125 research outputs found
The Silver Anniversary of the United Statesâ Exclusive Economic Zone: Twenty-Five Years of Ocean Use and Abuse, and the Possibility of a Blue Water Public Trust Doctrine
Sustainably managing marine ecosystems has proved nearly impossible, with few success stories. Ecosystem management failures largely stem from the traditional sector-by-sector, issue-by-issue approach to managing ocean-borne activitiesâan approach that is fundamentally unable to keep pace with the dynamics of coupled human, ecologi cal and oceanographic systems. In the United States today there are over twenty federal agencies and thirty-five coastal states and territories operating under dozens of statutory authorities shaping coastal and ocean policy. Among marine ecologists and policy experts there is an emerging consensus that a major overhaul in U.S. ocean governance is necessary. This Article suggests that the public trust doctrineâan ancient legal concept that is already incorporated in U.S. state coastal lawsâcan uniquely provide a unifying concept for U.S. federal ocean governance. Though the public trust concept can be located in the legal systems of many countries, it robustly manifests in the United States, where it has historically protected the publicâs rights to fishing, navigation, and commerce in and over navigable waterways and tidal waters. In its most basic form, the doctrine obliges governments to manage common natural resources, the body of the trust, in the best interest of their citizens, the beneficiaries of the trust. Today the public trust doctrin e is integral to the protection of coastal ecosystems and beach access in many states and has even made its way into state constitutions. It would be simple, and seemingly logical, to assume that the same fiduciary responsibility of states to protect public trust uses of their waters extends to all marine resources within the United Statesâ 200-mile Exclusive Economic Zone (EEZ). However an artificial line has been drawn around state waters, and the legal authority and responsibility of the U.S. government to protect public trust resources in the vast space of its EEZ (the largest of any country on earth) have never been fully and expressly established. Securing the place of the public trust doctrine in U.S. federal oceans management would be valuable, given the immense pressure to exploit EEZ resources, the failure of the current regulatory approach, improved scientific understanding of the interconnected nature of ocean ecosystems, and the growing demand for sustainable management of ocean resources. This Article will outline the development of statesâ public trust doctrines; discuss the expansion of U.S. sovereignty over its neighboring ocean waters during the twentieth century; analyze possible avenues for expanding the doctrine to federal waters; and consider how a federal public trust doctrine could clarify some specific emerging issues in U.S. oceans management. At the heart of our analysis lie three questions: (1) does a federal public trust doctrine exist; (2) if so, can we rightfully extend it to include the entirety of the U.S. ocean waters; and (3) could the doctrine provide the missing catalyst for federal agencies to manage the use of U.S. ocean resources in a coordinated, sustainable fashion
Assessing Population Responses to Multiple Anthropogenic Effects: A Case Study with Brook Trout
Population declines are often caused by multiple factors, including anthropogenic
ones that can be mitigated or reversed to enhance population recovery. We used
a size-classified matrix population model to examine multiple anthropogenic effects on a
population and determine which factors are most (or least) important to population dynamics.
We modeled brook trout (Salvelinus fontinalis) in southern Appalachian mountain
streams responding to multiple anthropogenic effects including the introduction of an exotic
salmonid species (rainbow trout, Oncorhynchus mykiss), a decrease in pH (through acidic
deposition), an increase in siltation (from roadbuilding and logging), and an increase in
fishing pressure.
Potential brook trout responses to rainbow trout include a decrease in survival rate of
small fish, a change in density dependence in survival of small fish, and a decrease in growth
rates of all sizes. When we included these responses in the population model, we found that
population size tended to decrease with an increase in small-fish growth rate (producing a
population with fewer, but larger, fish). In addition, changes in patterns of density-dependent
survival also had a strong impact on both population size and size structure. Brook trout
respond to decreases in pH with decreased growth rate in all size classes, decreased survival
rates of small fish, and decreased egg-to-larva survival rates. This combination of effects, at
magnitudes documented in laboratory experiments, had severe negative impacts on the modeled
population. If siltation effects were severe, the extreme increase in egg-to-larva mortality
could have strong negative effects on the population. However, even very strong increases
in large fish mortality associated with sport harvesting were not likely to cause a local
extinction. In all of these cases, the interaction of drastic changes in population size structure
with randomly occurring floods or droughts may lead to even stronger negative impacts than
those predicted from the deterministic model.
Because these fish can reproduce at a small size, negative impacts on survival of the
largest fish were not detrimental to the persistence of the population. Because survival of
small juveniles is density dependent, even moderate decreases in survival in this stage had
little effect on the ultimate population size. In general, a brook trout population will respond
most negatively to factors that decrease survival of large juveniles and small adults, and
growth rates of small juveniles.This work was supported by the Lucas Fellowship in Biomathematics at North Carolina State University (to E. A.
Marschall), the J. F. Allen Award from the American Fisheries Society (to E. A. Marschall), an Electric Power Research
Institute Fellowship in Population Dynamics (to E. A. Marschall), a U.S. Forest Service Cost-Share Agreement (to L.B. Crowder and E. A. Marschall), the Department of Zoology
at North Carolina State University (to L. B. Crowder), and the Department of Zoology at The Ohio State University (to E. A. Marschall)
Mitigating By-Catch of Diamondback Terrapins in Crab Pots
ABSTRACT Chronic by-catch of diamondback terrapins (Malaclemys terrapin) in blue crab (Callinectes sapidus) pots is a concern for terrapin conservation along the United States Atlantic and Gulf of Mexico coasts. Despite the availability of by-catch reduction devices (BRDs) for crab pots, adoption of BRDs has not been mandated and by-catch of terrapins continues. We conducted experimental fishing studies in North Carolina's year-round blue crab fishery from 2000 to 2004 to evaluate the ability of various BRDs to reduce terrapin by-catch without a concomitant reduction in the catch of blue crabs. In 4,822 crab pot days fished, we recorded only 21 terrapin captures. Estimated capture rates were 0.003 terrapins/pot per day in hard crab experimental fishing and 0.008 terrapins/pot per day in peeler experimental fishing. All terrapin captures occurred from April to mid-May within 321.4 m of the shoreline. Longer soak times produced more dead terrapins, with 4 live and 4 dead during hard crab experimental fishing and 11 live and 2 dead during peeler experimental fishing. The 4.0-cm BRDs in fall and 4.5-cm and 5.0-cm BRDs in spring reduced the catch of legal-sized male hard crabs by 26.6%, 21.2%, and 5.7%, respectively. Only the 5.0-cm BRDs did not significantly affect the catch of legal-sized hard male crabs. However, BRDs had no measurable effect on catch of target crabs in the peeler crab fishery. Our results identify 3 complementary and economically feasible tools for blue crab fishery managers to exclude terrapins from commercially fished crab pots in North Carolina: 1) gear modifications (e.g., BRDs); 2) distance-to-shore restrictions; and 3) time-of-year regulations. These measures combined could provide a reduction in terrapin by-catch of up to 95% without a significant reduction in target crab catch. Ă 2011 The Wildlife Society
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Organizational perspectives on sustainable ocean governance: A multi-stakeholder, meta-organization model of collective action
Although scholars have thoroughly explored theories and practices of formal and informal governance for oceans, most of the research has concentrated on interactions among individuals, or organizations within a sector. The emerging literature from management science argues that meta-organizations, organizations which members are themselves organizations, and especially cross-sectoral meta-organizations, may be a critical concept for scientists, public decision makers, managers, local communities and other actors in ocean governance. A meta-organization’s main attributes (i.e., bringing together different formal organizations, consensus-based decision making process, little to no hierarchy, diversity of membership, information-production and collective capacity building and self-regulation mechanisms) can foster critically necessary collaborative behaviors among competitors and across sectors. Here we review key concepts regarding meta-organizations, study six examples of meta-organizations in marine systems, and outline how these advances in management and policy could foster cooperation rather than competition within and among sectors in ocean governance. Meta-organization thinking therefore can help us understand, but also frame and encourage, cross-sectoral collective actions that are solutions-oriented.</p
Fish Cohort Dynamics: Application of Complementary Modeling Approaches
The recruitment to the adult stock of a fish population is a function of both environmental conditions and the dynamics of juvenile fish cohorts. These dynamics can be quite complicated and involve the size structure of the cohort. Two types of models, i-state distribution models (e.g., partial differential equations) and i-state configuration models (computer simulation models following many individuals simultaneously), have been developed to study this type of question. However, these two model types have not to our knowledge previously been compared in detail. Analytical solutions are obtained for three partial differential equation models of early life-history fish cohorts. Equivalent individual-by-individual computer simulation models are also used. These two approaches can produce similar results, which suggests that one may be able to use the approaches interchangeably under many circumstances. Simple uncorrected stochasticity in daily growth is added to the individual-by-individual models, and it is shown that this produces no significant difference from purely deterministic situations. However, when the stochasticity was temporally correlated such that a fish growing faster than the mean 1 d has a tendency to grow faster than the mean the next day, there can be great differences in the outcomes of the simulations.This research was sponsored in part by the Electric Power Research Institute under contract no. RP2932-2 (DOE no. ERD-87-672) with the U.S. Department of Energy under
contract no. DE-AC05-84OR21400 with Martin Marietta Energy Systems, and in part by grant no. NAI6RG0492-01 from the Coastal Ocean Program of the National Oceanic and Atmospheric Administration (NOAA) to the University of North Carolina Sea Grant College Program
Social drivers forewarn of marine regime shifts
Some ecosystems can undergo regime shifts to alternative compositions of species. Although ecological indicators can identify approaching regime shifts, we propose that rapid changes in the social drivers underlying ecosystem change may provide additional and potentially earlier indicators of impending shifts. We demonstrate this by reconstructing the underlying social drivers of four iconic marine regime shifts: Pacific kelp forests, Northwest Atlantic continental shelf, Jamaican coral reefs, and the Chesapeake Bay estuary. In all cases, a range of social drivers â including opening of lucrative markets, technological innovations, and policies that enhanced the driver â ultimately prompted these ecosystem shifts. Drawing on examples emerging from environmental management practice, we present three practical recommendations for using social drivers as early indicators: monitor social change, determine social trigger points, and identify policy responses. We argue that accounting for the underlying social drivers of ecosystem change could improve decision making
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Reaching consensus for conserving the global commons: The case of the Ross Sea, Antarctica
In October 2016, the international community made history by adopting the world's largest marine protected area in the Ross Sea, Antarctica—by consensus. Achieving this feat required tradeâoffs and compromise among the 24âMember States (plus the European Union) comprising the Commission for the Conservation of Antarctic Marine Living Resources. The process took 5 years of intense international negotiations and more than 10 years of scientific planning. Based on interviews with national delegations and other stakeholders, 5 years of participatory observation of Commission meetings (2012–2016), and analysis of hundreds of documents, we present unique insights that explain the conditions that stalled or facilitated the adoption of the Ross Sea MPA. These included economic interests, geopolitics, an erosion of trust, highâlevel diplomacy, and the compromises that were ultimately necessary. We reflect on lessons learned as the world considers how to achieve future largeâscale conservation successes in the global commons.</p
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