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Alpine Toads and the Chytrids that Love Them

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


When you read a story, you may occasionally wonder what the reporter went through to get it. About a month ago I arose at 5 a.m. to accompany two wildlife biologists and three fisheries volunteers into the high country of Colorado in order to report a story that came out in High Country News this past week.

Over the course of a 12-hour day, we covered about 10 miles, climbed several thousand feet, slogged through bogs in which I sank to my calves, swatted clouds of mosquitoes, and were drenched by rain in order to get to the high ponds and puddles where boreal toads breed. I do it all for you, dear readers.

But in truth, it was gorgeous, I loved every minute, and there's no where else I'd rather be in summer than the high country of Colorado. Here's what it looked like up there, just before it rained:


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You can see the thin outline of the silting-up beaver ponds where the toads breed in the middle distance.

It being me, I couldn't help but notice a few other interesting things on the way to and in the bogs, such as

this stalked bog cup fungus -- rare in Colorado, and

these slime molds, which had just crawled up a log and were getting ready to fruit (I actually saw lots of slime molds that day), and

these gorgeous purple fairy fingers, which where hiding in the shadows around a conifer, and of course,

one bull moose. It's amazing what you can see if you just look.

But here's an ubercute photo of the object of my travails, a boreal toad, they of cream-striped backs and glinting, coppery eyes:

10,500 feet is an impressive altitude for a human to live at. For a cold-blooded toad, it's downright extraordinary -- but that is just what the alpine boreal toad does. No other amphibians or reptiles in the West can survive at these altitudes (rattlesnakes, for instance, can't live above about 8,000 feet). Doreen Sumerlin, one of the Forest Service biologists who accompanied me on this trip, said that boreal toads could even cross high tundra passes of 12,ooo feet or more if the tundra is moist enough. Anyone who's ever tried crossing passes at that altitude knows just what a feat it can be even for a well-fed, warm-blooded human.

But even these extraordinary toads -- like amphibians worldwide -- are in trouble at the hands of an aquatic fungus called a chytrid (KIT-rid). This was the subject of my story. Later this week I'll put up a post here looking in detail at what chytrids are, where this particular chytrid -- with the tongue-twisting name Batrachochytrium dendrobatidis -- came from and how (we think) it does its nefarious thing.

As for my little adventure, I was lucky to get to see both toads and tadpoles for my trouble, and even survived tripping and falling arse over teakettle as I was bushwhacking through the willow thickets around the ponds, whereupon my reporter's notebook took an alpine dip and -- miraculously -- maintained legibility. Note to self: in future, use pencil when reporting from the great outdoors. Sadly, I didn't get an "after" shot of me covered in mud up to my knees because it was raining when we got back to the trailhead. Next time!

You can see my resulting short article about the toads and their plight in High Country News here, which is accompanied by a beautiful selection of photographs taken much more skillfully than mine by wildlife photographer David Herasimtschuk. Enjoy!