I would guess a popular fishing spot since most of the boats in the area now states "fishing". The location does not update very often, too far from land and recievers most likely. The popup says location recieved by satelite somewhere between 3 hours and 20 minutes ago.

I think it's just delayed to make this free preview useless for most commercial applications. They sell this data after all.

That area is close to where the San Diego long range fishes for big 200lb plus yellowfin and wahoo. It may be ling liners doing the same.