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• 1. [Article] Uses of ecosystem services provided by MPAs: how much do they impact the local economy?

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  Citation × Citation Citation Abstract Copy Title: Uses of ecosystem services provided by MPAs: how much do they impact the local economy? Author: Person, Jeremy, Le Direach, Laurence, Lavisse, Elodie, Roncin, Nicolas, Boncoeur, Jean, Crec'hiriou, Romain, Marcos Diego, Concepcion Abstract only. Title: Uses of ecosystem services provided by MPAs: how much do they impact the local economy? Author: Person, Jeremy, Le Direach, Laurence, Lavisse, Elodie, Roncin, Nicolas, Boncoeur, Jean, Crec'hiriou, Romain, Marcos Diego, Concepcion Abstract only. Close

• 2. [Article] Diversifying Artisanal Fishing Fleets in the Galapagos Marine Reserve

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  Citation × Citation Citation Abstract Copy Title: Diversifying Artisanal Fishing Fleets in the Galapagos Marine Reserve Author: Adams, Charles, Larkin, Sherry Abstract only. Title: Diversifying Artisanal Fishing Fleets in the Galapagos Marine Reserve Author: Adams, Charles, Larkin, Sherry Abstract only. Close

• 3. [Article] Persistence of Populations in Environments with an Interface

  We model a fish population in a spatial region comprising a marine protected area and a fishing ground separated by an interface. The model assumes conservation of biomass density and takes the form of ...

  Citation × Citation Citation Abstract Copy Title: Persistence of Populations in Environments with an Interface Author: Rekow, James A. We model a fish population in a spatial region comprising a marine protected area and a fishing ground separated by an interface. The model assumes conservation of biomass density and takes the form of a reaction diffusion equation with a logistic reaction term. At the interface, in addition to continuity of biomass density flux, two possible matching conditions are considered: continuity of population density and continuity of biomass density. Neumann conditions are imposed at the physical boundaries. The eigenvalues of the elliptic problem resulting from the linearization of the model are computed. Necessary and sufficient conditions for the largest eigenvalue to be positive are determined. We show that there exist positive eigenfunctions corresponding to this eigenvalue. If the largest eigenvalue is positive, the population persists, whereas if this eigenvalue is negative, the population goes extinct. A simple sufficient condition for persistence when biomass density is continuous is that the spatially averaged net growth rate is positive. Similarly, if the spatially averaged net body mass growth rate is positive, the population persists when population is continuous. A brief introduction is given on connections between parabolic partial differential equations and stochastic processes. Questions relating branching stochastic processes and properties of population models that incorporate interfaces are identified. Title: Persistence of Populations in Environments with an Interface Author: Rekow, James A. We model a fish population in a spatial region comprising a marine protected area and a fishing ground separated by an interface. The model assumes conservation of biomass density and takes the form of a reaction diffusion equation with a logistic reaction term. At the interface, in addition to continuity of biomass density flux, two possible matching conditions are considered: continuity of population density and continuity of biomass density. Neumann conditions are imposed at the physical boundaries. The eigenvalues of the elliptic problem resulting from the linearization of the model are computed. Necessary and sufficient conditions for the largest eigenvalue to be positive are determined. We show that there exist positive eigenfunctions corresponding to this eigenvalue. If the largest eigenvalue is positive, the population persists, whereas if this eigenvalue is negative, the population goes extinct. A simple sufficient condition for persistence when biomass density is continuous is that the spatially averaged net growth rate is positive. Similarly, if the spatially averaged net body mass growth rate is positive, the population persists when population is continuous. A brief introduction is given on connections between parabolic partial differential equations and stochastic processes. Questions relating branching stochastic processes and properties of population models that incorporate interfaces are identified. Close

• 4. [Article] Report and recommendations of salmon anchor habitat strategy work group

  The 2003 Oregon Legislature directed the Oregon Department of Forestry (ODF) to convene a citizen work group to review and evaluate the ODF Salmon Anchor Habitat Strategy for state forests in northwest ...

  Citation × Citation Citation Abstract Copy Title: Report and recommendations of salmon anchor habitat strategy work group Author: McCollister, Mark, Wilkeson, Ray, Hanneman, Paul, Westbrook, Helen, Moskowitz, Dave, Institute for Natural Resources, Griffith, John The 2003 Oregon Legislature directed the Oregon Department of Forestry (ODF) to convene a citizen work group to review and evaluate the ODF Salmon Anchor Habitat Strategy for state forests in northwest Oregon. In November, 2003 ODF contracted with the Institute for Natural Resources (INR) to support the SAH Work Group. INR designed and oversaw a process for the SAH Work Group that facilitated dialogue among interested parties, scientists, land management professionals, and policy makers. The goal was to illuminate the SAH policy, identify issues and develop recommendations while respecting the perspectives held by all parties. Title: Report and recommendations of salmon anchor habitat strategy work group Author: McCollister, Mark, Wilkeson, Ray, Hanneman, Paul, Westbrook, Helen, Moskowitz, Dave, Institute for Natural Resources, Griffith, John The 2003 Oregon Legislature directed the Oregon Department of Forestry (ODF) to convene a citizen work group to review and evaluate the ODF Salmon Anchor Habitat Strategy for state forests in northwest Oregon. In November, 2003 ODF contracted with the Institute for Natural Resources (INR) to support the SAH Work Group. INR designed and oversaw a process for the SAH Work Group that facilitated dialogue among interested parties, scientists, land management professionals, and policy makers. The goal was to illuminate the SAH policy, identify issues and develop recommendations while respecting the perspectives held by all parties. Close

• 5. [Article] Assessing the Impact of Mpas on Recreational Uses of A Marine Ecosystem: the Case of the Côte Bleue Marine Park (France)

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Assessing the Impact of Mpas on Recreational Uses of A Marine Ecosystem: the Case of the Côte Bleue Marine Park (France) Author: Charbonnel, Eric, Le Direach, Laurence, Lavisse, Elodie, Wilson, James, Alban, Frédérique, Roncin, Nicolas, Boncoeur, Jean Abstract only. Title: Assessing the Impact of Mpas on Recreational Uses of A Marine Ecosystem: the Case of the Côte Bleue Marine Park (France) Author: Charbonnel, Eric, Le Direach, Laurence, Lavisse, Elodie, Wilson, James, Alban, Frédérique, Roncin, Nicolas, Boncoeur, Jean Abstract only. Close

• 6. [Article] Predicting Resource Management Benefits By Simulating Angler Demand and Supply Responses

  The “product” travel cost model (PTC) improves supply and substitution specification in travel cost models (TCM), eliminating common biases in estimating welfare effects of qualitative changes at specific sites. ...

  Citation × Citation Citation Abstract Copy Title: Predicting Resource Management Benefits By Simulating Angler Demand and Supply Responses Author: Hanna, J. Edward, Koveshnikova, Tatiana, Talhelm, Daniel R., Victor, Peter The “product” travel cost model (PTC) improves supply and substitution specification in travel cost models (TCM), eliminating common biases in estimating welfare effects of qualitative changes at specific sites. Angling sites and participation are modeled as a system of product supplies and demands; changes in angling quality at specific sites are evaluated as changes in the supplies of relevant products. PTC assumes that each angler chooses from a selection of angling opportunities (i.e., products) based on access cost (i.e., travel cost) and the nature of each angling product. Key factors defining angling products (e.g., success rate, fish size) are derived from angler travel patterns: Anglers are assumed indifferent between sites providing identical angling products, so choose the lowest cost site. Therefore, the benefits of any management action not only differ from average welfare-change values, but are also site-specific. Changing angling attributes at a site changes its angling product: a unit of the existing product (potentially decreasing its supply) is lost while a unit of the newly created product is produced (potentially increasing its supply). Changes in supply at one site may alter angler participation patterns and the value of angling opportunities at the affected site plus at many other sites as well. Credit Valley Conservation contracted the application of the PTC examined here, namely angling in the Credit River watershed near Toronto, Canada. Average angler consumer surplus was estimated at $40 per angler day and varied according to angling product, location and season. Title: Predicting Resource Management Benefits By Simulating Angler Demand and Supply Responses Author: Hanna, J. Edward, Koveshnikova, Tatiana, Talhelm, Daniel R., Victor, Peter The “product” travel cost model (PTC) improves supply and substitution specification in travel cost models (TCM), eliminating common biases in estimating welfare effects of qualitative changes at specific sites. Angling sites and participation are modeled as a system of product supplies and demands; changes in angling quality at specific sites are evaluated as changes in the supplies of relevant products. PTC assumes that each angler chooses from a selection of angling opportunities (i.e., products) based on access cost (i.e., travel cost) and the nature of each angling product. Key factors defining angling products (e.g., success rate, fish size) are derived from angler travel patterns: Anglers are assumed indifferent between sites providing identical angling products, so choose the lowest cost site. Therefore, the benefits of any management action not only differ from average welfare-change values, but are also site-specific. Changing angling attributes at a site changes its angling product: a unit of the existing product (potentially decreasing its supply) is lost while a unit of the newly created product is produced (potentially increasing its supply). Changes in supply at one site may alter angler participation patterns and the value of angling opportunities at the affected site plus at many other sites as well. Credit Valley Conservation contracted the application of the PTC examined here, namely angling in the Credit River watershed near Toronto, Canada. Average angler consumer surplus was estimated at $40 per angler day and varied according to angling product, location and season. Close