Optimal Fishing Policy for Species Replacement

物种更替的最佳捕捞政策

• 批准号: 10660174
• 负责人: MATSUDA Hiroyuki
• 金额: $ 2.11万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10660174/
• 关键词: stock fluctuation; risk assessment; strong year class; resource management; immature fish; Beyerton-Holt model; Beverton-Holt モデル; 繁殖価; 収穫価; 未定乗数法; マサバ; マイワシ; 異形配偶; 非協力ゲーム; 不確実性; 漁獲量変動; 順応管理; 最犬法; ベイズ法; 絶滅の恐れ; 持続可能な漁業; 生物多様性

Many fisheries have alternative target stocks and selectively exploit the one with the highest expected income. Although target switching is very common in practice, few attempts have thus far been made to study target switching. In this paper, we investigated the potential effects of target switching on the yield and sustainability of fish stocks. We simulated switching exploitation between two independent stocks, using a delay-difference model. Our study revealed that well-planned target switching increases yields and simultaneously decreases the risk of the stocks collapsing. Target switching decreases fishing pressure on the less abundant stock and helps the declined stock to recover. Therefore, the minimum stock level is increased by switching. As switching keeps both stocks at productive levels, the total yield is increased by switching. Target switching is effective, especially when the catchability increases with the depletion of a stock population. Target switching depends on the availability of information on stock abundance. Thus, we examined the vulnerability of switching to stock assessment errors. If the stock assessment is very uncertain, then little or no switching is recommended. Target switching can have substantial effects on fisheries. Therefore, we must investigate the mechanisms of switching and incorporate switching into management plans.

许多渔业具有替代目标股票，并有选择地利用预期收入最高的渔业。尽管目标切换在实践中非常普遍，但到目前为止，很少有尝试研究目标切换。在本文中，我们调查了目标转换对鱼类股票产量和可持续性的潜在影响。我们使用延迟差异模型模拟了两个独立股票之间的开关开发。我们的研究表明，计划完整的目标转换增加产量，同时降低了股票崩溃的风险。目标转换会降低较少库存的捕捞压力，并有助于股票恢复。因此，通过切换提高了最低库存水平。随着切换使这两种股票保持生产水平，通过切换增加了总收益率。目标切换是有效的，尤其是当可捕能力随着股票人群的耗竭而增加时。目标切换取决于有关库存丰度的信息的可用性。因此，我们检查了切换到库存评估错误的脆弱性。如果库存评估非常不确定，则很少或不建议进行切换。目标转换会对渔业产生重大影响。因此，我们必须研究切换的机制，并将切换纳入管理计划。

项目成果

松田裕之: "環境生態学序説"共立. 212 (2000)

松田博之：“环境生态学导论”Kyoritsu 212（2000）。

MATSUDA H & ABRAMS PA: "Why are equally-sized gametes so rare?"Evolutionary Ecology Research. 1. 769-784 (1999)

松田H

Matsuda H: "Compatibility between sustainable use・・・" Water Report. 97. 46-49 (1998)

Matsuda H：“可持续利用之间的兼容性……”水报告 97. 46-49 (1998)。

松田裕之: "生態系管理の逆理" 海洋. 30. 371-376 (1998)

Hiroyuki Matsuda：“生态系统管理的悖论”海洋。30。371-376（1998）

MATSUDA H, KAJI K, UNO H: "A Management Policy for sika deer based on sex"Researches Population Ecology. 41. 139-149 (1999)

MATSUDA H、KAJI K、UNO H：“基于性别的梅花鹿管理政策”研究种群生态学。