The iconic Devils Hole pupfish somehow keeps hanging in there

Transcript

DANIEL ESTRIN, HOST:

Have you ever felt stuck in a bad situation that you couldn't get out of through no fault of your own, and all you could do is just make the best of it? If so, maybe you can relate to this next story. It's about one of the world's rarest fishes. As part of our Weekly Dose of Wonder series, NPR's Nell Greenfieldboyce checked in with a tiny, shiny fish that somehow just keeps hanging in there.

NELL GREENFIELDBOYCE, BYLINE: In a section of Death Valley National Park, off a dirt road, there's some chain-link fence and razor wire. It surrounds Devil's Hole. Kevin Wilson went there in the 1970s as a kid.

KEVIN WILSON: So I just remember, as a young lad, just laying down on this wooden observation deck, looking down into this immense hole in the ground. And it was fascinating.

GREENFIELDBOYCE: Way down at the bottom of this cavern is a small pool of water - the only natural home of an endangered species.

WILSON: The Devil's Hole pupfish are only found in this one location, which is the smallest known habitat for a vertebrate species.

GREENFIELDBOYCE: Wilson is now with the National Park Service. He says male Devil's Hole pupfish are an iridescent blue. The females are kind of green.

WILSON: The biggest the Devil's Hole pupfish gets is about an inch - so about the size of your thumb.

GREENFIELDBOYCE: Thousands of years ago, these fish somehow got trapped in this inhospitable fishbowl made of rock. The water is hot...

WILSON: It's 93 degrees Fahrenheit all the time.

GREENFIELDBOYCE: ...And there's not a lot of oxygen.

WILSON: Here's this fish that lives in this extreme environment. How does it cope?

GREENFIELDBOYCE: Sometimes, it doesn't cope very well. A decade ago, there were just 35 fish - 35 - but its numbers are bouncing back. Last year, a count in the spring showed 175 fish. This spring's count showed the population is holding steady at 175. That may not sound like a lot, but Wilson says it's the best that the pupfish have been doing in about two decades.

WILSON: Well, the question that I receive and my colleagues receive is, you know, why? And so, you know, we're trying to answer that.

GREENFIELDBOYCE: Part of the answer could be some recent dramatic events. Jenny Gumm is with the U.S. Fish and Wildlife Service. She says, a couple years back, there was a flash flood. An enormous amount of water rushed into Devil's Hole. The churning water was so muddy, it looked like chocolate milk.

JENNY GUMM: And I really had to face they might be extinct.

GREENFIELDBOYCE: When it was safe, she went to the hole to check.

GUMM: There they were (laughter).

GREENFIELDBOYCE: It turns out the flood may have been beneficial by bringing in nutrients.

And then there's earthquakes. Big, far-off earthquakes have created mini tsunamis inside Devil's Hole. The sloshing water may have helpfully cleaned off a rocky shelf that the fish use to eat and spawn. Steve Beissinger is with the University of California, Berkeley. He says the Devil's Hole pupfish are famous in conservation circles.

STEVE BEISSINGER: It's certainly, in many ways, an inspiring story of survival.

GREENFIELDBOYCE: There's been a lot of work to save these fish. It's sometimes been controversial. One lawsuit about protecting their lonely pool from underground pumping went all the way to the Supreme Court. But love them or hate them, Beissinger says, you've got to admire their tenacity.

BEISSINGER: You've got to admire that - something that can cling on and adapt to such a difficult environment with nowhere to go.

GREENFIELDBOYCE: Climate change could make Devil's Hole even hotter, but he thinks the fish could keep on keeping on as long as they get a little help now and then.

Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.