This may be more pronounced, but this has been going on for at least 15 years and probably longer. I only say 15 years because that is how long I have been working with satellite imagery that easily shows these boundaries. They show up as obvious lines of light in nighttime visible satellite imagery.

“What are they intending to do with this capability?”, I asked when going to read the archived link.

The masses of the smaller boats could also act “as missile and torpedo decoys, overwhelming radars or drone sensors with too many targets,” said Thomas Shugart, a former U.S. naval officer now at the Center for a New American Security.

This seems a reasonable explanation. Provide cover for those who must travel undetected. Obstruct those who must be prevented from traveling or seeing stuff.

A mass of fishing vessels loitering some miles away may actually blind a surface-based radar to things beyond them. Too much reflective metal, one would have to dial down sensitivity or only look high.

They could do worse, though - they could add wind generators to fishing boats for Doppler effect. Radars look for quick moving objects by detecting Doppler shift. The tips of wind generators move at drone-like speed.

Don’t they also do this with fishing vessels somewhere in international waters near South America? I read somewhere that there’s so many of them that they light up the night sky.

Anyone got a non paywalled source?

Did they have a word count to fill?