Fishing and habitat area for the sea cucumber Isostichopus fuscus (Ludwig, 1875) in the Galapagos Marine Reserve

The sea cucumber (Isostichopus fuscus) fishery was the most important in the Galapagos Marine Reserve (GMR) in the 2000s. However, after sustained over-fishing that has limited its recovery capacity, this small-scale fishery is nowadays commercially collapsed in the Galapagos. Under that scenario, the Galapagos National Park (GNP) called for total closure from 2016 to 2021. At the end of this period, if the fishery is re-opened, a total allowed catch must be established on the basis of the calculation of the species abundance. In order to estimate the abundance, a spatially explicit fishing and habitat area model was created within the boundaries of the GMR. This model was created on the basis of the ecology of the species (mostly found on rocky bottoms) and the diving depth limits (from 0 to 30 m). We considered benthic cover data from two sources, the sea-cucumber monitoring program data and the cover estimated from video data at 344 locations scattered throughout the GMR. We then filled the remaining areas with remote sensing habitat classification data. All areas not covered by the previous sources of information were assumed to be rocky bottoms. Since mangrove forests (Moity et al., 2018, 2019) are not an optimal habitat for I. fuscus, we removed them from the model. We also removed the no-take zones (Zoning 2000, Moity, 2018a, 2018b) since no fishing is allowed in those areas. The total fishing and habitat area for I. fuscus was calculated in 272.1 km2. […]

海参（Isostichopus fuscus）养殖业曾是20世纪在加拉帕戈斯海洋保护区（GMR）中最为重要的产业。然而，由于持续的过度捕捞，其恢复能力受限，如今这一小规模养殖业在加拉帕戈斯已陷入商业性的崩溃。在此背景下，加拉帕戈斯国家公园（GNP）自2016年至2021年呼吁实行全面关闭。在该期限结束后，若渔业重新开放，则必须依据物种丰度的计算确定总允许捕捞量。为了估算丰度，我们在GMR范围内构建了一个空间明确的捕捞和栖息地面积模型。该模型基于物种的生态学特征（主要分布在岩石底部）以及潜水深度限制（从0至30米）。我们考虑了来自两个来源的底栖覆盖率数据，包括海参监测项目数据和从GMR内分布的344个地点的视频数据估计的覆盖率。然后，我们用遥感栖息地分类数据填补了剩余区域。所有未涵盖的前述信息来源的区域均假定是岩石底部。鉴于红树林森林（Moity等，2018，2019）并非I. fuscus的理想栖息地，我们从模型中将其去除。此外，我们移除了禁渔区（Zoning 2000，Moity，2018a，2018b），因为这些区域不允许捕捞。I. fuscus的总捕捞和栖息地面积计算为272.1平方公里。