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• 1. [Article] A Kalman Filter Approach to Estimating Marine Turtle Incidental Take Risk

  A principle U.S. fisheries management concern is ensuring compliance with Endangered Species Act requirements to limit incidental takes of listed species to levels which do not result in potential jeopardy ...

  Citation × Citation Citation Abstract Copy Title: A Kalman Filter Approach to Estimating Marine Turtle Incidental Take Risk Author: Stohs, Stephen, Kvamsdal, Sturla A principle U.S. fisheries management concern is ensuring compliance with Endangered Species Act requirements to limit incidental takes of listed species to levels which do not result in potential jeopardy to existing population stocks. Part of the risk assessment process involves an analysis of historic takes (bycatch) of ESA-listed species relative to fishing effort. Sample bycatch per unit of effort (BPUE) ratios are used to gauge the take risk to ESA-listed species posed by future fishing effort. The rare-event nature of protected species takes complicates the interpretation of sample BPUE ratios. For illustration, a total of 23 leatherback turtles were incidentally taken by fishermen in the California-Oregon drift gillnet fishery from the 1990 through 2006 fishing seasons in 7733 sets of fishing effort, with from 0 to 5 leatherback takes per season over the entire period. Should one conclude the incidental take risk was significantly higher during the season with 5 leatherback turtle takes than in seasons with 0 takes? To address this and related inference problems, we specify a state space model which describes the pattern of observed takes as a Poisson process conditional on the level of fishing effort. A time-varying Poisson rate parameter, expressed as BPUE, measures the time-varying level of take risk. A Kalman filter for Poisson processes is used to estimate the intertemporal variation in take risk from California-Oregon drift gillnet fishery observer data. A key question regards attributing the observed pattern of takes to randomness which drives fluctuations in observed takes versus intertemporal variation in the level of take risk. Title: A Kalman Filter Approach to Estimating Marine Turtle Incidental Take Risk Author: Stohs, Stephen, Kvamsdal, Sturla A principle U.S. fisheries management concern is ensuring compliance with Endangered Species Act requirements to limit incidental takes of listed species to levels which do not result in potential jeopardy to existing population stocks. Part of the risk assessment process involves an analysis of historic takes (bycatch) of ESA-listed species relative to fishing effort. Sample bycatch per unit of effort (BPUE) ratios are used to gauge the take risk to ESA-listed species posed by future fishing effort. The rare-event nature of protected species takes complicates the interpretation of sample BPUE ratios. For illustration, a total of 23 leatherback turtles were incidentally taken by fishermen in the California-Oregon drift gillnet fishery from the 1990 through 2006 fishing seasons in 7733 sets of fishing effort, with from 0 to 5 leatherback takes per season over the entire period. Should one conclude the incidental take risk was significantly higher during the season with 5 leatherback turtle takes than in seasons with 0 takes? To address this and related inference problems, we specify a state space model which describes the pattern of observed takes as a Poisson process conditional on the level of fishing effort. A time-varying Poisson rate parameter, expressed as BPUE, measures the time-varying level of take risk. A Kalman filter for Poisson processes is used to estimate the intertemporal variation in take risk from California-Oregon drift gillnet fishery observer data. A key question regards attributing the observed pattern of takes to randomness which drives fluctuations in observed takes versus intertemporal variation in the level of take risk. Close

• 2. [Article] Endangered, Threatened, and Protected Species: Challenges of Managing Living Marine Resources in an Internally Conflicted Regulatory Environment and the Opportunities They Present

  Natural resource management is a challenging undertaking in the best of circumstances. However, managing living marine resources is frequently confounded by the vast, alien, and oft-times hostile physical ...

  Citation × Citation Citation Abstract Copy Title: Endangered, Threatened, and Protected Species: Challenges of Managing Living Marine Resources in an Internally Conflicted Regulatory Environment and the Opportunities They Present Author: Queirolo, Lewis E. Year: 2001 Natural resource management is a challenging undertaking in the best of circumstances. However, managing living marine resources is frequently confounded by the vast, alien, and oft-times hostile physical environment within which the organisms reside. The subtleties and complexity of the marine life-web, which in important respects have come to include the traditional relationships, forged over millennia, of individual human populations, all contribute to the intricate biological, political, economic, and social undercurrents that define and drive the management decision-making process. The remarks and observations offered here pertain primarily to the U.S. Federal resource management process, as it bears on the exploitation and conservation of the fish, shellfish, mammals, birds, and other marine organisms of the U.S. Extended Economic Zone (EEZ). Prior to the establishment of the U.S. extended management zone, the principal role of the “Feds” in marine fisheries management was connected with bilateral and multilateral international agreements on “high-seas” access to (and conservation of) these open access or common-property resources. The predecessor agency of the National Marine Fisheries Service (NMFS), the Bureau of Commercial Fisheries, by-in-large, represented the U.S. “marine fisheries management” interests on the world’s oceans Title: Endangered, Threatened, and Protected Species: Challenges of Managing Living Marine Resources in an Internally Conflicted Regulatory Environment and the Opportunities They Present Author: Queirolo, Lewis E. Year: 2001 Natural resource management is a challenging undertaking in the best of circumstances. However, managing living marine resources is frequently confounded by the vast, alien, and oft-times hostile physical environment within which the organisms reside. The subtleties and complexity of the marine life-web, which in important respects have come to include the traditional relationships, forged over millennia, of individual human populations, all contribute to the intricate biological, political, economic, and social undercurrents that define and drive the management decision-making process. The remarks and observations offered here pertain primarily to the U.S. Federal resource management process, as it bears on the exploitation and conservation of the fish, shellfish, mammals, birds, and other marine organisms of the U.S. Extended Economic Zone (EEZ). Prior to the establishment of the U.S. extended management zone, the principal role of the “Feds” in marine fisheries management was connected with bilateral and multilateral international agreements on “high-seas” access to (and conservation of) these open access or common-property resources. The predecessor agency of the National Marine Fisheries Service (NMFS), the Bureau of Commercial Fisheries, by-in-large, represented the U.S. “marine fisheries management” interests on the world’s oceans Close

• 3. [Article] Sea Turtles of Bahia Magdalena, Baja California Sur, Mexico: Demand and Supply of an Endangered Species

  Sea turtles have historically been a primary resource for many of the coastal inhabitants of Bahia Magdalena, Baja California Sur, Mexico. Despite their endangered status and the implementation in 1990 ...

  Citation × Citation Citation Abstract Copy Title: Sea Turtles of Bahia Magdalena, Baja California Sur, Mexico: Demand and Supply of an Endangered Species Author: Garcia-Martinez, S., Nichols, W.J. Year: 2001 Sea turtles have historically been a primary resource for many of the coastal inhabitants of Bahia Magdalena, Baja California Sur, Mexico. Despite their endangered status and the implementation in 1990 of Mexican laws prohibiting the harvest of sea turtles, the demand for and the supply of these animals has persisted to some degree. To determine the current demand for sea turtles 122 surveys and 56 interviews were conducted (June 12th-30th, 1999) throughout the Bahia Magdalena region. Through a generalized least squares (GLS) analysis it was estimated that 35.7% of the variation in demand was explained by six independent variables. The GLS model shows that the family size, special occasions of consumption such as birthdays, and the decline in sea turtle populations positively affect the demand function. The person's occupation, monthly income, and the 1990 ban on sea turtle harvest negatively affect this demand. Ninety-four surveys and seventy interviews conducted in the region (July 24th-August 1st, 1999) were used to describe a supply function. The GLS estimation indicates that 27.8% of the variation in the supply of sea turtles in the bay is influenced by nine variables. Age, level of education, fishing practices, number of dependents, availability of sea turtles, and culture significantly affect the supply of sea turtles in the Bahia Magdalena region. Title: Sea Turtles of Bahia Magdalena, Baja California Sur, Mexico: Demand and Supply of an Endangered Species Author: Garcia-Martinez, S., Nichols, W.J. Year: 2001 Sea turtles have historically been a primary resource for many of the coastal inhabitants of Bahia Magdalena, Baja California Sur, Mexico. Despite their endangered status and the implementation in 1990 of Mexican laws prohibiting the harvest of sea turtles, the demand for and the supply of these animals has persisted to some degree. To determine the current demand for sea turtles 122 surveys and 56 interviews were conducted (June 12th-30th, 1999) throughout the Bahia Magdalena region. Through a generalized least squares (GLS) analysis it was estimated that 35.7% of the variation in demand was explained by six independent variables. The GLS model shows that the family size, special occasions of consumption such as birthdays, and the decline in sea turtle populations positively affect the demand function. The person's occupation, monthly income, and the 1990 ban on sea turtle harvest negatively affect this demand. Ninety-four surveys and seventy interviews conducted in the region (July 24th-August 1st, 1999) were used to describe a supply function. The GLS estimation indicates that 27.8% of the variation in the supply of sea turtles in the bay is influenced by nine variables. Age, level of education, fishing practices, number of dependents, availability of sea turtles, and culture significantly affect the supply of sea turtles in the Bahia Magdalena region. Close

• 4. [Article] Economic and Social Change in the Fishery

  A great deal is known about economic and social adjustments in modern societies, but the two are not well integrated in social science literature. The unique biological conditions in the fishery further ...

  Citation × Citation Citation Abstract Copy Title: Economic and Social Change in the Fishery Author: Castle, Emery N. Year: 2001 A great deal is known about economic and social adjustments in modern societies, but the two are not well integrated in social science literature. The unique biological conditions in the fishery further complicate decision making at both the micro and macro levels. An assessment is made of how well current private and public sector decision-making in the United States utilizes knowledge from the social and biological sciences in management of the Columbia River fishery. The interdisciplinary concept of social capital is used to integrate knowledge from fishery biology, resource economics, and systems science. Recommendations are made for reform of public sector management of the Columbia River Fishery. Title: Economic and Social Change in the Fishery Author: Castle, Emery N. Year: 2001 A great deal is known about economic and social adjustments in modern societies, but the two are not well integrated in social science literature. The unique biological conditions in the fishery further complicate decision making at both the micro and macro levels. An assessment is made of how well current private and public sector decision-making in the United States utilizes knowledge from the social and biological sciences in management of the Columbia River fishery. The interdisciplinary concept of social capital is used to integrate knowledge from fishery biology, resource economics, and systems science. Recommendations are made for reform of public sector management of the Columbia River Fishery. Close

• 5. [Article] Species Extinction and Cultural Arrogance: The Perils of Ignoring History

  For more than a century, politicians, newspaper editors, tate and federal fisheries managers, and their various constituencies with an interest in salmon have complained,lobbied and petitioned, sought ...

  Citation × Citation Citation Abstract Copy Title: Species Extinction and Cultural Arrogance: The Perils of Ignoring History Author: Robbins, William G. Year: 2001 For more than a century, politicians, newspaper editors, tate and federal fisheries managers, and their various constituencies with an interest in salmon have complained,lobbied and petitioned, sought legislative relief, and studied to near extinction the declining runs of the Pacific Northwest’s anadromous fish runs. All to no avail, of course. Management efforts have failed; the attempt to the establish reliable, predictive models has failed; massive federal expenditures to rescue crashing stocks have failed; and endeavors to achieve consensus about future policymaking have failed. And today one can add to the now familiar story of extinct and endangered salmon, similar tales about ocean groundfish, newly impoverished fishing communities, reductions in fleet size, and more federal bailouts. What is fascinating in the unveiling of this most recent story is the sense of history repeating itself as commercial fishers shift from one species to the next. Title: Species Extinction and Cultural Arrogance: The Perils of Ignoring History Author: Robbins, William G. Year: 2001 For more than a century, politicians, newspaper editors, tate and federal fisheries managers, and their various constituencies with an interest in salmon have complained,lobbied and petitioned, sought legislative relief, and studied to near extinction the declining runs of the Pacific Northwest’s anadromous fish runs. All to no avail, of course. Management efforts have failed; the attempt to the establish reliable, predictive models has failed; massive federal expenditures to rescue crashing stocks have failed; and endeavors to achieve consensus about future policymaking have failed. And today one can add to the now familiar story of extinct and endangered salmon, similar tales about ocean groundfish, newly impoverished fishing communities, reductions in fleet size, and more federal bailouts. What is fascinating in the unveiling of this most recent story is the sense of history repeating itself as commercial fishers shift from one species to the next. Close

• 6. [Article] Power, Fish, and the Greenhouse on the Columbia River

  The Columbia River in the Pacific Northwest region of the U.S. is home to the greatest hydroelectric system in the world. Its dams provide 75 percent of the power needs of nearly 10 million people. But ...

  Citation × Citation Citation Abstract Copy Title: Power, Fish, and the Greenhouse on the Columbia River Author: Buchanan, Shepard C. Year: 2001 The Columbia River in the Pacific Northwest region of the U.S. is home to the greatest hydroelectric system in the world. Its dams provide 75 percent of the power needs of nearly 10 million people. But the dams also create numerous obstacles to the survival of what was once the world’s greatest salmon fishery. The region spends over $500 million annually to try to restore the fishery and ensure its future survival. However, the changes in river operations implemented to meet fish needs make it much more difficult to meet other environmental goals, such as the development of renewable electric power resources. Renewable resources would help to alleviate the risks associated with global warming. This paper demonstrates an unfortunate irony: that the renewable resources advocated by environmental interests are incompatible with a hydro system that is operated for fish. Such resources could add billions of dollars to the costs of electric power, while providing minimal environmental benefits. Saving the fish and reducing greenhouse gases are two environmental goals that do not appear to be compatible. Title: Power, Fish, and the Greenhouse on the Columbia River Author: Buchanan, Shepard C. Year: 2001 The Columbia River in the Pacific Northwest region of the U.S. is home to the greatest hydroelectric system in the world. Its dams provide 75 percent of the power needs of nearly 10 million people. But the dams also create numerous obstacles to the survival of what was once the world’s greatest salmon fishery. The region spends over $500 million annually to try to restore the fishery and ensure its future survival. However, the changes in river operations implemented to meet fish needs make it much more difficult to meet other environmental goals, such as the development of renewable electric power resources. Renewable resources would help to alleviate the risks associated with global warming. This paper demonstrates an unfortunate irony: that the renewable resources advocated by environmental interests are incompatible with a hydro system that is operated for fish. Such resources could add billions of dollars to the costs of electric power, while providing minimal environmental benefits. Saving the fish and reducing greenhouse gases are two environmental goals that do not appear to be compatible. Close

• 7. [Article] Policy Conundrum: Restoring Wild Salmon to the Pacific Northwest

  Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, and socially divisive. Pa st restoration efforts have been largely unsuccessful. Society’s failure to ...

  Citation × Citation Citation Abstract Copy Title: Policy Conundrum: Restoring Wild Salmon to the Pacific Northwest Author: Lackey, Robert T. Year: 2001 Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, and socially divisive. Pa st restoration efforts have been largely unsuccessful. Society’s failure to reverse the continuing decline of wild salmon has the characteristics of a policy conundrum: nearly everyone supports, abstractly at least, restoring salmon runs; considerable public and private resources have been devoted to their restoration; but society collectively remains evidently unwilling to make the painful decisions clearly necessary to arrest their decline. The salmon policy conundrum is characterized by competing societal priorities being adjudicated in a political environment where few are willing to acknowledge publicly the future consequences of prior de facto policy choices. Decisions already made have greatly circumscribed the status of wild salmon in the Pacific Northwest through at least the next several decades. Barring a near wholesale reversal of many of society’s previous decisions (and apparent priorities), and allowing for considerable year-to-year and decade-to-decade variation in run size due in part to oscillations in climate and oceanic conditions, I conclude that through the twenty-first century, many, perhaps most, stocks of wild salmon in the Pacific Northwest likely will remain at their current low levels or continue to decline in spite of current protection and restoration efforts. Title: Policy Conundrum: Restoring Wild Salmon to the Pacific Northwest Author: Lackey, Robert T. Year: 2001 Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, and socially divisive. Pa st restoration efforts have been largely unsuccessful. Society’s failure to reverse the continuing decline of wild salmon has the characteristics of a policy conundrum: nearly everyone supports, abstractly at least, restoring salmon runs; considerable public and private resources have been devoted to their restoration; but society collectively remains evidently unwilling to make the painful decisions clearly necessary to arrest their decline. The salmon policy conundrum is characterized by competing societal priorities being adjudicated in a political environment where few are willing to acknowledge publicly the future consequences of prior de facto policy choices. Decisions already made have greatly circumscribed the status of wild salmon in the Pacific Northwest through at least the next several decades. Barring a near wholesale reversal of many of society’s previous decisions (and apparent priorities), and allowing for considerable year-to-year and decade-to-decade variation in run size due in part to oscillations in climate and oceanic conditions, I conclude that through the twenty-first century, many, perhaps most, stocks of wild salmon in the Pacific Northwest likely will remain at their current low levels or continue to decline in spite of current protection and restoration efforts. Close

• 8. [Article] Risk Analysis in Setting Allowable Harvests: Annual Catch Limits under the Magnuson Stevens Reauthorization Act

  Under the reauthorized Magnuson-Stevens Act (MSRA), US fisheries management councils must specify an annual catch limit (ACL) for each managed species and institute accountability measures (AMs) to ensure ...

  Citation × Citation Citation Abstract Copy Title: Risk Analysis in Setting Allowable Harvests: Annual Catch Limits under the Magnuson Stevens Reauthorization Act Author: Semmens, Kathryn Alese, Anderson, Lee G. Under the reauthorized Magnuson-Stevens Act (MSRA), US fisheries management councils must specify an annual catch limit (ACL) for each managed species and institute accountability measures (AMs) to ensure that actual harvest will not cause the stock to be overfished. While the details of implementation are still being developed, a set of Proposed Guidelines for performing ACL analysis has been developed. The purpose of this paper is to provide a preliminary assessment of these guidelines. The MSRA specifies two principles to be used as a framework for determining how Councils can comply with the ACL and AM measures. Both deal with uncertainty in the overall fisheries management process. The first is the separation between science and policy in setting the upper level on allowable harvests. The second is the requirement to take strong management actions to ensure that, given real world enforcement issues, the actual harvest in any year does not surpass the allowable harvest level. The procedure for applying the principles is quite complex and it goes beyond a strict interpretation of the written language in the law. However, it is consistent with current procedures and with commonly accepted principles in fisheries management policy. The Proposed Guidelines suggest that a distinction be made between scientific and implementation uncertainty. While the distinction may follow from the two principles, a preliminary look at the logical process of developing the required control rules for specifying Acceptable Biological Catch and Annual Catch Targets raises questions about the usefulness of this distinction in actual policy analysis. Title: Risk Analysis in Setting Allowable Harvests: Annual Catch Limits under the Magnuson Stevens Reauthorization Act Author: Semmens, Kathryn Alese, Anderson, Lee G. Under the reauthorized Magnuson-Stevens Act (MSRA), US fisheries management councils must specify an annual catch limit (ACL) for each managed species and institute accountability measures (AMs) to ensure that actual harvest will not cause the stock to be overfished. While the details of implementation are still being developed, a set of Proposed Guidelines for performing ACL analysis has been developed. The purpose of this paper is to provide a preliminary assessment of these guidelines. The MSRA specifies two principles to be used as a framework for determining how Councils can comply with the ACL and AM measures. Both deal with uncertainty in the overall fisheries management process. The first is the separation between science and policy in setting the upper level on allowable harvests. The second is the requirement to take strong management actions to ensure that, given real world enforcement issues, the actual harvest in any year does not surpass the allowable harvest level. The procedure for applying the principles is quite complex and it goes beyond a strict interpretation of the written language in the law. However, it is consistent with current procedures and with commonly accepted principles in fisheries management policy. The Proposed Guidelines suggest that a distinction be made between scientific and implementation uncertainty. While the distinction may follow from the two principles, a preliminary look at the logical process of developing the required control rules for specifying Acceptable Biological Catch and Annual Catch Targets raises questions about the usefulness of this distinction in actual policy analysis. Close

• 9. [Article] Fisheries Management Issues in Vietnam

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Fisheries Management Issues in Vietnam Author: Chu, Tien Vinh Abstract only. Title: Fisheries Management Issues in Vietnam Author: Chu, Tien Vinh Abstract only. Close