PRODUCTIVITY, INTRAGUILD PREDATION, AND POPULATION DYNAMICS IN EXPERIMENTAL FOOD WEBS

Ecology ◽  
1999 ◽  
Vol 80 (3) ◽  
pp. 752-760 ◽  
Author(s):  
Peter Morin
Keyword(s):  
Population Dynamics ◽  
Food Webs ◽  
Intraguild Predation

More Modules

2011 ◽  
Author(s):  
Kevin S. McCann
Keyword(s):  
Population Dynamics ◽  
Food Webs ◽  
Empirical Evidence ◽  
Intraguild Predation ◽  
Weak Interactions ◽  
Apparent Competition ◽  
Trade Offs ◽  
Variable Population ◽  
The Stability

This chapter considers four-species modules and the role of generalism (effectively a three-species module with a consumer feeding on two resources). It first examines how generalists affect the dynamics of food webs by focusing on a set of modules that contrast generalist consumer dynamics relative to the specialist case. It then discusses organismal trade-offs that play a role in governing the diamond food web module and the intraguild predation module, arguing that such tradeoffs influence the flux of matter, the organization of interaction strengths, and ultimately the stability of communities. The chapter also reviews empirical evidence showing that apparent competition and the diamond module with and without intraguild predation are ubiquitous, and that weak interactions in simple modules seem to promote less variable population dynamics.

scholarly journals POPULATION DYNAMICS ON COMPLEX FOOD WEBS

2011 ◽  
Vol 14 (04) ◽  
pp. 635-647 ◽  
Author(s):  
GIAN MARCO PALAMARA ◽  
VINKO ZLATIĆ ◽  
ANTONIO SCALA ◽  
GUIDO CALDARELLI
Keyword(s):  
Population Dynamics ◽  
Simple Model ◽  
Food Web ◽  
Food Webs ◽  
Real Data ◽  
Niche Model ◽  
Ecological Complexity ◽  
Overlap Graphs ◽  
Dynamical Properties ◽  
The Stability

In this work we analyze the topological and dynamical properties of a simple model of complex food webs, namely the niche model. In order to underline competition among species, we introduce "prey" and "predators" weighted overlap graphs derived from the niche model and compare synthetic food webs with real data. Doing so, we find new tests for the goodness of synthetic food web models and indicate a possible direction of improvement for existing ones. We then exploit the weighted overlap graphs to define a competition kernel for Lotka–Volterra population dynamics and find that for such a model the stability of food webs decreases with its ecological complexity.

Host-Parasitoid Interactions

Ecology ◽  
2013 ◽  
Author(s):  
Jeffrey A. Harvey
Keyword(s):  
Population Dynamics ◽  
Food Webs ◽  
20Th Century ◽  
Host Species ◽  
Trophic Levels ◽  
Diverse Group ◽  
Ecological Communities ◽  
Major Focus ◽  
Species Identity ◽  
Wide Range

Insects are a highly diverse group due to their ability to exploit a wide range of niches. Each plant is attacked by multiple herbivores and these in turn may harbor a bewildering complexity of natural enemies, particularly parasitoids, which are often quite specialized in terms of the host species identity (and stage of attack) of their hosts. Furthermore, these parasitoids have their own parasitoids that attack them, meaning that food webs including these insects may go up to five trophic levels (or even more). Due to their diversity and strong link population dynamics, parasitoids comprise important aspects of ecological communities. Because of this and their potential as biocontrol agents, host-parasitoid dynamics have been a major focus of ecological and evolutionary study since the beginning of the 20th century.

scholarly journals Parasites that change predator or prey behaviour can have keystone effects on community composition

2014 ◽  
Vol 10 (1) ◽  
pp. 20130879 ◽  
Author(s):  
Melanie J. Hatcher ◽  
Jaimie T. A. Dick ◽  
Alison M. Dunn
Keyword(s):  
Population Dynamics ◽  
Community Structure ◽  
Mathematical Models ◽  
Biological Invasions ◽  
Intraguild Predation ◽  
Host Species ◽  
Indirect Interactions ◽  
Ecological Impacts ◽  
Mediated Effects ◽  
Population Interactions

Parasites play pivotal roles in structuring communities, often via indirect interactions with non-host species. These effects can be density-mediated (through mortality) or trait-mediated (behavioural, physiological and developmental), and may be crucial to population interactions, including biological invasions. For instance, parasitism can alter intraguild predation (IGP) between native and invasive crustaceans, reversing invasion outcomes. Here, we use mathematical models to examine how parasite-induced trait changes influence the population dynamics of hosts that interact via IGP. We show that trait-mediated indirect interactions impart keystone effects, promoting or inhibiting host coexistence. Parasites can thus have strong ecological impacts, even if they have negligible virulence, underscoring the need to consider trait-mediated effects when predicting effects of parasites on community structure in general and biological invasions in particular.

Intraguild predation enhances biodiversity and functioning in complex food webs

Ecology ◽  
2019 ◽  
Vol 100 (3) ◽  
Author(s):  
Shaopeng Wang ◽  
Ulrich Brose ◽  
Dominique Gravel
Keyword(s):  
Food Webs ◽  
Intraguild Predation

Stochastic structure and nonlinear dynamics of food webs: qualitative stability in a Lotka-Volterra cascade model

1990 ◽  
Vol 240 (1299) ◽  
pp. 607-627 ◽  
Keyword(s):  
Population Dynamics ◽  
Food Webs ◽  
Trophic Structure ◽  
Three Dimensional ◽  
Cascade Model ◽  
Volterra Model ◽  
Critical Surface ◽  
Dimensional Parameter ◽  
Globally Asymptotically Stable ◽  
Number Of Species

Two competing models currently offer to explain empirical regularities observed in food webs. The Lotka-Volterra model describes population dynamics; the cascade model describes trophic structure. In a real ecological community, both population dynamics and trophic structure are important. This paper proposes and analyses a new hybrid model that combines population dynamics and trophic structure: the Lotka-Volterra cascade model (LVCM). The LVCM assumes the population dynamics of the Lotka-Volterra model when the interactions between species are shaped by a refinement of the cascade model. A critical surface divides the three-dimensional parameter space of the LVCM into two regions. In one region, as the number of species becomes large, the limiting probability that the LVCM is qualitatively globally asymptotically stable is positive. In the region on the other side of the critical surface, and on the critical surface itself, this limiting probability is zero. Thus the LVCM displays an ecological phase transition: gradual changes in the probabilities of various kinds of population dynamical interactions related to feeding can have sharp effects on a community’s qualitative stability. The LVCM shows that an inverse proportionality between connectance and the number of species, and a direct proportionality between the number of links and the number of species, as observed in data on food webs, need not be directly connected with the qualitative global asymptotic stability or instability of population dynamics. Empirical testing of the LVCM will require field data on the population dynamical effects of feeding relations.

Sign in / Sign up

Export Citation Format

Share Document