Poisonous rough-skinned newt 5

In 2012 I was on a hiking trip in Oregon and, tempted by the windfall of protein it would represent, I started to collect and prepare a bag full of rough-skinned newts for dinner.

Taricha Granulosa, the rough-skinned newt, is a very common species of salamander along the West Coast of the United states and British Columbia, from as far south as Santa Cruz, California to as far north as Alaska.  It is one of the most ridiculously poisonous animals in existence.

Rough-skinned newt

Taricha Granulosa in the Willamette Valley

I encountered this species often during 2012, when I walked the Pacific Coastal Range mountains.  They are as common as slugs or snails in these moist forests.

Since I had experience and gear for longer trips, I was fond of supplying myself with as much food as I could carry and heading out into the logging roads and into the national forests of Southwest Oregon.  I would find a nice piece of river, practice plant and animal identification, bushcraft, and forage on plants that I felt safe eating.  In 2012, I was a relative newcomer to bushcraft, but I had a good deal of hiking and camping experience.

One day, I was down by the river fishing for trout.  I was hungry.  Carrying all your own food means your trip is limited by how much food you carry, and more weight to haul around means slower travel.  I had been out for two weeks and was ready to hike back to town, but right then I had a craving for protein.

The fish were either missing entirely or just not feeding, because I fished a piece of river for two hours using every type of jig and bait I could think of.  After two hours I gave up the idea and started to get ready to turn in for the night.  As evening approached, I started hearing frogs chirping all around my camp.  There were a great many pools of water in a small forested flood plain, so I decided to go frog gigging.

When I found the frogs, I was greatly disappointed.  They were miniscule.  However, I noticed a massive amount of rough-skinned newt inhabiting the puddles and ponds of that area.  Well, protein is protein, said I, and got to work collecting a bag full of more than two dozen live, squirming, angry rough-skinned newts.

I opened up my gear and set up my camp stove, pot, and heated up some olive oil.  “Garlic would be nice,” I thought, looking at the dark slimy mass of creatures I planned to feast on.  I removed one of the largest newts and got out my knife, ready to dress them for dinner.  “There are so many of these animals here,” I thought, “If these are good, then I should have quite a windfall of protein that I don’t have to carry in.”

“Why are there so damn many?”

It was at this moment, with a Taricha granulosa held down and my knife poised to kill and gut the little amphibian, that my time observing the forest saved my life.  Why don’t I see the coyote, racoons, opossum, bear, or birds eating the rough-skinned newt?  Why are there so many here and nothing is eating them?  I’ve never heard of any North American animals being particularly toxic, but this particular critter has some kind of advantage here.

I let the rough-skinned newts go, and ate oatmeal that night, vowing to head into town to resupply and do some research when I got there.

What I learned next, I could hardly believe.  The taricha granulosa, or rough-skinned newt, is one of the most ridiculously poisonous creatures alive.  The skin glands of the newt produce tetrodotoxin, or TTX, a neurotoxin found in pufferfish, porcupinefish, ocean sunfish or mola, triggerfish, blue-ring octopus, and rough-skinned newt.  In the 1950’s, three Oregon hunters were found dead around the camp fire, with no signs of explanation.  A boiled rough-skinned newt was found in their coffee pot.  In 1979, an Oregon man in a bar swallowed a rough-skinned newt on a dare.  He was dead before the day was out.

Where the rough-skinned newt and the common garter snake share space, there is a war at work.  The toxin of the newt has increased in response to the resistance of the snake.  The 1950’s incident led to research by E D Brodie Jr., now of the Department of Biology, Utah State University.  This research was published in a 1968 paper on the toxin of rough-skinned newt.

“Thirty species of potential predators on Taricha granulosa were tested by injection or force-feeding to determine their susceptibility to adult T. granulosa skin toxin.  All species tested were found to be susceptible to Taricha skin toxin.  The action of adult T. granulosa skin toxin is identical to that described for tetrodotoxin from the eggs of T. torosa and the puffer fish.  Mammals and birds are susceptible to similar relative amounts of toxin; 0.0002 cc of back skin of T. granulosa killed white mice in 10 minutes.  Snakes other than garter snakes were about 200 times more resistant, and garter snakes were 2000 times more resistant than white mice.  T. granulosa was self-susceptible to large doses.  Garter snakes, Thamnophis sirtalis concinnus, were able to eat adult newts, even though they were killed by injections.  Taricha toxin was very stable and did not lose potency over an 11-month period.”

Thamnophis sirtalis

common garter snake, Oregon

I went back out into the forest, now properly terrified of hunting or gathering anything to add to my adventures.  Rainbow trout are surely safe to eat, thought I, since everyone is catching and eating them to the point they are fished out and restocked en masse by the fish & game service.  Out of curiosity, I look at what the trout are feeding on, and what was inside the belly of many catches gave me a chill.  Below is a photo of a rainbow trout that was caught, fully vigorous and living, with a rough-skinned newt in its belly.

Rainbow trout eating rough-skinned newt

Rainbow Trout have been observed feeding on the rough-skinned newt.

My concern grew from my newly acquired knowledge of the tetrodotoxin in the rough-skinned newt’s skin.  Here it has been digested by the rainbow trout, should I eat the fish?  I did eat the fish and suffered no effects from the experience.  I reasoned that several trout I caught that day are eating rough skinned newt, and this species of fish is so widely consumed by anglers that they need to be restocked annually by fish & game.  I was damn hungry and I ate the fish and felt fine.

Again, back to town to resupply and do more research, now totally confused.  I found very little in explanation when searching online, except I learned that some people are actually using rough-skinned newt as trout bait!  Here is a critter common to the Pacific Northwest that can be used like the poison dart frog of the Amazon, and we’re eating what eats it!

Does this mean the rough-skinned newt that these rainbow trout eat are less toxic?  Does it depend on the locality?  Is the rainbow trout resistant to tetrodotoxin, and does it bioaccumulate in the fish so widely stocked, caught, and eaten here in North America?

5 thoughts on “Poisonous rough-skinned newt

  1. Reply Sara Oct 14,2014 10:24

    So I found one of these before knowing what it was, played with it a little, he was dry, slow and sweet, then put it down and washed my hands. Not super duper good, but soap and water, then ate a burrito. Googled it, then threw the burrito out scared I had poison on my hands. This was an hour ago. With such little interaction, what is the possibility I am poisoned? I’m not kidding here. Psychosematically, I’m over analyzing everything I feel right now. I’m a mental health counselor to boot so I’m just trying to stay sober about the experience.


  2. Reply Amber Feb 10,2015 22:30

    Really interesting story! I will brinkg it up in my next green club meeting. We always go hiking and it would be cool finding one. I wonder why the fish that you ate wasn’t contaminated.

    Good luck with the next avventure!

  3. Reply Barbara Caudillo Mar 30,2015 16:37

    My grand-daughter went to outdoor school for a week in Oregon and during this time she handled about 100 of these newt’s, not knowing that they were poisonous and could also carry Trematode parasites. She arrived home out of sorts, crying for hours and the next day was running a fever that lasted several days. Had what looked like a bite mark on her hand. She has not been the same since. She has experienced major stomach pain, headaches and has lost her sunny disposition, at times feeling very depressed. She missed an entire year of school, and now suffers from panic attacks that have to be controlled with medication in order for her to attend school. She has been tested for parasites (basic test) which came back negative, and the doctor’s don’t know what is wrong with her. I’d advise never touching these newt’s and school camps shouldn’t allow children to handle them. Her teacher did tell her to wash her hands, but handling the rough skinned newts was just too big of a chance to take, and has majorly affected her life in a negative way.

  4. Reply Lynn B May 5,2015 21:06

    We found this cute little guy in Anacortes, thought it was dying, and were bringing it home to warm it up. So dumb! Googled it to find out what it eats – ahh! My husband handled it but half hour later has no effects. Should have thought – why is nothing eating this cute, slow-moving little guy with a bright ORANGE belly!?

  5. Reply Becky Williams Jul 29,2015 09:47

    Hey folks,
    I am a researcher who studies these newts and the resistant garter snakes. I got a degree working with Brodie, Jr., partly studying what happens to the snakes after they eat a newt. I wanted to clear up some misconceptions, so people are not afraid of or malign the newts. They have their place in the ecosystem and it is relatively safe to go out and explore nature.

    TTX is water soluble. That means that it does not easily cross the skin barrier. If you have a large cut or abrasion on your hand, I would not advise handling newts, but otherwise it is perfectly safe to touch them. Just wash your hands afterward. Your burrito was perfectly safe, Sara! As for your Granddaughter, Barbara, TTX does not cause the symptoms you describe. They sound more like a tick-bite and possible Lyme’s disease to me (of course, I am no expert in that realm, so it would be wise to visit another medical doctor). A large exposure to TTX would cause a tingling sensation; progressive symptoms would be paralysis and cessation of breathing because the diaphragm stops working. In a serious poisoning case, these symptoms express in a few minutes to an hour. However, with immediate supportive care (rescue breathing) and IV fluids, poisoning victims may fully recover in a few days. TTX is naturally flushed out through the urine so direct effects of TTX do not last more than a few days.

    I believe Brodie, himself, witnessed a newt crawl out of the mouth of a trout, which had been paralyzed by the TTX. The newt survived. I thought it was in his 1968 paper (mentioned in the article), but I would have to look it up to be sure. I am also not sure if the author identified the salamander in the stomach of the trout correctly; something in the gestalt of the head made me think Dicamptodon first, but after looking at some pics, maybe it was Taricha. Either way, I never found any evidence of TTX persisting in muscle of even resistant garter snakes after they eat newts. After 24 hours, there was no trace of TTX in anything but the kidney and livers of the snakes. The trout meat (muscle) should be safe. I would recommend against trout pâté just in case!

    It’s possible that if the trout were eating Taricha the individuals that are eaten are of low toxin levels. There is considerable variability in TTX levels within populations of newts, and populations can vary by orders of magnitude over relatively short distances (from watershed to watershed). Any attempts to eat highly toxic individuals by trout *should* be unsuccessful. Interestingly, one study found that two fish (a trout? and arctic char) could “taste” TTX because exposure to the molecule caused gustatory receptors to propagate a nerve signal. For most organisms, TTX is inferred to be tasteless. In any event, even resistant garter snakes were affected within 1 minute of trying to ingest a newt (which could take upwards of 30 min), thereby giving the predator a chance to assess the toxicity of the prey item and reject it if need be. So, particularly toxic newts in the population might be spit out by trout predators and those with little to no TTX might be eaten.

    It would be interesting to see if trout regularly eat Tarich in this or other populations, and if so, what the toxin levels of those particular newts are. Thanks for the interesting read!

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