National Parks Are Wild — Treat Them That Way
Every year, visitors are injured or killed in national parks by hazards that are entirely preventable. The top causes of death in parks are motor vehicle accidents, drowning, and falls. The top causes of injury are wildlife encounters, dehydration, and weather exposure. Here's how to avoid all of them.
Wildlife Safety
Bears (Grizzly and Black)
Grizzly bears are found in Yellowstone, Glacier, Grand Teton, and North Cascades. Black bears are found in most forested parks.
Prevention:
- Carry bear spray on every trail in bear country. It's more effective than firearms at stopping a charging bear.
- Make noise while hiking — talk, clap, or ring bear bells on trails with limited visibility
- Hike in groups of 3+ — bear attacks on groups are extremely rare
- Store food properly — use bear canisters in backcountry, bear boxes at campsites
- Black bear: Stand tall, make yourself look big, yell, throw rocks. If it approaches, fight back aggressively.
- Grizzly bear: Do NOT run. Back away slowly. If it charges, deploy bear spray at 30 feet. If it makes contact, play dead face-down with hands behind your neck. Fight back only if the attack is prolonged (predatory).
Bison and Moose
Bison: Stay 25 yards away minimum. A bison can sprint 35 mph and weigh 2,000 pounds. If it flicks its tail, paws the ground, or snorts, it's about to charge. Yellowstone bison injure more visitors than any other animal — they look docile but are not.
Moose: The most dangerous animal in North America by incidents per encounter. Stay 25+ yards away. A moose that lays its ears back, licks its lips, or lowers its head is about to charge. If charged, run — unlike bears, moose usually don't pursue far.
Snakes
Rattlesnakes are found in most western parks. Mojave rattlesbakes (Death Valley, Joshua Tree) are the most dangerous. Copperheads and cottonmouths are found in eastern parks.
If bitten: Stay calm, remove constricting items (rings, watches), keep the bite below heart level, and get to a hospital. Do not cut, suck, or tourniquet the bite. Antivenom is the only effective treatment.
Weather Hazards
Lightning
The #1 weather killer in national parks. Rocky Mountain, Grand Teton, and Yellowstone have some of the highest lightning densities in the US.
If caught above treeline:
- Descend immediately at the first sign of thunder (you can hear thunder from a storm within 10 miles)
- Avoid isolated trees, peaks, and ridgelines
- If you can't descend, crouch on the balls of your feet with your heels touching — minimize ground contact
- The 30-30 rule: if the time between flash and thunder is 30 seconds or less, seek shelter; wait 30 minutes after the last thunder before resuming
Flash Floods
Slot canyons and dry washes are flash flood zones. A thunderstorm 20 miles upstream can send a wall of water through a canyon with no local rain. Check weather before entering any canyon in Zion, Death Valley, or Canyonlands.
Heat
Death Valley, Joshua Tree, and Grand Canyon all record temperatures above 120°F. Heat stroke can kill in hours.
Heat safety rules:
- Drink 1 liter of water per hour of hiking in hot conditions
- Start before dawn and finish by noon in desert parks
- Wear a wide-brim sun hat and light-colored, loose clothing
- Know the symptoms of heat stroke: confusion, hot/dry skin, loss of consciousness
- Rest in shade at the first sign of dizziness, headache, or nausea
Cold and Hypothermia
Mountain parks can drop below freezing any month of the year. In Glacier and Yellowstone, hikers have died of hypothermia in July.
Cold safety rules:
- Carry a warm layer on every hike, even in summer
- Cotton kills — wear synthetic or wool base layers
- Wind chill at 10,000 feet can make 50°F feel like 30°F
- If you start shivering and can't stop, you're in early hypothermia — get out of the wind, add layers, and eat high-calorie food
Altitude Sickness
Symptoms appear above 8,000 feet and are more likely above 10,000 feet. Trail Ridge Road in Rocky Mountain reaches 12,183 feet. Glacier's Logan Pass is 6,646 feet. Yellowstone's Mt. Washburn is 10,243 feet.
Prevention:
- Ascend gradually (don't fly from sea level to 10,000 feet and start hiking)
- Drink 3-4 liters of water per day
- Avoid alcohol for the first 24 hours at altitude
- Consider acetazolamide (Diamox) if you've had altitude sickness before — consult a doctor
Water Safety
- Never wade in swift water above your knees without checking depth and current
- The Narrows in Zion — check flow rate. Closes at 150 cfs. Rent canyoneering boots and a walking stick.
- Great Smoky Mountains streams — slippery rocks, flash floods. Don't cross above knee-deep.
- Coastal parks — check tide tables. Getting caught by an incoming tide is a rescue or a fatality.
Emergency Preparedness
- Satellite communicator — essential for backcountry parks with zero cell service
- Tell someone your plan — trail name, expected return time, and what to do if you're overdue
- First aid kit — blister care, pain relievers, antihistamines, bandages, antiseptic
- Extra food and water — always carry 50% more than you think you need
- Headlamp — even for day hikes. Trails take longer than expected
Stay safe out there. Our complete national park rankings can help you choose the right park for your experience level.
Creating a Trip Safety Plan
Before every national park trip, create and share this plan:
Sent to: A trusted contact who is NOT on the trip
Include:
- Park name, trail names, and route direction
- Expected start and end time for each hike
- Vehicle make, model, color, and license plate
- Check-in times (e.g., "text me by 6pm each day")
- What to do if you miss a check-in ("Call the park dispatch at XXX-XXX-XXXX")
- 1 hour late: No action (hiking is slower than expected)
- 2 hours late: Contact attempts via text/call
- 4 hours overdue: Call park dispatch with the safety plan details
- Overnight overdue: Contact sheriff's office and initiate SAR
- NPS dispatch (varies by park — save the specific park number)
- 911 (works in developed park areas)
- Your satellite communicator SOS (if carrying one)
- Roadside assistance (AAA or equivalent)