Tarpon congregate and spawn out of passes along most of the entire rim of the Gulf of Mexico. The massive attraction to Boca Grande Pass is unknown and subject to many theories. In the spring, it appears that many of the fish's habits all along the coast are in orientation to Boca Grande Pass. With depths reaching near , it is the deepest natural pass in Florida. It is the only major outlet of Charlotte Harbor, which is fed by two major rivers, the Peace and the Myakka. As the bottleneck of the harbor, the currents are strong and serve as an underwater highway for many species of fish and bait.