First is the fishing licence fee (about $60.00/yr for a resident/$133.00 for a non-resident), LOTS of free labor from fishing clubs/etc., and the help of the Oregon State Patrol (State Police if you will) and County Sheriff's Departments.
Where OSP/Sheriffs comes into play is they do the majority of game checks, respond to 'I'm looking at a 'no-no' call, etc. Very few actually Game Officer's Statewide, but all the above folks are local so a response is pretty damned quick.
Not had to make the call very often since 1996 (when I moved to Oregon) but the longest wait I've had for a Officer was about 15 minutes ... and I was really out in the 'sticks' at the time. Actually so far off the cell phone grid I had to knock on a door and ask if the folks had a land line I could do a 911 (your 611?) call. None emergency, but a free call and they shift you right over to the proper phone line.
Can't speak to the OSP, but every Sheriff's Department has high speed boats and 'drift boats' they can run the river or lakes if need be. Some times that 'need be' is lets do a run on a lake/river and see what we shall see. Interesting to be fishing in the middle of nowhere and have your license checked by a Uniformed (and well armed) Officer. NO ONE says 'no, don't think I want to show that to you.'
fae