Author：Chen Wen-Yu and Chiu Wen-Yu, COA’s Fisheries Agency; Fu Chia-Chi, Overseas Fisheries Development Council of the Republic of China (OFDC)
The continuous population growth and limited land on earth have made marine resources ever more important and the increasing keen competition has also involved political elements in fishery management to make things even more complicated. In terms of the issue of global fishery resources, the NGO Tuna Forum has advocated for strict regulatory actions on harvest strategies, fish aggregating devices (FADs), bycatch limits, harvest monitoring and control, etc. in order to solve the issue of sustainable fishery. The specific observation measures are taken through on-board observers and electronic monitoring to enhance the fisheries monitoring, control, and surveillance (MCS) and include: (1) 100% coverage of on-board observers on purse seine fishing vessels, (2) at least 5 % coverage of on-board observers on longline fishing vessels, subject to change to 100% coverage within five years in case of any confirmed violation, (3) 100% coverage of on-board observers on implementation of a transfer at sea, with all necessary data collected and transmitted to relevant agencies in a timely manner.
According to the 2016 statistics published by the Food and Agriculture Organization of the United Nations (FAO) in 2018, the catch yield of Taiwan is 750,000 metric tons (ranked 21 in the world), indicating the inescapable responsibilities for fisheries sustainability. With the limited number of on-board observers available, advanced monitoring technologies are used to maintain monitoring, control, and surveillance to meet the demand of the trend of traceable production, including those of monitoring and surveillance, intelligent machine devices, Internet of Things (IoT), big data analysis, etc. With integrated electromechanical engineering technologies, the electronic monitoring system is built as a part of the smart fisheries management system, in which big data analysis is also implemented to track the flow of fishing products, so as to realize smart fishery production and management and enhance the competitiveness of Taiwanese fishing industry.
Current Development Status and Future Planning of the Electronic Monitoring System (EMS)
(1) Current Development Status of the Electronic Monitoring System (EMS)
The main functions of the EMS are two-folds, one of which is "data collection for scientific assessment" which ensures the accuracy of statistical data for a better understanding of the operations of fishing vessels, and the other one is "mandatory compliance management" which ensures that the vessels comply with regulations of different sea areas (management organizations). The system has the advantages of improved data quality and lower overall costs. Shortcomings, however, include the technical instability, high maintenance and initial costs, and the heterogeneous specifications of fishing vessels/fisheries to be overcome (Table 1).
The development of the electronic monitoring system has met with many challenges. It has not yet clarified whether the electronic monitoring system is to replace or supplement the on-board observers or to improve the coverage rate. There are also the problems of the privacy of the crew members and whether the information collected by the on-board observers is independent and correct. The information is crucial for regional fisheries management organizations (RFMOs) to validate the fishery statistics reported by the vessel captains.
(2) Research and development of smart agriculture in the electronic monitoring system
In 2017, in conjunction with the Smart Agriculture Program of the Council of Agriculture, Dr. Kuo Yen-Fu (National Taiwan University) and Dr. Chen Yung-Yu (National Cheng Kung University) jointly developed the “Electronic Monitoring System with Identification Functions” to install on small-size longline fishing vessels which do not have on-board observers. The system has functions of "automatic fish species identification", "fish length measurement", "operation event log", "Redundant Array of Independent Disks (RAID)" and "harvest location information", which record the species and length of the fish, the time and location (latitude and longitude) of harvest, and relevant information of the fishing vessels, etc. The structure of the electronic monitoring system is shown in Figure 1. The self-developed system has been installed on four fishing vessels for experiment.
Among the technologies used, the fish species identification system is developed using deep learning to build a model to automatically identify eight common catches in longline fishery, including albacore (Thunnus alalunga), bigeye tuna (Thunnus obesus), yellowfin tuna (Thunnus albacares), southern bluefin tuna (Thunnus maccoyii), black marlin (Makaira nigricans), sailfish (Istiophorus platypterus), swordfish and mahimahi (Coryphaena hippurus). Pictures taken by on-board observers on fish species are used for the training system.
The average accuracy of fish species identification reaches 95.82% at 7.81 milliseconds each frame. The Mask Regions with Convolutional Neural Network (Mask R-CNN) technology is used to detect the fish body (Figure 2), reaching 94.54% fish detection rate. The proportionate scale is first calculated by using the color pattern from images. The actual fish length is calculated by applying the proportionate scale on the distance between the snout and the fork. In the fish images without color pattern, the post-calibration fish length measurement error is only 4.63%.
The development of the electronic monitoring system in Taiwan is based on cooperation among the industry, government and academia, following planned phases and slowly accumulating the power of management in the long run. If it can be substantially implemented in the future, we will be more active in fulfilling our obligations to the international community. It is hoped that the R&D of the electronic monitoring system will strengthen the scheme of fisheries monitoring, control, and surveillance (MCS) in Taiwan, enhance the international image, and further consolidate the capability in deep sea fisheries.
