Tourists Should Avoid This Simple, Harmful Mistake When Visiting National Parks

Think of some of the places people can go to get connected to nature and revel in its beauty: chances are national parks will be one of the first that come to mind. The fresh air in the parks, and the presence of diverse wildlife, lakes, forests, and mountains make them great places to unwind.

But what many tourists don't know — or probably just don't consider enough — is that these things, these ecosystems that make these parks beautiful, are actually fragile and need protection. Some human actions that you might consider harmless are oftentimes greatly dangerous to the plants, animals, and even the soils and water systems. And damage to some of these natural phenomena may take decades of recovery, as the harm ripples through the environment.

Among the different mistakes tourists make when visiting national parks, leaving food or trash behind is arguably the most common. People drop wrappers, fruit peels, food scraps, and whatnot, thinking it's nothing. After all, why would a single candy wrapper upset a river or harm animals and plants? However, the common saying, a drop of water makes a river, would make sense here: Overtime, those seemingly insignificant bits of food and trash add up, subsequently altering the behavior of animals in the park, sometimes introducing invasive species, and ruining soil and water quality.

There's a reason many parks use a principle known as "Leave No Trace." They're simply protecting the parks' delicate ecosystems. Essentially, you're to leave the park as clean as you found it — drop nothing, feed no animal, and stay on marked trails. With reports suggesting that national parks across the U.S. generate more than 100 million pounds of waste yearly, it's no surprise why parks would want visitors to be mindful of their actions.

For starters, when wildlife feed on human food, it leads to something experts call "food conditioning," as the animals begin to associate humans with food. They gradually lose their instinctive fear of people, then tend to approach campsites, parking lots and trails more often, while growing bolder and more aggressive. This can be dangerous for both humans and animals, with risks of attacks to humans, and diseases for both. As a matter of fact, some animals become so threatening to the public that they have to be euthanized.

Pests, bugs, and rodents may also spike unnaturally, and potentially out-compete local species. A case in point was Carlsbad Caverns National Park, which got littered with Cheetos in 2024. The processed corn started causing mold and fungi buildup, thanks to spiders, crickets, and mites that had helped the spread. If park rangers hadn't noticed the problem early, the innocent bats that are natives of the cave could have faced the consequences. Moreover, pieces of trash, such as plastics, degrade the environment. Toxic chemicals from some of these wastes can leach into soil and waterways, and even impede plant growth.

The best way to enjoy your park visit without harming it, or feeling guilty later, is to stay mindful of things you should or shouldn't do. First, keep in mind that whatever you pack in must be packed out. As a practical solution, you should always bring trash bags in with you. Whatever food you bring with you, take the litter or leftovers back home for proper disposal, or use park bins if available. Importantly, don't assume that a national park will provide bins or have staff to clean up after you. Consider it your responsibility as a visitor.

Remember always that you're not to feed the animals, no matter the circumstances. Therefore, how you store your food and other items (like soaps, deodorants, and sunscreens) also matters in order to avoid enticing the animals through scents or other means. In places with bears or other large animals especially, it's essential to keep strong-smelling items in wildlife-proof containers. Specifically, you can make use of food lockers or bear canisters. It may also be sufficient to lock some of these items in the trunk of your car. As the National Park Service puts it, anything that goes in your mouth or on your skin requires conscious storing.

All in all, being proactive might just be all you need to avoid this mistake altogether. Plan your meals such that you don't end up with leftovers. Likewise, go for snacks or meals that tend to be less messy or smelly, and opt for reusable containers as much as possible. Also, make sure to inspect your campsite thoroughly when you're done eating and before leaving the park completely, so you won't forget anything behind.