There are SOME waters where the fishing actually gets better with some boat traffic...but for the most part, fishing generally does shut down with a lot of traffic, and a person has only these options (MOST already mentioned)...
1. Fish EARLY morning. If you can, launch a few minutes before 1st light.
2. Fish evening. MOST of those folks will be drinking somewhere at that point...HOPEFULLY not on the water.
3. Fish at night...prepare for bugs and have good lights.
4. Find spots like underwater islands, creek arms and coves that the pleasurecraft HAVE to avoid.
5. Fish the middle of the week when everyone else is at work.
6. Find other waters in the area that may not be so crowded.
Life Member David BB Linkmeister
US Army '78-'85
West Coast Member of da EH! Team
Kangaroo Kounty Razzer-in-Chief