared prey density. In view of predatory effect of the heteropteran predators on the dipteran larvae, the results suggest possible interference by the presence of A. bouvieri as an intermediate predator. It seems that the presence of heteropteran predators including A. bouvieri as IG prey may benefit the dipteran prey under situations when the density is low in tropical waters. The intensity of the predatory effect may differ based on the species composition at IG predator level. For mosquito biological control, the interactions between the predators may not be substitutable and are independent in their effects.
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Affiliation(s)
- S Brahma
- Dept of Zoology, Univ of Calcutta, Kolkata, India
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Garzon-Lopez CX, Ballesteros-Mejia L, Ordoñez A, Bohlman SA, Olff H, Jansen PA. Indirect interactions among tropical tree species through shared rodent seed predators: a novel mechanism of tree species coexistence. Ecol Lett 2015; 18:752-760. [PMID: 25939379 DOI: 10.1111/ele.12452] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/01/2015] [Accepted: 04/14/2015] [Indexed: 11/27/2022]
Abstract
The coexistence of numerous tree species in tropical forests is commonly explained by negative dependence of recruitment on the conspecific seed and tree density due to specialist natural enemies that attack seeds and seedlings ('Janzen-Connell' effects). Less known is whether guilds of shared seed predators can induce a negative dependence of recruitment on the density of different species of the same plant functional group. We studied 54 plots in tropical forest on Barro Colorado Island, Panama, with contrasting mature tree densities of three coexisting large seeded tree species with shared seed predators. Levels of seed predation were far better explained by incorporating seed densities of all three focal species than by conspecific seed density alone. Both positive and negative density dependencies were observed for different species combinations. Thus, indirect interactions via shared seed predators can either promote or reduce the coexistence of different plant functional groups in tropical forest.
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Affiliation(s)
- Carol X Garzon-Lopez
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Box 11103, Groningen, 9700 CC, The Netherlands.,GIS and Remote Sensing Unit, Department of Biodiversity and Molecular Ecology, Fondazione Edmund Mach, Research and Innovation Centre, Via E. Mach 1, 38010 S. Michele all'Adige (TN), Italy
| | - Liliana Ballesteros-Mejia
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Box 11103, Groningen, 9700 CC, The Netherlands.,Laboratorio de Genetica e Biodiversidade, ICB, Universidade Federal de Goias (UFG), Campus Samambaia 74001-970 Goiania, Goias, Brazil
| | - Alejandro Ordoñez
- Department of Bioscience, Section for Ecoinformatics and Biodiversity, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark
| | - Stephanie A Bohlman
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Ancon, Republic of Panama.,School of Forest Resources and Conservation, University of Florida, Box 110410, Gainesville, FL, 32611-0410, USA
| | - Han Olff
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Box 11103, Groningen, 9700 CC, The Netherlands
| | - Patrick A Jansen
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Box 11103, Groningen, 9700 CC, The Netherlands.,Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Ancon, Republic of Panama.,Department of Environmental Sciences, Wageningen University, Box 47, 6700, AA Wageningen, The Netherlands
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Abstract
Multiple invasive species have now established at most locations around the world, and the rate of new species invasions and records of new invasive species continue to grow. Multiple invasive species interact in complex and unpredictable ways, altering their invasion success and impacts on biodiversity. Incumbent invasive species can be replaced by functionally similar invading species through competitive processes; however the generalized circumstances leading to such competitive displacement have not been well investigated. The likelihood of competitive displacement is a function of the incumbent advantage of the resident invasive species and the propagule pressure of the colonizing invasive species. We modeled interactions between populations of two functionally similar invasive species and indicated the circumstances under which dominance can be through propagule pressure and incumbent advantage. Under certain circumstances, a normally subordinate species can be incumbent and reject a colonizing dominant species, or successfully colonize in competition with a dominant species during simultaneous invasion. Our theoretical results are supported by empirical studies of the invasion of islands by three invasive Rattus species. Competitive displacement is prominent in invasive rats and explains the replacement of R. exulans on islands subsequently invaded by European populations of R. rattus and R. norvegicus. These competition outcomes between invasive species can be found in a broad range of taxa and biomes, and are likely to become more common. Conservation management must consider that removing an incumbent invasive species may facilitate invasion by another invasive species. Under very restricted circumstances of dominant competitive ability but lesser impact, competitive displacement may provide a novel method of biological control.
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