Grand Bay is a coastal saltwater bay located on the border of Alabama and Mississippi, forming part of the northern Gulf of Mexico. The paddling experience here is characterized by extensive marshlands, tidal bayous, and a network of waterways within the Grand Bay National Estuarine Research Reserve. The area is known for its rich biodiversity, serving as an essential nursery habitat for fish and home to several rare plant and animal species. Paddlers can explore the upper reaches of Bayou Heron, a notable waterway that flows into the bay from the Moss Point, Mississippi area, offering a route through maritime forests and marshes. The overall environment is a mix of pine savannas, freshwater marshes near the boardwalk trails, and saltwater influences closer to the open bay.

Key public access for paddlers includes the Bayou Heron Landing, which provides a launch point for exploring Bayou Heron. The Grand Bay Coastal Resources Center, located at 6005 Bayou Heron Road in Moss Point, Mississippi, also serves as a focal point for the reserve and may offer access. The Savanna Trail Boardwalk leads from this center to a freshwater marsh. Given the coastal nature, paddlers must be mindful of tidal currents and plan trips accordingly; paddling against a strong outgoing tide in confined bayous can be challenging. The area is exposed to winds from the Gulf, which can create chop, especially over open water sections of the bay. Boat traffic may be present in main channels. Summer brings heat, pop-up showers, and significant insect populations, necessitating sunscreen, bug spray, and ample drinking water. The best seasons for paddling may align with spring and fall bird migrations, which are particularly active in the area's oak groves and marshes. Wildlife viewing is a major draw, with opportunities to see ospreys, bald eagles in winter, and a variety of warblers and other migratory birds. The water is generally calm in protected bayous but can become rough in the open bay during weather events. Facilities are limited to basic public boat ramps and parking areas; the Coastal Resources Center has public hours but access to the boardwalk may be available outside those times via a gravel pathway.