1 The Great Basin Naturalist Published at Provo, Utah, by Brigham Young University ISSN Volume 38 June 30, 1978 No. 2 KAIPAROWITS FLORA Stanley L. Wel...
1 The Great Basin Naturalist Published at Provo, Utah, by Brigham Young University ISSN Volume 38 June 30, 1978 No. 2 KAIPAROWITS FLORA Stanley L. Wel...
1 GREAT BASIN GOPHER SNAKE Pituophis catenifer deserticola Original 1 prepared by Nadine Bertram Species Information Taxonomy The Gopher Snake (Pituop...
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1 Great Basin Naturalist Volume 38 Number 2 Article Kaiparowits flora Stanley L. Welsh Brigham Young University N. Duane Atwood Bureau of Land Managem...
1 Great Basin Naturalist Volume 32 Number 3 Article Scorpions of Utah John D. Johnson San Jose City College, San Jose, California Dorald M. Allred Bri...
1 Geotectonic evolution of the Great Basin William R. Dickinson Department of Geosciences, Box , University of Arizona, Tucson, Arizona 85721, USA ABS...
1 JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 101, NO. B8, PAGES 17,425-17,445, AUGUST 10, 1996 Evolution of a mafic volcanic field in the central Great Bas...
1 PROCEEDINGS, 42nd Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, February 13-15, 2017 SGP-TR-212 Conceptual...
1 Artículo "Glaciolacustrine sediments and Neoglacial history of the Chephren Lake basin, Banff National Park, Alberta" Randy W. Dirs...
Great Basin National Park National Park Service U.S. Department of the Interior
The Resource Management Newsletter of Great Basin National Park
Resurvey of GLORIA Peaks in Great Basin National Park
Photo by Adelia Barber
By Gretchen Baker, Ecologist, Meg Horner, Supervisory Biologcal Science Technician, and Adelia Barber, GLORIA Coordinator Where might you be able to easily see climate change impacts? Mountain tops are one place, due to their restricted area, extreme climate, and short growing season. This combination of factors can make plants and animals more vulnerable to changes. To better study this habitat, Great Basin National Park (GRBA) joined a worldwide coalition called the Global Observation Research Initiative Figure 1. The 2013 GLORIA resurvey crew on Buck Mountain, with Jeff Davis and in Alpine Environments (GLORIA) in Wheeler peaks in the background. The survey found 13 additional species in 2013. Primary resurvey methods included: family from the 2008 survey. The 2008. 1) Documenting plant species and most common species were in the abundance in 1 x 1 m grids, 10m Grass and Rose families. Only one The GLORIA protocol uses a x 10m quadrats, and section area species was endemic to the Snake standardized approach to collect summits; 2) Installing dataloggers Range, Holgrem’s buckwheat quantitative data on species richness to record soil temperature on (Eriogonum holmgrenii). and composition, vegetation cover, each aspect of the peaks and soil temperature, and length of snow downloading past dataloggers; and Of the four peaks, Bald Mountain cover period. It also assesses the 3) Photo documentation of all grid had the highest plant diversity, with potential for loss of biodiversity due points and datalogger locations. 54 species, while Wheeler Peak had to climate change by comparing the the lowest, with just 15 species. current distribution patterns of species, The sampling design followed the Continued on page 2 vegetation, and environmental factors GLORIA field manual (Pauli et al. along vertical and horizontal gradients. 2011). Some changes were made to allow for sampling trees on Buck Mountain and to shift quadrats to Fifty-six target regions have been established in mountain ranges around include measureable vegetation. Resurvey of GLORIA Peaks........1 the world, with 11 in the western Black Fire Rehabilitation Efforts..3 The 2013 resurvey was completed United States. Great Basin National Recreational Fishing...................4 New Geology Map....................5 in six days with a large crew Park, located in east-central Nevada, Ecosystem Restoration Effects....6 contains four of the ten highest peaks (Figure 1). All four of the GLORIA New Publications.......................7 peaks (Wheeler, Pyramid, Bald, and in Nevada and is the only target New Aspen Report.................8 region located in the state. The initial Buck) were resampled. SeventyLehman Cave Lint Camp...........8 five plant species from 23 families survey was completed in 2008, with Species of Concern..................9 a resurvey scheduled every five years were found within the plots, an Stalagmites Show Past Climate.10 increase of 13 species and one thereafter.
In This Issue
Issue 14 Volume 1
GLORIA Resurvey (continued) Number of Species Peak
endemic Eriogonum holmgrenii
most woody species most diversity
Table 1. Summary of plant species found on GLORIA peaks in Great Basin National Park in 2008 and 2013, with number of changes including species added and not found, as well as number of species found only on that peak.
All the peaks showed an increase in number of species from 2008 (Table 1). Six plant species were found on all the mountain peaks. The four Great Basin peaks were compared to other peaks in the GLORIA program in California (Figure 2). Wheeler Peak has among the lowest species richness of the 21 peaks, but Bald Mountain is the second highest. Dataloggers were downloaded during the 2013 resurvey. Analyzing temperature data only for complete years, Buck Mountain (3347 m) was the warmest peak, while Wheeler
Peak (3981 m) was coolest. Some of the species documented in 2013 appear to be new species to the target region or summit, as they would have been difficult to overlook in 2008, especially Solidago multiradiata (Figure 3). These appearances indicate that these species may be shifting upward in elevation to cooler, moister locales. The park thanks all those that assisted with the GLORIA resurvey. GLORIA monitoring is long-term commitment, requiring people who are familiar with sampling protocols and who have excellent botanical
skills. Partnerships are essential to find the expertise needed to accurately sample sites and help foster a wider appreciation of the GLORIA site so the project will continue long into the future. Literature cited Pauli, H., M. Gottfried, D. Hohenwallner, K. Reiter, R. Casale, and G. Grabherr, eds. 2011. The GLORIA field manual-multi-summit approach. European Commission. http://www.gloria.ac.at/
60 Bald Mountain 2013 Resurvey
NPS Photo by Gretchen Baker
Number of Species
50 1st Survey Data 5 years later
30 20 Wheeler Peak 2008 Survey
10 0 3000
3500 4000 Elevation (meters)
Figure 2. Comparison of species richness among GLORIA peaks in California and Nevada. Peaks in Great Basin National Park are shown in blue.
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Figure 3. Solidago multiradiata is one species detected in 2013 that was not found in 2008.
Black Fire Rehabilitation and New Trailheads Black Fire Rehab
Map of Black Fire perimeter, temporary trailheads, and rehabilitation areas. The Black Fire burned in the Lexington Arch area in 2013.
By Ben Roberts, Chief of Natural Resource Management On July 1, 2013 a lightning strike in the Black Canyon drainage, located outside the park in the BLM-managed Highland Ridge Wilderness, caused an ignition in piñon-juniper vegetation. The fire was initially monitored for resource benefit but then suppressed when it crossed pre-determined management decision lines. The fire was declared contained on September 3, 2013 after burning 96 acres of private land, 1,081 acres managed by the park, and 3,724 acres managed by the BLM. Park and BLM staff
submitted a restoration plan on September 24, which was partially funded this spring, to carry out seeding, weed surveys and treatment, and minor facilities repair, including erosion control. The BLM and NPS have established temporary road and trail closures for visitor safety and resource concerns. After safety considerations are met, and road and trail maintenance occur, the roads and trails will be reopened at temporary trailheads on both the North and South Forks of Lexington Canyon. The South Fork trailhead to Lexington Arch will be approximately one mile below the
original trailhead. Please ask at either visitor center for the most recent information. The fire on NPS lands was a mosaic of low, medium, and high intensity fire. Most of the fire was in high elevation areas consisting of mixed conifer and aspen forest types. Fires like the Black Fire are natural events and are very beneficial to natural ecosystems. Multiple fires over multiple years allow for increased patch heterogeneity, reduced forest pest outbreaks, reduced fuel loads, and increased vegetation and wildlife diversity. The Midden 3
Abundant Fish near Park Campgrounds
Surveys sites were located on Baker Creek between 6,825 and 9,000 feet elevation. Only a single brown trout was captured at the lowest site on Baker Creek. This is because the section of Baker Creek below 6,975 feet temporarily went dry in 2011, and fish are still slowly recolonizing the area. The next two sites were located at 7,175 and 7,650 feet, near Grey Cliffs and Baker Creek campgrounds, respectively. A mix of brook, brown, and rainbow trout were caught over these two sites, with the fish density estimates ranging from 2,800 to 3,765 fish per mile. The fourth site was located upstream of the Baker Creek trailhead at 8,350 feet. Only brook trout were caught and the estimated density for the site was 1,867 fish per mile. The fifth and final site on Baker Creek was located at 9,000 feet. A single brook trout was captured and the fish density was estimated to be 32 fish per mile. When all five sites on Baker Creek are averaged, the fish density is estimated at 1,925 fish per mile. The survey sites on Lehman Creek were located between 6,600 and 9,000 feet elevation. Brown trout dominated the two lowest sites 4 The Midden
A brook trout captured between Upper and Lower Lehman campgrounds.
NPS Photo by Jonathan Reynolds
In the summer of 2013, the Great Basin National Park fish crew conducted extensive fish population surveys on Baker and Lehman creeks. Using a Smith-Root LR-24 backpack electrofisher, NPS staff performed 50 meter (164 feet), three pass depletion surveys at five sites on Baker Creek and six sites on Lehman Creek.
NPS Photo by Jonathan Reynolds
By Jonathan Reynolds, Biological Science Technician
A brown trout captured near Lower Lehman Campground.
located at 6,600 and 6,975 feet. The population density estimates for these sites ranged from 2,293 to 3,347 fish per mile. The third site was located at 7,400 feet between Upper and Lower Lehman campgrounds. Brook, brown, and rainbow trout were all captured at this site, producing a population estimate of 2,478 fish per mile. The fourth, fifth, and sixth sites were located above Upper Lehman Campground at elevations of 7,900, 8,475, and 9,000 feet, respectively. With the exception of one rainbow trout, only brook trout were caught and the population densities were estimated as follows: 3,283 fish per mile at site four, 2,317 fish per mile at site five, and 2,382 fish per mile at site six. Using the estimates from all six sites, the average fish per mile for Lehman Creek was 2,684. Both Baker and Lehman creeks contain healthy populations of non-native, naturally reproducing
trout. Brown trout are the dominant species below 7,000 feet, brook trout dominate above 8,000 feet, and a mix of the two species can be found between 7,000 and 8,000 feet. Rainbow trout were dispersed between the elevations of 6,600 and 7,900 in substantially lower numbers than brook or brown trout. These surveys showed that even without supplemental stocking, Great Basin National Park offers exceptional recreational fishing opportunities in and around its most heavily used campgrounds. The park is also home to native Bonneville cutthroat trout in five streams.
Lehman Creek streamflow is now available online at: http:// waterdata.usgs.gov/nv/nwis/ uv?site_no=10243260
Park Geology Report Released Geologic Map of Great Basin National Park Nevada
Geologic Resources Inventory Qoa
The park is pleased to announce that the Geologic Resource Division of the National Park Service (NPS) has completed the Geologic Resources Inventory (GRI) for the park.
Qa Tc Qoa
Zmsc CZpm Jg
Qg Zmoa BL
Great Basin Visitor Center
n ic Sce
D r iv e
W h eel e r
Lehman Caves Visitor Center
The GRI is one of 12 inventories funded by the NPS Inventory and Monitoring Program. This report synthesizes ten years of work beginning with a scoping meeting held in September 2003 to determine geologic resources, the status of geologic mapping, and geologic resource management issues and needs.
Jeff Davis Peak 12771ft 3893m
Wheeler Peak 13063ft 3982m
CZpm Qg Kgr
Op Lexington Arch 8270ft 2521m
Granite Peak 11218ft 3419m
Qoa Qoa NPS Boundary
Geologic Units Kgr
Zmoa Osceola Argillite of the McCoy Creek Group
Oph Pogonip Group, House Limestone
Zmsc McCoy Creek Group, Shingle Creek Shale
PNe Ely Limestone
OCn Notch Peak Limesetone
Zmq McCoy Creek Group, quartzite
Corset Spring Shale
Johns Wash Limestone
Lincoln Peak Formation
Linear Marker Beds Tcmb- Conglomerate, marker bed, known or certain
Qoa Older alluvium
MDp Pilot Shale
Pogonip Group, Fillmore Limestone
Clpmb - Lincoln Peak Formation, marker bed, known or certain
Cpc Pole Canyon Limestone, undifferentiated
Cpcmb - Pole Canyon Limestone, undifferentiated, marker bed, known or certain
Cpce Pole Canyon Limestone, E member
Cpcd Pole Canyon Limestone, D member
Linear Dikes Tmp - Muscovite-bearing rhyolite porphyry dikes and sills, known or certain Faults normal fault or detachment fault/decollement, solid where known, dashed where approximate or inferred, dotted where concealed, and ‘?’ indicates queried Geologic Contacts solid where known, dashed where approximate or inferred, dotted where concealed
The GRI is a companion document to the previously completed digital geologic map. The report, the initial scoping document, a printable map, map properties table, GIS data, and a Google Earth file can be accessed and downloaded at the following location:
National Park Service U.S. Department of the Interior
By Ben Roberts, Chief of Natural Resource Management
Needles Range Formation
OSfl Fish Haven and Laketown Dolomites, undifferentiated
Trdi Rhyodacite flows and subvolcanic intrusive rocks Toc Older conglomerate Tmp Muscovite-bearing rhyolite porphyry dikes and sills Tgr
Pogonip Group, undifferentiated
Pogonip Group, Lehman Formation
Opk Pogonip Group, Kanosh Shale Opj
Pogonip Group, Juab Limestone
Opw Pogonip Group, Wahwah Limestone
Cpcc Pole Canyon Limestone, C member Cpcb Pole Canyon Limestone, B member Cpca Pole Canyon Limestone, A member Cpi
CZpm Prospect Mountain Quartzite Zm
McCoy Creek Group, undifferentiated
3 Kilometers Miles
This figure is an overview of compiled digital geologic data. It is not a substitute for site-specific investigations. Minor inaccuracies may exist regarding the location of geologic features relative to other geologic or geographic features on the figure. Based on the source map scale (1:24,000) and U.S. National Map Accuracy Standards, geologic features represented here are within 12 meters / 40 feet (horizontally) of their true location. This figure was prepared as part of the NPS Geologic Resources Division’s Geologic Resources Inventory. The source map used in creation of the digital geologic data product was: Miller, E.L, and the Stanford Geological Survey. 2007 (mapping 1993-1997). Geologic Map of Great Basin National Park and Environs, Southern Snake Range, Nevada (1:24,000 scale). Stanford Geological Survey. Digital geologic data and cross sections for Great Basin National Park, and all other digital geologic data prepared as part of the Geologic Resources Inventory, are available online at the NPS Integrated Resource Management Applications Portal (IRMA): https://irma.nps.gov/App/Reference/Search. (Enter “GRI” as the search text and select Great Basin National Park from the unit list.)
The Midden 5
Ecosystem Restoration Effects on Small Mammals By Bryan Hamilton, Wildlife Biologist Sagebrush communities have declined dramatically across the Great Basin, while the extent of piñon-juniper woodlands has increased by an order of magnitude. Piñon-juniper encroachment is a major driver of sagebrush habitat loss. Therefore, sagebrush restoration efforts have focused primarily on reducing tree encroachment by thinning encroaching conifers.
NPS Photos by Bryan Hamilton
Small mammals are important components of biodiversity and ecological function in the Great Basin. Seed caching by small mammals enhances plant germination, and burrowing aerates soils, cycles nutrients, and maintains early seral state plant communities. As the prey base for many predators, small mammals are important links in food webs. Despite their importance to ecosystems, the effects of sagebrush restoration on small mammals has received very little attention relative to other taxa such as birds and big game. To restore sagebrush habitat, Great Basin National Park treated over 100 acres between 2004 and 2007. Treatments involved cutting trees, chipping or pile burning slash, and reseeding native vegetation. To evaluate the effects of sagebrush restoration on small mammal diversity, a Before, After, Control, Impact (BACI) design was used. This design can establish casual relationships between thinning, annual grasses, small mammal diversity, and tree encroachment. Continued on page 7 6 The Midden
Figure 1. Tree encroachment (top photo) is reduced immediately after thinning treatments (bottom photo). Reduced tree cover leads to increased herbaceous vegetation and small mammal abundance.
Ecosystem Restoration Effects on Small Mammals (cont.) As expected, thinning significantly reduced tree cover (P = 0.0010; Figure 1). Shrub cover remained unchanged on both treated and untreated sites (P = 0.086). Herbaceous cover significantly increased on treated plots and was unchanged on untreated plots (P < 0.0001). This increase in herbaceous cover was driven primarily by invasive annual grasses (44%). Even when annual grasses were removed from the analysis, the increase in herbaceous cover remained significant, but at a reduced magnitude (P = 0.0002). Prior to treatments, small mammals were more abundant on sites with minimal tree encroachment. Nearly
twice as many small mammals were found on less encroached sites than sites with high tree encroachment (15 versus 8 per hectare). Treatments had no effects on small mammal abundance, richness, evenness, or biomass (P > 0.05). Sagebrush-dependent small mammals (harvest mice and sagebrush voles) increased on treated sites, while piñon mice decreased. However these results were statistically significant only for harvest mice.While past studies on tree thinning in shrub habitat have similarly shown minimal effects of thinning on small mammals, these studies did not employ a BACI design, limiting their ability to assert causal
relationships. Our results support the conclusion that restoration treatments do not negatively impact small mammals, with a caveat that treatments were small in scale relative to some restoration efforts. Ultimately, by decreasing tree cover and increasing shrub and herbaceous cover, restoration should eventually increase small mammal abundance. Higher small mammal abundance may have trophic consequences. Small mammal abundance could cascade upward to benefit predators such as Great Basin rattlesnakes, raptors, and mesocarnivores, and cascade downward to impact plants, soils, and ecosystem processes.
Recent Publications about Great Basin National Park Eagles-Smith, C. A., J. J. Willacker, and C. M. Flanagan-Pritz. 2014. Mercury in fishes from 21 national parks in the Western United States—Inter and intra-park variation in concentrations and ecological risk: U.S. Geological Open-File Report 2014-1051, 54 p. http://pubs.er.usgs.gov/publication/ofr20141051 Graham, J. P. 2014. Great Basin National Park: Geologic resources inventory report. Natural Resource Report NPS/NRSS/GRD/NRR—2014/762. National Park Service, Fort Collins, Colorado. http://www.nature.nps.gov/geology/inventory/gre_publications.cfm Hollenhorst, J. 2014. Lehman Caves: Time capsule of nature etched in stone and bone. KSL News, Salt Lake City, Utah. http://www.ksl.com/?nid=148&sid=29376634 Horner, M. A., B. T. Hamilton, and L. Provencher. 2014. Great Basin National Park aspen stand condition and health assessment. Natural Resource Report NPS/GRBA/NRR—2014/782. National Park Service, Fort Collins, Colorado. http://www.nature.nps.gov/publications/nrpm/nrr.cfm Jageman, Karla. 2014. The boom and bust of tungsten mining: a view from the Johnson Lake Historic Mining District. MA thesis, University of Leicester, England. Lachniet, M. S., R. F. Denniston, Y. Asmerom, and V. J. Polyak. 2014. Orbital control of western North America atmospheric circulation and climate over two glacial cycles. Nature Communications 5 (3805): 1-8. Volk, John M. 2014. Potential effects of a warming climate on water resources within the Lehman and Baker Creek drainages, Great Basin National Park, Nevada. MS Thesis, University of Nevada, Reno. Wright, G., M. S. Gustin, P. Weiss-Penzias, and M. B. Miller. 2014. Investigation of mercury deposition and potential sources at six sites from the Pacific Coast to the Great Basin, USA. Science of the Total Environment: 1099-1113. The Midden 7
Natural Resource Report on Aspen Stand Condition and Health by Meg Horner, Supervisory Biological Science Technician and Bryan Hamilton, Wildlife Biologist
Aspen systems represent the largest vegetation type in the park covering 27.3% of park lands; but as a result of fire suppression, aspen stands have converted to conifer on over 1,200 acres. Under current management practices, park aspen condition will continue to deteriorate. Within 50 years, the conversion of aspen to conifer is predicted to result in a permanent
NPS Photo by Meg Horner
Quaking aspen (Populus tremuloides) is the most widely distributed tree species in North America and is regarded as a keystone species because it supports a high diversity of flora and fauna. Nevertheless, aspen are declining throughout the West, including within Great Basin National Park. To determine the status of park aspen, assess stand condition, and develop management strategies for restoration, the park partnered with The Nature Conservancy to perform Landscape Conservation ForecastingTM. View of aspen stands in the fall from the Mather Overlook.
loss of aspen from approximately 10,000 acres. Restoration strategies include prescribed fire to correct ecological departure and prevent conversion of aspen to conifer. Ecological restoration using prescribed fire is recommended for nine park watersheds, totaling 14,174 acres.
The park has published a Natural Resources Report outlining potential restoration areas and applicable restoration strategies. You can find the report, Great Basin National Park Aspen Stand Condition and Health Assessment, at http://www.nature.nps. gov/publications/nrpm/nrr.cfm.
2014 Lint Camp Removes over Two Tons of Sand and Debris pounds of old trail debris, particularly sand, that had covered formations. Thirty-seven volunteers from Nevada, They used brushes and dust pans to Utah, California, Idaho, Canada, and collect sand into five-gallon buckets, Australia gathered the weekend of which were then carried or wheeled March 21-23, 2014 in Great Basin out of the cave one or two buckets at a National Park to help clean Lehman time. Cave during the annual lint camp. Participants picked lint from cave The park is planning to hold another formations and walls along 600 lint and restoration camp next year, feet of passage and treated algae continuing to engage park visitors in accumulations near lights. In addition, innovative ways to celebrate the upvolunteers carried out over 4,000 coming NPS Centennial in 2016. 8 The Midden
NPS Photo by Gretchen Baker
By Gretchen Baker, Ecologist
One of the many young volunteers at the 2014 lint camp. This participant was able to remove a great deal of lint from one of the seven staircases in the cave.
Species of Management Concern Update
Resource Management staff at Great Basin National Park are updating the park’s list of species of management concern. The list includes species of mammals, birds, reptiles, amphibians, invertebrates, and plants that meet one of the following criteria: local rarity, endemism, importance to the park, vulnerability to local population declines, usefulness as an indicator species, sensitivity to human disturbance during critical portions of its life cycle, and/or the focus of unusual public interest or political concern.
the updated sensitive species list and find out more about the species of wildlife and plants found in the park – http://www. nps.gov/grba/naturescience/index.htm.
NPS Photo by Bryan Hamilton
By Meg Horner, Supervisory Biological Science Technician
And if you encounter wildlife during your visit, please fill out a Wildlife Observation Form located at one of the park’s visitor centers. Figure 1. A Sonoran mountain kingsnake, one species of management concern at Great Basin National Park.
The last update was in 2006, and since then, surveys have shed light on the presence, distribution, and status of several species. A variety of survey and monitoring methods have been used to sample local wildlife and plants: small mammal trapping; remote camera surveys; visual encounter surveys for reptiles (Figure 1), pygmy rabbits, and yellow-bellied marmots; acoustic and mist-net surveys for bats; monitoring bighorn sheep with satellite-linked GPS collars; fish population surveys; broadcast surveys for Northern goshawk; breeding bird surveys; cave invertebrate surveys; and rare plant surveys. Wildlife observations made by park staff and visitors from in and around the park have also added to the known distribution for some species and helped inform several changes to the list. Over 41,000 geo-referenced locations have been recorded for 207 species of wildlife (Figure 2). Check out the park website to view
Figure 2. Map of wildlife observations in Great Basin National Park. The Midden 9
The Midden is the Resource Management newsletter for Great Basin National Park. A spring/summer and fall/winter issue are printed each year. The Midden is also available on the Park’s website at www.nps.gov/grba. We welcome submissions of articles or drawings relating to natural and cultural resource management and research in the park. They can be sent to: Resource Management, Great Basin National Park, Baker, NV 89311 Or call us at: (775) 234-7331 Superintendent Steven Mietz Chief of Resource Management Tod Williams Editor & Layout Gretchen Baker
What’s a midden?
A midden is a fancy name for a pile of trash, often left by pack rats. Pack rats leave middens near their nests, which may be continuously occupied for hundreds, or even thousands, of years. Each layer of trash contains twigs, seeds, animal bones and other material, which is cemented together by urine. Over time, the midden becomes a treasure trove of information for plant ecologists, climate change scientists and others who want to learn about past climatic conditions and vegetation patterns dating back as far as 25,000 years. Great Basin National Park contains numerous middens.
Stalagmites Reveal Past Climate History By Matthew Lachniet, University of Nevada, Las Vegas Three stalagmites from Lehman Cave, along with two others from Pinnacle and Leviathan caves in Nevada, have been age dated with uranium series and oxygen isotopes to help determine the past climate history in the Great Basin. Stalagmites grow in air-filled caves from dripping water and act as ancient rain gauges to help researchers form a more precise chronological record of climate history. Calcite minerals from tiny drops of water accumulate over thousands of years and, much like tree rings, accurately record the precipitation history of an area. The record produced in this study is the first long-term and continuous record that shows unambiguously that the Great Basin climate was paced by the Earth’s orbit around the sun. Our team was able to show that sea surface temperatures off the coast of California did not control Great Basin climate as was suggested by the prevailing hypothesis, based on work at Devil’s Hole in California. Instead, this new research shows that the controls on Great Basin climate are instead related to snow and ice cover on land.
NPS Photo by Gretchen Baker
National Park Service U.S. Department of the Interior
Cave formations store past climate history. Only previously broken stalagmites in Lehman Cave were used for this research.
In addition, the new research shows that the growth of the iconic pluvial lakes in the Great Basin were controlled by the metronomic pulsing of climate changes linked to Earth’s orbit. The pluvial lakes were huge lakes that covered a large portion of northern Nevada and Utah during the last ice age when climate was much wetter than today. The Great Salt Lake of Utah is a tiny remnant of Lake Bonneville, one of the past lakes in this area. Based on this relationship of the variations in the Earth’s orbit and Nevada’s climate, our team suggests that the region won’t see the reappearance of these pluvial lakes for at least another 55,000 years. These findings are presented in more detail in the journal Nature Communications.
Upcoming Events: June 12, July 12, August 10, September 8 Full moon hikes: Call 775-2347331 for details July 13-15 Lepidoptera BioBlitz: Look for butterflies and moths during the sixth annual BioBlitz open to professionals and citizen scientists. Contact Gretchen_ [email protected] August 12 Perseids Meteor Shower: Watch the year’s most active meteor shower with Great Basin’s Dark Sky Rangers September 18-20 Astronomy Festival: Peer though many telescopes at some of the darkest night skies in the nation. Check the park website for details. October 31 Sesquicentennial of Nevada: Nevada’s 150th birthday