Benthic Invertebrate Fauna, Small Streams
... invertebrate taxa have been recorded in a mountain stream on Bougainville Island, Papua New Guinea. Incredibly, there are many headwater invertebrate species that remain undescribed in both isolated and populated regions of the world. With the great diversity of foods available for consumption by in ...
... invertebrate taxa have been recorded in a mountain stream on Bougainville Island, Papua New Guinea. Incredibly, there are many headwater invertebrate species that remain undescribed in both isolated and populated regions of the world. With the great diversity of foods available for consumption by in ...
Consumer Fronts, Global Change, and Runaway Collapse
... has since been coined a trophic cascade (Paine 1980). In response to Hairston et al. (1960), other ecologists questioned the basic premise of population stability (Ehrlich & Birch 1967) and further pointed out that what appears to be an abundant supply of green plant biomass is not necessarily edibl ...
... has since been coined a trophic cascade (Paine 1980). In response to Hairston et al. (1960), other ecologists questioned the basic premise of population stability (Ehrlich & Birch 1967) and further pointed out that what appears to be an abundant supply of green plant biomass is not necessarily edibl ...
Chapter 36 – Communities and Ecosystems
... B. Ecosystems a. Energy flow i. Energy flow and chemical cycling (Fig. 37.14) ii. Trophic structure: producers Æ consumers Æ decomposers (Fig. 37.18) 1. Food chains describe who eats who (Fig. 37.8) 2. Food webs are more realistic than food chains (Fig. 37.9) iii. Energy pyramids: only 10% energy tr ...
... B. Ecosystems a. Energy flow i. Energy flow and chemical cycling (Fig. 37.14) ii. Trophic structure: producers Æ consumers Æ decomposers (Fig. 37.18) 1. Food chains describe who eats who (Fig. 37.8) 2. Food webs are more realistic than food chains (Fig. 37.9) iii. Energy pyramids: only 10% energy tr ...
Aquatic Insect Ecology
... of insects found within a habitat. Any significant change in water temperature, as may result from thermal pollution or climate change, will likely alter the species composition of aquatic insects. Considerable variation in temperature tolerance occurs within the orders of aquatic insects, and so te ...
... of insects found within a habitat. Any significant change in water temperature, as may result from thermal pollution or climate change, will likely alter the species composition of aquatic insects. Considerable variation in temperature tolerance occurs within the orders of aquatic insects, and so te ...
Trophic cascades in Yellowstone: The first 15years after wolf
... bison) numbers increased, possibly due to the increase in available woody plants and herbaceous forage resulting from less competition with elk. Trophic cascades research during the first 15 years after wolf reintroduction indicated substantial initial effects on both plants and animals, but northern ...
... bison) numbers increased, possibly due to the increase in available woody plants and herbaceous forage resulting from less competition with elk. Trophic cascades research during the first 15 years after wolf reintroduction indicated substantial initial effects on both plants and animals, but northern ...
- University of Essex Research Repository
... evidence suggests that these chemicals play an important role in foraging behavior and predator–prey interactions (Breckels et al., 2011; Seymour et al., 2010; Strom et al., 2003a,b; Wolfe et al., 1997). Microzooplankton are major grazers of phytoplankton (Calbet and Landry, 2004; Sherr and Sherr, 1 ...
... evidence suggests that these chemicals play an important role in foraging behavior and predator–prey interactions (Breckels et al., 2011; Seymour et al., 2010; Strom et al., 2003a,b; Wolfe et al., 1997). Microzooplankton are major grazers of phytoplankton (Calbet and Landry, 2004; Sherr and Sherr, 1 ...
Lethal interactions among vertebrate top predators
... Lethal interactions among large vertebrate predators have long interested researchers because of ecological and conservation issues. Research focusing on lethal interactions among vertebrate top predators has used several terms with a broad sense, and also introduced new terminology. We analysed the ...
... Lethal interactions among large vertebrate predators have long interested researchers because of ecological and conservation issues. Research focusing on lethal interactions among vertebrate top predators has used several terms with a broad sense, and also introduced new terminology. We analysed the ...
Grassland Ecosystems Black-footed Ferrets
... The black-footed ferret (Mustela nigripes) is the only ferret species native to North America. Historically, they inhabited the Great Plains of the United States, Canada, and Mexico. They are highly dependent on the black-tailed prairie dog for food and for the use of their burrows, in which the fer ...
... The black-footed ferret (Mustela nigripes) is the only ferret species native to North America. Historically, they inhabited the Great Plains of the United States, Canada, and Mexico. They are highly dependent on the black-tailed prairie dog for food and for the use of their burrows, in which the fer ...
Srivastava and Bell 2009
... Species loss has been predicted to have profound effects on the structure and functioning of food webs (Hooper et al. 2005). Recent meta-analyses show that reductions of diversity within a trophic level generally reduce the standing stock of and resource capture by the manipulated trophic level (Bal ...
... Species loss has been predicted to have profound effects on the structure and functioning of food webs (Hooper et al. 2005). Recent meta-analyses show that reductions of diversity within a trophic level generally reduce the standing stock of and resource capture by the manipulated trophic level (Bal ...
Feeding Spectrum and Trophic Relationships of Short
... the amphipods that were identified, the larvae of Gammaridae with their unsegmented cephalothorax were readily counted and they predominated in the food mass (96% occurrence). The average number of gammarid larvae was 137 in the stomachs containing amphipods, the maximum number being 240 in a single ...
... the amphipods that were identified, the larvae of Gammaridae with their unsegmented cephalothorax were readily counted and they predominated in the food mass (96% occurrence). The average number of gammarid larvae was 137 in the stomachs containing amphipods, the maximum number being 240 in a single ...
The Biology of Lakes and Ponds
... ecological theory. From broad ecosystem-level concepts such as trophic structure and trophic dynamics (Elton 1927, Lindeman 1942, Hutchinson 1948), the trophic cascade (Zaret and Paine 1973, Carpenter et al. 1985), and ecological stoichiometry (Tilman 1982, Sterner and Elser 2002), to the impacts of ...
... ecological theory. From broad ecosystem-level concepts such as trophic structure and trophic dynamics (Elton 1927, Lindeman 1942, Hutchinson 1948), the trophic cascade (Zaret and Paine 1973, Carpenter et al. 1985), and ecological stoichiometry (Tilman 1982, Sterner and Elser 2002), to the impacts of ...
Is science in danger of sanctifying the wolf?
... to the point where years ago they reached official biological recovery levels (USFWS, 2011a,b). Along with their recovery came numerous studies of wolf ecology and reported effects of wolves on ecosystems, not only in Yellowstone but in other parks as well, where wolves had also been recovering. Wolv ...
... to the point where years ago they reached official biological recovery levels (USFWS, 2011a,b). Along with their recovery came numerous studies of wolf ecology and reported effects of wolves on ecosystems, not only in Yellowstone but in other parks as well, where wolves had also been recovering. Wolv ...
Is science in danger of sanctifying the wolf?
... to the point where years ago they reached official biological recovery levels (USFWS, 2011a,b). Along with their recovery came numerous studies of wolf ecology and reported effects of wolves on ecosystems, not only in Yellowstone but in other parks as well, where wolves had also been recovering. Wolv ...
... to the point where years ago they reached official biological recovery levels (USFWS, 2011a,b). Along with their recovery came numerous studies of wolf ecology and reported effects of wolves on ecosystems, not only in Yellowstone but in other parks as well, where wolves had also been recovering. Wolv ...
Lourenco_with_editor_changes - DIGITAL.CSIC, el repositorio
... variation in their context and how terms have been applied, but also to the introduction of additional ...
... variation in their context and how terms have been applied, but also to the introduction of additional ...
To Build an Ecosystem
... [a great exam question] Humans can occupy different trophic levels, and different amounts of energy are available to us at each level. The more energy that is available, the larger the human population that could be supported. [Energy content is not the only consideration though. We need protein to ...
... [a great exam question] Humans can occupy different trophic levels, and different amounts of energy are available to us at each level. The more energy that is available, the larger the human population that could be supported. [Energy content is not the only consideration though. We need protein to ...
Do small mammals prey upon an invasive ectoparasite of cervids?
... early summer and were kept in the laboratory for 4–6 weeks. Wild bank voles were captured from the Konnevesi area on previous days and they had been in cages for 1–2 days before our experiment. For the experiment, we placed the voles one by one into similar cages as those used in the other treatment ...
... early summer and were kept in the laboratory for 4–6 weeks. Wild bank voles were captured from the Konnevesi area on previous days and they had been in cages for 1–2 days before our experiment. For the experiment, we placed the voles one by one into similar cages as those used in the other treatment ...
Interactions of multiple predators with different foraging modes in an
... Witman 2004; Schmitz 2007). Predators that have complementary foraging activities facilitate capture success and increase predator growth rates (Soluk 1993; Soluk and Richardson 1997; Losey and Denno 1998; Eklov and VanKooten 2001). Conflicting foraging activities and intraguild predation create int ...
... Witman 2004; Schmitz 2007). Predators that have complementary foraging activities facilitate capture success and increase predator growth rates (Soluk 1993; Soluk and Richardson 1997; Losey and Denno 1998; Eklov and VanKooten 2001). Conflicting foraging activities and intraguild predation create int ...
Marco-Mendez, C., L. M. Ferrero-Vicente, P. Prado, K. L. Heck, J
... such as plant availability and accessibility, plant nutritional quality, human pressure on herbivore populations, and herbivore recruitment and predation risk have all been shown to influence the intensity of herbivory on seagrasses meadows (Prado et al., 2008a, 2009, 2010). In addition, it has been ...
... such as plant availability and accessibility, plant nutritional quality, human pressure on herbivore populations, and herbivore recruitment and predation risk have all been shown to influence the intensity of herbivory on seagrasses meadows (Prado et al., 2008a, 2009, 2010). In addition, it has been ...
Coupled Oscillations in Food Webs: Balancing Competition and
... context of food webs (e.g., apparent competition [Holt 1977], indirect mutualism [Vandermeer 1980], or trophic cascades [Carpenter et al. 1987]). Most recently, there has been a great deal of activity aimed at understanding food web dynamics in the context of the theoretical constructs normally asso ...
... context of food webs (e.g., apparent competition [Holt 1977], indirect mutualism [Vandermeer 1980], or trophic cascades [Carpenter et al. 1987]). Most recently, there has been a great deal of activity aimed at understanding food web dynamics in the context of the theoretical constructs normally asso ...
Ecosystem Services: From Biodiversity to Society, Part 1
... Ecosystem services (ES) are the natural functions and processes of ecosystems which are of value to humans. By definition, therefore, ES are an anthropocentric concept: humans are the focus of ES (Fig. 1). This means that it is essential to acknowledge the social, economic and ecological systems wit ...
... Ecosystem services (ES) are the natural functions and processes of ecosystems which are of value to humans. By definition, therefore, ES are an anthropocentric concept: humans are the focus of ES (Fig. 1). This means that it is essential to acknowledge the social, economic and ecological systems wit ...
Kreb01.pdf
... 40% of the grey willow—the dominant shrub in the area— was consumed, thus indicating that food was not limiting at any time in the cycle. If the absolute abundance of food were limiting, we should have found hares that had starved, but only about 3% of the hare mortalities could be directly attribut ...
... 40% of the grey willow—the dominant shrub in the area— was consumed, thus indicating that food was not limiting at any time in the cycle. If the absolute abundance of food were limiting, we should have found hares that had starved, but only about 3% of the hare mortalities could be directly attribut ...
Changes in the diet of hake associated with El Niño 1997?1998 in
... with a strong inverse relationship between both variables. With this consideration, in the subsequent analyses, the SSTA was used to explore the association between the physical habitat variability and the changes in the diet of hake (Fig. 4a). Although anchovy is the dominant prey of the analysed s ...
... with a strong inverse relationship between both variables. With this consideration, in the subsequent analyses, the SSTA was used to explore the association between the physical habitat variability and the changes in the diet of hake (Fig. 4a). Although anchovy is the dominant prey of the analysed s ...
Ecological Role of Vertebrate Scavengers
... beginning to appreciate the complexity of energy recycling via scavenging pathways and the cascadilllJ impacts anthropogenic activities can have on the disruption of these processes. This chapter highlights the growing body of evidence supporting the importance ofscavenging-derivcd nutrients to a mu ...
... beginning to appreciate the complexity of energy recycling via scavenging pathways and the cascadilllJ impacts anthropogenic activities can have on the disruption of these processes. This chapter highlights the growing body of evidence supporting the importance ofscavenging-derivcd nutrients to a mu ...
Document
... determined by the interplay between immigration and emigration, drift, recruitment, mortality as well as predator-prey interactions. By incorporating various community information an ecosystem model emerges which not only gives a qualitative image, but also quantitative information on the system as ...
... determined by the interplay between immigration and emigration, drift, recruitment, mortality as well as predator-prey interactions. By incorporating various community information an ecosystem model emerges which not only gives a qualitative image, but also quantitative information on the system as ...
Food web
A food web (or food cycle) is the natural interconnection of food chains and generally a graphical representation (usually an image) of what-eats-what in an ecological community. Another name for food web is a consumer-resource system. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs. To maintain their bodies, grow, develop, and to reproduce, autotrophs produce organic matter from inorganic substances, including both minerals and gases such as carbon dioxide. These chemical reactions require energy, which mainly comes from the sun and largely by photosynthesis, although a very small amount comes from hydrothermal vents and hot springs. A gradient exists between trophic levels running from complete autotrophs that obtain their sole source of carbon from the atmosphere, to mixotrophs (such as carnivorous plants) that are autotrophic organisms that partially obtain organic matter from sources other than the atmosphere, and complete heterotrophs that must feed to obtain organic matter. The linkages in a food web illustrate the feeding pathways, such as where heterotrophs obtain organic matter by feeding on autotrophs and other heterotrophs. The food web is a simplified illustration of the various methods of feeding that links an ecosystem into a unified system of exchange. There are different kinds of feeding relations that can be roughly divided into herbivory, carnivory, scavenging and parasitism. Some of the organic matter eaten by heterotrophs, such as sugars, provides energy. Autotrophs and heterotrophs come in all sizes, from microscopic to many tonnes - from cyanobacteria to giant redwoods, and from viruses and bdellovibrio to blue whales.Charles Elton pioneered the concept of food cycles, food chains, and food size in his classical 1927 book ""Animal Ecology""; Elton's 'food cycle' was replaced by 'food web' in a subsequent ecological text. Elton organized species into functional groups, which was the basis for Raymond Lindeman's classic and landmark paper in 1942 on trophic dynamics. Lindeman emphasized the important role of decomposer organisms in a trophic system of classification. The notion of a food web has a historical foothold in the writings of Charles Darwin and his terminology, including an ""entangled bank"", ""web of life"", ""web of complex relations"", and in reference to the decomposition actions of earthworms he talked about ""the continued movement of the particles of earth"". Even earlier, in 1768 John Bruckner described nature as ""one continued web of life"".Food webs are limited representations of real ecosystems as they necessarily aggregate many species into trophic species, which are functional groups of species that have the same predators and prey in a food web. Ecologists use these simplifications in quantitative (or mathematical) models of trophic or consumer-resource systems dynamics. Using these models they can measure and test for generalized patterns in the structure of real food web networks. Ecologists have identified non-random properties in the topographic structure of food webs. Published examples that are used in meta analysis are of variable quality with omissions. However, the number of empirical studies on community webs is on the rise and the mathematical treatment of food webs using network theory had identified patterns that are common to all. Scaling laws, for example, predict a relationship between the topology of food web predator-prey linkages and levels of species richness.