Dunn Daniel C, Maxwell Sara M, Boustany Andre M, Halpin Patrick N
Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC 27708;
Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529.
Proc Natl Acad Sci U S A. 2016 Jan 19;113(3):668-73. doi: 10.1073/pnas.1513626113. Epub 2016 Jan 4.
In response to the inherent dynamic nature of the oceans and continuing difficulty in managing ecosystem impacts of fisheries, interest in the concept of dynamic ocean management, or real-time management of ocean resources, has accelerated in the last several years. However, scientists have yet to quantitatively assess the efficiency of dynamic management over static management. Of particular interest is how scale influences effectiveness, both in terms of how it reflects underlying ecological processes and how this relates to potential efficiency gains. Here, we address the empirical evidence gap and further the ecological theory underpinning dynamic management. We illustrate, through the simulation of closures across a range of spatiotemporal scales, that dynamic ocean management can address previously intractable problems at scales associated with coactive and social patterns (e.g., competition, predation, niche partitioning, parasitism, and social aggregations). Furthermore, it can significantly improve the efficiency of management: as the resolution of the closures used increases (i.e., as the closures become more targeted), the percentage of target catch forgone or displaced decreases, the reduction ratio (bycatch/catch) increases, and the total time-area required to achieve the desired bycatch reduction decreases. In the scenario examined, coarser scale management measures (annual time-area closures and monthly full-fishery closures) would displace up to four to five times the target catch and require 100-200 times more square kilometer-days of closure than dynamic measures (grid-based closures and move-on rules). To achieve similar reductions in juvenile bycatch, the fishery would forgo or displace between USD 15-52 million in landings using a static approach over a dynamic management approach.
鉴于海洋固有的动态特性以及在管理渔业对生态系统影响方面持续存在的困难,在过去几年中,人们对动态海洋管理概念(即海洋资源的实时管理)的兴趣与日俱增。然而,科学家们尚未对动态管理相对于静态管理的效率进行定量评估。特别令人感兴趣的是,尺度如何影响有效性,这既体现在它如何反映潜在的生态过程,又体现在这与潜在的效率提升有何关联。在此,我们填补实证证据的空白,并进一步完善支撑动态管理的生态理论。我们通过模拟一系列时空尺度上的禁渔区,说明动态海洋管理能够解决与协同活动和社会模式(如竞争、捕食、生态位划分、寄生和社会聚集)相关尺度上以前难以解决的问题。此外,它能显著提高管理效率:随着所使用禁渔区分辨率的提高(即禁渔区变得更具针对性),放弃或转移的目标渔获量百分比降低,减少率(副渔获物/渔获量)增加,实现所需副渔获物减少量所需的总时间 - 面积减少。在所研究的情景中,较粗尺度的管理措施(年度时间 - 面积禁渔和月度全渔业禁渔)转移的目标渔获量将高达动态措施(基于网格的禁渔区和移动规则)的四到五倍,所需的禁渔区平方公里 - 天数比动态措施多100 - 200倍。为实现类似的幼鱼副渔获物减少量,采用静态方法的渔业在登陆量方面将比动态管理方法放弃或转移1500万至5200万美元。