ST. MARY’S AND NASSAU RIVERS from Hilliard, go north on US 301 for 7.0 miles to Boulogne city limits sign. Go 1.1 mile to Lake Hampton Road, turn right, and go 0.7 miles to an unnamed graded road. Turn left and go 0.5 miles to the ramp. Single-lane ramp with paved parking lot capable of accommodating 20 vehicles. Picnic facilities are available and bank fishing is allowed. This 125-mile river starts in the acid swamps of Okeefenokee and becomes a tidal river below US 17 north of Jacksonville.
St Mary’s and Nassau River fishing is redbreast sunfish and small largemouth bass territory. The salt marsh zone is famous for striped bass (the same is true for nearby Nassau River). These rivers give anglers the opportunity to catch a variety of freshwater species. In the upper reaches of these rivers, black bass, bream, and catfish can all be taken. As water temperatures drop, bass will start to congregate in deeper pools. This makes it easier for anglers to target prime fishing spots where bass will be hanging out. Targeting cypress stands along river shorelines is also a great way to locate largemouth bass. During the fall, month’s striped bass will enter the Nassau River and the fishing can be quite good in areas around the I-95 bridge.
Lead-heads rigged with a plastic tail are an effective way of taking striped bass. Anglers looking to catch marine species such as drum, sea trout, and flounder will want to focus on the lower stretches of the river. Live bait is an effective way of taking these species, with mud minnows, shrimp, and crabs being popular choices.
More great links to information on these rivers, http://en.wikipedia.org/wiki/St._Marys_River_%28Florida-Georgia%29