Johnson Andrew Frederick, Moreno-Báez Marcia, Giron-Nava Alfredo, Corominas Julia, Erisman Brad, Ezcurra Exequiel, Aburto-Oropeza Octavio
Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA, United States of America.
Centro para la Biodiversidad Marina y la Conservación, La Paz, Mexico.
PLoS One. 2017 Apr 13;12(4):e0174064. doi: 10.1371/journal.pone.0174064. eCollection 2017.
To gauge the collateral impacts of fishing we must know where fishing boats operate and how much they fish. Although small-scale fisheries land approximately the same amount of fish for human consumption as industrial fleets globally, methods of estimating their fishing effort are comparatively poor. We present an accessible, spatial method of calculating the effort of small-scale fisheries based on two simple measures that are available, or at least easily estimated, in even the most data-poor fisheries: the number of boats and the local coastal human population. We illustrate the method using a small-scale fisheries case study from the Gulf of California, Mexico, and show that our measure of Predicted Fishing Effort (PFE), measured as the number of boats operating in a given area per day adjusted by the number of people in local coastal populations, can accurately predict fisheries landings in the Gulf. Comparing our values of PFE to commercial fishery landings throughout the Gulf also indicates that the current number of small-scale fishing boats in the Gulf is approximately double what is required to land theoretical maximum fish biomass. Our method is fishery-type independent and can be used to quantitatively evaluate the efficacy of growth in small-scale fisheries. This new method provides an important first step towards estimating the fishing effort of small-scale fleets globally.
为了评估捕鱼的附带影响，我们必须了解渔船的作业地点以及捕鱼量。尽管小规模渔业捕捞上岸供人类消费的鱼类数量与全球工业船队大致相同，但估算其捕捞努力量的方法相对较差。我们提出了一种易于理解的空间方法，用于计算小规模渔业的捕捞努力量，该方法基于两个简单的指标，即使在数据最为匮乏的渔业中也可获取，或至少易于估算：船只数量和当地沿海人口数量。我们以墨西哥加利福尼亚湾的一个小规模渔业案例研究为例来说明该方法，并表明我们的预测捕捞努力量（PFE）指标，即按当地沿海人口数量调整后的给定区域内每日作业船只数量，能够准确预测加利福尼亚湾的渔业上岸量。将我们的PFE值与整个海湾的商业渔业上岸量进行比较还表明，加利福尼亚湾目前的小规模渔船数量大约是实现理论最大鱼类生物量上岸量所需数量的两倍。我们的方法不依赖渔业类型，可用于定量评估小规模渔业增长的成效。这种新方法为估算全球小规模船队的捕捞努力量迈出了重要的第一步。
