An entire elk herd died Sunday night in a tragic accident after falling through Colorado's frigid Echo Canyon Reservoir, their frozen bodies found Monday morning.

In all, 21 elk drowned after the thin ice broke under their weight, just 50 feet from the shore of the lake, which lies just five miles south of Pagosa Springs.

"It's kind of surprising none of them got out," Joe Lewandowski, a Colorado Parks and Wildlife spokesman, told The Durango Herald. "That's what happens when you get several thousand pounds on the ice."

Elk can weigh upwards of 1,000 pounds, and travel in large herds during the winter searching through the snow for grass and shrubs to feed on, according to National Geographic. While this type of incident is rare, it's not unusual that ice can't handle the girth of hefty animals such as elk. A similar episode occurred in 2008 when 19 elk drowned at Paonia Reservoir.

In 2011, wildlife officers and local law-enforcement officials removed three cow elk that had fallen through ice at a private pond near Pagosa Springs, with one elk perishing in that incident.

"It doesn't happen all the time or very often, but it is a natural occurrence," Matt Robbins, a spokesman for with Colorado Parks & Wildlife, told The Denver Post.

A local Pagosa Springs resident captured a picture of the elk, frozen and dead, after they were retrieved from the reservoir. After being posted to Instagram, it was published on pagosasprings.com where it received over 100,000 views in less than 24 hours.

Wildlife officials have since removed the carcasses from the waters of the 118-acre reservoir, before the water froze over them and made it impossible to retrieve the animals.

Elk were once found across all of North America, but now they are primarily found in the West, especially in mountainous landscapes such as Wyoming's National Elk Refuge and Yellowstone National Park.

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