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Gratton Claudio - - 2006
Restoration of habitats impacted by invasive plants is becoming an increasingly important tool in the management of native biodiversity, though most studies do not go beyond monitoring the abundance of particular taxonomic groups, such as the return of native vegetation. Yet, the reestablishment of trophic interactions among organisms in restored ...
Darst Catherine R - - 2006
Many animals advertise their chemical defense to predators with conspicuous coloration and unpalatability, but little is known about the information in these signal elements. To effectively avoid predation, is it more advantageous to invest in increased conspicuousness or greater noxiousness, or to allocate equally to both signal modalities? Using natural ...
Katechakis Alexis - - 2006
Mixotrophic organisms combine light, mineral nutrients, and prey as supplementary resources. Based on theoretical assumptions and field observations, we tested experimentally the hypothesis that mixotrophs may invade established plankton communities depending on the trophic status of the system, and investigated possible effects on food web structure, species diversity, and nutrient ...
Lin Hsing-Juh - - 2006
Tapong Bay, a eutrophic and poorly flushed tropical lagoon, supports intensive oyster culture. Using the Ecopath approach and network analysis, a mass-balanced trophic model was constructed to analyze the structure and matter flows within the food web. The lagoon model is comprised of 18 compartments with the highest trophic level ...
Tewksbury Joshua J - - 2006
The effects of landscape fragmentation on nest predation and brood parasitism, the two primary causes of avian reproductive failure, have been difficult to generalize across landscapes, yet few studies have clearly considered the context and spatial scale of fragmentation. Working in two river systems fragmented by agricultural and rural-housing development, ...
Virgo Nathaniel - - 2006
1. Successional changes during sequential assembly of food webs were examined. This was carried out by numerical methods, drawing one species at a time from a species pool and obtaining the permanent (persistent) community emerging at each step. Interactions among species were based on some simple rules about body sizes ...
Meissner Kristian - - 2006
1. We evaluated the effects of brown trout on boreal stream food webs using field surveys and enclosure/exclosure experiments. Experimental results were related to prey preference of uncaged trout in the same stream, as well as to a survey of macroinvertebrate densities in streams with vs. without trout. Finally, we ...
Elser James J - - 2006
Here we use the theory of ecological stoichiometry to propose and provide a preliminary test of a novel hypothesis that the Cambrian 'explosion' may have been triggered by changes in circulating P availability in the biosphere. We exposed living stromatolites from a spring-fed stream in Mexico to a gradient of ...
Haugstvedt Jan-Ragnar - - 2006
PURPOSE: Laboratory studies evaluating the importance of the stabilizing structures of the distal radioulnar joint (DRUJ) largely have been limited to static design. Clinically, dynamic loading seems to be an important component of DRUJ instability. This study was designed to evaluate the influence of dynamic loading on the stability of ...
Niessen L - - 2006
Ochratoxin A (OTA) can be detected worldwide from various food and feed sources. It is produced byPenicillium nordicum andP. verrucosum as well as by variousAspergillus species, withA. ochraceus andA. carbonarius as the predominant producers. Various pairs of PCR primers based on AFLP, RAPD as well as primers specific to ribosomal ...
Essington Timothy E - - 2006
A recurring pattern of declining mean trophic level of fisheries landings, termed "fishing down the food web," is thought to be indicative of the serial replacement of high-trophic-level fisheries with less valuable, low-trophic-level fisheries as the former become depleted to economic extinction. An alternative to this view, that declining mean ...
Gilman Sarah E - - 2006
Experimental studies of biogeographic processes are important, but rarely attempted because of the logistical challenges of research at large spatial scales. I used a series of large-scale transplant experiments to investigate the mechanisms controlling species abundance near a poleward range boundary. The intertidal limpet Collisella scabra experiences a 100-fold decline ...
Rossberg A G - - 2006
Food webs of habitats as diverse as lakes or desert valleys are known to exhibit common "food-web patterns", but the detailed mechanisms generating these structures have remained unclear. By employing a stochastic, dynamical model, we show that many aspects of the structure of predatory food webs can be understood as ...
Bergman Eric J - - 2006
Within predator-prey systems behavior can heavily influence spatial dynamics, and accordingly, the theoretical study of how spatial dynamics relate to stability within these systems has a rich history. However, our understanding of these behaviors in large mammalian systems is poorly developed. To address the relationship between predator selection patterns, prey ...
Werner Earl E - - 2006
Indirect effects propagated through intervening species in a food web have important effects on community properties. Traditionally, these indirect effects have been conceptualized as mediated through density changes of the intervening species, but it is becoming increasingly apparent that those mediated through trait (phenotypic) responses also can be very important. ...
Straub Cory S - - 2006
Agricultural pest suppression is an important ecosystem service that may be threatened by the loss of predator diversity. This has stimulated interest in the relationship between predator biodiversity and biological control. Multiple-predator studies have shown that predators may complement or interfere with one another, but few experiments have determined if ...
Matsuda Hiroyuki - - 2006
Increasing centralization of the control of fisheries combined with increased knowledge of food-web relationships is likely to lead to attempts to maximize economic yield from entire food webs. With the exception of predator-prey systems, we lack any analysis of the nature of such yield-maximizing strategies. We use simple food-web models ...
Veiga Liza M - - 2006
Bearded sakis are seed predators, but are also known to consume arthropods. This is the first detailed report of arthropod predation in southern bearded sakis (Chiropotes satanas). Two groups were monitored-one in continuous forest, and one on a small island-between January 2003 and February 2004. The arthropod prey included spiders ...
Zanette Liana - - 2006
Food and predators have traditionally been viewed as mutually exclusive alternatives when considering factors affecting animal populations. This has led to long controversies such as whether annual reproductive success in songbirds is primarily a function of food-restricted production or predator-induced loss. Recent studies on both birds and mammals suggest many ...
Brodin Tomas - - 2006
A central issue in predator-prey interactions is how predator associated chemical cues affect the behaviour and life history of prey. In this study, we investigated how growth and behaviour during ontogeny of a damselfly larva (Coenagrion hastulatum) in high and low food environments was affected by the diet of a ...
Wang Wendi - - 2006
A stage structure is incorporated into a prey-predator model in which predators are split into immature predators and mature predators. It is assumed that immature predators are raised by their parents in the sense that they cannot catch the prey and their foods are provided by parents. Further, it is ...
Shurin Jonathan B - - 2006
Ecologists have greatly advanced our understanding of the processes that regulate trophic structure and dynamics in ecosystems. However, the causes of systematic variation among ecosystems remain controversial and poorly elucidated. Contrasts between aquatic and terrestrial ecosystems in particular have inspired much speculation, but only recent empirical quantification. Here, we review ...
Dehn Larissa-A - - 2006
Tissues of subsistence-harvested Arctic mammals were analyzed for silver (Ag), cadmium (Cd), and total mercury (THg). Muscle (or total body homogenates of potential fish and invertebrate prey) was analyzed for stable carbon (delta13C) and nitrogen (delta15N) isotopes to establish trophic interactions within the Arctic food chain. Food web magnification factors ...
Boersma, Maarten
pg. V-IX Winfried Lampert: Natural selection is ecology in action. Boersma M. Santer B. 1 pg. 1-20 Selective advantage of irreversible and reversible phenotypic plasticity. Gabriel W. 2 pg. 21-35 Predator-mediated life history shifts in Daphnia: enrichment and preliminary chemical characterisation of a kairomone exuded by fish. Von Bert E. ...
Molinero, J.C.
Identifying mediator factors linking climate changes and ecological processes in pelagic food-webs is a major challenge in ecology and resources management. Here, we have investigated how climate variability affects marine and limnic ecosystems. We used a downscaling and time-series modelling approach in which we analyzed different spatial scales of climate ...
Havens Karl E - - 2006
During two controlled enclosure experiments using water from a subtropical lake, the plankton food web displayed a highly variable response to combined addition of nitrogen and phosphorus. In July, the nutrients stimulated growth of Cylindrospermopsis raciborskii, and the biomass of macrozooplankton and microbial food web components did not increase. In ...
Worden Alexandra Z - - 2006
Cholera disease, caused by the bacterium Vibrio cholerae, afflicts hundreds of thousands worldwide each year. Endemic to aquatic environments, V. cholerae's proliferation and dynamics in marine systems are not well understood. Here, we show that under a variety of coastal seawater conditions V. cholerae remained primarily in a free-living state ...
Hill R A - - 2006
As a behavioural strategy, cathemerality is thought to confer considerable advantages by allowing animals to extend activity flexibly into either the diurnal or nocturnal phase in response to the prevailing ecological conditions. Factors such as temperature, access to food sources and minimising the risk of predation are all thought to ...
Preston Kristine L - - 2006
We investigated the relative importance and interaction of ecological processes affecting annual fecundity in birds by simultaneously manipulating food availability and nest predation risk in a small songbird, the Wrentit (Chamaea fasciata). From 2000 to 2002 we provided supplemental food to individual Wrentit territories, and during 2002 we altered nest ...
Sims David W - - 2006
1. Diel vertical migration (DVM) is a widespread phenomenon among marine and freshwater organisms and many studies with various taxa have sought to understand its adaptive significance. Among crustacean zooplankton and juveniles of some fish species DVM is accepted widely as an antipredator behaviour, but little is known about its ...
Sasko Desirée E - - 2006
The structurally reinforced jaws of the cownose ray, Rhinoptera bonasus testify to this species' durophagous diet of mollusks, but seem ill-suited to the behaviors necessary for excavating such prey. This study explores this discordance by investigating the prey excavation and capture kinematics of R. bonasus. Based on the basal suction ...
Mayntz David - - 2006
1. Cannibalism is considered an adaptive foraging strategy for animals of various trophic positions, including carnivores. However, previous studies on wolf spiders have questioned the high nutritional value of cannibalism. We therefore analysed two different aspects of nutritional quality of conspecifics in the wolf spider Pardosaprativaga: their value for survival, ...
Negishi Junjiro N - - 2006
1. The passive or active movement of organisms between habitat patches plays important roles in achieving ecosystem resilience to disturbance and long-term control of population levels. However, causal mechanisms of disturbance-induced movements of mobile biota across heterogeneous habitat patches at a relatively short time-scale are little understood. 2. We experimentally ...
Van Son Thijs Christiaan - - 2006
1. We examined the effects of multiple predators from an intertidal boulder food web to test whether and how three different predator species affected the survival of a small amphipod species. 2. Predators were chosen because they differ in their foraging mode, two feeding at the bottom and in benthic ...
Wise David H - - 2006
Cannibalism among generalist predators has implications for the dynamics of terrestrial food webs. Spiders are common, ubiquitous arthropod generalist predators in most natural and managed terrestrial ecosystems. Thus, the relationship of spider cannibalism to food limitation, competition, and population regulation has direct bearing on basic ecological theory and applications such ...
van Veen F J Frank - - 2006
Phytophagous insects and their natural enemies make up one of the largest and most diverse groups of organisms on earth. Ecological processes, in particular negative indirect effects mediated by shared natural enemies (apparent competition), may be important in structuring phytophagous insect communities. The potential for indirect interactions can be assessed ...
De Vis R M J - - 2006
The objective of this study was to evaluate the oviposition rate and the survivorship of some of the most common predators on plants of the natural vegetation of southeastern Brazil, when confined with different food sources. Forty-four laboratory tests were carried out, each corresponding to a different combination of predator ...
Miller David A - - 2006
1. Predation plays an integral role in many community interactions, with the number of predators and the rate at which they consume prey (i.e. their functional response) determining interaction strengths. Owing to the difficulty of directly observing predation events, attempts to determine the functional response of predators in natural systems ...
Hodges Karen E - - 2006
1. Overwinter mass loss can reduce energetic requirements in mammals (Dehnel's phenomenon). Alternatively, mass loss can result from food limitation or high predation risk. 2. We use data from fertilizer, food-supplementation and predator-exclusion experiments in the Yukon during a population cycle from 1986 to 1996 to test the causes of ...
Saloranta Tuomo M - - 2006
Rate constant bioaccumulation models are applied to simulate the flow of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the coastal marine food web of Frierfjorden, a contaminated fjord in southern Norway. We apply two different ways to parameterize the rate constants in the model, global sensitivity analysis of the models using ...
Kubodera Tsunemi - - 2005
The giant squid, Architeuthis, is renowned as the largest invertebrate in the world and has featured as an ominous sea monster in novels and movies. Considerable efforts to view this elusive creature in its deep-sea habitat have been singularly unsuccessful. Our digital camera and depth recorder system recently photographed an ...
Cai Deling - - 2005
Stable carbon and nitrogen isotope ratios (delta (13)C and delta (15)N) are used to study the trophic structure of food web in the Yellow Sea and East China Sea ecosystem. The trophic continuum of pelagic food web from phytoplankton to top preyer was elementarily established, and a trophic structure diagram ...
Ratcliffe John M - - 2005
We studied the efficiency and effects of the multiple sensory cues of tiger moths on echolocating bats. We used the northern long-eared bat, Myotis septentrionalis, a purported moth specialist that takes surface-bound prey (gleaning) and airborne prey (aerial hawking), and the dogbane tiger moth, Cycnia tenera, an eared species unpalatable ...
Getto Ph - - 2005
Cannibalism is an interaction between individuals that can produce counter- intuitive effects at the population level. A striking effect is that a population may persist under food conditions such that the non-cannibalistic variant is doomed to go extinct. This so-called life boat mechanism has received considerable attention. Implicitly, such studies ...
van Kooten Tobias - - 2005
The Allee effect, a reduction of individual fitness at low population density that can lead to sudden and unannounced extinctions, has been shown to come about through a number of mechanisms, usually associated with group behavior or mate search. Recent papers show that it may arise through size-selective predation, without ...
Matz Carsten - - 2005
Persistence of the opportunistic bacterial pathogen Vibrio cholerae in aquatic environments is the principal cause for seasonal occurrence of cholera epidemics. This causality has been explained by postulating that V. cholerae forms biofilms in association with animate and inanimate surfaces. Alternatively, it has been proposed that bacterial pathogens are an ...
Freire Botana, Juan Manuel
Patterns of habitat use by spider crab juveniles, Maja brachydactila, from two geographic areas in the NW coast of the Iberian Peninsula, were analyzed through the analysis of Carbon and Nitrogen stable isotope relations in two tissues (muscle and hepatopancreas). The main organisms that constitute the diet of spider crab ...
Freire Botana, Juan Manuel
Patterns of habitat use by spider crab juveniles, Maja brachydactila, from two geographic areas in the NW coast of the Iberian Peninsula, were analyzed through the analysis of Carbon and Nitrogen stable isotope relations in two tissues (muscle and hepatopancreas). The main organisms that constitute the diet of spider crab ...
Fonda Umani Serena - - 2005
The temporal dynamics of microphytoplankton, microzooplankton and mesozooplankton were monitored over 37 months in the Adriatic Sea in order to identify alterations in the plankton structures, which can lead to, or enhance the production of macro-aggregates, that affected the entire northern basin in summers 2000 and 2002, and to assess ...
Hulot Florence D - - 2006
Community structure is controlled, among multiple factors, by competition and predation. Using the R* rule and graphical analysis, we analyse here the feasibility, stability and assembly rules of resource-based food webs with up to three trophic levels. In particular, we show that (1) the stability of a food web with ...
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