A bitter-cold lake. A canoe, paddles and life vests. A vacant campsite. And at least one person deceased.

Authorities continue to investigate the site in Yellowstone National Park where the body of a National Park Service retiree was found on Monday. And the search continues for his missing half-brother, also a retired Park Service employee and former Navy SEAL.These two men do not sound like inexperienced, unprepared outdoor recreation enthusiasts.

Associated Press reports the body of 67-year-old Mark O'Neill was found Monday along the east shore of Shoshone Lake in Yellowstone. A brief fact-check on the lake reveals that its average temperature is lower than 50 degrees, and survival time in such cold water is brief. Shoshone Lake is the park’s second-largest lake, and is located at the head of the Lewis River.

But, was drowning or hypothermia indeed the cause of Mr. O'Neill's death? As we post this, still reported missing is his half-brother, 74-year-old Kim Crumbo. The two men were reported missing by family members Sunday, September 19, when they were overdue for their return from a four-day backcountry camping trip to Shoshone Lake.

A Yellowstone National Park crew found found the vacant campsite with a large amount of gear. Search and rescue crews continued ground, air and water searches Tuesday. Park officials have limited details released, but did assure people that they will provide updates when appropriate to do so.

They have also asked the public to maintain distance from any law enforcement personnel and their equipment. Even in a remote area, you know how human nature and curiosity can get the better of us.

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