More than 80% of the ocean remains unmapped, outside the scope of easy human familiarity. But within the mapped 20%, and even in the uncharted zones, flashes of what exists, the beauty and strangeness, are enough to make you stop in wonder. 

This year's World Oceans Day photo competition captures the vivid grandeur and vast complexity of marine life. Hosted by the United Nations for the ninth year in a row, with support from Oceanic Global, thousands of photographers submitted images for six categories: revitalization, above-water seascapes, underwater seascapes, nature-based solutions and ocean exploration, ocean critters, and coastal communities. 

The winners, selected by a team of wildlife photographers, cover a wide range of subjects. There are close-ups of rare animals, broad sweeping shots of marinescapes, images from benevolent dives, and intimate portraits of communities reliant on the ocean. 

Collectively, they remind us that Earth is called the "Blue Planet" for a reason.

All life on Earth originated in the ocean, and all life depends on the ocean for survival, whether its through nourishment, oxygen, or some form of environmental support. But as the planet warms from greenhouse gas emissions, the ocean is becoming hotter and more acidic, making waters inhospitable to marine life. On top of this deteriorating baseline, the ocean is filling with plastic waste, chemical toxins, and wastewater.

The primary cause of all this harm? Human actions. That means it's within our capacity to stop it and to shield the ocean from future devastation, going even further to support its broad recovery. 

To that end, the UN is calling on countries to protect at least 30% of land and marine spaces by 2030.  

The photos from this year's World Oceans Day contest show all that we stand to lose if we fail in this basic responsibility — but they also show what we can preserve for future generations if we rise to the challenge.  

Here are some of the highlights from this year's contest.

Underwater Seascapes, 1st Place

Image: Nicolas Hahn, Argentina

"A Diamond Stingray and a one-eyed Porcupine fish search for a meal in the sand as hundreds of Big Eye Jacks school behind them. The incredible biomass in the Cabo Pulmo National Park (Baja California Sur) allows for some surreal sights. Protected areas such as these serve as a strong example of how plentiful our oceans can be when given the chance to recover." —Nicolas Hahn, Argentina

Above-Water Seascapes, 1st Place

Image: Nguyen Vu, Cao, Vietnam

"In every profession we can find challenges but also beauty. When the fishermen head out on the water, they hope to return with boats full of fish and shrimp out of necessity. I simply want to convey the beauty of the art of fishing with seine nets in my homeland." —Nguyen Vu, Cao, Vietnam

Coastal Communities, 1st Place

Image: Supachai Veerayutthanon, Thailand

"Bajau, for many generations, from birth to death, from young to old, they spend their entire lives on their boats. They are not citizens of any state. The sea is their birthplace and their only home on Earth." —Supachai Veerayutthanon, Thailand

Nature Based Solutions and Ocean Discoveries, 1st Place

Image: Giacomo d’Orlando, Italy

"Adriana Campili, marine biology researcher, checks the status of the Reef Aquarium inside the laboratory of the Australian Institute of Marine Science. The AIMS is the most specialized authority in charge of the Great Barrier Reef’s monitoring conditions. Inside its Sea Simulator, the most state-of-the-art experiments are carried out on corals, aimed to secure a future for our reefs.

In this image, I wanted to depict the tight connection between the human being and the marine ecosystem, underlining the importance of this natural bond." —Giacomo d’Orlando, Italy

Ocean Critters, 1st Place

Image: Viktor Lyagusskin, Georgia

"Caprellas, also known as skeleton shrimps, are very funny and tiny animals. They grow to a maximum of 6 centimeters long. They are very social and active, eating nonstop and fighting with each other. The ‘spaceship’ is a Bolinopsis infundibulum, common northern comb jelly. Bolinopsis don’t sting but are carnivorous and eat everything they catch, even other comb jellies. In my image, it is floating under the ice." —Viktor Lyagusskin, Georgia

Revitalization, 1st Place

Image: Aunk Horwang

Image: Aunk Horwang, Thailand

Image: Aunk Horwang, Thailand

"Ghost nets are one of the deadliest forms of marine pollution in the Thai oceans. On frequent occasions the ghost fishing nets entangle large marine creatures like this manta ray. This can be life threatening to them if not rescued, for example by a diver." —Aunk Horwang, Thailand

Global Citizen Life

Defend the Planet

9 Winning World Oceans Day Photos That Show the Surreal Beauty of Marine Life

By Joe McCarthy