Port Stephens Fisheries Institute, NSW Department of Primary Industries, Nelson Bay, NSW, Australia.
PLoS One. 2019 Jan 8;14(1):e0209926. doi: 10.1371/journal.pone.0209926. eCollection 2019.
One role of Marine Protected Areas is to protect biodiversity; however, illegal fishing activity can reduce the effectiveness of protection. Quantifying illegal fishing effort within no-take MPAs is difficult and the impacts of illegal fishing on biodiversity are poorly understood. To provide an assessment of illegal fishing activity, a surveillance camera was deployed at the Seal Rocks no-take area within the Port Stephens-Great Lakes Marine Park from April 2017-March 2018. To assess impacts of illegal fishing activity in the no-take area, Baited Remote Underwater Video Systems (BRUVs) were used to quantify abundance and size of snapper Chrysophrys auratus from 2011-2017. BRUVs were also deployed at two nearby fished locations and two other no-take areas to allow comparison. Over 12 months of camera surveillance, a total of 108 recreational vessels were observed illegally fishing within the no-take area (avg 9.0 ± 0.9 per month). The greatest number of vessels detected in a single month was 14 and the longest a vessel was observed fishing was ~ 6 hours. From 2011-2017, the abundance of C. auratus within the Seal Rocks no-take area significantly declined by 55%, whilst the abundance within the other fished areas and no-take areas did not significantly decline over the same period. Lengths of C. auratus in the Seal Rocks no-take area were significantly smaller in 2017 compared to 2013 which was driven by a decline in the number of legal sized fish over 30 cm. Based on mean number of illegal fishers per vessel recorded in the no-take area, and an allowable bag limit of 10 C. auratus per person, it is possible that more than 2,000 C. auratus are removed annually from this no-take area. There is a strong likelihood that illegal recreational fishing is causing a reduction on a fishery targeted species within a no-take MPA and measures need to be implemented to reduce the ongoing illegal fishing pressure.
海洋保护区的一个作用是保护生物多样性;然而,非法捕捞活动会降低保护的效果。量化禁渔区内的非法捕捞努力是困难的,而且非法捕捞对生物多样性的影响也知之甚少。为了评估非法捕捞活动,2017 年 4 月至 2018 年 3 月,在斯蒂芬斯港-大湖海洋公园内的海豹岩禁渔区部署了一个监控摄像机。为了评估禁渔区内非法捕捞活动的影响,从 2011 年至 2017 年,使用诱捕式水下视频系统(BRUVs)来量化笛鲷 Chrysophrys auratus 的丰度和大小。BRUVs 还被部署在两个附近的捕捞区和两个其他禁渔区,以便进行比较。在 12 个月的摄像机监测中,共观察到 108 艘娱乐船在禁渔区内非法捕鱼(平均每月 9.0 ± 0.9 艘)。一个月内检测到的船只数量最多为 14 艘,船只被观察到捕鱼的最长时间约为 6 小时。从 2011 年至 2017 年,海豹岩禁渔区内 C. auratus 的丰度显著下降了 55%,而同期其他捕捞区和禁渔区的丰度没有显著下降。2017 年,海豹岩禁渔区内 C. auratus 的体长明显小于 2013 年,这是由于 30 厘米以上合法尺寸鱼类数量的减少所致。根据禁渔区内每艘船记录的非法渔民平均人数,以及每人允许捕捞 10 条 C. auratus 的规定,每年可能有超过 2000 条 C. auratus 从这个禁渔区被捕获。很有可能是非法休闲捕鱼导致了禁渔区目标鱼种数量的减少,需要采取措施来减少持续的非法捕鱼压力。