The organization that oversees the nation’s oldest wildlife sanctuary is holding Oakland’s first nature festival in decades.

The celebration will be all day Sunday, starting bright and early on the shores of Lake Merritt at the Rotary Nature Center.

The Oakland Nature Festival’s theme is spreading knowledge and understanding of the ways people interact with nature. It starts at 8 a.m. Sunday with a lecture and bird-sit called “Bird Language, What the Birds Are Saying.”

“We go out to the garden and listen to the birds. Even with all the background noise, there’s still a lot to learn,” said festival organizer Constance Taylor, a naturalist at the nature center.

The center oversees the Lake Merritt Wild Duck Refuge, established in 1870.

“Once you really tune in to hear what the call means –- territory, juveniles begging for food, warnings, mating calls – you can tune in to the environment,” she said. “Animals really pay a lot of attention to bird calls.”

Meghan Walla-Murphy will lead that event, at the nature center at 600 Bellevue Ave. But the free festival really gets under way at 10, when vendors, community organizations, kids’ activities leaders and everyone else begins to arrive.

Fifteen minutes later, at the outdoor classroom, you can learn how to get honey from a hive, courtesy of the Alameda County Beekeepers Association. Fifteen minutes after that, there is a bird walk.

At 11 a.m., naturalist and wildlife illustrator John Muir Laws will lead a waterfowl illustration workshop, and Devin Schaefferkoetter will give a presentation on Bay Area Mushroom Basics at 11:30 a.m. and 12:15 p.m.

Author Mary Ellen Hannibal will discuss her new book, “Citizen Science: Searching for Heroes and Hope in an Age of Extinction,” at 12:15 p.m., with copies available for purchase.

“We want people to learn about human impact on wildlife,” said Stephanie Benavidez, supervising naturalist. “It is important to balance recreational needs with the needs of wildlife.”

The festival will coincide with the return of migrating birds. “This is a great time of year for people to visit Lake Merritt,” Taylor said. “We are commemorating the return of our feathered guests, as birds migrating along the Pacific Flyway stop here for the winter.

“There’s a huge amount of bird diversity here, right in the heart of Oakland,” she said. “Lake Merritt is still a functioning estuary, a very special ecosystem in the middle of the concrete jungle.” It even is home to leopard sharks, though there is no guarantee those at the festival will see any, she said.

But they can view turtles and tortoises from the Rotary center from 12:30 to 2:30 p.m., owls from the Lindsay Wildlife Experience from 1:30 to 2:30 p.m., followed by Owl Pellet Dissection.

At 11:30 a.m., naturalists will lead an exploration of marine life and critters that live in Lake Merritt. There is a plant walk at 1 p.m. and a Lake Merritt history walk at 2:15 p.m.

Vendors, artists, community and environmental groups and schools will have information tables around the center and host child-friendly activities such as arts and crafts overseen by Children’s Fairyland and the Junior Center for Art and Science, and foam archery.

Also for the kids, author Kamaria Lofton will read from her “My City Is Oakland” book and entertain on guitar. It all winds down with Marly Peifer’s demonstration on the finer points of drawing skulls, at 2:45 p.m.

Guests will be able to bid on silent auction items. Donations and proceeds will help fund equipment such as binoculars for public use at the center and museum display upgrades. The silent auction will benefit the San Francisco Chapter of the Wildlife Society, co-organizer of the festival.

A schedule can be found on the Oakland Nature Festival website at https://tinyurl.com/oakland-nature-fest. For more information, contact Constance Taylor at 510-238-3739 or rotarynature@oaklandnet.com.

Contact Mark Hedin at 510-293-2452, 408-759-2132 or mhedin@bayareanewsgroup.com.

Oakland Nature Festival

When: 8 a.m.-4 p.m. Sunday (bird language workshop at 8 a.m.)

Where: Rotary Nature Center, Lake Merritt, 600 Bellevue Ave., Oakland

Details: https://tinyurl.com/oakland-nature-fest