Staying Safe at Yosemite National Park

Photo of a Bear Trap
Bear trap. Follow park rules regarding food in cars as bears will break into vehicles if they smell something interesting inside.

For any emergency in Yosemite National Park, dial 911 from most phones (hotel and retail phones may require 9+911). Yosemite NPS runs its own dedicated emergency dispatch. If you dial from a cell phone, first mention that you are in Yosemite as many cell phones route to a call center in your number’s area code.

Though increasingly harder to find, there are payphones scattered throughout Yosemite similar to the phone pictured above at Glacier Point.


  • 4 Yosemite Medical Clinic, 9000 Ahwahnee Dr (Yosemite Valley), ☏ +1 209 372-4637. Drop-in and urgent care May-Sep: daily 9AM-7PM; Oct-Apr: M-F 9AM-5PM. Routine and emergency medical care, 24-hour paramedic/ambulance services, lab, and Mountain Crisis Services for victims of domestic violence. (updated Apr 2015 | )


Over the years the park’s bears have become accustomed to scavenging trash and food left out by humans, and will even break into cars and tents to get it. While not the larger grizzly bears that once roamed California, black bears are strong enough to tear a door off of a car with ease. Luckily they usually prefer to avoid humans, so they’ll most likely do their work on vehicles left at trailheads or in parking lots. Prevention is remarkably simple: never leave food or scented items (deodorant, air fresheners) in your car or bring them into your tent. Heed this advice! Leaving even just a tube of toothpaste or empty food wrappers in a car may result in thousands of dollars of damage to your vehicle should a bear choose to investigate the smell! Bear-resistant storage units are provided at park campgrounds and overnight parking areas: use them.

To avoid bear encounters while hiking, make noise so that the animal knows you are coming. This approach will also help to avoid encounters with mountain lions, which also inhabit the park. Other animals, such as the herds of deer which can be found in the park’s meadows, can be equally dangerous; a young boy was killed by a deer in Yosemite Valley several years ago. Give all animals their space, and never feed any park wildlife.


Yosemite Valley Lodge (and possibly other accommodation areas) has no outside lighting. This is to reduce light pollution and allow the stars to shine down. If moving about the area at night (even to go to the reception office or restaurant) ensure that you have a flashlight (torch), as walking in the dark can be quite hazardous. In general, avoid long hikes after dark.


Other natural dangers in the park come from the weather. Hypothermia can be a concern at higher elevations where temperatures can drop below freezing throughout the year. Dress in layers, and be prepared for storms and rapid changes in temperature. When storms are approaching avoid open areas such as the summits of the park’s many granite domes; lightning strikes these areas regularly. If a storm does approach, get off of high, open ground. When hiking wear sturdy footwear and drink plenty of water – if you are thirsty that is an early sign of dehydration. Be aware that the sun can be intense at higher elevations and when reflected off of snow, so sunscreen is important. In the winter, take the weather term “Winter Storm Warning” very seriously as it means a significant storm is definitely coming.

Being prepared

Every year, visitors to Yosemite will require medical care because they didn’t have the supplies and information they needed. While the park has amenities to aid tourists, Yosemite is huge and you can easily find yourself miles away from potable water and information you need. Always do your homework before any hike. Figure these things out:

  • Understand not just the length of your excursion, but also the elevation gain (how steep will it be?), the exposure (will there be shade?), and the availability of potable water (where can I fill my water bottle safely?).
  • Bring water and food with you––never rely solely on park amenities, which are sparse and sometimes hours away from you. At the high season, you might wait 30 minutes or more for gas or food. The same hike can require different amounts of water depending on the time of day, so a hike that might require a liter of water at 8AM might need 3 L and a long rest if you start at 4PM. Few trailheads, especially outside of the valley, will have running water.
  • If you camp in the backcountry, do your homework; you can seriously endanger yourself without proper knowledge.
  • Always set a turn-around time (if you’re not at the top of a hike by a certain time, you will turn around to get back to your transportation by sunset) and tell someone where you are going/what time to expect you back. It’s easy to forget that there’s not much of a paper trail for where you are hiking, which means you are harder to find if you are in distress.

On the trails

Hikers should follow all posted signs – if a trail is closed due to ice, landslide, or some other reason do not ignore the closure as doing so endangers both the hiker and any area that must be traversed to go around the closure. On the Half Dome trail, hikers should always remain inside the cables for their ascent and descent. Hikers died on this section of trail in Summer 2009.

The park’s waterfalls pose another potential hazard. Do not attempt to get close to the waterfalls, especially in the spring. This includes swimming above the waterfalls at a distance of less than 1 mile (about 1.6 km) The force of the water will easily sweep a person off their feet and over the falls. Being swept over any of Yosemite’s waterfalls is invariably fatal.

Other concerns

The greatest danger in the park comes from the thousands of park visitors. Petty thieves and traffic accidents are two issues to be aware of. Follow park speed limits, lock your vehicle, and be aware of your belongings, especially in Yosemite Valley. Violent crime is extremely rare in Yosemite, but given the numbers of people that visit you should expect that a few unsavory characters will be visiting too.

The National Park Service provides the primary law enforcement and fire protection in the park. NPS is supplemented by Aramark Security, who handle a number of calls for service on Aramark land assignments. Aramark Fire is paged out along with NPS Fire, and handles a large number of calls in Yosemite Valley.

Lost and found

There are two major Lost and Found operations in Yosemite. One is run by the National Park Service. It can be reached at ☏ +1 209-379-1001. The other is run by Aramark, and can be reached at ☏ +1 209-372-4357. They coordinate as best as possible, considering they are a half-hour away from each other. They process thousands of items each year and surprisingly get a number of items back to the rightful owner. Because of the thousands of items lost or found, generally, you will not get a return call unless your item has been found and turned in correctly.

Items that are found that cannot be returned to the owner are generally turned over to recognized charities. So, if you don’t get your item back, and if it is turned in by the finder, at least you can rest easy that it will eventually go to a good cause.