Two species of intertidal fucoid algae, Pelvetia compressa and Hesperophycus californicus, are co... more Two species of intertidal fucoid algae, Pelvetia compressa and Hesperophycus californicus, are commonly found along moderately wave exposed rocky intertidal regions along the California coast. Both species decrease in size and abundance going from wave-protected to waveexposed intertidal areas. On the west end of Santa Cruz Island there is a noticeable gradient in wave exposure from Forney Cove to Frasier Point. In order to evaluate the effects of both wave exposure and tidal height on size and survival of these two species, we transplanted 20 adults and juveniles of both species from a wave-protected site (Forney) to an adjacent wave-exposed site (Frasier) at both high and low tidal heights, as well as 20 individuals of each species and age from Forney to Forney to control for transplant effects. Survival of adult Pelvetia was highest in the low zone at Frasier and low at both Forney and Frasier high. Survival of Pelvetia juveniles was extremely low at both tidal heights at Frasier...
Established in September 2018, the High Level Panel for a Sustainable Ocean Economy (HLP) is a un... more Established in September 2018, the High Level Panel for a Sustainable Ocean Economy (HLP) is a uniqueinitiative of 14 serving heads of government committed to catalysing bold, pragmatic solutions for oceanhealth and wealth that support the Sustainable Development Goals (SDGs) and build a better future for peopleand the planet. By working with governments, experts and stakeholders from around the world, the High LevelPanel aims to develop a roadmap for rapidly transitioning to a sustainable ocean economy, and to trigger,amplify and accelerate responsive action worldwide.
Future effects of climate change on ocean fisheries could be more than offset by management refor... more Future effects of climate change on ocean fisheries could be more than offset by management reforms for current fisheries.
The December 2003/January 2004 issue of MPA News offered two essays by scientists on marine reser... more The December 2003/January 2004 issue of MPA News offered two essays by scientists on marine reserve research. One questioned the rigor with which reserve research has been conducted, while the other explained difficulties involved in studying reserves, including finding adequate control sites. The essays presented a dilemma: we all want the best science on reserves, but to get it will require significantly more time and money — resources that are already scarce for managers. Readers responded to the essays with a range of views, from arguing that the state of reserve science is stronger than was depicted, to suggesting that scientists should focus more attention on other issues, like socioeconomic factors in reserve success or the effects of pollution on MPAs. Because of the amount of feedback, we have devoted a larger-than-usual portion of this month’s issue to letters. Here, MPA News highlights four of the responses received.
Canadian Journal of Fisheries and Aquatic Sciences
Managing natural resources under large-scale environmental fluctuations like the El Niño Southern... more Managing natural resources under large-scale environmental fluctuations like the El Niño Southern Oscillation (ENSO) is likely to become increasingly important under climate change. Forecasts of environmental conditions are improving, but the best response to an unfavorable forecast remains unclear; many practitioners advocate reducing harvest as a more precautionary approach, while prior economic theory favors increasing harvest. Using logistic and age-structured fisheries models, we show that informational constraints — uncertain stock estimates and restrictions on harvest policies — play a central role in choosing how to respond to a forecasted shock. With perfect knowledge and no policy constraints, risk-neutral managers should increase harvest when a negative shock is forecast. However, informational constraints may drive the optimal response to a forecast of a negative shock toward or away from precaution. Precautionary forecast responses arise when informational constraints m...
Understanding spatio-temporal variability in the demography of harvested species is essential to ... more Understanding spatio-temporal variability in the demography of harvested species is essential to improve sustainability, especially if there is large geographic variation in demography. Reproductive patterns commonly vary spatially, which is particularly important for management of "roe"-based fisheries, since profits depend on both the number and reproductive condition of individuals. The red sea urchin, Mesocentrotus franciscanus, is harvested in California for its roe (gonad), which is sold to domestic and international sushi markets. The primary driver of price within this multi-million-dollar industry is gonad quality. A relatively simple measure of the fraction of the body mass that is gonad, the gonadosomatic index (GSI), provides important insight into the ecological and environmental factors associated with variability in reproductive quality, and hence value within the industry. We identified the seasonality of the reproductive cycle and determined whether it var...
Marine Protected Areas (MPA) are important management tools shown to protect marine organisms, re... more Marine Protected Areas (MPA) are important management tools shown to protect marine organisms, restore biomass, and increase fisheries yields. While MPAs have been successful in meeting these goals for many relatively sedentary species, highly mobile organisms may get few benefits from this type of spatial protection due to their frequent movement outside the protected area. The use of a large MPA can compensate for extensive movement, but testing this empirically is challenging, as it requires both large areas and sufficient time series to draw conclusions. To overcome this limitation, MPA models have been used to identify designs and predict potential outcomes, but these simulations are highly sensitive to the assumptions describing the organism's movements. Due to recent improvements in computational simulations, it is now possible to include very complex movement assumptions in MPA models (e.g. Individual Based Model). These have renewed interest in MPA simulations, which im...
Two species of intertidal fucoid algae, Pelvetia compressa and Hesperophycus californicus, are co... more Two species of intertidal fucoid algae, Pelvetia compressa and Hesperophycus californicus, are commonly found along moderately wave exposed rocky intertidal regions along the California coast. Both species decrease in size and abundance going from wave-protected to waveexposed intertidal areas. On the west end of Santa Cruz Island there is a noticeable gradient in wave exposure from Forney Cove to Frasier Point. In order to evaluate the effects of both wave exposure and tidal height on size and survival of these two species, we transplanted 20 adults and juveniles of both species from a wave-protected site (Forney) to an adjacent wave-exposed site (Frasier) at both high and low tidal heights, as well as 20 individuals of each species and age from Forney to Forney to control for transplant effects. Survival of adult Pelvetia was highest in the low zone at Frasier and low at both Forney and Frasier high. Survival of Pelvetia juveniles was extremely low at both tidal heights at Frasier...
Established in September 2018, the High Level Panel for a Sustainable Ocean Economy (HLP) is a un... more Established in September 2018, the High Level Panel for a Sustainable Ocean Economy (HLP) is a uniqueinitiative of 14 serving heads of government committed to catalysing bold, pragmatic solutions for oceanhealth and wealth that support the Sustainable Development Goals (SDGs) and build a better future for peopleand the planet. By working with governments, experts and stakeholders from around the world, the High LevelPanel aims to develop a roadmap for rapidly transitioning to a sustainable ocean economy, and to trigger,amplify and accelerate responsive action worldwide.
Future effects of climate change on ocean fisheries could be more than offset by management refor... more Future effects of climate change on ocean fisheries could be more than offset by management reforms for current fisheries.
The December 2003/January 2004 issue of MPA News offered two essays by scientists on marine reser... more The December 2003/January 2004 issue of MPA News offered two essays by scientists on marine reserve research. One questioned the rigor with which reserve research has been conducted, while the other explained difficulties involved in studying reserves, including finding adequate control sites. The essays presented a dilemma: we all want the best science on reserves, but to get it will require significantly more time and money — resources that are already scarce for managers. Readers responded to the essays with a range of views, from arguing that the state of reserve science is stronger than was depicted, to suggesting that scientists should focus more attention on other issues, like socioeconomic factors in reserve success or the effects of pollution on MPAs. Because of the amount of feedback, we have devoted a larger-than-usual portion of this month’s issue to letters. Here, MPA News highlights four of the responses received.
Canadian Journal of Fisheries and Aquatic Sciences
Managing natural resources under large-scale environmental fluctuations like the El Niño Southern... more Managing natural resources under large-scale environmental fluctuations like the El Niño Southern Oscillation (ENSO) is likely to become increasingly important under climate change. Forecasts of environmental conditions are improving, but the best response to an unfavorable forecast remains unclear; many practitioners advocate reducing harvest as a more precautionary approach, while prior economic theory favors increasing harvest. Using logistic and age-structured fisheries models, we show that informational constraints — uncertain stock estimates and restrictions on harvest policies — play a central role in choosing how to respond to a forecasted shock. With perfect knowledge and no policy constraints, risk-neutral managers should increase harvest when a negative shock is forecast. However, informational constraints may drive the optimal response to a forecast of a negative shock toward or away from precaution. Precautionary forecast responses arise when informational constraints m...
Understanding spatio-temporal variability in the demography of harvested species is essential to ... more Understanding spatio-temporal variability in the demography of harvested species is essential to improve sustainability, especially if there is large geographic variation in demography. Reproductive patterns commonly vary spatially, which is particularly important for management of "roe"-based fisheries, since profits depend on both the number and reproductive condition of individuals. The red sea urchin, Mesocentrotus franciscanus, is harvested in California for its roe (gonad), which is sold to domestic and international sushi markets. The primary driver of price within this multi-million-dollar industry is gonad quality. A relatively simple measure of the fraction of the body mass that is gonad, the gonadosomatic index (GSI), provides important insight into the ecological and environmental factors associated with variability in reproductive quality, and hence value within the industry. We identified the seasonality of the reproductive cycle and determined whether it var...
Marine Protected Areas (MPA) are important management tools shown to protect marine organisms, re... more Marine Protected Areas (MPA) are important management tools shown to protect marine organisms, restore biomass, and increase fisheries yields. While MPAs have been successful in meeting these goals for many relatively sedentary species, highly mobile organisms may get few benefits from this type of spatial protection due to their frequent movement outside the protected area. The use of a large MPA can compensate for extensive movement, but testing this empirically is challenging, as it requires both large areas and sufficient time series to draw conclusions. To overcome this limitation, MPA models have been used to identify designs and predict potential outcomes, but these simulations are highly sensitive to the assumptions describing the organism's movements. Due to recent improvements in computational simulations, it is now possible to include very complex movement assumptions in MPA models (e.g. Individual Based Model). These have renewed interest in MPA simulations, which im...
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