Extracted from excitinghistory.com:
Botters are fast fishing sailboats designed to operate in shallow waters. They have a flat bottom and a pair of retractable side-mounted stabilizers. The botters have a storage compartment on board for fish; it allows fresh water to flow through small holes in the hull. Sails are rarely raised unless there is a festival, as in the last three photos. The sails are brown from weather-resistant disinfectant.