While rays live alone for most of the year, they gather during breeding or migration into groups known as fevers, which number in the hundreds and sometimes thousands. Mobula rays, like those captured in an aerial view by Laura Leusko off the coast of Baja California Sur, Mexico, demonstrate a timeless behavior while reminding us that industrial fishing and pollution continue to take a toll on marine wildlife globally.

Ocean Photographer of the Year (previously) highlights what makes our planet’s largest bodies of water so spectacular—and so critically in need of protection. Co-presented by Oceanographic Magazine and Blancpain Ocean Commitment, the annual competition invites amateur and professional photographers from around the world to share images showcasing the spectacular wildlife, cultures, scientific inquiry, and conservation efforts in and around our oceans.

This year’s submissions include images of dramatic encounters, maritime history, enduring cultural traditions, the violent and critical effects of human actions, and significant restoration efforts. From Mizael Palomeque Gonzalez’s up-close view of a spotted eagle ray to Celia Kujala’s distressing photo of a polar bear with a piece of plastic in its mouth to Tobias Friedrich’s interaction with a sunken ship, the finalists’ images survey the diversity of our oceans and the urgent need to conserve their fragile ecosystems.

See some of our favorite photos here, and keep an eye out competition’s website and Instagram, where winners will be announced on September 12. An exhibition is also slated to open on November 28 at the Australian National Maritime Museum in Sydney before it travels to several more venues.