Arctic Adventure "Nightline" traveled to Baffin Island in the Canadian High Arctic to track narwhals, one of the most elusive creatures on the planet. Known as the unicorn of the ocean, they feature a single tusk that can grow up to 10 feet long. ABC News' Linsey Davis and producer Alex Waterfield endured inhospitable climate and dangerous, cracking sea ice on their journey with Arctic Kingdom Polar Expeditions. Glenn Williams/National Institute of Standards and Technology

Arctic Adventure The "Nightline" team traveled with Inuit guides on snowmobiles and Komatik sleds. As they journeyed to the Floe Edge, they rode over lakes of melted water atop sea ice floating in the ocean. Cracking sea ice has become a major issue here, not just because it creates hazards but because the animals and indigenous people rely on sea ice to survive. Eric Coomes

Arctic Adventure A trio of Narwhals race off in the distance beyond the Floe Edge. If sea ice continues to disappear in the Arctic, the narwhals, not polar bears, will be the first to become extinct. There are about 80,000 left. Dr. Peter Ewins of the World Wildlife Fund Canada said the rates of ice loss are "unprecedented." "The arctic is warming on average about twice as fast as the rest of the planet," he said Eric Coomes

Arctic Adventure The Inuit guides overlooking a large crack in the ice, trying to plan how the group and Komatik sleds can safely cross without slipping through to the ocean beneath. The cracks have grown enormously since the beginning of the trip, and the hunters and trappers organization has called the group back from the Floe Edge as the gaps are becoming increasingly unsafe. Eric Coomes

Arctic Adventure The picturesque Hamlet of Pond Inlet, Nunavut beneath the mountains of Sirmilik National Park. This remote village was the closest town to where the "Nightline" team was tracking narwhals. The group set up camp at a site about four hours away by snowmobile. Eric Coomes

Arctic Adventure This shows the "Parking Lot" outside of Pond Inlet where all the Inuits leave their snowmobiles and Komatiks on the ice. Eric Coomes

Arctic Adventure A silhouetted Inuit man canoeing across a deep crack in the ice with the mountains of Sirmilik National Park towering above. The Inuit people are indigenous to this Arctic region and their food comes whatever they can "harvest" off the land. One Inuit man named Jobi told ABC News' Linsey Davis that aside from occasional work serving as a tour guide, he doesn't have any other income. Eric Coomes

Arctic Adventure A ringed seal is a staple in the Inuit diet. This seal was hunted by the Inuit guides to provide food for their families. Living off the land is important to them because food prices are exorbitantly high here after being shipped in from the South. Eric Coomes

Arctic Adventure Pictured here is Jobi, an Inuit hunter, climbing up a cliff without safety restraints to harvest the eggs of Black Muirs so he can feed his family. Eric Coomes

Arctic Adventure An Inuit mother and daughter cooking fresh seal meat in the traditional manner. The prepared dinner of "country foods" including seal and Black Muir eggs was shared with friends and neighbors in the community. Eric Coomes