Naturalist Patrick McMillan, host and co-director of SCETV “Expeditions,” will give a free talk called “Nature on the Move” at the Sewee Visitor Center at 7 p.m. Saturday.

McMillan also will lead two tours to Bull’s Island Sunday. The tours leave Garris Landing at 9 and 10:30 a.m. Each tour costs $75 and includes a bag lunch.

The tours are sponsored by Coastal Expeditions and will raise money for Cape Romain’s loggerhead sea turtle program.