نتایج جستجو برای: marine reserve

تعداد نتایج: 123813  

2014
Vivitskaia J. Tulloch Hugh P. Possingham Stacy D. Jupiter Chris Roelfsema Ayesha I. Tulloch Carissa J. Klein

One of the most pervasive forms of uncertainty in data used to make conservation decisions is error associated with mapping of conservation features. Whilst conservation planners should consider uncertainty associated with ecological data to make informed decisions, mapping error is rarely, if ever, accommodated in the planning process. Here, we develop a spatial conservation prioritization app...

2005
R. Quentin Grafton

The paper analyses the economic payoffs from marine reserves using a stochastic optimal control model. The results show that even if the reserve and harvested populations face the same negative shocks, harvesting is optimal, the population is persistent and with no uncertainty over current stock size, a reserve can increase resource rents. Using actual fishery data we demonstrate that the payof...

Journal: :Mathematical biosciences 2012
Kunal Chakraborty T K Kar

The present paper describes a prey-predator type fishery model with prey dispersal in a two-patch environment, one of which is a free fishing zone and other is protected zone. The objective of the paper is to maximize the net economic revenue earn from the fishery through implementing the sustainable properties of the fishery to keep the ecological balance. Biological measures are introduced to...

2013
Jono R. Wilson Sarah R. Valencia Matthew C. Kay Hunter S. Lenihan

No-take marine reserves show great promise as conservation tools, yet the integration of reserves into assessment models for data-limited fisheries management is just emerging. We develop a framework for integrating marine reserves into two data-limited assessment models: spawning potential ratio (SPR) and yield per recruit (YPR). We use Monte Carlo simulation to test the applicability of the f...

Journal: :Management Science 2004
Geoffrey A. Meester Anuj Mehrotra Jerald S. Ault Edward K. Baker

R reports have raised serious concerns about the rapid declines of historically productive marine fishery resources and the degradation of essential fish habitats. This global crisis has spurred development of innovative management strategies to rebuild depleted fisheries and marine ecosystems. One highly touted strategy involves the design and creation of marine reserves (areas off limits to e...

2000
Marc Mangel

Marine reserves are increasingly proposed as a management tool. Models can play a valuable role in the evaluation of the possible benefits of reserves because they allow us to conduct many more investigations than could ever be done empirically. In this paper, I develop a model for a marine reserve for an open population subject to environmental uncertainty.

2012
Mark E. Bond Elizabeth A. Babcock Ellen K. Pikitch Debra L. Abercrombie Norlan F. Lamb Demian D. Chapman

Carcharhinid sharks can make up a large fraction of the top predators inhabiting tropical marine ecosystems and have declined in many regions due to intense fishing pressure. There is some support for the hypothesis that carcharhinid species that complete their life-cycle within coral reef ecosystems, hereafter referred to as "reef sharks", are more abundant inside no-take marine reserves due t...

Journal: :Current Biology 2010
Nigel Williams

Britain's new move makes a major concession to developing countries. " We are interested in trying to break the deadlock and find ways through some of the issues raised in Copenhagen, " Miliband said. " We do not want to let a technical argument about whether we have one treaty or two derail the process. We are determined to show flexibility as long as there is no undermining of environmental p...

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