@article {993,
	title = {Invertebrate predators of the jack-pine budworm, Choristoneura pinus, in Michigan},
	journal = {Annals of the Entomological Society of America},
	volume = {63},
	year = {1970},
	month = {1970///},
	pages = {59 - 64},
	keywords = {INVERTEBRATE PREDATORS, MICHIGAN, PREDATOR, predators},
	author = {Allen,D.C. and Knight,F.B. and Foltz,J.L.}
}
@article {967,
	title = {How leaf domatia and induced plant resistance affect herbivores, natural enemies and plant performance},
	journal = {Oikos},
	volume = {89},
	year = {2000},
	note = {Journal
English
Article
MUNKSGAARD INT PUBL LTD
3
APR
299ZB
COPENHAGEN
Agrawal AA Univ Toronto, Dept Bot, 25 Willcocks St, Toronto, ON M5S 3B2, Canada
OIKOS
35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK},
	month = {2000///},
	pages = {70 - 80},
	abstract = {Predators and plant resistance may act together to control herbivorous arthropod populations or antagonistically, which would reduce the control of pest populations. In a field experiment we enhanced predation by adding simulated leaf domatia to plants. Leaf domatia are small structures that often harbor predaceous arthropods that are potentially beneficial to the plant. We also manipulated host plant duality by inducing resistance with controlled. early season exposure of seedlings to spider mite herbivory. Our manipulations had profound consequences for the natural community of arthropods that inhabited the plants. Leaf domatia had a direct positive effect on abundances of two species of bugs and one species of thrips, all of which are largely predators of herbivores. On leaves with domatia, each of the predators was found inside the domatia two to three times more often than outside the domatia. Eggs of predaceous bugs inside leaf domatia were protected from parasitism compared to eggs outside the domatia. The positive effects of leaf domatia on predator abundances were associated with reduced populations of herbivorous spider mites, aphids, and whiteflies. Plants with experimental leaf domatia showed significantly enhanced reproductive performance. Induced resistance also affected the community of arthropods. Of the abundant predators, all of which also fed on the plant, only minute pirate bugs were negatively affected by induced resistance. Populations of herbivorous spider mites and whiteflies were directly and negatively affected by induction. In contrast, aphid populations were higher on plants with induced resistance compared to uninduced plants. Effects of induced resistance and domatia were additive for each of the predators and for aphids. However, spider mite and whitefly populations were not suppressed Further by employing both induced resistance and domatia compared to each strategy alone. Our manipulations suggest that plant defense strategies can have positive effects on some species and negative effects on others. Negative effects of "resistance trails" on predators and positive effects on some herbivores may reduce the benefits of constitutive expression of resistance traits and may favor inducible defense strategies. Multiple plant strategies such as inducible resistance and morphological traits that aid in the recruitment of predators of herbivores may act together to maximize plant defenses, although they may also be redundant and not act additively},
	keywords = {BIOLOGICAL-CONTROL, COMMUNITIES, COMMUNITY, CONSEQUENCES, COTTON, DECIDUOUS FOREST, DEFENSE STRATEGY, FLOWER THRIPS, food webs, herbivory, HOST-PLANT, multiple, MUTUALISM, NATURAL ENEMIES, POPULATIONS, predation, PREDATOR, predators, RECRUITMENT, SEEDLINGS, SPIDER-MITES, TROPHIC LEVELS},
	isbn = {0030-1299},
	url = {ISI:000086227400008},
	author = {Agrawal,A.A. and Karban,R. and Colfer,R.G.}
}
@article {939,
	title = {Trait-initiated indirect effects due to changes in consumption rates in simple food webs},
	journal = {Ecology},
	volume = {85},
	year = {2004},
	note = {J
APR},
	month = {2004///},
	pages = {1029 - 1038},
	abstract = {This article explores the potential indirect effects due to changes in consumption-related traits of a focal prey species in each of two simple food webs. The systems considered are: one predator exploiting two independent prey, and one predator exploiting two prey that use a common limiting resource. In each system, the indirect effect of a change in a consumption-related parameter of one prey species on the population density of the other prey is determined. When prey only share a predator, the change in one prey{\textquoteright}s density produced by a change in the other prey{\textquoteright}s vulnerability to the predator is determined by whether or not that second prey is initially overexploited; i.e., whether its exploiter{\textquoteright}s intake decreases with an increase in the attack rate. Increases in the vulnerability of an overexploited prey decrease the predator population and thereby indirectly increase the population size of the second prey. Increases in the vulnerability of a prey that is not overexploited have the opposite effects on both the predator and second prey populations. Both of these outcomes can be reversed by strong direct density dependence in the predator, provided the predator exhibits satiation. In the food web with a shared food and a shared resource, increases in predator vulnerability of the more vulnerable prey species always increase the population size of the more resistant prey species. However, increases in the vulnerability of the more resistant prey can either increase or decrease the population size of the more vulnerable prey species. When the more resistant prey becomes better at capturing the resource, the less resistant may either increase or decrease. Overexploitation also explains these outcomes. General principles for understanding the consequences of changes in vulnerabilities or attack rates are discussed},
	keywords = {CONSEQUENCES, DENSITY, DENSITY DEPENDENCE, DENSITY-DEPENDENCE, DEPENDENCE, food web, food webs, FOOD-WEB, indirect effects, POPULATIONS, PREDATOR, PREY, SIZE},
	isbn = {0012-9658},
	url = {ISI:000220766600014},
	author = {Abrams,P.A.}
}
@article {1120,
	title = {The effect of temporal scale on the outcome of trophic cascade experiments},
	journal = {Oecologia},
	volume = {134},
	year = {2003},
	note = {J
MAR},
	month = {2003///},
	pages = {578 - 586},
	abstract = {The outcome of experimental manipulations in ecology should depend on the duration of the experiment. We tested this proposition by examining the results of published trophic cascade experiments in freshwater communities and the results of our own previously unpublished pond experiment. In particular, we analyze the results of 90 published trophic cascade experiments to test the prediction that the outcome of freshwater trophic cascade experiments, in which zooplanktivorous fish are either present or absent, depends on the duration of the experiment. We present evidence that there are quantitative differences in the strength of trophic cascades among different venue types (enclosure, mesocosm, pond, and lake), but that the strength of trophic cascades does not diminish with increasing experiment duration. Despite the large number of studies, there have been few replicated studies of trophic cascades for longer than a summer field season, and none for the time required to estimate the long-term result of press perturbations. We therefore present the results of a 4-year study of trophic cascades in experimental ponds, to test the predictions that the addition of the top predator results in a sustained increase in the phytoplankton biomass. We found that, as predicted by our literature review, there was no decline in the strength of the trophic cascade as the experiment progressed},
	keywords = {COMMUNITIES, COMMUNITY, ecology, PREDATOR, SCALE, TOP, trophic cascade, trophic cascades},
	isbn = {0029-8549},
	url = {ISI:000181582700016},
	author = {Bell,T. and Neill,W.E. and Schluter,D.}
}
@article {940,
	title = {Defining and measuring the impact of dynamic traits on interspecific interactions},
	journal = {Ecology},
	volume = {88},
	year = {2007},
	note = {J
OCT},
	month = {2007///},
	pages = {2555 - 2562},
	abstract = {Trait- and density-mediated indirect effects describe different pathways by which indirect interactions in food webs are propagated from one species to another, through changes in intermediate species. A series of articles in Ecology has progressively altered the original definitions of "trait-mediated{\textquoteright}{\textquoteright} to the point where understanding is being impeded. The most recent of these articles are two meta-analyses that use "trait-mediated{\textquoteright}{\textquoteright} to describe the demographic costs to a prey species of employing anti-predator defenses. These same articles introduce a companion term, "density-mediated interaction,{\textquoteright}{\textquoteright} apparently to describe direct and indirect interactions that only involve changes in population density due to consumption by predators. This new terminology has many disadvantages, including ( 1) using a general term for a relatively narrow group of processes; ( 2) using "mediated{\textquoteright}{\textquoteright} in a manner inconsistent with existing terminology; ( 3) confusing the accepted definitions of different types of indirect effects; and ( 4) providing a highly incomplete measure of the impact of behavior on the predator - prey interaction. Solutions to these problems and the meaning of the meta-analyses are discussed},
	keywords = {defense, ecology, food webs, indirect effects, indirect interactions, interactions, INTERSPECIFIC INTERACTIONS, PREDATOR, predators, PREY},
	isbn = {0012-9658},
	url = {ISI:000250714200016},
	author = {Abrams,P.A.}
}
@article {942,
	title = {Measuring the impact of dynamic antipredator traits on predator-prey-resource interactions},
	journal = {Ecology},
	volume = {89},
	year = {2008},
	note = {J
JUN},
	month = {2008///},
	pages = {1640 - 1649},
	abstract = {This article analyzes the limitations of the most widely used method for quantifying the impact of dynamic antipredator traits on food chain dynamics and discusses alternative approaches. The standard method for a predator-prey-resource chain estimates the effects of the prey{\textquoteright}s defensive behavior by comparing population densities or fitness measures in a {\textquoteright}{\textquoteright}predator cue{\textquoteright}{\textquoteright} treatment to those in a no-predator treatment. This design has been interpreted as providing a measure of the {\textquoteright}{\textquoteright}nonconsumptive effect{\textquoteright}{\textquoteright} of the predator on the prey and the {\textquoteright}{\textquoteright}trait-mediated indirect effect{\textquoteright}{\textquoteright} of the predator on the resource. Other approaches involve measurements of the impact of the behavior in the presence of functional predators. The questions addressed here are: (1) How consistent are the results of different approaches? (2) How time-dependent are their results? (3) How well do they correspond to theoretical measures of effect size? (4) How useful are the measurements in understanding system dynamics? A model of a tritrophic system in which the prey species adjusts a defensive trait adaptively is used to evaluate the experimental designs. Measures of changes in prey fitness or population density in a cue treatment generally include offsetting effects of the cost of the behavior and the benefit of more resources. This means that the sign of the effect, as well as its magnitude, may change depending on when the experiment is terminated. Because predation is not present in the cue treatment, few conclusions can be drawn about the impact of the behavior on population densities or fitness of the prey in a natural setting with predators. Cue experiments often do not accurately separate trait-mediated from density-mediated effects on the resource. Most scalar measures of effects are sensitive to experimental duration and initial densities. Use of a wider range of experimental designs to measure trait-related effects is called for},
	keywords = {DYNAMICS, interactions, predation, PREDATOR, predators, PREY, SIZE},
	isbn = {0012-9658},
	url = {ISI:000256540300017},
	author = {Abrams,P.A.}
}
@article {943,
	title = {Measuring the population-level consequences of predator-induced prey movement},
	journal = {Evolutionary Ecology Research},
	volume = {10},
	year = {2008},
	note = {J
MAR},
	month = {2008///},
	pages = {333 - 350},
	abstract = {Questions: (1) What impact does adaptive movement away from areas of high predation risk have on the dynamics of a prey species and its resource? (2) What can experiments that introduce or remove predator cues tell us about the answer to question (1)? Mathematical methods: These questions are addressed using a two-patch meta-community model in which predators and/or their cues are incorporated into a system consisting of a prey species and its resource. Predators and/or cues may be introduced to one or both patches. Key assumptions: Prey species move adaptively to maximize their instantaneous rate of increase, but also make some random movement. Predators move randomly or do not move. Resources seldom or never move between patches. Consumer species have saturating functional responses. Conclusions: (1) Adaptive movement can stabilize or destabilize the dynamics of the tri-trophic system. (2) Monitoring densities in a single patch may give a misleading indication of the global change in densities. (3) Adaptive prey movement in response to predator cues may increase or decrease prey density. (4) Predator introduction may cause an increase or decrease in the size of the prey population. (5) Short-term experiments with local measurements may greatly overestimate the impact of predators on prey and the behavioural component of that impact. (6) The dynamics and interspecific effects in a system with predators and adaptive avoidance by prey cannot in general be deduced from separate experiments with cues alone and with predators in the absence of the cues. (7) Conclusions from recent empirical studies should be reassessed in light of these results},
	keywords = {CONSEQUENCES, DYNAMICS, predation, PREDATOR, predators, PREY, RISK, SIZE},
	isbn = {1522-0613},
	url = {ISI:000256015000002},
	author = {Abrams,P.A.}
}
@article {988,
	title = {Reappraisal of the role of big, fierce predators!},
	journal = {Biodiversity and conservation},
	volume = {17},
	year = {2008},
	note = {J
APR},
	month = {2008///},
	pages = {685 - 690},
	abstract = {The suggestion in the early 20th century that top predators were a necessary component of ecosystems because they hold herbivore populations in check and promote biodiversity was at first accepted and then largely rejected. With the advent of Evolutionary Ecology and a more full appreciation of direct and indirect effects of top predators, this role of top predators is again gaining acceptance. The previous views were predicated upon lethal effects of predators but largely overlooked their non-lethal effects. We suggest that conceptual advances coupled with an increased use of experiments have convincingly demonstrated that prey experience costs that transcend the obvious cost of death. Prey species use adaptive behaviours to avoid predators, and these behaviours are not cost-free. With predation risk, prey species greatly restrict their use of available habitats and consumption of available food resources. Effects of top predators consequently cascade down to the trophic levels below them. Top predators, the biggies, are thus both the targets of and the means for conservation at the landscape scale},
	keywords = {biodiversity, ecology, indirect effects, POPULATIONS, predation, PREDATOR, predators, PREY, RISK, TOP, TROPHIC LEVELS},
	isbn = {0960-3115},
	url = {ISI:000254360200001},
	author = {Ale,S.B. and Whelan,C.J.}
}
@article {927,
	title = {Spatial Variation in the Strength of a Trophic Cascade Involving Ruellia nudiflora (Acanthaceae), an Insect Seed Predator and Associated Parasitoid Fauna in Mexico},
	journal = {Biotropica},
	volume = {42},
	year = {2010},
	note = {J
MAR},
	month = {2010///},
	pages = {180 - 187},
	abstract = {Spatial variation in the strength of herbivore top-down control represents an important source of variation in plant fitness measures and community structure and function. By measuring seed predator (larvae of a Noctuid moth) and parasitoid impacts on Ruellia nudiflora across a broad spatial scale in Yucatan (Mexico), this study addressed the following: (1) to what extent does seed predator and parasitoid attack intensity associated with R. nudiflora vary spatially? (2) Does parasitoid attack result in a positive indirect effect on the plant, and does the intensity of this effect vary spatially? During the peak of fruit production (late June-early July) of 2005, we collected fruits from 21 R. nudiflora populations and grouped them into four regions: center, east, north and south. For each fruit we recorded: observed seed number, number of seeds eaten, seed predator presence, parasitoid presence and number of seeds {\textquoteright}{\textquoteleft}saved{\textquoteright} by parasitoids. Seed predators attacked ca 30 percent of fruits/plant on average, while parasitoids were found in 24 percent of seed predator-attacked fruits. Results indicated spatial variation in seed predator and parasitoid attack levels; interestingly, a contrasting spatial gradient of attack intensity was observed: populations/regions with greatest parasitoid attack levels usually had the lowest seed predator attack levels and vice versa, suggesting top-down control of parasitoids on seed predators. We observed a weak overall indirect impact of parasitoids on R. nudiflora (4\% seeds {\textquoteright}saved{\textquoteright} on average), which nonetheless varied strongly across populations (e.g., close to 14\% seeds saved at one population). Findings indicate a geographical structuring of interaction strengths across populations, as well as spatial variation in the strength of parasitoid cascading effects on plant reproduction},
	keywords = {COMMUNITIES, COMMUNITY, community structure, GRADIENT, HERBIVORE, impact, insect, larvae, MOTH, Parasitoid, parasitoids, plant, POPULATIONS, PREDATOR, predators, SCALE, TOP-DOWN, trophic cascade},
	isbn = {0006-3606},
	url = {ISI:000275215700007},
	author = {Abdala-Roberts,L. and Parra-Tabla,V. and Salinas-Peba,L. and Diaz-Castelazo,C. and Delfin-Gonzalez,H.}
}
