Commercial eel fishers decline in number
... impossible to sell. Joern Larsen, another eel fisher in Mosede Haven, is convinced that if something is not done about the menace there will soon be no coastal fishery left in Denmark. According to Mr Skalkam killing the seals should be permitted if they enter the nets. The short term of the license ...
... impossible to sell. Joern Larsen, another eel fisher in Mosede Haven, is convinced that if something is not done about the menace there will soon be no coastal fishery left in Denmark. According to Mr Skalkam killing the seals should be permitted if they enter the nets. The short term of the license ...
Annex C
... Lyons 2012; Parker 1982). Studies of closely related species inhabiting tropical areas suggest that growth rates are likely to be high. However, like closely related species, L. albertisii probably only reproduces every second year (Madsen and Shine, 2000). For this reason we follow a precautionary ...
... Lyons 2012; Parker 1982). Studies of closely related species inhabiting tropical areas suggest that growth rates are likely to be high. However, like closely related species, L. albertisii probably only reproduces every second year (Madsen and Shine, 2000). For this reason we follow a precautionary ...
Phytobenthic communities in the Baltic Sea succession
... Succession is the sequence of changes in the biota that occur after disturbance (Connell and Slayter 1977). Originally, succession referred to an orderly and directional development of communities on space freed by disturbance where each successive stage is dependent on the former, as described by C ...
... Succession is the sequence of changes in the biota that occur after disturbance (Connell and Slayter 1977). Originally, succession referred to an orderly and directional development of communities on space freed by disturbance where each successive stage is dependent on the former, as described by C ...
A Scientific Review of the Potential Environmental
... whether these changes have effects on fitness in laboratory and natural environments. Long-term effects of interactions between domestic and wild strains will primarily arise from genetic effects, but the phenotype of domestic strains relative to wild strains arises from both genetic and environment ...
... whether these changes have effects on fitness in laboratory and natural environments. Long-term effects of interactions between domestic and wild strains will primarily arise from genetic effects, but the phenotype of domestic strains relative to wild strains arises from both genetic and environment ...
Rating Risk in Pacific Fisheries Workshop March 30
... Final Risk Scoring & Monitoring Levels 1. Final Score is based on the Preliminary Risk score which considered the variable of HIGHEST Consequence x its likelihood 2. Final Score considers Resource Management Considerations that may lead to an override Rating Risk in Pacific Fisheries Workshop March ...
... Final Risk Scoring & Monitoring Levels 1. Final Score is based on the Preliminary Risk score which considered the variable of HIGHEST Consequence x its likelihood 2. Final Score considers Resource Management Considerations that may lead to an override Rating Risk in Pacific Fisheries Workshop March ...
Management Plan for the Banded Killifish
... barriers to migration as the primary threats and limiting factors for this species in Newfoundland. Additional potential threats include development activities such as road development, mineral exploration and urban/cabin development. Additional issues, such as water temperature and availability of ...
... barriers to migration as the primary threats and limiting factors for this species in Newfoundland. Additional potential threats include development activities such as road development, mineral exploration and urban/cabin development. Additional issues, such as water temperature and availability of ...
Predator-induced life-history changes and the coexistence of
... remain genetically distinct, but the co-occurrence with their interspecific hybrids allows the transfer of genes from one taxon to the other. This process increases the number of genotypes and as a consequence the abilities of the parental species to react to changing environmental conditions (Ander ...
... remain genetically distinct, but the co-occurrence with their interspecific hybrids allows the transfer of genes from one taxon to the other. This process increases the number of genotypes and as a consequence the abilities of the parental species to react to changing environmental conditions (Ander ...
Availability of Drift Materials and the Covering Response of the Sea
... sweeps, each of 5-second duration. Each collection was made at sites where I had previously taken 20-urchin samples of covering material. The sweep collections were taken directly on or above these sites in order to collect debris that would actually be available to the same urchins that I had sampl ...
... sweeps, each of 5-second duration. Each collection was made at sites where I had previously taken 20-urchin samples of covering material. The sweep collections were taken directly on or above these sites in order to collect debris that would actually be available to the same urchins that I had sampl ...
Biodiversity and ecosystem functioning in angiosperm
... The aim of this thesis was to investigate how aquatic plant species richness and identity affect ecosystem functioning in terms of processes such as primary production, nutrient availability, epifaunal colonization and properties e.g. stability of Zostera marina subjected to shading. The main work w ...
... The aim of this thesis was to investigate how aquatic plant species richness and identity affect ecosystem functioning in terms of processes such as primary production, nutrient availability, epifaunal colonization and properties e.g. stability of Zostera marina subjected to shading. The main work w ...
SHELLFISH AQUACULTURE - In Praise of Sustainable Economies
... growers!!), and an increased food supply for other organisms. Shellfish culture additionally can reduce the negative impacts from bottom disturbance that would occur if the area had been used instead for harvest of wild stocks. The increased density on shellfish farms means less environmental impact ...
... growers!!), and an increased food supply for other organisms. Shellfish culture additionally can reduce the negative impacts from bottom disturbance that would occur if the area had been used instead for harvest of wild stocks. The increased density on shellfish farms means less environmental impact ...
Coexistence of two stage-structured intraguild predators
... only possible when omnivores were ‘punished’ with lower combined maximum intake rates compared to specialized predators or consumers. In essence, coexistence was only possible if both species were a priori set to be more efficient as either a predator or a consumer. When omnivores profited from feedin ...
... only possible when omnivores were ‘punished’ with lower combined maximum intake rates compared to specialized predators or consumers. In essence, coexistence was only possible if both species were a priori set to be more efficient as either a predator or a consumer. When omnivores profited from feedin ...
ALTERNATIVE PREY AND THE DYNAMICS OF INTRAGUILD
... instability domain. Thus the impact of alternative prey on stability depends upon the reciprocity of the interaction between IG predator and IG prey. Some other scenarios are shown in the electronic appendices. Fig. A1 (in Appendix A) shows a slice through parameter space, where what varies is the I ...
... instability domain. Thus the impact of alternative prey on stability depends upon the reciprocity of the interaction between IG predator and IG prey. Some other scenarios are shown in the electronic appendices. Fig. A1 (in Appendix A) shows a slice through parameter space, where what varies is the I ...
INVASION DYNAMICS OF CYTISUS SCOPARIUS: A MATRIX
... community. Not just the final magnitude of density, but also the form of population response to density can be important; for example, it has been suggested that invasive weeds may experience early inverse density dependence, creating a positive feedback loop that allows population numbers to grow v ...
... community. Not just the final magnitude of density, but also the form of population response to density can be important; for example, it has been suggested that invasive weeds may experience early inverse density dependence, creating a positive feedback loop that allows population numbers to grow v ...
Heritage 386 D.C. FOR
... The extreme modifications of the structure, hydraulics, and hydrology of the estuary is the dominant reason behind the decline of all of these species.' Loss of spawning habitat, nursery habitat and the safety of migratory pathways are the primary factors causing the declines of most species of the ...
... The extreme modifications of the structure, hydraulics, and hydrology of the estuary is the dominant reason behind the decline of all of these species.' Loss of spawning habitat, nursery habitat and the safety of migratory pathways are the primary factors causing the declines of most species of the ...
Management & Engineering Model of Assessment
... Investment climate is a conception which contains comprehensive implication. Factor that influence investment decisions can be divided into two categories: hard climate and soft climate. Investment in physical form “hard” climate and investment in material form “soft” climate. Transportation, posts ...
... Investment climate is a conception which contains comprehensive implication. Factor that influence investment decisions can be divided into two categories: hard climate and soft climate. Investment in physical form “hard” climate and investment in material form “soft” climate. Transportation, posts ...
File
... -May carry parasites and diseases transmissible to native fishes (infection of endangered species) - High potential to affect aquatic communities by reducing populations of native mussels and snails, which eat algae, thereby increasing algae in the system and decreasing water quality - Lifespan of o ...
... -May carry parasites and diseases transmissible to native fishes (infection of endangered species) - High potential to affect aquatic communities by reducing populations of native mussels and snails, which eat algae, thereby increasing algae in the system and decreasing water quality - Lifespan of o ...
BIODIVERSITY AND CONSERVATION
... BIODIVERSITY IS A SOURCE OF RENEWABLE RESOURCES • FOOD • 175 FOODS, 52 BEVERAGES OF FOREST ORIGIN • 90% DOMESTICATED PLANTS HAVE ORIGIN IN THE TROPIC FORESTS • OF 250 K PLANTS 20 K HAVE BEEN FOOD FOR HUMANS ...
... BIODIVERSITY IS A SOURCE OF RENEWABLE RESOURCES • FOOD • 175 FOODS, 52 BEVERAGES OF FOREST ORIGIN • 90% DOMESTICATED PLANTS HAVE ORIGIN IN THE TROPIC FORESTS • OF 250 K PLANTS 20 K HAVE BEEN FOOD FOR HUMANS ...
Root competition can cause a decline in diversity with increased
... separate plots, one for each species. To characterize the community with no competition, each species was grown in monoculture, in a plot in which roots from outside the plot were excluded by trenching and shoots from outside the plot were held back with nets (Fig. 1, left). In the community with on ...
... separate plots, one for each species. To characterize the community with no competition, each species was grown in monoculture, in a plot in which roots from outside the plot were excluded by trenching and shoots from outside the plot were held back with nets (Fig. 1, left). In the community with on ...
Ecosystem Impact of the Decline of Large Whales in the North Pacific
... Combining individual whale prey biomass consumption values with population estimates, we calculated the average daily prey biomass required to sustain the North Pacific populations of large whales before and after their declines from exploitation (Table 16.4). These numbers have uncertainties relate ...
... Combining individual whale prey biomass consumption values with population estimates, we calculated the average daily prey biomass required to sustain the North Pacific populations of large whales before and after their declines from exploitation (Table 16.4). These numbers have uncertainties relate ...
Asymmetrical food web responses in trophic
... 2006). If sustained, increases in variability for a given trophic level will reduce our ability to predict its dynamics. Subsequent transmission of this variability throughout the food web may result in altered dynamics for the entire ecosystem (Carpenter 1988). We test for increased variability of ...
... 2006). If sustained, increases in variability for a given trophic level will reduce our ability to predict its dynamics. Subsequent transmission of this variability throughout the food web may result in altered dynamics for the entire ecosystem (Carpenter 1988). We test for increased variability of ...
Feeding selectivity of the herbivorous fish Scartichthys viridis: effects
... calcareous macroalgae. It follows that, if their numerical abundance in these habitats were also found to be high, their marked feeding selectivity could be an indication of them having a major role in determining macroalgal community structural patterns. Therefore, there is an essential need to inv ...
... calcareous macroalgae. It follows that, if their numerical abundance in these habitats were also found to be high, their marked feeding selectivity could be an indication of them having a major role in determining macroalgal community structural patterns. Therefore, there is an essential need to inv ...
Top-down and bottom-up diversity cascades in detrital vs. living food
... bottom-up and top-down cascades examined in previous studies, but we examine diversity rather than biomass at each consumer trophic level and treat the model system as a mesocosm that contains two unique, interacting communities – the living and detrital food webs. The first hypothesis tested was on ...
... bottom-up and top-down cascades examined in previous studies, but we examine diversity rather than biomass at each consumer trophic level and treat the model system as a mesocosm that contains two unique, interacting communities – the living and detrital food webs. The first hypothesis tested was on ...
Spatial and Temporal Dimensions of Biodiversity Dynamics
... By the early eighteenth century, the phenomenon of directional change in vegetation composition over the years was raising scientific interest, and in 1806 the term ‘succession’ was introduced in its present meaning. Succession goes along with notable diversity changes and is thus an important natur ...
... By the early eighteenth century, the phenomenon of directional change in vegetation composition over the years was raising scientific interest, and in 1806 the term ‘succession’ was introduced in its present meaning. Succession goes along with notable diversity changes and is thus an important natur ...
Propagule supply controls grazer community structure and primary
... terrestrial plant communities suggest that propagule limitation is widespread and many communities are naturally unsaturated (10–13), although most relevant research has been focused at the population level (14, 15). Populations below carrying capacity can respond to increased propagule supply with ...
... terrestrial plant communities suggest that propagule limitation is widespread and many communities are naturally unsaturated (10–13), although most relevant research has been focused at the population level (14, 15). Populations below carrying capacity can respond to increased propagule supply with ...
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.