Heal the Bay’s Santa Monica Pier Aquarium will hold its third annual “Underwater Parks Day” Saturday, Jan. 15, with presentations and activities highlighting Marine Protected Areas of Southern California and the benefits of marine reserves around the world.

The event will additionally feature craft projects for all ages and special displays to encourage visitors to help protect the ocean through their everyday actions.

Winners of the aquarium’s underwater photography and video contest will be announced at 2 p.m., and examples of the winners’ work will be on exhibit.

Entries for the contest are being accepted through 5 p.m. Monday, Jan.10. Only one entry per person, consisting of a single image, should be submitted.

Photographs will be judged for subject relevance and artistic vision by a panel of Heal the Bay staff. Winners will be chosen in three categories: open photography, youth photography for those under 18, and video.

Underwater Parks Day has been organized by marine science centers throughout Southern California as a day to educate the public about recently approved Marine Protected Areas, an initiative to preserve and restore California coastal marine resources. Marine Protected Areas, also known as MPAs, are a network of underwater parks established through the state’s Fish and Game Commission and managed by the Department of Fish and Game.

The pier aquarium, 1600 Ocean Front Walk, Santa Monica, will be open regular winter weekend hours from 12:30 to 5 p.m. during the event.

Information, including a schedule of activities, www.healthebay.org/event/underwater-parks-day.