In Australia, one would not say 'I see the fisherman IN the harbour' as that would imply they were in the water. If they were in boats, then one would then say: 'I see the fishing boats in the harbour', not 'the fishermen.' If one is talking about seeing fisherman standing on the wharves fishing, that would be 'at' the harbour, not 'in' the harbour.
Likewise, in USA one would say "at the port" not "in the port" unless it were indoors. While airports are typically inside, sea ports are not, generally speaking.
I might be wrong but I think this is the difference between "some" and "the".
the audio sounds like "vedo del pescatori nel porto" - have reported it.
do not play tricky dicky with me and mark me wrong for selecting "port". If you are going to spring "harbor" on us, then teach before correcting!