Coming on the same day that President Barack Obama designated a massive expansion of a marine reserve in the Hawaiian Islands, the Russian government has expanded the Russian Arctic (Russkaya Arktika) National Park to include Franz Josef Land, the world's northernmost chain of islands.

Made up of more than 190 islands, Franz Josef Land is a mostly uninhabited area that is encased in sea ice for much of the year. Yet the rocky, glaciated islands are home to stunning biodiversity. The newly expanded park will protect habitat for such species as the Atlantic walrus, bowhead whale, polar bear, narwhal, and white gull.

Russia's park expansion was signed by Prime Minister Dmitry Medvedev Friday and increases the size of the protected area by 28,500 square miles (7.4 million hectares). At 34,000 square miles (8.8 million hectares), the park is now the largest in Russia.

The park "will contribute to the integrated conservation of the pristine islands and marine ecosystems of the northeastern part of the Barents Sea," the Russian government said in a statement. This includes "glacial and periglacial landscapes of the polar deserts and ecosystems of offshore shallow water and sea ice, [home to endemic] Arctic fauna."

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"This historical national park designation has shown Russia's commitment to the conservation of the Arctic environment, and sent a powerful signal to the other Arctic nations," says Enric Sala, a National Geographic Explorer in Residence who led a Pristine Seas scientific expedition there in 2013.

"Franz Josef Land is one of those few places where one can see what the world would be like without humans," Sala adds. "It's one of the wildest and most beautiful places I have seen, and dived, in my life; and one of the most precious natural jewels in the Arctic." (See photos of some of the unique sea creatures that live there.)

Sala's expedition co-leader, Paul Rose, adds that the timing of the Russian and American announcements this week proves that "we're in a sweet spot for ocean conservation at the moment. People are seeing the success of marine protected areas around the world and they want to do it themselves. We're also in a time of healthy competition for ocean leadership."

The new park designation is particularly important because the Arctic is changing at unprecedented rates, thanks to global warming, says Rose.

"By the end of our lifetimes the Arctic will be unrecognizable," he says.

There will no longer be any ice in the summer and there will likely be profound changes in populations of polar bears, fish, and other wildlife. The area will be open to vessel traffic, from cruise ships to fishermen to those looking for oil, gas, or seabed minerals.

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"Those things could prove disastrous to marine resources," Rose says. "But in protecting the unique environment of Franz Josef Land, those things can't happen there now."

The Pristine Seas expedition was completed by National Geographic in partnership with the Russian national park and the Russian Geographical Society. In addition to conducting scientific research, the team brought back photos and video and released a documentary film showcasing the unique environment of the islands. The team even had a close encounter with a polar bear.

"As this week shows, we really can protect large parts of our planet," Rose adds.

