{{Short description|Spring in Nye County, Nevada, United States}} {{Other uses}} {{Use American English|date=July 2025}} {{Use mdy dates|date=July 2023}} right|thumb|upright=1.15|Looking into Devils Hole; the dark area is the surface of the water. '''Devils Hole''' is a geologic formation located in a detached unit of Death Valley National Park and surrounded by the Ash Meadows National Wildlife Refuge, in Nye County, Nevada, in the Southwestern United States.

Devils Hole is habitat for the only naturally occurring population of the endangered Devils Hole pupfish (''Cyprinodon diabolis''). The {{convert|40|acre|ha|abbr=on}} unit is part of the Ash Meadows complex, an area of desert uplands and spring-fed oases that was designated as a National Wildlife Refuge in 1984. In 1952 President Harry Truman added Devils Hole to what was then Death Valley National Monument.<ref>{{Cite web |last=Rivard |first=Katherine |title=The Extraordinary Lives of Death Valley's Endangered Devils Hole Pupfish |url=https://www.nationalparks.org/connect/blog/extraordinary-lives-death-valleys-endangered-devils-hole-pupfish |access-date=2024-09-25 |website=National Park Foundation |language=en}}</ref><ref>{{Cite web |title=Devils Hole - Death Valley National Park |url=https://www.nps.gov/deva/learn/nature/devils-hole.htm |access-date=2024-09-25 |website=National Park Service |language=en}}</ref>

==Description== Devils Hole is a geothermal pool within a limestone cavern in the Amargosa Desert in the Amargosa Valley of Nevada, east over the Amargosa Range and Funeral Mountains from Death Valley. It is at an elevation of {{cvt|730|m|ft}} above sea level<ref name="Baugh">{{cite journal|jstor=41712019|title=Daily and Yearly Movement of the Devil's Hole Pupfish Cyprinodon Diabolis Wales in Devil's Hole, Nevada|journal=The Great Basin Naturalist|volume=43|issue=4|pages=592–596|last1=Baugh|first1=Thomas M.|last2=Deacon|first2=James E.|year=1983}}</ref> and the water is a constant temperature of {{cvt|33|C|F}}.<ref name="Andersen"/> The surface area of Devils Hole is about 22 m long by 3.5 m wide (72&nbsp;ft long by 11.5&nbsp;ft wide). Approximately {{cvt|0.3|m|ft|1}} deep on one end of Devils Hole is a small rock shelf of {{cvt|3.5|by|5|m|ft}}. The dissolved oxygen of the water is 2.5&ndash;3.0 ppm up to around {{cvt|22|m|ft}} in depth, though the shallow shelf can have dissolved oxygen levels as high as 6.0&ndash;7.0 ppm in June and July.<ref name="Baugh"/> right|thumb|A viewing platform overlooks the hole.

Devils Hole branches into caverns at least {{cvt|130|m|ft}} deep,<ref name="Andersen">{{cite journal|doi=10.1643/0045-8511(2001)001[0224:PSODHP]2.0.CO;2|issn=0045-8511|year=2001|volume=1|pages=224–228|title=Population Size of Devils Hole Pupfish (Cyprinodon diabolis) Correlates with Water Level|journal=Copeia|last1=Andersen|first1=Matthew E.|last2=Deacon|first2=James E.|s2cid=85845126 }}</ref> whose bottom has never been mapped.<ref name=NPS /> According to geologists, the caves were formed over 500,000 years ago.<ref>{{cite web|last1=Landwehr|first1=J.M.|last2=Winograd|first2=I.J.|year=2012|title=Devils Hole, Nevada—A Primer|publisher=U.S. Geological Survey|id=Fact Sheet 2012–3021|url=https://pubs.usgs.gov/fs/2012/3021|access-date = 2013-01-17 }}</ref> The pool has frequently experienced seiche activity due to far away earthquakes in Japan, Indonesia, Mexico, and Chile, which have been likened to extremely small scale tsunamis.<ref name=NPS>{{cite web|url=https://www.nps.gov/deva/naturescience/devils-hole.htm|title=Devils Hole|publisher=National Park Service|access-date=28 January 2014}}</ref>

Below the surface pool, Devils Hole descends approximately {{convert|160|ft|m|-1}} through what is termed the "main chamber" before reaching a narrow opening referred to as the "funnel". Through this opening lies a much larger chamber of the cavern system known as Acree's Chasm. Acree's Chasm is approximately {{convert|300|ft|m}} in length, {{convert|40|ft|m}} in width, and has a bottom approximately {{convert|260|ft|m|-1}} below the surface.<ref name=Hoffman>{{cite report|last=Hoffman|first=RJ|title=Chronology of Diving Activities and Underground Surveys in Devils Hole and Devils Hole Cave, Nye County, Nevada, 1950-86|publisher=USGS|id=Open File Report 88-93|year=1988|url=https://pubs.usgs.gov/of/1988/0093/report.pdf}}</ref><ref name=Riggs>{{cite conference|first1=AC|last1=Riggs|first2=JE|last2=Deacon|title=Connectivity in Desert Aquatic Ecosystems: The Devils Hole Story|conference=Spring-fed Wetlands: Important Scientific and Cultural Resources of the Intermountain Region|year=2002|citeseerx=10.1.1.546.1508 }}</ref>

Immediately after passing the funnel into Acree's Chamber, a narrow side tube can be found to a diver's left. This side tube proceeds approximately {{convert|90|ft|m}} upward to a chamber with an air pocket, named Brown's Room. The tube leading to Brown's Room has at least 2 offshoots, the higher of which leads to a dead-end filled with a small air pocket, and the lower of which joins with additional tubes descending from Brown's Room.<ref name=Hoffman/> If the diver instead descends through Acree's Chamber, the first notable landmark is a rocky shelf termed the "lower ledge", around {{convert|100|ft|m}} below the entrance to the chamber. The bottom of Acree's Chamber lies around {{convert|260|ft|m}} below the surface, but is not flat. Instead, a portion of the chamber floor descends below this lower shelf; a gradual funnel leads to a hole in the bottom of the chamber featuring a strong current. The hole, later termed the ''ojo de agua'', is {{convert|315|ft|m}} below the surface and just large enough for a diver with equipment to fit through.

On June 20, 1965, Paul Giancontieri, a teenager who had jumped the fence with friends to go SCUBA diving in the hole, did not come back up.<ref name="Stringfellow 2015 P1">{{Cite web |title=Divining Devils Hole: Part I |url=https://mojaveproject.org/dispatches-item/divining-devils-hole-part-1/ |website=The Mojave Project|author=Stringfellow |date=October 2015|first=Kim}}</ref> His brother-in-law David Rose went down to find him but did not resurface either.<ref name="Stringfellow 2015 P1" /> An effort by five divers to find their bodies three days later was unsuccessful.<ref>{{cite news |title=Divers Halt Search For Missing Youths |url=https://www.newspapers.com/clip/105256943/divers-halt-search-for-missing-youths/|via=Newspapers.com |work=Redwood City Tribune |date=June 23, 1965 |page=18|url-access=limited|agency=Associated Press}}</ref>

On June 20, 1965, during the second dive of a rescue and then body recovery mission, Jim Houtz with his dive partner dropped a weighted depth line to a depth of {{convert|932|ft|m}} from the start of this opening, without hitting the bottom of the chamber below. Due to the strong current, the small size of the entrance, and the unknown depth of the cavern below, which Houtz termed the "Infinity Room", Jim and his partner chose not to explore this Infinity Room. This mission did, however, confirm that the Infinity Room of Devil's Hole, and the cavern system itself, has a depth of at least {{convert|1247|ft|m}} from the surface.<ref>{{cite web|title=Mojave Project: Divining Devils Hole|url=https://www.kcet.org/shows/artbound/mojave-project-divining-devils-hole|publisher=KCET|first=Kim|last=Stringfellow|date=October 4, 2015}}</ref><ref name=Riggs/>{{Failed verification|date=March 2026}}

thumb|Updated diagram of Devils Hole (2005)

A subsequent USGS exploration into Devil's Hole in 1991 by Alan Riggs, Paul DeLoach, and Sheck Exley entered what they found out to be a narrow tube rather than an "Infinity Room" at {{convert|315|ft|m}}, descending to a depth of {{convert|436|ft|m}}. The team reported being able to see down to a depth of some {{convert|500|ft|m}}, without visualizing the bottom of the cavern.<ref name="Riggs" />

On March 20, 2012, a 7.4-magnitude earthquake in Oaxaca, Mexico, some {{convert|2000|mi|km}} away and centered roughly {{convert|12|mi|km}} below the surface, caused an undulating {{convert|4|ft|m}} rise and fall of the cavern waters, as appreciated by researchers working at Devil's Hole at the time. This provided further evidence that the Devil's Hole cave system was connected not only to the Death Valley Regional Groundwater Flow System, but possibly to even further-reaching underground water systems.{{Citation needed|reason=seiches don't require further-reaching underground water systems and may occur even in swimming pools|date=October 2022}} The 1991 USGS dive team described the Devil's Hole as a "skylight" into the water table.<ref name="Riggs" />

A team of paleoclimatologists from the University of Innsbruck have been collecting and dating calcite mineral deposits here since 2010.<ref>{{Cite web|title=DEVILS HOLE|url=https://www.uibk.ac.at/newsroom/dossiers/devilshole/|access-date=2022-01-31|website=University of Innsbruck}}</ref> In March 2017, underwater cinematographer Jonathan Bird received permission to assist scientists in a four-day expedition to take water and calcite core samples.<ref name=":0">{{Cite web|date=2017-03-03|title=Researchers diving deep into Devil's Hole to study climate history|url=https://pvtimes.com/news/researchers-diving-deep-into-devils-hole-to-study-climate-history/|access-date=2022-01-31|website=Pahrump Valley Times|language=en-US}}</ref> The IMAX footage was included in the 2020 film ''Ancient Caves'' and extra footage was used to create the video documentary ''Exploring Devils Hole''.<ref>{{YouTube|2QGTKKws3gM|Exploring Devils Hole}}</ref>

There had been similar studies in Devil's Hole, but these are no longer permitted due to the endangered status of the Devils Hole pupfish.<ref name=":0" /> Cleaning and disinfection of diving equipment, climbing gear, cameras, etc. using hot water and Steramine followed by at least 30 days of air-drying is required by the National Park Service to prevent contamination of the underwater ecosystem.<ref>{{Citation|work=Dive Talk|title=DIVERS REACT TO DEVIL'S HOLE DEATHS (a story by MrBallen)|url=https://www.youtube.com/watch?v=t0T7StMqQUQ&t=28m0s|language=en|access-date=2022-02-01}}</ref>

On September 19, 2022, a seiche reaching {{Convert|4|ft|m|abbr=off}} occurred at Devils Hole after a 7.6-magnitude earthquake hit western Mexico, about {{Convert|1500|mi|km|abbr=off}} away. Seiches were also observed in the cave after powerful earthquakes in 2012, 2018, 2019,<ref name="BNO">{{Cite web |date=September 21, 2022 |title=Mexico earthquake caused waves at California's Death Valley |url=https://bnonews.com/index.php/2022/09/mexico-earthquake-caused-waves-at-californias-death-valley/ |access-date=September 22, 2022 |website=BNO News}}</ref> and 2024.<ref>{{Citation|work=USA Today|title=Video shows impact of CA quake felt more than 500 miles away by endangered Devils Hole pupfish|url=https://www.usatoday.com/story/news/nation/2024/12/09/video-california-quake-500-miles-away-devils-hole-pupfish/76859085007/}}</ref>

==Devils Hole Cave == thumb|Diagram of Devils Hole Cave (1988) Located {{Convert|650|ft|m}} north of Devils Hole is a separate cave system called Devils Hole Cave (#2). It was first explored underwater to a depth of {{Convert|70|ft|m}} by divers from the Southwestern Speleological Society in February 1961. It had been described as being shaped like a boot with fallen rock restriction at the {{Convert|50|ft|m|adj=on}} level leading to a narrow pool of {{Convert|93|F|C|adj=on}} water.<ref name="Hoffman" /> Since no sunlight reaches the water, algae cannot grow and no fish species are found.<ref name="ancient-caves-making-of" />

On the surface, the cave openings are connected to Devils Hole by an access road and covered with a locked metal grate. Below ground, a passable deepwater connection to Devils Hole has been theorized but remains undiscovered.<ref name="ancient-caves-making-of">{{Cite AV media|url=https://www.youtube.com/watch?v=kJ6UMfcz1zk|title=Ancient Caves - The "making of" a film for IMAX and giant-screen theaters|date=2021-08-15|last=Bird|first=Jonathan|language=English|publisher=Oceanic Research Group Films|author-link=Jonathan Bird|type=video}}</ref>

==Pupfish == {{Main|Devils Hole pupfish}}

[[Image:Cyprinodon diabolis, males.jpg|thumb|Devils Hole pupfish, ''Cyprinodon diabolis'', from Death Valley National Park]] Devils Hole is the only natural habitat of the Devils Hole pupfish, which survives despite the hot, oxygen-poor water.<ref>{{Cite news |last=Greenfieldboyce |first=Nell |date=July 7, 2023 |title=Against all odds, the rare Devils Hole pupfish keeps on swimming |work=NPR News |url=https://www.npr.org/2023/07/07/1182118098/against-all-odds-the-rare-devils-hole-pupfish-keeps-on-swimming}}</ref> Devils Hole "may be the smallest habitat in the world containing the entire population of a vertebrate species".<ref name="Andersen"/> The pupfish are considered critically endangered by the IUCN.<ref name=IUCN>{{cite iucn |author = NatureServe |title = ''Cyprinodon diabolis'' |volume= 2014 |article-number = e.T6149A15362335 |year = 2014 |doi = 10.2305/IUCN.UK.2014-3.RLTS.T6149A15362335.en }}</ref> The pupfish has been described as the world's rarest fish,<ref>{{cite news |url=https://www.economist.com/news/science-and-technology/21569687-hole |title=In a hole |newspaper=The Economist|date=19 Jan 2013 |access-date=2016-05-10}}</ref> with a population of 263 as of 2022.<ref name="2022count">{{cite web |url=https://www.fws.gov/press-release/2022-09/devils-hole-pupfish-population-19-year-high |title=Devils Hole pupfish population at 19-year high |website=U.S Fish and Wildlife Service |date=30 September 2022 |publisher=United States Fish and Wildlife Service |access-date=4 October 2022}}</ref> Genetic information indicates that the pupfish species is as old as the Hole itself, which opened to the surface about 60,000 years ago.<ref>{{cite web |title = We know where the world's loneliest species came from |url = http://www.bbc.com/earth/story/20160622-the-worlds-loneliest-species |website = bbc.com |access-date = 24 June 2016 |date = 23 June 2016 |last = Walker |first = Matt}}</ref><ref>{{cite journal |last1=Sağlam |first1=İsmail K. |last2=Baumsteiger |first2=Jason |last3=Smith |first3=Matt J. |last4=Linares-Casenave |first4=Javier |last5=Nichols |first5=Andrew L. |last6=O'Rourke |first6=Sean M. |last7=Miller |first7=Michael R. |display-authors=4 |title = Phylogenetics supports an ancient common origin of two scientific icons: Devils Hole and Devils Hole pupfish |journal = Molecular Ecology |doi = 10.1111/mec.13732 |year = 2016|pmid=27314880 |volume=25 |issue = 16 |pages=3962–73 |s2cid=21832372}}</ref>

The pupfish have been protected since being declared an endangered species in 1967.<ref name=fws>{{cite web |url=http://www.fws.gov/nevada/protected_species/fish/species/dhp/dhp.html |title=Devils Hole Pupfish |publisher=U.S. Fish and Wildlife Service |date=December 2, 2013 |access-date=2016-05-14}}</ref> Conflicts of the ownership and use of the groundwater around Devils Hole caused litigation in the 1980s.<ref>{{cite book |last1=Minckley |first1=WL |last2=Deacon |first2=JE |year=1991 |title=Battle against extinction: native fish management in the American West |publisher=University of Arizona Press |location=Tucson |isbn=978-0-8165-1221-8}}</ref> The litigation triggered further protections of the pupfish. Since the late 1990s, the pupfish population has substantially decreased. The reasons for the decrease are unknown, but is possibly due to a microscopic non-indigenous diving beetle that is consuming pupfish eggs.<ref name=fws/><ref>{{cite web |last1=Bittel |first1=Jason |title=Brutal beetles kept world's rarest fish from breeding—until now |url=https://www.nationalgeographic.com/animals/2019/03/endangered-devils-hole-pupfish-breeding-breakthrough/ |archive-url=https://web.archive.org/web/20190302071616/https://www.nationalgeographic.com/animals/2019/03/endangered-devils-hole-pupfish-breeding-breakthrough/ |archive-date=March 2, 2019 |website=National Geographic |date=March 2019 |publisher=National Geographic |access-date=5 March 2019}}</ref>

==References== {{clear right}} {{Reflist|33em}}

==External links== {{Commons and category}} *{{cite gnis |id=857963 |name= Devils Hole |accessdate=2009-08-10}} *[https://www.jstor.org/pss/3671602 The Southwestern Naturalist: "Pupfish Populations"] *[https://www.youtube.com/watch?v=a6h82PIi_-0 Death Valley Natural History Association - Video of Seismic Waves in the Pool] *{{YouTube|2QGTKKws3gM|Ancient Caves - Exploring Devils Hole}} *{{IMDb title|qid=Q123536889|title=Ancient Caves|description=(IMAX 2020)}}

{{Authority control}} {{Coord|36.425312|N|116.291458|W|format=dms|region:US-NV_type:landmark_source:gnis|display=title}}

Category:Caves of Nevada Category:Springs of Nevada Category:Amargosa Desert Category:Desert National Wildlife Refuge Complex Category:Death Valley National Park Category:Bodies of water of Nye County, Nevada Category:Limestone caves