G'day mate.
I know what you mean about the backpackers. We were camping at Dundaburra one year and came back to our camp site to find our camp table infested with a swarm of backpackers. I let them finish their lunch then told them to f!#k off.
That weed seems to be there the same time every year, and makes it pretty hard to fish. Good to hear you got onto a few though.
Cheers,
Lunatic