| 来源类型 | Monograph (IIASA Interim Report) |
| 规范类型 | 报告 |
| Dynamics and management of stage-structured fish stocks. | |
| Meng X; Lundstroem NLP; Bodin M; Brannstrom Å | |
| 发表日期 | 2012 |
| 出版者 | IIASA, Laxenburg, Austria: IR-12-056 |
| 出版年 | 2012 |
| 语种 | 英语 |
| 摘要 | With increasing fishing pressures having brought several stocks to the brink of collapse, there is a need for developing efficient harvesting methods that account for factors beyond merely yield or profit. We consider the dynamics and management of a stage-structured fish stock. Our work is based on a consumer-resource model which De Roos et al. (2008) have derived as an approximation of a physiologically-structured counterpart. First, we rigorously prove the existence of steady states in both models, that the models share the same steady states, and that there exists at most one positive steady state. Furthermore, we carry out numerical investigations which suggest that a steady state is globally stable if it is locally stable Second, we consider multi-objective harvesting strategies which account for yield, profit, and the recovery potential of the fish stock. The recovery potential is a measure of how quickly a fish stock can recover from a major disturbance and serves as an indication of the extinction risk associated with a harvesting strategy. Our analysis reveals that a small reduction in yield or profit allows for a disproportional increase in recovery potential. We also show that there exists a harvesting strategy with yield close to the maximum sustainable yield (MSY) and profit close to that associated with the maximum economic yield (MEY). In offering a good compromise between MSY and MEY, we believe that this harvesting strategy is preferable in most instances. Third, we consider the impact of harvesting on population size structure and analytically determine the most and least harmful harvesting strategies. We conclude that the most harmful harvesting strategy consists of harvesting both adults and juveniles, while harvesting only adults is the least harmful strategy. Finally, we find that a high percentage of juvenile biomass indicates elevated extinction risk and might therefore serve as an early-warning signal of impending stock collapse. |
| 主题 | Evolution and Ecology (EEP) |
| URL | http://pure.iiasa.ac.at/id/eprint/10219/ |
| 来源智库 | International Institute for Applied Systems Analysis (Austria) |
| 资源类型 | 智库出版物 |
| 条目标识符 | http://119.78.100.153/handle/2XGU8XDN/125859 |
| 推荐引用方式 GB/T 7714 | Meng X,Lundstroem NLP,Bodin M,et al. Dynamics and management of stage-structured fish stocks.. 2012. |
| 条目包含的文件 | ||||||
| 文件名称/大小 | 资源类型 | 版本类型 | 开放类型 | 使用许可 | ||
| IR-12-056.pdf（2336KB） | 智库出版物 | 限制开放 | CC BY-NC-SA | 浏览 | ||
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