Man attacked by bear, films aftermath (WARNING: Graphic)

Monday, October 3, 2016, 5:57 PM - WARNING: Graphic content, reader discretion advised.

A Montana man's account of being attacked by a bear has gone viral, after he posted pictures and video of the aftermath on Facebook.

Todd Orr was walking in a valley in southwest Montana Tuesday when he happened upon a grizzly bear and her cubs. Though they at first ran from him, the bear quickly turned and bore down on him, despite Orr using a bear repellent spray and making noise to show he was human. 

Orr dropped to the floor and tried to protect his arms and neck. His Facebook page carries a lengthy and chilling account of what happened when the bear reached him.

"She was on top of me biting my arms, shoulders and backpack," Orr wrote Tuesday. "The force of each bite was like a sledge hammer with teeth. She would stop for a few seconds and then bite again. Over and over. After a couple minutes, but what seemed an eternity, she disappeared."

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He suffered puncture wounds to his arms and shoulder, but didn't stop to dress them, as he wanted to put some distance between him and the bear in case it returned.

But just minutes later, he heard a sound, turned around, and saw the bear, standing ten metres away. Again it charged, and again Orr dropped down and tried to protect his head and neck, but this time the attack was longer, and more brutal, as he explained:

One bite on my forearm went through to the bone and I heard a crunch. My hand instantly went numb and wrist and fingers were limp and unusable. The sudden pain made me flinch and gasp for breath. The sound triggered a frenzy of bites to my shoulder and upper back. I knew I couldn't move or make a sound again so I huddled motionless. Another couple bites to my head and a gash opened above my ear, nearly scalping me. The blood gushed over my face and into my eyes. I didn't move. I thought this was the end. She would eventually hit an artery in my neck and I would bleed out in the trail... But I knew that moving would trigger more bites so a laid motionless hoping it would end.

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Then, Orr says, the bear stopped, and stood on top of him in silence for 30 terrifying seconds while he waited for the attack to resume. Then, abruptly, she left.

Now more seriously injured, and with a "useless" left arm, he fled again, reaching his truck, 45 minutes away, and driving to the hospital. He called his girlfriend to let her know what happened as soon as he had cell service, followed by a call to 911 to ask them to let the hospital know he was on the way.

An x-ray showed his ulna in one arm was chipped, and he underwent eight hours of care, including stitching.

"Most were arm and shoulder punctures and tears. A 5" gash along the side of my head will leave a nasty scar, but I'm hoping my balding doesn't come on too quickly and leave that one exposed," Orr wrote, adding he also has numerous scrapes and bruises either from the bear's teeth and claws, or from being slammed repeatedly into the earth during the attacks.

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Though Orr survived and is recovering, his account suggests he did most things right to warn the bears he was coming, such as calling out periodically so he wouldn't surprise them.

CBC reports Montana Fish, Wildlife and Parks plans to close off the area where the attack occurred, and is investigating the incident. 

Spokesman Ron Aasheim told CBC this was the area's fifth bear attack this year so far. The number of grizzlies in the area has risen from about 200 in the 1970s to around 700 today, thanks to conservation efforts, likely increasing the chance of an encounter.

"It gets your attention when you start hearing about this and all of us now pack bear spray. It's a different world," Aasheim says.

The popular imagination sometimes puts bear risk at its highest in the spring. However, the B.C. Conservation Officer Service says, in B.C. at least, that though there is a spike in calls in the spring, the most calls come in the late summer and early fall, highest in August, September and October.

Calls for grizzly bears are not as common in B.C. compared to black bears. Statistics show grizzly calls peaked in September at 97 last year. That month also saw the largest number of calls for black bears, with 5,408 sightings.

SOURCES: CBC News | B.C. Conservation Officer Service