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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] Fisheries in a Complex System

  An important subset of natural resource management addresses preserving and/or harvesting biological resources. Examples are policies that derive from the Endangered Species Act including habitat conservation ...

  Citation × Citation Citation Abstract Copy Title: Fisheries in a Complex System Author: Tschirhart, John, Finoff, David Year: 2001 An important subset of natural resource management addresses preserving and/or harvesting biological resources. Examples are policies that derive from the Endangered Species Act including habitat conservation plans, the U.S. Forest Service’s logging practices, and fishery management councils’ decisions regarding catches. To understand the effectiveness of management policies requires an understanding of the interactions between the natural world and the human economy, because economies and ecosystems are inextricably linked. Common economic variables such as incomes and prices affect and are affected by common ecosystem variables such as resiliency and species populations. In spite of the linkages between the two systems, models of economies and ecosystems usually disregard one another. Title: Fisheries in a Complex System Author: Tschirhart, John, Finoff, David Year: 2001 An important subset of natural resource management addresses preserving and/or harvesting biological resources. Examples are policies that derive from the Endangered Species Act including habitat conservation plans, the U.S. Forest Service’s logging practices, and fishery management councils’ decisions regarding catches. To understand the effectiveness of management policies requires an understanding of the interactions between the natural world and the human economy, because economies and ecosystems are inextricably linked. Common economic variables such as incomes and prices affect and are affected by common ecosystem variables such as resiliency and species populations. In spite of the linkages between the two systems, models of economies and ecosystems usually disregard one another. Close

• 3. [Article] Understanding Non-Compliance Behavior with U.S. Protected Species Regulations

  Abstract Only

  Citation × Citation Citation Abstract Copy Title: Understanding Non-Compliance Behavior with U.S. Protected Species Regulations Author: Das, Chhandita, Bisack, Kathryn Abstract Only Title: Understanding Non-Compliance Behavior with U.S. Protected Species Regulations Author: Das, Chhandita, Bisack, Kathryn Abstract Only Close

• 4. [Article] Exploration of United States Domestic Economic Impacts of the Cites Appendix I Listing for Bluefin Tuna

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Exploration of United States Domestic Economic Impacts of the Cites Appendix I Listing for Bluefin Tuna Author: Gentner, Brad Abstract only. Title: Exploration of United States Domestic Economic Impacts of the Cites Appendix I Listing for Bluefin Tuna Author: Gentner, Brad Abstract only. Close

• 5. [Article] An Application of Stated Preference Non-Market Valuation to Value Improvements to Threatened and Endangered Species

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: An Application of Stated Preference Non-Market Valuation to Value Improvements to Threatened and Endangered Species Author: Lew, Daniel, Wallmo, Kristy Abstract only. Title: An Application of Stated Preference Non-Market Valuation to Value Improvements to Threatened and Endangered Species Author: Lew, Daniel, Wallmo, Kristy Abstract only. Close

• 6. [Article] Alternative Ways of Managing Sea Resources: A Guideline for the Management of Endangered Stocks

  No poster available.

  Citation × Citation Citation Abstract Copy Title: Alternative Ways of Managing Sea Resources: A Guideline for the Management of Endangered Stocks Author: Crastes, Romain No poster available. Title: Alternative Ways of Managing Sea Resources: A Guideline for the Management of Endangered Stocks Author: Crastes, Romain No poster available. Close

• 7. [Article] Fisheries Policy Designs in Response to Climate Changes -- A Case Study of the Hawaii-based Longline Swordfish Fishery

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Fisheries Policy Designs in Response to Climate Changes -- A Case Study of the Hawaii-based Longline Swordfish Fishery Author: Pan, Minling, Li, Shichao Abstract only. Title: Fisheries Policy Designs in Response to Climate Changes -- A Case Study of the Hawaii-based Longline Swordfish Fishery Author: Pan, Minling, Li, Shichao Abstract only. Close

• 8. [Article] Optimal Management of Conflicting Species: Grey Seal (Halichoerus Grypus) and Baltic Salmon (Salmo Salar L.)

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Optimal Management of Conflicting Species: Grey Seal (Halichoerus Grypus) and Baltic Salmon (Salmo Salar L.) Author: Kulmala, Soile, Lindroos, Marko, Holma, Maija Abstract only. Title: Optimal Management of Conflicting Species: Grey Seal (Halichoerus Grypus) and Baltic Salmon (Salmo Salar L.) Author: Kulmala, Soile, Lindroos, Marko, Holma, Maija Abstract only. Close

• 9. [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

• 10. [Article] Marine Aquaculture in Indonesia: The present and future development

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Marine Aquaculture in Indonesia: The present and future development Author: Samson, Stepanus A., Watanabe, Seiichi, Setiarto, Agung, Mingkid, Winda Mercedes Research Paper Title: Marine Aquaculture in Indonesia: The present and future development Author: Samson, Stepanus A., Watanabe, Seiichi, Setiarto, Agung, Mingkid, Winda Mercedes Research Paper Close