Forming a circle around a fight between two bull moose fighting is never sensible - because they tend to charge off afterwards.
But that's exactly what one park ranger witnessed, according to a new Reddit thread in which rangers reveal "the stupidest things they've ever seen a tourist do in a national park".
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More than 500 tales of ridiculous and hilarious incidents - which include travellers stealing baby alligators, people going to the toilet in store cupboards and walkers taking selfies with bears - flooded the website when the post started on Monday.
One user, king_bestestes, said that his "favourite" tourist blunder story came when he was standing inside a national park's visitor centre and a family accidentally smothered themselves in bear spray - an ultra-hot pepper spray.
He said: "I was in a national park at the visitor's centre. Suddenly, there's this huge commotion and a lot of screaming from the lobby. I head over to find an entire tourist family crying and screaming and the park staff trying their best to manage the situation. Then the air shifts and it hits me.
"They had applied a liberal amount of bear spray all over themselves and the entire lobby. Apparently, they had mistaken the wording of 'bear repellent' and had assumed it was to be used like mosquito repellent.'
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Another user, ColorMeStunned, described a woman becoming angry because "the trees look the same as the ones at home". And user Choniepaster said that while working as a ranger he saw a group of boy scouts hacking down trees.
He said: "A group of boy scouts decided they wanted to try to build a raft and started sawing away at young trees. That is super illegal. I think after they were caught they got fined something like $3000 (£2,070) per tree, I can't remember exactly."
Commenter Tragic-Story said that at Shark Valley in the Everglades National Park tourists regularly try and steal baby alligators.
He said: "Every now and then some idiots will try to steal baby gators. This is utterly stupid, not only for the fact that they grow up to be full size gators, but because when the little gators feel threatened, they cry, which attracts all the adult mama gators in the area. Which ends up being a huge problem since it's literally in the middle of the Everglades and swarming with gators."
A large number of rangers highlighted that tourists often attempt to stroke and get close to the animals.
One user said "photographers are the worst" because they "do whatever they want".
He said: "I've seen a horde of cameramen paparazzi following a grizzly bear. All he needed to be was hungry and irritated and he could have easily killed a handful of them. They kept a distance but not good enough, especially for a grizzly. But photographers never listen to us."
Another user added: "A lady was upset because a ranger wouldn't let her go pet a bear cub. She brought lunch meat to entice it closer to her. Lady, your arm is lunch meat to a bear."
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Other incidents included a woman walking between two caribou despite rangers warning her not to, a man attempting to pet an irritated moose and a holidaymaker offering wild animals carrots in exchange for selfies.
User Littlekiwi17 said: "I'm a ranger in an urban area. We were having a big event at one of our parks. My partner and I needed to grab more trash bags so we made our way to the comfort station which has bathrooms and a utility closet. My partner is directly in front of me and as he pushes the door to the utility closet open he stops dead.
"I can see over his shoulder and there is a lady squatting over the floor and peeing everywhere. The lady yelled and my partner was so caught off guard that he apologised and closed the door. I had tears coming from my eyes because I was laughing so hard. There is no way this room could be mistaken for a bathroom, we keep leaf blowers, rakes and tools in there."
User burtmacklin00seven revealed that his father worked as ranger at a national park and witnessed an incident that saw several tourists hospitalised after they circled two wild animals that were fighting.
He said: "When I was a kid my dad worked at Grand Teton National Park. One morning two buses of tourists from China saw two bull moose fighting and decided to pour out and form a ring of people, three deep, all the way around the fight.
"Naturally when the fight ended the moose charged in opposite directions through the crowd and hospitalised several."
Another, Tw97095, concluded that he was shocked by the number of people "having sex in the park".
He said: "I worked as a seasonal park ranger in Maryland a couple years back. The number of people caught having sex in the park was kind of shocking to me. I worked in a park with miles of trails and over 100 acres of woods, yet the folks I caught having sex were in the most conspicuous places.
"As a park ranger, I don't care if you get busy in the woods, but why would you do it near public areas where you can be seen by families? Just walk well off the trail and do your thing."