The Terrifying Prospect Of Rats Chewing Your Rope. And What You Can Do About It.

It's an age-old problem, and a dangerous one. Here's three ways to minimize the risk.

Lock Icon

Become a member to unlock this story and receive other great perks.

Already have an Outside Account? Sign in

Outside+ Logo

All Access
15% off New Year Sale
$7.02 / month*

  • A $500 value with everything in the Print + Digital Plan plus 25+ benefits including:
  • Member-only content on all 17 publications in the Outside network like Rock and Ice, Outside, Backpacker, Trail Runner and more
  • Annual gear guides for climbing, camping, skiing, cycling, and more
  • Gaia GPS Premium with hundreds of maps and global trail recommendations, a $39.99 value
  • Today’s Plan training platform with customized training plans
  • Premium access to Outside TV and 1,000+ hours of exclusive shows
  • Annual subscription to Outside magazine
Join Outside+

Print + Digital
50% Off New Year Sale
$2.00 / month*

  • Annual subscription to Climbing magazine, and a coffee-table edition of Ascent.
  • Access to all member-exclusive content on
  • Ad-free access to
Join Climbing

*Outside memberships are billed annually. Print subscriptions available to U.S. residents only. You may cancel your membership at anytime, but no refunds will be issued for payments already made. Upon cancellation, you will have access to your membership through the end of your paid year. More Details

Question: I was rope-soloing at a crag near my home in Bozeman, Montana, and got to the midway anchor, where I had clove-hitched the rope so it wouldn’t rub on the edges above. Then I saw a big pack rat in the crack right by my rope. What should I do—go somewhere else? How likely is the rat to chew on my rope while I’m climbing?

—Emily Stifler Wolf

Gear Guru: Rats have been a problem since the dawn of humanity, and are blamed for helping spread the Black Death, a plague that killed some 25 million people in Western Europe. Out on the rock, rats and mice are known to pillage foodstuffs on ledges, gnaw on packs, and chew on ropes and slings, a point made clear to me 10 years ago.

That winter, so many snows ago, I led a local ice climb, an unnamed flow about 50 feet high, more of a warm-up than a real route. At the top, I clipped to a fixed sling tied around a large chockstone lodged in a chimney. Though faded, the sling otherwise appeared fine. I yelled, “Take!” to Ivo, my Czech friend who loves to sing at the crag while belaying. Just before I leaned back, however, I gave the sling a good yank—maybe I have Spidey Sense, but the sling broke, and small sticks and other nesting material rained down. A rodent had chewed through the webbing behind the chockstone, where I couldn’t inspect it. A groundfall from 50 feet (I hadn’t placed any pro) into snow probably wouldn’t have had the worst outcome, but it wasn’t high on my to-do list, either. 
Lesson: Check fixed slings before you commit, inspecting their entire length, and double up on slings when you have uncertainties.

You may be wondering why I haven’t suggested you pour d-Con in the crack.

My incident is related to yours, Emily, because it illustrates what you most fear: a fixed rope or sling chewed to the breaking point by a critter. You could climb somewhere else, sure, but maybe there’s a rat there too, so relocating is an imperfect solution if you continue to self-belay on a fixed line.

Ascending a fixed rope, whether jumaring Iron Hawk on El Cap or toprope self-belaying with a Micro Traxion, is risky. There’s the danger of pesky creatures making a nest out of your rope, but other hazards abound—the rope can saw over on an edge or be cut by rockfall. You can’t eliminate all risk with fixed lines—this is climbing!—but you can minimize it.

Minimize risk:

1. Visually inspect the rope from the ground. Whip the cord around so you can see all sides for its full length. If you can’t do this because part of the rope is out of sight or is too distant—a common scenario—then refer to points two and three.

2. Tie off the rope to intermediate points of protection, just as you said you did. Doing this reduces the amount of rope in play and lets you ensure it’s running well over any lips and bulges; it also keeps your weight from coming onto the rope where it runs over the edge of the crag—generally the biggest bend/angle in the rock—every time you fall. Just know that untying the rope when you arrive at a knot is usually problematic, requiring you to clip into and hang on gear. Resolve this by strategically placing the knots within reach of no-hands stances; you might also use “easy-undo” knots like the clove hitch.

3. Use rope protectors where the rope rubs over edges. This tactic is common for fixing on big walls. For free climbing, it has the same issue as point No. 2: You need to remove the rope protector to continue past it. It also doesn’t address rodents.

Be kind: You may also be wondering why I haven’t suggested you pour d-Con in the crack. Killing the rat would solve the problem, right? It might also cause collateral damage, poisoning other critters. Don’t do this, please. Just because creatures can’t speak (or they do, and we don’t understand) doesn’t mean they aren’t our friends, and even though we might fear them—or the plagues they carry—they deserve kindness and respect. Reflect on this proverb when temptation strikes: “Whoever is righteous has regard for the life of his beast, while the wicked are always cruel.” Gear Guru has spoken!