Fishing in the dark : monitoring night-time fishing boat activity in Southeast Asia using satellite data

• Main Author: Tanggono, Victoria Cahyani
• Other Authors: Lee Ser Huay Janice Teresa
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Science::General
• Online Access: https://hdl.handle.net/10356/148500
• Institution: Nanyang Technological University

Despite the global importance of marine resources, their integrity faces threats such as overfishing and illegal, unreported and unregulated (IUU) fishing. Unfortunately, there are few systems for monitoring real-time fishing activity. Without such data, developing effective measures to address overfishing and IUU fishing is challenging. The emergence of a novel Visible Infrared Imaging Radiometer Suite (VIIRS) boat detections (VBDs) dataset has the potential to address this challenge. Covering 101 months of night-time data from April 2012 to August 2020, this project demonstrates the potential utility of using VBDs to examine fishing activities in seven countries within Southeast Asia (SEA): Cambodia, Indonesia, Malaysia, Myanmar, the Philippines, Thailand, and Vietnam. To further demonstrate its potential as a monitoring tool, VBD data is also used to examine illegal fishing in marine protected areas (MPAs), and to investigate the difference in fishing activity within and around MPAs. Descriptive analysis found that VBD fishing activity trends were largely consistent with fishery statistics from other established sources, validating its credibility as a complementary and supplementary dataset. Based on VBD data, fishing activity in SEA increased by 30% from April 2012 to August 2020, which is an average annual increase of 3.6%. This finding is consistent with the global trends of increasing fishing activity, marine fishery production and fishing effort, and the regional trend of increasing marine fishery production. MPA encroachments were found to be common, which is consistent with existing literature that there is generally weak enforcement in the region. Increased MPA encroachments were observed before festive seasons, possibly to increase cash flow for the festivities. There was a 160% increase in MPA encroachments in the Philippines from March to August 2020 relative to the same period in 2019, suggesting that illegal activities grew as the COVID-19 pandemic diverted enforcement resources elsewhere. Results from the spatial analysis were generally intuitive, with fishing activity found to mostly increase with distance away from MPA boundaries. Interestingly, fishing activity was observed to be the highest right outside MPA boundaries in Indonesia, suggesting that MPA establishment might have displaced fishing activities elsewhere. These results show that VBD data has the potential to improve understanding of the region’s spatio-temporal fishing activity patterns, and to support monitoring efforts that are crucial for realising marine conservation objectives in SEA and beyond.