Yosemite Dangers – Swift Current, Poison Oak, Bears & Snakes


Although the vast majority of park tourists will have a trouble-free visit, some things could go wrong. This gallery is dedicated to a few Yosemite dangers to mindful of during your stay.


1. Swift Current In Spring


Dangerous Merced River Rapids, Swollen in Spring
Merced River Rapids

More than any other concern, park goers should watch out for dangerous river currents. When the creeks and waterways swell with snowmelt in the spring, they become deceptively treacherous. Many hikers have slipped and fallen into the (seemingly) calm pools above waterfalls.

Although they might try to laugh it off at the time, they quickly realize that in fact, the water current is more powerful than it seems. If they are not strong swimmers, there’s no way they can escape the current – and their ultimate death, once they plummet over the falls. Remember, the rocks near the water’s edge can be slippery.


2. Poison Oak


Poison Oak Leaves, with new spring / early summer red growth
Poison Oak Leaves

Another (albeit less dangerous) threat comes from poison oak. This toxic plant can produce an itchy, puss-filled rash wherever it comes in contact with your skin. However, some people are fortunate to be immune to it. I am not one of them. Check the link below for more info about this roadside nuisance.


3. Bears – Yosemite Dangers


Mama Bear & Cub by Merced River Boulders - Yosemite dangers
Mama Bear & Cub

Although people generally tend to be afraid of these large park animals, they have yet to kill a single person in all of Yosemite’s history. If an attack did happen for some (super unlikely) reason, it would likely be because a visitor came between a mama bear and her cubs.

Best to keep a good distance between yourself and any bears you might encounter. Make sure you never accidentally trap or block a bear on the trail – you should be fine.


4. Rattlesnakes


Rattlesnake Striking and rattling tail - Yosemite dangers
Don’t get too close

Though the snake above was photographed just outside the park, keep in mind that you may encounter rattlesnakes on warm days in the park. If you do, don’t panic. They will not pursue you or anything.

Again, as long as you do not step on or make one feel trapped and threatened, you really have nothing to worry about. If you do happen to be bitten, seek a park official immediately. Bites are usually serious, but not fatal.


5. Rock Slides & Avalanches – Yosemite Dangers


Finally, watch out for rock slides while driving in the park, especially in the high country on Tioga Road. I remember one day hearing a loud cracking sound that I mistook for lightning at first. I was photographing Pohono Bridge on the valley floor, and I looked up to see where the noise was coming from.

Though it couldn’t quite reach me, it was a rock slide coming down the granite mountain overhead. Thankfully it did not dislodge some of the larger boulders sitting in wait on the high mountainside.

As for avalanches, I really just mean for those adventurous hikers who venture onto the snow covered trails. I did this on the Mist Trail once in early spring. There was a thick blanket of snow on the ground still, and again I heard some loud cracking noises in the distance.

A companion told me that it was in fact melting snow falling down from the cliffs above.

Just so you know, I have never been bothered by a bear, fallen in the river, or had a direct hit with rock slides or avalanches. Again, these occurrences are rare, but it never hurts to be cautious.

For more related photos, check out my bears photo gallery, and my article how to avoid poison oak in Yosemite.

Looking for lodging? Check out my Yosemite Hotels page.

Show the Sierra some love – Share this page:

About My Photos

The images on this website are available for licensing and/or sale as framed prints. If you’d like to purchase them for a blog, news article, or gift, feel free to contact me with the specifics. This way you’re supporting photographers such as me directly (as opposed to buying from a faceless stock photo corporation).

Pinterest users: By all means, feel free to pin!

– Nathan Allen

About Me

Photographer Nathan Allen

I’m Nathan Allen, photographer / creator of YosemiteParkPhotos.com (Yosemite Photos) and international travel site I Dreamed Of This. In truth, I lived in San Francisco, New York, & Singapore…but nothing compares to life in the mountains. I share my experiences HERE.