SWAMPWALK GRAND OPENING. Saturday, May 18, 10 a.m., rail trail entrance, Route 97, Wenham. Open Space & Recreation Committee hosts at the north entrance to the boardwalk. Refreshments served. Rain or shine. Prizes awarded for observing an off-the-endangered-list spotted turtle and any member of the three beaver families.
BIODIVERSITY BY THE SEA: EXPLORING BEVERLY’S TIDE POOLS. Saturday, May 18, 11 a.m. to noon, Lynch Park, 55 Ober St., Beverly. Meet and learn about the strange and surprising creatures inhabiting these miniature seas with naturalist Paul Erickson, a former New England Aquarium staffer and “Good Morning America” special correspondent. All of the animals investigated will be returned to their natural habitats. Children must be accompanied by an attentive parent or guardian. Bring warm footwear that will keep feet dry and stable on slippery rocks. Park in parking lot and gather at the seawall entryway to the beach. Free; part of Beverly Open Space and Recreation Committee’s Earth Day nature walks. Rain or shine.
MAYOR’S RIDE. Saturday, May 18, 2 p.m., Beverly City Hall, 191 Cabot St., Beverly. Join Mayor Bill Scanlon, the Bicycle Beverly Committee, and River House for the second annual bicycle ride, to Hospital Point Lighthouse and back. Participants of all ages and all cycling abilities invited. The easy, scenic route will be marshalled for safety and concludes with Hoodsies and additional refreshments back at City Hall. Donations for River House will be accepted. 978-927-4599.
BIRD PHOTOGRAPHY 101. Sunday, May 19, 8 to 9:30 a.m., Ipswich River Wildlife Sanctuary, 87 Perkins Row, Topsfield. Join Nancy Landry, avid bird photographer and author of “The Birds of Plum Island Calendar,” for a walk, during which she will share tips for finding and photographing birds. Bring either a digital single lens reflex camera or a “point and shoot” type camera with an electric view finder and minimum 10X zoom lens. Binoculars and a birding guide are suggested, but optional. Limited to 10. $12/adult, $10/Mass Audubon members. Advance registration required at 978-887-9264.