Section 1 How Organisms Interact in Communities
... to both sides. But most competitive interactions do not involve fighting. In fact, some competing species never encounter one another. They interact only by means of their effects on the abundance of resources. To understand how competition influences the makeup of communities, you must focus on the ...
... to both sides. But most competitive interactions do not involve fighting. In fact, some competing species never encounter one another. They interact only by means of their effects on the abundance of resources. To understand how competition influences the makeup of communities, you must focus on the ...
Status of Otters in Nepal
... of number of threats such as: i) Habitat loss and destruction due to grazing, sand and boulder extraction, illegal exploitation of natural resources, industrial pollution and barrage construction along Indo-Nepal border and large hydroelectric projects. ii) Overfishing in the major rivers with the u ...
... of number of threats such as: i) Habitat loss and destruction due to grazing, sand and boulder extraction, illegal exploitation of natural resources, industrial pollution and barrage construction along Indo-Nepal border and large hydroelectric projects. ii) Overfishing in the major rivers with the u ...
生態學 - 國立臺南大學
... abundance of organisms and the interactions that determine distribution and abundance. (Townsend, Begon and Happer, 2008) • The primitive humans must have been ecologists of sorts – driven by the need to understand where and when their food and their enemies were to be found. (applied ecologists). ...
... abundance of organisms and the interactions that determine distribution and abundance. (Townsend, Begon and Happer, 2008) • The primitive humans must have been ecologists of sorts – driven by the need to understand where and when their food and their enemies were to be found. (applied ecologists). ...
Species richness and evenness respond in a
... richness and evenness are not necessarily the norm, and the ecological causes of these deviations from positive relationships deserve further study. Whether richness or evenness has a larger influence on diversity, and how they might be related to each other, may come down to whether species assembl ...
... richness and evenness are not necessarily the norm, and the ecological causes of these deviations from positive relationships deserve further study. Whether richness or evenness has a larger influence on diversity, and how they might be related to each other, may come down to whether species assembl ...
Size-dependent trait-mediated indirect interactions among sea
... Individual sea urchins and P. helianthoides were only used in one grazing trial, and tanks were cleaned between trials. In the first grazing experiment, I placed a single S. droebachiensis in the downstream compartment of each of the previously described seawater tanks. Seven of these 14 tanks conta ...
... Individual sea urchins and P. helianthoides were only used in one grazing trial, and tanks were cleaned between trials. In the first grazing experiment, I placed a single S. droebachiensis in the downstream compartment of each of the previously described seawater tanks. Seven of these 14 tanks conta ...
The Canadian Seal Hunt: No Management and
... numbering 130,000-140,000. A third population of around 7,500 is found in the Baltic Sea, giving a global total of 290,000300,000. Large-scale commercial hunting has not taken place in recent years, but there have been calls to allow catches in Canada. In addition, this species is involved in freque ...
... numbering 130,000-140,000. A third population of around 7,500 is found in the Baltic Sea, giving a global total of 290,000300,000. Large-scale commercial hunting has not taken place in recent years, but there have been calls to allow catches in Canada. In addition, this species is involved in freque ...
- UTas ePrints - University of Tasmania
... habitats compared with adjacent habitats such as mudflats and seagrass beds, so that assemblages of juvenile fish in mangrove habitats are unique (Thayer et al., 1987; Morton, 1990; Robertson and Duke, 1990; Laegdsgaard and Johnson, 1995). However, while the nursery role of mangroves is well establi ...
... habitats compared with adjacent habitats such as mudflats and seagrass beds, so that assemblages of juvenile fish in mangrove habitats are unique (Thayer et al., 1987; Morton, 1990; Robertson and Duke, 1990; Laegdsgaard and Johnson, 1995). However, while the nursery role of mangroves is well establi ...
Bust economics: foragers choose high quality habitats in
... patches based on their food quality. We asked two questions: (1) Do dunnarts during bust conditions select high quality food patches or forage opportunistically? (2) Is the stronger competitor (larger species) more selective of high quality food patches than the weaker competitor? Bust periods are c ...
... patches based on their food quality. We asked two questions: (1) Do dunnarts during bust conditions select high quality food patches or forage opportunistically? (2) Is the stronger competitor (larger species) more selective of high quality food patches than the weaker competitor? Bust periods are c ...
The understudied and underappreciated role of predation in the
... fisheries and the development of effective management and conservation plans. By far, the most commonly employed means of studying post-release mortality (PRM) is the use of artificial enclosures (tanks and pens; Cooke and Schramm 2007). Research studies evaluating mortality that include long-term m ...
... fisheries and the development of effective management and conservation plans. By far, the most commonly employed means of studying post-release mortality (PRM) is the use of artificial enclosures (tanks and pens; Cooke and Schramm 2007). Research studies evaluating mortality that include long-term m ...
Predators of the destructive sea urchin Strongylocentrotus
... supply is restricted to areas where temperatures during the planktonic phase do not exceed this critical upper limit. Fagerli et al. (2013) studied early recruitment of sea urchins within areas of barren ground in central Norway and found that low recruitment coincided with recent, warmer sea temper ...
... supply is restricted to areas where temperatures during the planktonic phase do not exceed this critical upper limit. Fagerli et al. (2013) studied early recruitment of sea urchins within areas of barren ground in central Norway and found that low recruitment coincided with recent, warmer sea temper ...
modeling the role of primary productivity disruption in end
... END-PERMIAN TERRESTRIAL ECOSYSTEMS A second issue that must be addressed is whether there is evidence of large-scale primary producer disruption in end-Permian terrestrial ecosystems. Even if the effects of primary extinction could cascade through these trophic networks, such a scenario would be unl ...
... END-PERMIAN TERRESTRIAL ECOSYSTEMS A second issue that must be addressed is whether there is evidence of large-scale primary producer disruption in end-Permian terrestrial ecosystems. Even if the effects of primary extinction could cascade through these trophic networks, such a scenario would be unl ...
Population demographics and trade
... 1998; Sakai et al. 2001). Fast growth rates reflect rapid acquisition and allocation of resources, which enable a species to swiftly establish a population following colonization. While life-history theory predicts a trade-off between high reproduction and growth rates (Stearns 1992), research examini ...
... 1998; Sakai et al. 2001). Fast growth rates reflect rapid acquisition and allocation of resources, which enable a species to swiftly establish a population following colonization. While life-history theory predicts a trade-off between high reproduction and growth rates (Stearns 1992), research examini ...
Ansorge, H., Kluth, G., and Hahne, S. (2006). Feeding ecology of
... each of the three ungulate species most abundant in the wolves’ prey. However, the data of Table 1 represents only the minimum number of fawns, calves or piglets, because not all remaining individuals of these species could be definitely determined to be adults. Medium- and small-sized prey items we ...
... each of the three ungulate species most abundant in the wolves’ prey. However, the data of Table 1 represents only the minimum number of fawns, calves or piglets, because not all remaining individuals of these species could be definitely determined to be adults. Medium- and small-sized prey items we ...
Nichols, M.C. 2003. Conservation strategy for robust redhorse
... experienced with survival rates from the post yolk sac larval stage to harvestable juveniles after one or two years. This may be related to nutritional or habitat requirements during this stage. The rate of survival of year 1 fingerlings from eggs of artificially spawned robust redhorse has increase ...
... experienced with survival rates from the post yolk sac larval stage to harvestable juveniles after one or two years. This may be related to nutritional or habitat requirements during this stage. The rate of survival of year 1 fingerlings from eggs of artificially spawned robust redhorse has increase ...
Ecological Balances, Activity Based Foundation Course on
... Societies and individuals are reacting more rapidly to global changes than they ever did before. Changing environmental perspectives in Europe have led to migration of polluting industries into the developing countries. Ten1 ...
... Societies and individuals are reacting more rapidly to global changes than they ever did before. Changing environmental perspectives in Europe have led to migration of polluting industries into the developing countries. Ten1 ...
First record of the common carp Cyprinus carpio
... ponds, lagoons and dams have been stocked with these carp species mainly in rural areas in order to increase protein consumption and generate jobs. Carp have played an important role in aquaculture development in Mexico, occupying in 1985 the second place in importance for yield in freshwater fisher ...
... ponds, lagoons and dams have been stocked with these carp species mainly in rural areas in order to increase protein consumption and generate jobs. Carp have played an important role in aquaculture development in Mexico, occupying in 1985 the second place in importance for yield in freshwater fisher ...
A review of the ecological implications of mariculture and
... Brown et al. (1987) observed that benthic fauna showed marked changes in species number, species diversity, faunal abundance, and biomass in the region of the fish farm and identified four zones of effect: Zone 1 - An azoic zone directly beneath and up to the edge of the cages. Zone 2 - A highly enr ...
... Brown et al. (1987) observed that benthic fauna showed marked changes in species number, species diversity, faunal abundance, and biomass in the region of the fish farm and identified four zones of effect: Zone 1 - An azoic zone directly beneath and up to the edge of the cages. Zone 2 - A highly enr ...
Pleistocene Rewilding - UNM Biology
... of well-known and often interrelated general forms, including habitat alteration and fragmentation, pollution, and resource reductions as a result of exploitation. Large vertebrates (the megafauna) are often the first species to disappear in the wake of these influences because of their inherently l ...
... of well-known and often interrelated general forms, including habitat alteration and fragmentation, pollution, and resource reductions as a result of exploitation. Large vertebrates (the megafauna) are often the first species to disappear in the wake of these influences because of their inherently l ...
COFFEEVILLE LAKE WARRIOR - TOMBIGBEE RIVERS, ALABAMA
... are to be managed to provide the public with the maximum sustained yield of harvestably sizes of sport and commercial species and to insure the continued existence of the miscellaneous species. ...
... are to be managed to provide the public with the maximum sustained yield of harvestably sizes of sport and commercial species and to insure the continued existence of the miscellaneous species. ...
The ecological module of BOATS-1.0
... representations of biological and ecological processes, and is computationally efficient, allowing extensive parameterspace analyses even when implemented globally. As such, it enables the exploration of the linkages between ocean biogeochemistry, climate, and upper trophic levels at the global scal ...
... representations of biological and ecological processes, and is computationally efficient, allowing extensive parameterspace analyses even when implemented globally. As such, it enables the exploration of the linkages between ocean biogeochemistry, climate, and upper trophic levels at the global scal ...
BiomePresentation project
... class in PowerPoint or I Movie. (upload to Mrs. Dunnavant’s school web page) 3. Each student will become familiar with the names and basic characteristics of the different biomes and the populations they contain. ...
... class in PowerPoint or I Movie. (upload to Mrs. Dunnavant’s school web page) 3. Each student will become familiar with the names and basic characteristics of the different biomes and the populations they contain. ...
Ecological Role of Predators - National Wolfwatcher Coalition
... human influences on food webs (Strong and Frank, 2010; Muhly et al., 2011). Large-carnivore extinctions have had strong effects on biodiversity loss at ecosystem (Berger et al., 2001; Terborgh et al., 2001) and global scales (Estes et al., 2011). Yet, the numerical reduction and spatial restriction o ...
... human influences on food webs (Strong and Frank, 2010; Muhly et al., 2011). Large-carnivore extinctions have had strong effects on biodiversity loss at ecosystem (Berger et al., 2001; Terborgh et al., 2001) and global scales (Estes et al., 2011). Yet, the numerical reduction and spatial restriction o ...
NITROGEN LIMITATION AND TROPHIC VS. ABIOTIC INFLUENCES ON M E. R
... Finally, abiotic conditions also may be important for grasshoppers, because years with below-average temperature and/or above-average precipitation can inhibit their productivity. Cool, wet conditions are often associated with retarded development (Scharff 1954, Dempster 1963, Gage and Mukerji 1977, ...
... Finally, abiotic conditions also may be important for grasshoppers, because years with below-average temperature and/or above-average precipitation can inhibit their productivity. Cool, wet conditions are often associated with retarded development (Scharff 1954, Dempster 1963, Gage and Mukerji 1977, ...
species replacement during early secondary succession
... sites (Rothacher et al. 1967, Dyrness 1973, Halpern 1989). Prior to harvest, Starrbright supported mature to old-growth forest dominated by Pseudotsuga menziesii, with Tsuga heterophylla and Thuja plicata common in the lower canopy. Understories were fairly uniform in composition, dominated by the s ...
... sites (Rothacher et al. 1967, Dyrness 1973, Halpern 1989). Prior to harvest, Starrbright supported mature to old-growth forest dominated by Pseudotsuga menziesii, with Tsuga heterophylla and Thuja plicata common in the lower canopy. Understories were fairly uniform in composition, dominated by the s ...
Network ecology: topological constraints on ecosystem dynamics
... webs may be weighted (valued) graphs: for the first, we have many examples (162; 134) showing the material fluxes of mostly carbon, while the second case is much rarer (but see (117) for weighted competition or (77) for weighted mutualism). For many purposes, undirected webs can be considered (trac ...
... webs may be weighted (valued) graphs: for the first, we have many examples (162; 134) showing the material fluxes of mostly carbon, while the second case is much rarer (but see (117) for weighted competition or (77) for weighted mutualism). For many purposes, undirected webs can be considered (trac ...
Overexploitation
Overexploitation, also called overharvesting, refers to harvesting a renewable resource to the point of diminishing returns. Sustained overexploitation can lead to the destruction of the resource. The term applies to natural resources such as: wild medicinal plants, grazing pastures, game animals, fish stocks, forests, and water aquifers.In ecology, overexploitation describes one of the five main activities threatening global biodiversity. Ecologists use the term to describe populations that are harvested at a rate that is unsustainable, given their natural rates of mortality and capacities for reproduction. This can result in extinction at the population level and even extinction of whole species. In conservation biology the term is usually used in the context of human economic activity that involves the taking of biological resources, or organisms, in larger numbers than their populations can withstand. The term is also used and defined somewhat differently in fisheries, hydrology and natural resource management.Overexploitation can lead to resource destruction, including extinctions. However it is also possible for overexploitation to be sustainable, as discussed below in the section on fisheries. In the context of fishing, the term overfishing can be used instead of overexploitation, as can overgrazing in stock management, overlogging in forest management, overdrafting in aquifer management, and endangered species in species monitoring. Overexploitation is not an activity limited to humans. Introduced predators and herbivores, for example, can overexploit native flora and fauna.