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| Beckensteiner, Jennifer; Kaplan, David; Scheld, Andrew M.. |
| The eastern oyster once provided major societal and ecosystem benefits, but these benefits have been threatened in recent decades by large declines in oyster harvests. In many areas, recovery of oyster aquaculture faces significant societal opposition and spatial constraints limiting its ability to meet expectations regarding future food needs and provision of ecosystem services. In Virginia, oyster aquaculture has begun to expand, concurrent with an increase in subaqueous leased areas (over 130,000 acres of grounds are currently leased). Though private leases must in theory be used for oyster production, in practice, they can be held for other reasons, such as speculation or intentional exclusion of others. These factors have led to large variation over... |
| Tipo: Text |
Palavras-chave: Crassostrea virginica; Oyster aquaculture; Chesapeake Bay; Spatial management; User conflicts. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00611/72337/71162.pdf |
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| Stephenson, Fabrice; Goetz, Kimberly; Sharp, Ben R.; Mouton, Theophile; Beets, Fenna L.; Roberts, Jim; Macdiarmid, Alison B.; Constantine, Rochelle; Lundquist, Carolyn J.; Sarmento Cabral, Juliano. |
| Aim Cetaceans are inherently difficult to study due to their elusive, pelagic and often highly migratory nature. New Zealand waters are home to 50% of the world's cetacean species, but their spatial distributions are poorly known. Here, we model distributions of 30 cetacean taxa using an extensive at‐sea sightings dataset (n > 14,000) and high‐resolution (1 km2) environmental data layers. Location New Zealand's Exclusive Economic Zone (EEZ). Methods Two models were used to predict probability of species occurrence based on available sightings records. For taxa with <50 sightings (n = 15), Relative Environmental Suitability (RES), and for taxa with ≥50 sightings (n = 15), Boosted Regression Tree (BRT) models were used. Independently collected... |
| Tipo: Text |
Palavras-chave: Boosted regression tree models; Cetacean distribution; New Zealand; Relative environmental suitability models; Spatial management; Species distribution models. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00606/71827/70345.pdf |
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| Sanchirico, James N.. |
| Marine reserves are gaining attention around the world as a tool to both conserve ocean resources and improve the productivity of fisheries. Using simulation analysis, we investigate in a limited-entry fishery comprising nine subpopulations the inherent bioeconomic trade-offs associated with cost-effective designs of marine reserve networks' that is, the trade-offs between the degree of connectedness of a site and the biological and economic heterogeneity. We find in many cases that closing two low-value patches can result in larger biological gains and lower costs than closing one high-value patch. We also simulate biological productivity effects after creation of a reserve and find that under special conditions, aggregate sustainable rents are maximized... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Limited-entry; Marine reserve networks; Spatial management; Resource /Energy Economics and Policy; Q22. |
| Ano: 2003 |
URL: http://purl.umn.edu/10624 |
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