Tilburg University A paleoeconomic theory of co
... humans, the colonization of early humans, and why human overkill might have caused a mass megafauna extinction (e.g., mammoths) at the end of the Pleistocene (see Gamble 1998; Brook and Bowman 2002; Roberts et al. 2001; Alroy 2001; Choquenot and Bowman 1998, Beck 1996, Smith 1975). And while many hy ...
... humans, the colonization of early humans, and why human overkill might have caused a mass megafauna extinction (e.g., mammoths) at the end of the Pleistocene (see Gamble 1998; Brook and Bowman 2002; Roberts et al. 2001; Alroy 2001; Choquenot and Bowman 1998, Beck 1996, Smith 1975). And while many hy ...
cod on the southern scotian shelf and in the bay of fundy (div. 4x/5y)
... recruitment estimates for the 2006 and 2007 yearclasses are improved over the preceeding two yearclasses, and should result in an increase in stock biomass in the short-term. A yield of 1,450 t in 2009 would be consistent with the target exploitation rate of 16.5%. At this yield, there is a high pro ...
... recruitment estimates for the 2006 and 2007 yearclasses are improved over the preceeding two yearclasses, and should result in an increase in stock biomass in the short-term. A yield of 1,450 t in 2009 would be consistent with the target exploitation rate of 16.5%. At this yield, there is a high pro ...
Biodiversity: an introduction - European Commission
... This process predominantly affects species level diversity, in that it leads to the creation of novel species. Speciation arises via three different ways: geographical isolation, competition, and polyploidy. 1. Geographical isolation results from the division of a population into two or more separat ...
... This process predominantly affects species level diversity, in that it leads to the creation of novel species. Speciation arises via three different ways: geographical isolation, competition, and polyploidy. 1. Geographical isolation results from the division of a population into two or more separat ...
Habitat: Shallow Rocky Reef Species (0
... 2004), particularly for marine ecosystems where many of the world’s fish populations are overexploited and the ecosystems that sustain them are becoming degraded (FAO 2002). Global climate change, the increased rate on nonnative species spread, pollution and the unintended consequences of fishing, s ...
... 2004), particularly for marine ecosystems where many of the world’s fish populations are overexploited and the ecosystems that sustain them are becoming degraded (FAO 2002). Global climate change, the increased rate on nonnative species spread, pollution and the unintended consequences of fishing, s ...
a landscape simulation model for understanding animal
... in the habitat (e.g. , for two resources that occur equally in a habitat, each has a resource-proportion of 0.5). • A patch is the area composed of all adjacent cells sharing a habitat type where the local-scale processes take place. Individuals of a species in one patch (population) interact among ...
... in the habitat (e.g. , for two resources that occur equally in a habitat, each has a resource-proportion of 0.5). • A patch is the area composed of all adjacent cells sharing a habitat type where the local-scale processes take place. Individuals of a species in one patch (population) interact among ...
Cowlitz Fall Chinook - Northwest Power and Conservation Council
... A number of factors are known to affect the likelihood and severity of such interactions, among them the abundance of the hatchery population relative to other populations; the time, size and life stage at which hatchery fish are released; and the quantity and quality of habitat available to the co- ...
... A number of factors are known to affect the likelihood and severity of such interactions, among them the abundance of the hatchery population relative to other populations; the time, size and life stage at which hatchery fish are released; and the quantity and quality of habitat available to the co- ...
1 THEME: BIODIVERSITY 1.1 Introduction
... Through the most powerful human influence, habitat destruction and ill-conceived developments, biodiversity is under threat world-wide. The focus is frequently on the accelerated rate of disappearance of a species in the face of human influence. The fossil record tells us that individual species evo ...
... Through the most powerful human influence, habitat destruction and ill-conceived developments, biodiversity is under threat world-wide. The focus is frequently on the accelerated rate of disappearance of a species in the face of human influence. The fossil record tells us that individual species evo ...
Good Buddies
... ways. A very specific interaction that may occur between the organisms is defined as symbiosis, a close, coevolutionary association between one species (host) and another species (symbiont). Species may interact in a variety of different ways: 1. Amensalism (- , 0) -- in this interaction, one specie ...
... ways. A very specific interaction that may occur between the organisms is defined as symbiosis, a close, coevolutionary association between one species (host) and another species (symbiont). Species may interact in a variety of different ways: 1. Amensalism (- , 0) -- in this interaction, one specie ...
Butterfly Populations - North American Butterfly Association
... different locations where the same food plant grows may be used in certain years depending on growing conditions. These resource variations are buffers in unusual and adverse conditions. Butterfly species experience a complete turnover of individuals between each generation. Each individual butterfl ...
... different locations where the same food plant grows may be used in certain years depending on growing conditions. These resource variations are buffers in unusual and adverse conditions. Butterfly species experience a complete turnover of individuals between each generation. Each individual butterfl ...
Aquatic Biodiversity
... • Ecological restoration projects worldwide • Make conservation financially rewarding ...
... • Ecological restoration projects worldwide • Make conservation financially rewarding ...
Author`s personal copy - Department of Marine and Coastal Sciences
... In Panama, twenty-four 2 × 50 m belt transects were measured and marked along the edge of the mangroves, and the markings left in place for the duration of the study. An additional 11 transects (2 × 40 m, due to restricted space) were established in Utila. Sites were chosen to keep root density as c ...
... In Panama, twenty-four 2 × 50 m belt transects were measured and marked along the edge of the mangroves, and the markings left in place for the duration of the study. An additional 11 transects (2 × 40 m, due to restricted space) were established in Utila. Sites were chosen to keep root density as c ...
16 Ecosystems Out of Balance
... Scientists have documented many instances of the effect of ecosystem disruption due to species removal. Some ecosystems have a keystone species, which if removed, critically disrupts the balance for the ecosystem. One of the bestknown examples of this is the sea otter and the kelp forests. Sea otter ...
... Scientists have documented many instances of the effect of ecosystem disruption due to species removal. Some ecosystems have a keystone species, which if removed, critically disrupts the balance for the ecosystem. One of the bestknown examples of this is the sea otter and the kelp forests. Sea otter ...
Loss of Diversification of fish species in Meerut region: A... to natural fauna Shobhna , Manu varma
... Abstract: The freshwater aquatic biodiversity is depleting alarmingly due to introduction of exotic species, diseases, habitat loss, pollution, overexploitation and other anthropogenic activities. Loss of biodiversity is severe in freshwater ecosystem which represents a meager of 0.1 percent of eart ...
... Abstract: The freshwater aquatic biodiversity is depleting alarmingly due to introduction of exotic species, diseases, habitat loss, pollution, overexploitation and other anthropogenic activities. Loss of biodiversity is severe in freshwater ecosystem which represents a meager of 0.1 percent of eart ...
why the world is green, the waters are blue and food webs in small
... there apparently has not been such a standardization, and we are open to using ‘riacho’, ‘córrego’, ‘arroio’, ‘igarapé’, ‘aimbim’ as the appendage to ‘ecologia’ to describe the this branch of study). The most used and cited model of how streams and rivers function ecologically is the River Continuum ...
... there apparently has not been such a standardization, and we are open to using ‘riacho’, ‘córrego’, ‘arroio’, ‘igarapé’, ‘aimbim’ as the appendage to ‘ecologia’ to describe the this branch of study). The most used and cited model of how streams and rivers function ecologically is the River Continuum ...
Impacts of Pollutants on Beavers and Otters with Implications for
... Beavers have been used to restore wetlands, improve stream dynamics, and reduce flooding (Müller-Schwarze 2011; Gibson and Olden 2014). The most recent estimate on the population size of the North American beaver is 6-12 million (Naiman et al. 1988) and the Eurasian beaver is estimated at 639,000 (H ...
... Beavers have been used to restore wetlands, improve stream dynamics, and reduce flooding (Müller-Schwarze 2011; Gibson and Olden 2014). The most recent estimate on the population size of the North American beaver is 6-12 million (Naiman et al. 1988) and the Eurasian beaver is estimated at 639,000 (H ...
Top-down and bottom-up control of large herbivore populations: a
... may vary spatially and temporally [5, 6]. Moreover, human activities can potentially affect both topdown and bottom-up processes in terrestrial ecosystems. Humans are a keystone species that alters terrestrial ecosystem structure and composition through actions such as setting fires and livestock gr ...
... may vary spatially and temporally [5, 6]. Moreover, human activities can potentially affect both topdown and bottom-up processes in terrestrial ecosystems. Humans are a keystone species that alters terrestrial ecosystem structure and composition through actions such as setting fires and livestock gr ...
Ecosystem Effects of Fishing and Whaling in the North
... Shurin et al. 2002; Worm and Myers 2003). Another important interaction is competitive release, in which formerly suppressed species replace formerly dominant ones that were reduced by fishing (Fogarty and Murawski 1998; Myers and Worm 2003). Although both prey release and competitive release appear ...
... Shurin et al. 2002; Worm and Myers 2003). Another important interaction is competitive release, in which formerly suppressed species replace formerly dominant ones that were reduced by fishing (Fogarty and Murawski 1998; Myers and Worm 2003). Although both prey release and competitive release appear ...
PII: S0020-7519(01) - University of Otago
... is yes, with at least two processes acting to generate associations between species of larval worms. First, since fish often acquire larval worms when they ingest infected prey, it is possible that the long-lived larval worms accumulate inside a fish as it grows. Indeed, there is much evidence that ...
... is yes, with at least two processes acting to generate associations between species of larval worms. First, since fish often acquire larval worms when they ingest infected prey, it is possible that the long-lived larval worms accumulate inside a fish as it grows. Indeed, there is much evidence that ...
Use of Sterile Grass Carp to Control Aquatic Weeds
... Example 3: A 10 acre pond is examined in March and found to have a one acre infestation of water primrose. Because water primrose grows only in shallow water (less than two feet deep), base the stocking rate on the area of the pond less than two feet deep. If two acres of the pond are less than two ...
... Example 3: A 10 acre pond is examined in March and found to have a one acre infestation of water primrose. Because water primrose grows only in shallow water (less than two feet deep), base the stocking rate on the area of the pond less than two feet deep. If two acres of the pond are less than two ...
FLL_CS5draft - Fisheries Conservation Foundation
... to go fishing for many game fish species, even though most of them are not native to the system. Endangered Species in the system still face the danger of going extinct without action from State and Federal wildlife agencies The Colorado River is vastly different than it was before the influence of ...
... to go fishing for many game fish species, even though most of them are not native to the system. Endangered Species in the system still face the danger of going extinct without action from State and Federal wildlife agencies The Colorado River is vastly different than it was before the influence of ...
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.