carrying capacity: a critique of the concept al~ its usefulness
... This paper is an attempt to clarify what should be meant by the term carrying capacity when applied to ecological issues. An examination of the various definitions <;U1d uses that the term has been put to will be undertaken. Concentrating on animal populations, I will show that many applications of ...
... This paper is an attempt to clarify what should be meant by the term carrying capacity when applied to ecological issues. An examination of the various definitions <;U1d uses that the term has been put to will be undertaken. Concentrating on animal populations, I will show that many applications of ...
Killer Whales and Marine Mammal Trends in The North Pacific—A
... pinnipeds and sea otters declined in sequence throughout the North Pacific is not born out by the evidence. Alternative analyses presented here reveal—contrary to the suggestion of the prey-switching hypothesis—that, in some regions of the North Pacific, pinniped populations have grown substantially ...
... pinnipeds and sea otters declined in sequence throughout the North Pacific is not born out by the evidence. Alternative analyses presented here reveal—contrary to the suggestion of the prey-switching hypothesis—that, in some regions of the North Pacific, pinniped populations have grown substantially ...
Diet of coastal foraging Eurasian otters ( L.) in Pembrokeshire
... breeding sites (Liles 2003a). It is known that otters are widely distributed in Pembrokeshire (Jones and Jones 2004) and preliminary surveys have indicated that otters are utilising coastal areas for foraging and breeding at some locations (Liles 2003a). Accordingly, Pembrokeshire may represent one ...
... breeding sites (Liles 2003a). It is known that otters are widely distributed in Pembrokeshire (Jones and Jones 2004) and preliminary surveys have indicated that otters are utilising coastal areas for foraging and breeding at some locations (Liles 2003a). Accordingly, Pembrokeshire may represent one ...
Effects of seagrass landscape structure, structural complexity and
... was little separation between crustaceans and fishes in principal component space, but sites of high faunal abundance were distinct from sites of low faunal abundance. Sites with consistently high faunal abundance generally were found in western Core and Back Sounds, whereas sites with consistently ...
... was little separation between crustaceans and fishes in principal component space, but sites of high faunal abundance were distinct from sites of low faunal abundance. Sites with consistently high faunal abundance generally were found in western Core and Back Sounds, whereas sites with consistently ...
killer whales and marine mammal trends in the north pacific—a re
... pinnipeds and sea otters declined in sequence throughout the North Pacific is not born out by the evidence. Alternative analyses presented here reveal—contrary to the suggestion of the prey-switching hypothesis—that, in some regions of the North Pacific, pinniped populations have grown substantially ...
... pinnipeds and sea otters declined in sequence throughout the North Pacific is not born out by the evidence. Alternative analyses presented here reveal—contrary to the suggestion of the prey-switching hypothesis—that, in some regions of the North Pacific, pinniped populations have grown substantially ...
Effects of physical disturbance and habitat
... Grime (1977) described disturbance as partial or total destruction of biomass by consumers, pathogens, or physical forces. Pickett & White (1985) have a broader definition where disturbance is “any discrete event in time that disrupts ecosystem, community, or population structure and changes resourc ...
... Grime (1977) described disturbance as partial or total destruction of biomass by consumers, pathogens, or physical forces. Pickett & White (1985) have a broader definition where disturbance is “any discrete event in time that disrupts ecosystem, community, or population structure and changes resourc ...
Trophic ecology of meiofauna: Francisco J.A. Nascimento
... Meiobenthic metazoans differ from macrofauna not only in size but also in a number of biological characteristics (Warwick 1984), such as having direct benthic development with adult dispersion, and often short generation times and continuous reproductive activity. Regarding feeding adaptations they ...
... Meiobenthic metazoans differ from macrofauna not only in size but also in a number of biological characteristics (Warwick 1984), such as having direct benthic development with adult dispersion, and often short generation times and continuous reproductive activity. Regarding feeding adaptations they ...
Appendix 3-3 Snail Jail Report
... Ungulate control involves fencing in areas of particular concern and then eradicating the animals by trapping and hunting. Weed management requires the constant field work of killing invasive species (often using specialized herbicides). Rare plant work requires native population protection from rat ...
... Ungulate control involves fencing in areas of particular concern and then eradicating the animals by trapping and hunting. Weed management requires the constant field work of killing invasive species (often using specialized herbicides). Rare plant work requires native population protection from rat ...
Effects of Enrichment on Simple Aquatic Food Webs.
... Simple models, often based on Lotka-Volterra-like interactions between predator and prey populations, have a long tradition in ecology due to the relatively simple mathematics involved. Such models have been extended to ecosystems to describe trophic-level biomass in food chains of systems at equili ...
... Simple models, often based on Lotka-Volterra-like interactions between predator and prey populations, have a long tradition in ecology due to the relatively simple mathematics involved. Such models have been extended to ecosystems to describe trophic-level biomass in food chains of systems at equili ...
Full-Text PDF
... are being constructed across the world in increasing numbers [11]. In Korea too, nature-like fishways are attracting increasing amounts of attention, and 8 nature-like fishways have been constructed in large rivers since 2010. By regularly monitoring the use of a fishway after its installation, not ...
... are being constructed across the world in increasing numbers [11]. In Korea too, nature-like fishways are attracting increasing amounts of attention, and 8 nature-like fishways have been constructed in large rivers since 2010. By regularly monitoring the use of a fishway after its installation, not ...
Naive Prey versus Nonnative Predators
... The loss of native species is a subject of concern for conservationists and managers worldwide. Fish represent one of the most specios vertebrate groups on the planet (Helfman et al. 1997). Over the last few decades the number of threatened and endangered fish has increased dramatically. The number ...
... The loss of native species is a subject of concern for conservationists and managers worldwide. Fish represent one of the most specios vertebrate groups on the planet (Helfman et al. 1997). Over the last few decades the number of threatened and endangered fish has increased dramatically. The number ...
Lophius in the world: a synthesis on the common features and life
... and geographic isolation, regression and expansion. The emergence of natural barriers as a result of geological changes led to speciation by vicariance or dispersal (Grant and Leslie, 1993). Phylogenies based on morphological characters and allozymes have been used to propose derivations of the Loph ...
... and geographic isolation, regression and expansion. The emergence of natural barriers as a result of geological changes led to speciation by vicariance or dispersal (Grant and Leslie, 1993). Phylogenies based on morphological characters and allozymes have been used to propose derivations of the Loph ...
Impacts of hypoxia on the structure and processes in pelagic
... in ventilatory (and circulatory) efforts. Irrigation of worm burrows in the sediment or ventilation of gill chambers in bivalves may in fact involve apparent oxyregulation in these animals. By keeping oxygen in their body fluids at minimal levels (e.g. Massabuau, 2001) they could minimize the extent ...
... in ventilatory (and circulatory) efforts. Irrigation of worm burrows in the sediment or ventilation of gill chambers in bivalves may in fact involve apparent oxyregulation in these animals. By keeping oxygen in their body fluids at minimal levels (e.g. Massabuau, 2001) they could minimize the extent ...
Individual phenotypic variation reduces interaction strengths in a
... (Fig. 2B and D). Increasing phenotypic mismatch leads to smaller interaction strengths across all levels of variation (Fig. 2A and C). Our results are robust to changes in the underlying assumptions such as incorporating asymmetric trait distributions (Appendix S4), incorporating asymmetric attack r ...
... (Fig. 2B and D). Increasing phenotypic mismatch leads to smaller interaction strengths across all levels of variation (Fig. 2A and C). Our results are robust to changes in the underlying assumptions such as incorporating asymmetric trait distributions (Appendix S4), incorporating asymmetric attack r ...
Invasive grass carp (
... systems (Bettoli et al. 1993, Chilton and Muoneke 1992). They also have potential negative impacts on native amphibians by removing required cover (Murphy et al. 2002). Grass carp predate on, compete with, and deplete the habitat/shelter of benthic invertebrates and, therefore, influence fish specie ...
... systems (Bettoli et al. 1993, Chilton and Muoneke 1992). They also have potential negative impacts on native amphibians by removing required cover (Murphy et al. 2002). Grass carp predate on, compete with, and deplete the habitat/shelter of benthic invertebrates and, therefore, influence fish specie ...
Consumer Fronts, Global Change, and Runaway Collapse
... because consumers at higher trophic levels control herbivore abundance and thus allow plantdominated ecosystems to persist (Hairston et al. 1960). The core tenet of their argument was that, because green plants dominated most natural ecosystems, herbivores must not be food limited, but instead contr ...
... because consumers at higher trophic levels control herbivore abundance and thus allow plantdominated ecosystems to persist (Hairston et al. 1960). The core tenet of their argument was that, because green plants dominated most natural ecosystems, herbivores must not be food limited, but instead contr ...
Hominid-Carnivore Coevolution and Invasion
... species exploiting shared limiting resources. In classic coevolutionary models, populations of sympatric species are seen to diverge in one or more morphological, ecological, or behavioral traits to effect more even partitioning of resources and reduce levels of interspecific competition. Character ...
... species exploiting shared limiting resources. In classic coevolutionary models, populations of sympatric species are seen to diverge in one or more morphological, ecological, or behavioral traits to effect more even partitioning of resources and reduce levels of interspecific competition. Character ...
Experimental evaluation of evolution and coevolution
... (Post et al. 2008). This bidirectionality suggests that ...
... (Post et al. 2008). This bidirectionality suggests that ...
Risk Assessment
... There are at least 29 species in the snakehead (Channidae) family and are found in cold temperate to tropical areas. The cold temperate snakehead, northern snakehead (Channa argus), is found in areas in Russia, China, and Korea. Northern snakehead is highly favoured as a food fish and is commerciall ...
... There are at least 29 species in the snakehead (Channidae) family and are found in cold temperate to tropical areas. The cold temperate snakehead, northern snakehead (Channa argus), is found in areas in Russia, China, and Korea. Northern snakehead is highly favoured as a food fish and is commerciall ...
A Strategy for the Recovery and Management of Cod Stocks in
... cod off eastern Newfoundland, experienced many changes that clearly were not caused by fishing. High fishing mortality, unfavourable environmental conditions and an increase in predation subsequently resulted in a second collapse that has been, for many stocks, more severe and persistent than the fi ...
... cod off eastern Newfoundland, experienced many changes that clearly were not caused by fishing. High fishing mortality, unfavourable environmental conditions and an increase in predation subsequently resulted in a second collapse that has been, for many stocks, more severe and persistent than the fi ...
Ecological Problems With Iowa`s Invasive and Introduced Fishes
... most likely, it isa combination of adaptations that promote the reproduction and dispersal of these species. Stauffer (1984) also proposed that evolution in a competitive environment could preadapt an exotic fish to become established and increase in range. Such a species would, therefore, be a "K" ...
... most likely, it isa combination of adaptations that promote the reproduction and dispersal of these species. Stauffer (1984) also proposed that evolution in a competitive environment could preadapt an exotic fish to become established and increase in range. Such a species would, therefore, be a "K" ...
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.