Shoreham has several fishing marks, the most obvious being the Harbour Arms. But there is good Mullet fishing in the River Ardur. I have personal experience of fishing the Western Arm. This is easy to get to with a nearby car park. The fish I have caught here are Rockling, Pouting, Whiting and Flounder.
Bait is available locally from Lagoon Bait and Tackle 01273 415879