Just to add 2 cents
Not sure if I know what I am talking about but using my leagal hat.... In the deleware I think Jim is right on. As long as you do not beach in PA, you can fish the whole river following NJ regs if you took to the water in NJ and have a NJ license.
The bay is another matter. You can definitly catch fish in NJ, appropriately so, and drift into NY and get busted if regs / seasons openings are different. "intent" is not required to violate the law. As far as the boundaries I use the bouy as general markers. True, you could be off, but, in general the police wont bother you if you are within the general area.
I know this does not make you feel great but I think Jims initial comment would end up being the reality. Where you berth is where they are generally going to check your fish.
Hope this helps