Detecting Fishing Trawlers on open seas

Bottom trawlers in Asia cause significant damage to marine areas including protected marine areas. Wonder if it is possible to detect presence of trawlers in open seas off the coast region of southeastern countries of Cambodia, Thailand, Malaysia.

The size of bottom trawlers tends to be quite small ( 40 to 60 feet wide and 8 to 10 feet tall) and doesn’t have radar reflectors or any AIS system per se.

There is data by Global Fishing Watch, you might be interested in their methods to detect fishing vessels which have their AIS systems turned off.

Namely you can use night lights and SAR data to detect fishing vessels. The GFW page in general might be a good starting point for you to read about methods which are already applied.


Thank you for the suggestions. I have just started looking at GFW and understanding its methodology.

However the local trawlers are often smaller than what GFW tracks, they also do not use any AIS or radar reflectors so they go unnoticed.