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• 41. [Article] Responses of Aquatic Non-Native Species to Novel Predator Cues and Increased Mortality

  Lethal biotic interactions strongly influence the potential for aquatic non-native species to establish and endure in habitats to which they are introduced. Predators in the recipient area, including native ...

  Citation × Citation Citation Abstract Copy Title: Responses of Aquatic Non-Native Species to Novel Predator Cues and Increased Mortality Author: Turner, Brian Christopher Year: 2017 Lethal biotic interactions strongly influence the potential for aquatic non-native species to establish and endure in habitats to which they are introduced. Predators in the recipient area, including native and previously established non-native predators, can prevent establishment, limit habitat use, and reduce abundance of non-native species. Management efforts by humans using methods designed to cause mass mortality (e.g., trapping, biocide applications) can reduce or eradicate non-native populations. However, the impacts of predator and human induced mortality may be mitigated by the behavior or population-level responses of a given non-native species. My dissertation examined the responses of non-native aquatic species to the risk of predation by novel (i.e., no previous exposure) predators in the recipient community and indicators of potential compensatory responses by non-native populations to increased mortality resulting from removal efforts. My dissertation addresses four primary questions. 1) Can first generation, naïve invaders recognize and defend against predators found within the region of invasion through the expression of inducible defenses? 2) Can the overcompensatory potential of a population be predicted though examinations of intraspecific interactions of individuals from the population? 3) What is the relationship between removal effort outcome (i.e., successful or unsuccessful reduction of the target population) and compensatory population responses? 4) Is there a relationship between characteristics of removal efforts that are typically available to managers (e.g., target area size, target area connectivity, removal methodology) and compensatory population responses that could indicate the relative likelihood of compensation resulting from removal efforts? An invading species should be more likely to establish if it can successfully identify and defend against predators in the recipient range, such as through the expression of inducible defenses. Inducible defenses are behavioral or physiological changes that reduce an organism's susceptibility to predation. Through a series of laboratory experiments, I tested whether inducible defenses, in the form of increased burrowing depth, may have benefited the early stage of invasion of Nuttallia obscurata (purple varnish clam), an established Northeast Pacific invader. Specimens of N. obscurata were collected from introduced populations in the Northeast Pacific and from a native population in Japan. The clams were exposed to chemical and physical cues from Northeast Pacific crab predators, including the native Metacarcinus magister (Dungeness crab), an abundant and frequent predator of N. obscurata. While introduced N. obscurata increased their burrowing depth in the physical presence of M. magister, clams collected from their native range showed no such response. This lack of increased burrowing depth by naïve clams in response to a predator native to the newly invaded range, but a significant increase in depth for clams from populations established in the range suggests that while inducible defenses likely did not contribute to the initial establishment of N. obscurata in the Northeast Pacific, they may contribute to their continued persistence and expansion in their introduced range. Some efforts to reduce invasive populations have paradoxically led to population increases. This phenomenon, referred to as overcompensation, occurs when strong negative density-dependent interactions are reduced through increased mortality within a population, resulting in an increase in the population's recruitment rate sufficient to increase the population's overall abundance. Increases in a population's recruitment rate can result from reduced cannibalism of juveniles resulting in lower mortality of new recruits, from increased adult reproductive output, which increases the number of potential recruits, or from reductions in size and/or age at maturity of the unharvested population, which increases the number of reproductive individuals. I predicted the overcompensatory potential of a population of Carcinus maenas (European green crab) in Bodega Harbor, California, using a series of laboratory and field experiments examining intraspecific pressures of adults on juveniles in the population. This measure of intraspecific pressure was used to predict the overcompensatory potential of the population in response to increased mortality from ongoing removal efforts. This prediction was then assessed using pre- and post-removal surveys of juvenile recruitment in Bodega Harbor compared to nearby populations, testing for evidence of overcompensation. While adult C. maenas in Bodega Harbor had limited negative impacts on juveniles, I concluded it was unlikely to result in overcompensation. Relative juvenile abundance did not statistically increase in removal compared to reference populations, consistent with my conclusion from the experiments. Increases in recruitment rates can occur as a result of efforts to remove non-native species. This increase in recruitment can result in overcompensation, but more commonly results in compensation, where recruitment rates increase relative to pre-removal recruitment but does not result in in the population's abundance exceeding pre-removal levels. However, a detailed and accurate prediction of the response of a population to harvest is time consuming and data intensive. This is not feasible for most efforts to eradicate non-native species, which have the greatest chance of success when enacted rapidly after detection. For my final chapter, I performed a literature review and accompanying statistical analysis to determine if typically available information related to the removal effort (site size, site connectivity, and removal technique) could be used to determine increased risk of compensation for a given effort to remove aquatic invasive species. Compensation was closely linked to unsuccessful removal efforts and was observed only among efforts utilizing physical removal methods. However, the frequency with which compensation occurred varied with the exact technique employed, occurring most frequently in removal utilizing electrofishing. Additionally, evidence of compensation was more frequent among larger removal areas with variable connectivity. While other predictors (temperature, effort, etc) might add to the predicative power, the findings of the review provide criteria for managers to determine the relative risk of compensation prior to the start of removal. Further understanding of how invasive species respond to lethal biotic interactions, including anthropogenically mediated control measures, can aid in assessing the risk of invasion for a given species and inform managers of the risk of complications resulting from removal efforts. While inducible defenses may contribute to the long-term success of an introduced species in their recipient range, my findings did not support the idea that inducible defenses triggered by predator cues contributed to their initial introduction in this case. However, research on other non-native species and offspring of previously naïve prey would allow for a clearer picture of the role of inducible defenses in the invasion process. Compensation resulting from removal efforts does not guarantee failure, and certain characteristics of removal efforts seem to indicate increased risk of compensation. Together these components help identify how biotic interactions surrounding mortality risk of an invading species help shape the trajectory of invasion. Title: Responses of Aquatic Non-Native Species to Novel Predator Cues and Increased Mortality Author: Turner, Brian Christopher Year: 2017 Lethal biotic interactions strongly influence the potential for aquatic non-native species to establish and endure in habitats to which they are introduced. Predators in the recipient area, including native and previously established non-native predators, can prevent establishment, limit habitat use, and reduce abundance of non-native species. Management efforts by humans using methods designed to cause mass mortality (e.g., trapping, biocide applications) can reduce or eradicate non-native populations. However, the impacts of predator and human induced mortality may be mitigated by the behavior or population-level responses of a given non-native species. My dissertation examined the responses of non-native aquatic species to the risk of predation by novel (i.e., no previous exposure) predators in the recipient community and indicators of potential compensatory responses by non-native populations to increased mortality resulting from removal efforts. My dissertation addresses four primary questions. 1) Can first generation, naïve invaders recognize and defend against predators found within the region of invasion through the expression of inducible defenses? 2) Can the overcompensatory potential of a population be predicted though examinations of intraspecific interactions of individuals from the population? 3) What is the relationship between removal effort outcome (i.e., successful or unsuccessful reduction of the target population) and compensatory population responses? 4) Is there a relationship between characteristics of removal efforts that are typically available to managers (e.g., target area size, target area connectivity, removal methodology) and compensatory population responses that could indicate the relative likelihood of compensation resulting from removal efforts? An invading species should be more likely to establish if it can successfully identify and defend against predators in the recipient range, such as through the expression of inducible defenses. Inducible defenses are behavioral or physiological changes that reduce an organism's susceptibility to predation. Through a series of laboratory experiments, I tested whether inducible defenses, in the form of increased burrowing depth, may have benefited the early stage of invasion of Nuttallia obscurata (purple varnish clam), an established Northeast Pacific invader. Specimens of N. obscurata were collected from introduced populations in the Northeast Pacific and from a native population in Japan. The clams were exposed to chemical and physical cues from Northeast Pacific crab predators, including the native Metacarcinus magister (Dungeness crab), an abundant and frequent predator of N. obscurata. While introduced N. obscurata increased their burrowing depth in the physical presence of M. magister, clams collected from their native range showed no such response. This lack of increased burrowing depth by naïve clams in response to a predator native to the newly invaded range, but a significant increase in depth for clams from populations established in the range suggests that while inducible defenses likely did not contribute to the initial establishment of N. obscurata in the Northeast Pacific, they may contribute to their continued persistence and expansion in their introduced range. Some efforts to reduce invasive populations have paradoxically led to population increases. This phenomenon, referred to as overcompensation, occurs when strong negative density-dependent interactions are reduced through increased mortality within a population, resulting in an increase in the population's recruitment rate sufficient to increase the population's overall abundance. Increases in a population's recruitment rate can result from reduced cannibalism of juveniles resulting in lower mortality of new recruits, from increased adult reproductive output, which increases the number of potential recruits, or from reductions in size and/or age at maturity of the unharvested population, which increases the number of reproductive individuals. I predicted the overcompensatory potential of a population of Carcinus maenas (European green crab) in Bodega Harbor, California, using a series of laboratory and field experiments examining intraspecific pressures of adults on juveniles in the population. This measure of intraspecific pressure was used to predict the overcompensatory potential of the population in response to increased mortality from ongoing removal efforts. This prediction was then assessed using pre- and post-removal surveys of juvenile recruitment in Bodega Harbor compared to nearby populations, testing for evidence of overcompensation. While adult C. maenas in Bodega Harbor had limited negative impacts on juveniles, I concluded it was unlikely to result in overcompensation. Relative juvenile abundance did not statistically increase in removal compared to reference populations, consistent with my conclusion from the experiments. Increases in recruitment rates can occur as a result of efforts to remove non-native species. This increase in recruitment can result in overcompensation, but more commonly results in compensation, where recruitment rates increase relative to pre-removal recruitment but does not result in in the population's abundance exceeding pre-removal levels. However, a detailed and accurate prediction of the response of a population to harvest is time consuming and data intensive. This is not feasible for most efforts to eradicate non-native species, which have the greatest chance of success when enacted rapidly after detection. For my final chapter, I performed a literature review and accompanying statistical analysis to determine if typically available information related to the removal effort (site size, site connectivity, and removal technique) could be used to determine increased risk of compensation for a given effort to remove aquatic invasive species. Compensation was closely linked to unsuccessful removal efforts and was observed only among efforts utilizing physical removal methods. However, the frequency with which compensation occurred varied with the exact technique employed, occurring most frequently in removal utilizing electrofishing. Additionally, evidence of compensation was more frequent among larger removal areas with variable connectivity. While other predictors (temperature, effort, etc) might add to the predicative power, the findings of the review provide criteria for managers to determine the relative risk of compensation prior to the start of removal. Further understanding of how invasive species respond to lethal biotic interactions, including anthropogenically mediated control measures, can aid in assessing the risk of invasion for a given species and inform managers of the risk of complications resulting from removal efforts. While inducible defenses may contribute to the long-term success of an introduced species in their recipient range, my findings did not support the idea that inducible defenses triggered by predator cues contributed to their initial introduction in this case. However, research on other non-native species and offspring of previously naïve prey would allow for a clearer picture of the role of inducible defenses in the invasion process. Compensation resulting from removal efforts does not guarantee failure, and certain characteristics of removal efforts seem to indicate increased risk of compensation. Together these components help identify how biotic interactions surrounding mortality risk of an invading species help shape the trajectory of invasion. Close

• 42. [Article] Bycatch Risk Pools for the US West Coast Groundfish Fishery

  Abstract only

  Citation × Citation Citation Abstract Copy Title: Bycatch Risk Pools for the US West Coast Groundfish Fishery Author: Jannot, Jason, Holland, Daniel Abstract only Title: Bycatch Risk Pools for the US West Coast Groundfish Fishery Author: Jannot, Jason, Holland, Daniel Abstract only Close

• 43. [Article] Habitat quality and assessing risks to avian biodiversity

  Models that assess the risk to biodiversity from landscape change can help communities prioritize planning decisions. Accurate representation of the ecology and life history traits of species is necessary. ...

  Citation × Citation Citation Abstract Copy Title: Habitat quality and assessing risks to avian biodiversity Author: Barczak, Mary J. Models that assess the risk to biodiversity from landscape change can help communities prioritize planning decisions. Accurate representation of the ecology and life history traits of species is necessary. This study introduces the use of habitat quality in a biodiversity risk model to determine the significance of habitat quality when predicting risks to biodiversity due to landscape change. The difference between residential and forest habitats in terms of habitat quality for breeding birds was used to test the significance of habitat quality to the risk model. Relative habitat quality was estimated from population densities for 62 bird species associated with both forest and residential habitats. The effect of habitat quality was tested using two possible future landscapes: Buildout and Spine. Predicted risk for the 62 bird species due to landscape change increased by 74% in the Buildout Landscape and 31% in the Spine Landscape when habitat quality was considered. The life history traits of species most at risk were compared to the traits of species that benefited from the landscape change. Life history traits considered included foraging strategy, nest type and placement, migratory status, and area sensitivity. Species at high risk included ground nesters, foliage and tree trunk gleaners, neotropical migrants, and area sensitive species. Title: Habitat quality and assessing risks to avian biodiversity Author: Barczak, Mary J. Models that assess the risk to biodiversity from landscape change can help communities prioritize planning decisions. Accurate representation of the ecology and life history traits of species is necessary. This study introduces the use of habitat quality in a biodiversity risk model to determine the significance of habitat quality when predicting risks to biodiversity due to landscape change. The difference between residential and forest habitats in terms of habitat quality for breeding birds was used to test the significance of habitat quality to the risk model. Relative habitat quality was estimated from population densities for 62 bird species associated with both forest and residential habitats. The effect of habitat quality was tested using two possible future landscapes: Buildout and Spine. Predicted risk for the 62 bird species due to landscape change increased by 74% in the Buildout Landscape and 31% in the Spine Landscape when habitat quality was considered. The life history traits of species most at risk were compared to the traits of species that benefited from the landscape change. Life history traits considered included foraging strategy, nest type and placement, migratory status, and area sensitivity. Species at high risk included ground nesters, foliage and tree trunk gleaners, neotropical migrants, and area sensitive species. Close

• 44. [Article] Evolving Bycatch Risk in the Pacific Groundfish Trawl IFQ

  Catches of several potential choke species in the Pacific groundfish IFQ are highly uncertain and tend to be concentrated while quota is broadly distributed. An analysis prior to implementation of the ...

  Citation × Citation Citation Abstract Copy Title: Evolving Bycatch Risk in the Pacific Groundfish Trawl IFQ Author: Holland, Dan Catches of several potential choke species in the Pacific groundfish IFQ are highly uncertain and tend to be concentrated while quota is broadly distributed. An analysis prior to implementation of the IFQ suggested substantial risk of individual vessels accidentally exceeding quota allocations for several rockfish species and Pacific halibut. Many fishermen lacked confidence that they would be able to acquire quota on the market to cover incidental catch and consequently joined risk pools to mitigate this risk. I update the analysis of bycatch risk using tow level catch data since implementation of the IFQ. The analysis indicates that expected catch rates of most choke species have declined suggesting more effective bycatch avoidance behavior. However, there remains a significant risk that vessels’ catch of some choke species can be several times median quota allocations, in part because many vessels have increased catch and effort by leasing quota pounds, but quota share ownership has remained distributed. The results underscore the importance of an efficient quota market to redistribute quota to match realized catches, but a recent analysis suggests that the quota market is not distributing quota effectively and is subject to high transactions costs.  This provides and explanation for the persistence of risk pools despite the fact that aggregate catches of overfished rockfish species and Pacific halibut have remained well below total quotas.   Title: Evolving Bycatch Risk in the Pacific Groundfish Trawl IFQ Author: Holland, Dan Catches of several potential choke species in the Pacific groundfish IFQ are highly uncertain and tend to be concentrated while quota is broadly distributed. An analysis prior to implementation of the IFQ suggested substantial risk of individual vessels accidentally exceeding quota allocations for several rockfish species and Pacific halibut. Many fishermen lacked confidence that they would be able to acquire quota on the market to cover incidental catch and consequently joined risk pools to mitigate this risk. I update the analysis of bycatch risk using tow level catch data since implementation of the IFQ. The analysis indicates that expected catch rates of most choke species have declined suggesting more effective bycatch avoidance behavior. However, there remains a significant risk that vessels’ catch of some choke species can be several times median quota allocations, in part because many vessels have increased catch and effort by leasing quota pounds, but quota share ownership has remained distributed. The results underscore the importance of an efficient quota market to redistribute quota to match realized catches, but a recent analysis suggests that the quota market is not distributing quota effectively and is subject to high transactions costs.  This provides and explanation for the persistence of risk pools despite the fact that aggregate catches of overfished rockfish species and Pacific halibut have remained well below total quotas.   Close

• 45. [Article] Balancing Efficiency and Risk with Flexible Catch Balancing Policies

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Balancing Efficiency and Risk with Flexible Catch Balancing Policies Author: Herrera, Guillermo E., Holland, Dan Research Paper Title: Balancing Efficiency and Risk with Flexible Catch Balancing Policies Author: Herrera, Guillermo E., Holland, Dan Research Paper Close

• 46. [Article] Perceptions of ecological risk from natural hazards

  38 pages

  Citation × Citation Citation Abstract Copy Title: Perceptions of ecological risk from natural hazards Author: Axelrod, Lawrence J., McDaniels, Timothy, Slovic, Paul Year: 2017, 1999 38 pages Title: Perceptions of ecological risk from natural hazards Author: Axelrod, Lawrence J., McDaniels, Timothy, Slovic, Paul Year: 2017, 1999 38 pages Close

• 47. [Article] Divergent anti-predator strategies and risk allocation in juveniles of three North Pacific flatfishes

  Frequent or lengthy predation risk can cause one of two modifications of prey feeding behavior: 1) postponement of feeding to less risky periods, or 2) resumption of feeding behavior despite persistent ...

  Citation × Citation Citation Abstract Copy Title: Divergent anti-predator strategies and risk allocation in juveniles of three North Pacific flatfishes Author: Boersma, Kate S. Frequent or lengthy predation risk can cause one of two modifications of prey feeding behavior: 1) postponement of feeding to less risky periods, or 2) resumption of feeding behavior despite persistent risk. North Pacific flatfishes exhibit both of these responses when confronted with temporal variation in risk, and this experimental series demonstrates that the particular response reflects species-specific behavioral strategies. Two laboratory experiments were conducted with juvenile English sole (Parophrys vetulus), northern rock sole (Lepidopsetta polyxystra), and Pacific halibut (Hippoglossus stenolepis), which inhabit the same nurseries in Alaska as juveniles but have been shown to exhibit different levels of risk aversion. One experiment explored the effects of variation in risk exposure frequency on the tradeoff between feeding and anti-predator behaviors. A second experiment examined temporal allocation of feeding across three light levels to determine if fish responded to risk differently in environments simulating dusk. Both experiments revealed significant effects of behavioral strategy on responses to temporal patterns of risk. English sole fully recovered feeding behaviors with increasing frequency of predator encounters and did not modify their risk response as light level decreased. Rock sole did not resume feeding behavior as risk frequency increased, however they relaxed anti-predator behavior under low light conditions. Halibut demonstrated intermediate responses, exhibiting limited recovery of feeding with increasing risk frequency, and they modified their risk response in a low light environment. These trends suggest that divergent behavioral strategies not only affect how organisms respond to risk in the short term but also impact how temporal variation in risk is incorporated into the behavioral decision-making process. Title: Divergent anti-predator strategies and risk allocation in juveniles of three North Pacific flatfishes Author: Boersma, Kate S. Frequent or lengthy predation risk can cause one of two modifications of prey feeding behavior: 1) postponement of feeding to less risky periods, or 2) resumption of feeding behavior despite persistent risk. North Pacific flatfishes exhibit both of these responses when confronted with temporal variation in risk, and this experimental series demonstrates that the particular response reflects species-specific behavioral strategies. Two laboratory experiments were conducted with juvenile English sole (Parophrys vetulus), northern rock sole (Lepidopsetta polyxystra), and Pacific halibut (Hippoglossus stenolepis), which inhabit the same nurseries in Alaska as juveniles but have been shown to exhibit different levels of risk aversion. One experiment explored the effects of variation in risk exposure frequency on the tradeoff between feeding and anti-predator behaviors. A second experiment examined temporal allocation of feeding across three light levels to determine if fish responded to risk differently in environments simulating dusk. Both experiments revealed significant effects of behavioral strategy on responses to temporal patterns of risk. English sole fully recovered feeding behaviors with increasing frequency of predator encounters and did not modify their risk response as light level decreased. Rock sole did not resume feeding behavior as risk frequency increased, however they relaxed anti-predator behavior under low light conditions. Halibut demonstrated intermediate responses, exhibiting limited recovery of feeding with increasing risk frequency, and they modified their risk response in a low light environment. These trends suggest that divergent behavioral strategies not only affect how organisms respond to risk in the short term but also impact how temporal variation in risk is incorporated into the behavioral decision-making process. Close

• 48. [Article] Fishing location choices in Oregon trawl fisheries : are fishermen risk-averse or risk-prone?

  Despite the fact that fishing is an inherently uncertain business, risk has rarely been formally recognized in fisheries science or management. Few fishery management plans include any form of risk assessment ...

  Citation × Citation Citation Abstract Copy Title: Fishing location choices in Oregon trawl fisheries : are fishermen risk-averse or risk-prone? Author: Trisak, Jiraporn Despite the fact that fishing is an inherently uncertain business, risk has rarely been formally recognized in fisheries science or management. Few fishery management plans include any form of risk assessment and those that do focus on minimizing risk caused by uncertainty associated with markets and environmental conditions. Fishermen's attitudes towards risk, whether they are risk-neutral, risk-averse, or risk-prone, have rarely been considered. Although fishermen's attitudes towards risk have been shown in theory to have an impact on fish populations, none of the previous investigations precisely identified whether fishermen are risk-neutral, risk-averse, or risk-prone. This research attempted to identify fishermen's attitudes towards risk from an analysis of their decisions about where to fish. The research applied risk-sensitive foraging theory to an analysis of data from the Oregon trawl fishery for 1991. The data were provided by the Oregon Department of Fisheries and Wildlife. One file contained tow-by-tow information for each fishing trip on landings by species, time spent fishing, type of gear, and fishing locations. A corresponding file contained trip-by-trip information on landings and price by species. The two data files were screened for inconsistencies and then classified into small homogeneous categories based on port, fishing gear, fishing area, and boat size. Various variance-discounting models were fitted to each category to determine fishermen's attitudes toward risk. The models describe the expected utility of fishing at a given distance from port as a linear function of the mean, variance, and third moment of the dollar value per hour of the retained catch. The unknown parameters were estimated from the data using logistic regression techniques. The results of the analysis indicated that in two of fifteen categories the fishermen were risk-averse, and in four categories they were risk-neutral. However, for the remaining nine categories the results were inconclusive and in some cases the fishermen's choice of fishing locations appeared illogical. Instead of preferring fishing grounds that generated higher profits, it appeared that fishermen actively avoided such grounds. The inconclusive and sometimes illogical results may have been due to inappropriate assumptions about the data and about the factors motivating fishermen's decisions. Additionally, there might have been some factors that could have affected the analysis which this research overlooked. For example, this research only accounted for monetary rewards, but fishermen may have preferences other than revenues and costs that influence their choice of fishing grounds. Title: Fishing location choices in Oregon trawl fisheries : are fishermen risk-averse or risk-prone? Author: Trisak, Jiraporn Despite the fact that fishing is an inherently uncertain business, risk has rarely been formally recognized in fisheries science or management. Few fishery management plans include any form of risk assessment and those that do focus on minimizing risk caused by uncertainty associated with markets and environmental conditions. Fishermen's attitudes towards risk, whether they are risk-neutral, risk-averse, or risk-prone, have rarely been considered. Although fishermen's attitudes towards risk have been shown in theory to have an impact on fish populations, none of the previous investigations precisely identified whether fishermen are risk-neutral, risk-averse, or risk-prone. This research attempted to identify fishermen's attitudes towards risk from an analysis of their decisions about where to fish. The research applied risk-sensitive foraging theory to an analysis of data from the Oregon trawl fishery for 1991. The data were provided by the Oregon Department of Fisheries and Wildlife. One file contained tow-by-tow information for each fishing trip on landings by species, time spent fishing, type of gear, and fishing locations. A corresponding file contained trip-by-trip information on landings and price by species. The two data files were screened for inconsistencies and then classified into small homogeneous categories based on port, fishing gear, fishing area, and boat size. Various variance-discounting models were fitted to each category to determine fishermen's attitudes toward risk. The models describe the expected utility of fishing at a given distance from port as a linear function of the mean, variance, and third moment of the dollar value per hour of the retained catch. The unknown parameters were estimated from the data using logistic regression techniques. The results of the analysis indicated that in two of fifteen categories the fishermen were risk-averse, and in four categories they were risk-neutral. However, for the remaining nine categories the results were inconclusive and in some cases the fishermen's choice of fishing locations appeared illogical. Instead of preferring fishing grounds that generated higher profits, it appeared that fishermen actively avoided such grounds. The inconclusive and sometimes illogical results may have been due to inappropriate assumptions about the data and about the factors motivating fishermen's decisions. Additionally, there might have been some factors that could have affected the analysis which this research overlooked. For example, this research only accounted for monetary rewards, but fishermen may have preferences other than revenues and costs that influence their choice of fishing grounds. Close

• 49. [Article] Characterizing perception of ecological risk

  35 pages

  Citation × Citation Citation Abstract Copy Title: Characterizing perception of ecological risk Author: McDaniels, Timothy, Axelrod, Lawrence J., Slovic, Paul Year: 2017, 1995 35 pages Title: Characterizing perception of ecological risk Author: McDaniels, Timothy, Axelrod, Lawrence J., Slovic, Paul Year: 2017, 1995 35 pages Close

• 50. [Article] Risk Assessment of the Mediterranean Seabass and Seabream industry in Greece: A Stochastic Simulation Approach Based on insurance Claims

  The Mediterranean finfish aquaculture is strongly represented from the successful industrial development of the mass production of the Mediterranean seabass (Dicentrarchus labrax) and seabream (Spaurus ...

  Citation × Citation Citation Abstract Copy Title: Risk Assessment of the Mediterranean Seabass and Seabream industry in Greece: A Stochastic Simulation Approach Based on insurance Claims Author: Tzovenis, Ioannis, Sorgeloos, Patrick, Viaene, Jacques, Theodorou, John A., Kotsonis, Antonios The Mediterranean finfish aquaculture is strongly represented from the successful industrial development of the mass production of the Mediterranean seabass (Dicentrarchus labrax) and seabream (Spaurus aurata), with Greece as the major producer country, contributing with approximately 57% of the global farmed production of both species. Despite the difficulty to obtain information from the private and public sector about the aquaculture insurance claims, the analysis of insurance data is necessary to develop a risk management strategy of the industry. The aim of the present work is to identify the major risks affecting the seabass/seabream aquaculture by examining qualitative and quantitative insurance claims from the early developmental stage (mid-80s) up to the maturation of the Greek sector (2000). A risk assessment based on scenario quantification and Monte Carlo Simulation with the ZHA WORKS 4.2 QUANT software is used to reveal percentile statistics of 1 Year/Worst out of x Years aggregate loss and thus to "harden" the basis for decision taking. The use of the past insurance experience provides forecasting trends for risk avoidance in the future and contributes to a strategy development for the sustainability of the sector. Title: Risk Assessment of the Mediterranean Seabass and Seabream industry in Greece: A Stochastic Simulation Approach Based on insurance Claims Author: Tzovenis, Ioannis, Sorgeloos, Patrick, Viaene, Jacques, Theodorou, John A., Kotsonis, Antonios The Mediterranean finfish aquaculture is strongly represented from the successful industrial development of the mass production of the Mediterranean seabass (Dicentrarchus labrax) and seabream (Spaurus aurata), with Greece as the major producer country, contributing with approximately 57% of the global farmed production of both species. Despite the difficulty to obtain information from the private and public sector about the aquaculture insurance claims, the analysis of insurance data is necessary to develop a risk management strategy of the industry. The aim of the present work is to identify the major risks affecting the seabass/seabream aquaculture by examining qualitative and quantitative insurance claims from the early developmental stage (mid-80s) up to the maturation of the Greek sector (2000). A risk assessment based on scenario quantification and Monte Carlo Simulation with the ZHA WORKS 4.2 QUANT software is used to reveal percentile statistics of 1 Year/Worst out of x Years aggregate loss and thus to "harden" the basis for decision taking. The use of the past insurance experience provides forecasting trends for risk avoidance in the future and contributes to a strategy development for the sustainability of the sector. Close