Lots of traffic in this area. Anyone have an idea what's going on so far offshore?
My guess, they're those AIS buoys they attach to their nets. The coloured vessels say "fishing", the rest are "unspecified vessel"
whats interesting is that theres something in that area recieving the AIS and pushing it out to the internet.
Select to expand quoteJonE said..
whats interesting is that theres something in that area recieving the AIS and pushing it out to the internet.
Low-flying satellites at about 400km which do pick up AIS. That's my understanding.
Select to expand quoteJonE said..
My guess, they're those AIS buoys they attach to their nets. The coloured vessels say "fishing", the rest are "unspecified vessel"
whats interesting is that theres something in that area recieving the AIS and pushing it out to the internet.
I've encountered this sailing off the East coast. There was a heap of AIS signals showing up along the edge of the continental shelf. They are unregistered AIS devices used by fishers to track nets. You can buy them in bulk for about $50-$100 each. So far as I am aware, they are illegal, which is why they tend to be used in international waters and not closer to shore. The MMSI numbers are generally not issued by a recognised authority. Another problem with them is that AIS uses just two frequencies and time division multiplexing, which means there is a limit to the number of signals that can be sent/received in proximity to each other in a given period of time. If this is exceeded, then signals clash and information is lost. As I understand it it is already the case that in busy areas such as the English Channel, there are so many vessels sending signals that signal clash occurs and vessel position information is lost. Proliferation in using AIS for fishing nets can adversely effect the original use of AIS, for safety of vessels at sea.
Tuna longliners have been using them for years. These lines are often 25+nm long. AIS beacons along the line help the fisherman check on how straight the line is and aid in separating the line when they have to let ships pass through.
I agree the horse has left the barn some time ago. FWIW, I think AIS needs a re-design/upgrade so there is a legal, recognised, dedicated channel for fishing net buoys keeping them clear of the frequencies used for vessels. And the set up for vessels needs to enable more simultaneous signals, and address some of the current challenges for satellite AIS, which as I understand it currently relies on various workarounds. I suspect an issue would be loss of backward compatibility and so the need to upgrade AIS transceivers worldwide - not cheap tho' the vendors would love it. Bit like the compulsory move from analogue to digital mobile phones back in the early nineties.
I don't believe there is anything out there apart from MH370. When you zoom in it's showing yachts, tugs,fishing boats , high speed vessels, ships...etc even in 60 knots blows. Also no tracks coming or going from Perth. I think it's just some type of dump marine traffic is using for lost icons on there app.
