Beaver Fun in the Setting Sun. Ipswich River Wildlife Sanctuary. Topsfield. 5:00 p.m. to 7:00 p.m. See beaver lodges and dams, chews, scent mounds, and, if we are very quiet, maybe even a real live beaver! For families with children 6 and older. Rain or shine. Registration required. $10 adults, $8 children (discount for members). 978-887-9264.