There is no legal term "reasonable cause". There is "reasonable suspicion" ,(RS), which pertains to the belief of an officer of the law that a crime may have been committed, is about to be committed, or some other "articuable facts" giving the officer reason for a detain and stop, example being some guy in a dark alley behind a business at night.

Probable cause, (PC), is where there are facts and circumstances that support an arrest, example; eyewitness testimony, physical evidence, etc.

Implied consent is where you agree to something automatically when you get a license.

Kickmeter,

Officers only need RS for a detain and stop, not PC. State a legal precendent to prove me wrong.

The implied consent as it relates to hunting and fishing comes partly from signing your license, and also from RCW 77.15.470. Basically they say that you will submit to an inpection of your equipment. How do you inpect a cooler? Look inside.

Bob,

Regardless if it sounds to "copy", those are the rules. It opens the door for further scrutiny.
Let them look in you cooler, at your boat, check you gear, etc. You might just be sorry if you don't. I don't hide anything, so I have no worries. If I screw up, I take it like a man and that has gotten me out of more infractions (traffic) than excuses, defiance, or beligerence.

G-man,

WDFW are fully commission officers and can enforce all laws enacted in the state or Washington including Titles 9, 9A, 46 (traffic), etc., along with enforcing dept. of health regs relating to aquaculture.

Andy

P.S. Now if they want to inspect the boat that you use as your residence that opens up a whole other can o' worms.