A person had a close call after trying to hand-feed an elk at Grand Canyon National Park earlier this year. In a video recorded by another park visitor, the individual can be seen approaching the animal by a road and holding a branch out to it. Luckily for the person, the elk is distracted by a car engine and leaves, but not everyone who tries to offer elk a snack is so fortunate. Last year, a boy had his fingers bitten in Rocky Mountain National Park after trying to hand-feed an elk grazing by a trail.
The video was shared via Instagram account TouronsOfNationalParks, which highlights thoughtless antics at sites of natural beauty around the world. Other recent incidents have included a visitor shucking their shoes to walk barefoot on Grand Prismatic at Yellowstone, and another chasing after a wolf.
Feeding wildlife, even if done with good intentions, can have serious consequences, and can even result in the animal's death. It might be tempting to throw some of your lunch to the animals, but some human foods (such as chocolate and onions) are toxic to many animals, and could make them very unwell. Feeding animals can also result in them avoiding their natural diet in favor of human food, which can lead to nutrition deficiencies, and malnutrition if the supply of snacks stops.
Habituation is another problem. This is when a wild creature loses its natural wariness around people, and is more likely to put itself in a potentially dangerous situation. This might mean approaching cars, or coming into conflict with people. It's a particularly serious problem with bears, which have an especially keen sense of smell and quickly learn to target trash cans, cars, and campsites if they have found food there before.
Wildlife officers may eventually decide that a habituated animal needs to be relocated or euthanized for public safety.
The National Park Service (NPS) advises anyone paying a visit to the Grand Canyon to stay at least 100ft (30 meters) from animals like elk and bighorn sheep.
"Feeding animals is prohibited," warns the NPS. "This is for their safety as well as yours. "Wildlife will quickly become persistent pests to you when fed. Make sure to dispose of your trash properly, even the scent left over in an empty cooler can attract a wild animal."
If you're planning a trip to a US National Park in the coming weeks, our guide how to enjoy elk rutting season safely will help you make the most of this time of year.
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