Masthead: Kaweah Range

Sierra Nature Notes Archive: Page 2

Persistence of pikas in two low-elevation national monuments in the western United States
By Erik A. Beever, Ph.D.
Ecologist, U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR 97331.

Pikas are well known to travelers in the High Sierra. Their cheery high-pitched call is often heard by hikers passing through boulder fields on an alpine pass. Occasionally pikas can be seen with a mouth full of grass getting ready for winter. Recent work by Erik Beever in the Great Basin indicates that warmer temperatures seen as a result of possible global climate change may be affecting their survival and distribution in certain areas. Preliminary population surveys are underway in the Sequoia Kings Parks to determine if pikas are being affected in the Sierra as well.

Mountain Lion and Human Interactions in Yosemite National Park
Leslie S. Chow,
Research Wildlife Biologist
Yosemite Field Station
U. S. Geological Survey

A dramatic rise in puma sightings and apparent changes in puma behavior raise concerns about increased risks to visitor safety in Yosemite National Park. How much time are pumas spending in developed areas and what are they doing while they are there?

Update (11/03): Park biologists had to euthanize two Mountain lions in Yosemite Valley because of possible danger to visitors. The lions were hunting raccoons — attracted by food left by campers — in heavily used areas. Full Story.

Family Nature Explorations — A Resource Kit
by Michael Elsohn Ross
Naturalist and Author

Children have a natural curiosity, which constantly leads them into discoveries. Parents, grandparents, and other adults who explore nature with kids can support youthful inquiry by being equipped with some handy resources.

The Naming of Beetle Rock at Giant Forest, Sequoia National Park: How the Rock got a Name, The World Discovered an Insect, and An Enthusiastic Amateur Entomologist Started a Career
by John Lockhart, Education Coordinator
Sequoia Field Institute, Sequoia Natural History Association

Meet, at long last, the Beetle of Beetle Rock: a naturalist launches a nationwide search for the elusive Trachykele opulenta Fall, 1906, that gave Sequoia Park's Beetle Rock its name.

A vegetation transect along the Sierran Pacific Crest Trail
Rob York1, Jennifer McElhaney2, John Battles2
1Center for Forestry, University of California- Berkeley.
2Dept. of Environmental Science, Policy, and Mangement, University of California- Berkeley.

Beginning at the Mexican border, the Pacific Crest Trail runs 2,650 miles along the spine of the Sierra Nevada, ending at the Canadian border. On the way, thru-hikers have a fantastic opportunity to become aware of different biomes and the conditions that foster them.

Yosemite Falls—A New Perspective
By N. King Huber

Geologist Emeritus U. S. Geological Survey.

Upper Yosemite Fall now leaps from the hanging valley of Yosemite Creek. In the not-too-distant geologic past its water cascaded down through the prominent ravine immediately to the west (left).

How has climatic variation influenced treeline dynamics in the past?
Andrea H. Lloyd

Assistant Professor, Department of Biology, Middlebury College

For most of the past 3,500 years, Sierra treeline was higher than it is today. From treerings and remnant stands of ancient Foxtail pines, scientists are able to reconstruct the climatic conditions that cause treeline to fluctuate as well as how global warming might influence treeline in the future.

Do trails fragment meadows more than we think? A bug's view.
Jeff G. Holmquist & Jutta Schmidt-Gengenbach
University of California White Mountain Research Station and Sierra Nevada Aquatic Research Lab

The authors investigate the effects of hiking trails on insects and other invertebrate populations in Sierran meadows. Become acquainted with this diverse — but almost unknown — community beneath the grasses.

Good News For Sierra Sheep
by John Wehausen, PhD
President, Sierra Nevada Bighorn Sheep Foundation

An aerial survey in Kings Canyon National Park finds a previously unknown band of Bighorn Sheep wintering there. Sheep had not been known to winter in Sequoia and Kings Canyon since the 1920s. In this short field report, Dr. Wehausen also provides current population estimates for the entire Sierra.

The Great Droughts of Y1K
Scott Stine, Ph.D
California State University, Hayward

Two severe decades-long droughts, ending about AD 1100 and AD 1350, caused major ecological changes in the west. We can still see evidence of that time in, for instance, the tips of trees showing in Yosemite's Tenaya Lake — their roots still attached under 70 feet of water. Can such droughts return?

The Soundprints Of Science
By Elizabeth F. van Mantgem
Conservation Biologist, Sequoia and Kings Canyon National Parks.

The sounds of wilderness — or their lack —are a vital part of not only our experience as visitors but, as new evidence is showing, critical to the life cycles of animals. Elizabeth van Mantgem describes the recent work of Dr. Bernie Krause working to quantify the deterioration of the biophony, or natural orchestras, in our National Parks.



The Sierra Wave
by Beth Pratt
Vice President, Yosemite Association

One of the most dramatic examples of the "poetry of clouds" Sierra visitors are often lucky to see, are lenticular clouds forming over the Sierra Crest. Beth Pratt explains the science — and poetry — of their formation.


The continuing effort to find and save the mountain yellow-legged frogs of the Sierra Nevada
by Casey Ray
Field Biologist, Sierra Nevada Aquatic Research Lab (SNARL)

For over a million years, generations of mountain yellow-legged frogs have sunned themselves on the shores of Sierran lakes. In the last 20 years, their population has been crashing. Biologists have now visited almost 8000 lakes, including all lakes of Yosemite and Sequoia-Kings Canyon National Parks, to establish a definitive survey of their numbers and range.

Fire Regimes
in Sierran Mixed-Conifer Forests

by Dr. Thomas W. Swetnam and
Mr. Christopher H. Baisan

Laboratory of Tree-Ring Research,The University of Arizona

Fire is a vital part of the Sierra forest ecosystem. Tree-ring analyses allows scientists to date the frequency and intensity of natural fires to better understand the role between climate cycles and fire frequency.



Sierran Treeline Dynamics in a Changing Climate
by Andrew G. Bunn
PhD Candidate
Department of Land Resources and Environmental Science
Montana State University

Hikers on the John Muir Trail might wonder at the expanses of wind blasted snags far above the present living forest. When did those trees live? How did they die? What does global warming mean for Sierran forests?


Sierra Nevada Bighorn Sheep: a Brief History
by John Wehausen, PhD
President, Sierra Nevada Bighorn Sheep Foundation

“Were granite to come to life, it would undoubtedly look like a bighorn sheep, so perfectly do they blend into that habitat” writes Dr. Wehausen of the endangered Sierra bighorn sheep. Numbering no more than 100 individuals only a few years ago, the scattered and isolated bands may be inching back from extinction.
Update 1/23/03: See Current Events.

Giardia Lamblia and Giardiasis
With Particular Attention to the Sierra Nevada

by Robert L. Rockwell, PhD

Is Giardia lamblia really the scourge of hikers in the Sierra backcountry? Test question: statistically, which would help more in prevention of giardiasis, a water filter or soap?
Article Updated: 5/15/02
(see "Cyst Survival" table).


Search for Rare Furbearers Leads CSERC Staff into Remote Corners of the Forest
by Andy Hatch
Biologist, Central Sierra Environmental Resource Center
John Buckley
Director, CSERC

Land management agencies need to know what's out there to better decide how to administer areas under their care. In a cooperative effort with the US Forest Service, the Central Sierra Environmental Resource Center (CSERC) operates photo stations in remote areas of the Stanislaus National Forest Service, searching for furry critters.

Monitoring snow from the beach in San Diego:
Automatic snow sensors in the Sierra

by J
essica Lundquist
Ph.D. Candidate
Hydroclimatology Group
Scripps Institution of Oceanography
University of California, San Diego

Frostbitten fingers may be a thing of the past for snow researchers: technology now makes it possible to monitor the Sierra snowpack from sunny San Diego—or anywhere else you can plug in a computer. Still, there is some shovel work on the road to this brave new world...



Tapping the Sierra Nevada Reservoir
by David Carle
Author of Drowning the Dream and Mono Lake Viewpoint

Do you know where your drinking water comes from? Follow the long journey of snow melting at 12,000 feet on the Sierra crest to your kitchen faucet. A huge, complex and expensive maze of dams and aqueducts work in the background so water is there for you at a twist of the handle. What are the costs to California's riparian habitat as a result?

Looking for the Past in the Higher Elevations of Kings Canyon National Park

Thomas L. Burge, Sequoia and Kings Canyon National Parks and
William Matthews, Giant Sequoia National Monument, North Zone Archaeologist, Sequoia National Forest

For thousands of years, Native Americans lived and traded in the harsh environment along the crest of the Sierra Nevada. Two archeologists describe their recent finds in Kings Canyon's alpine zone.

A Summer Spent Saving Frogs:
Applying Research to the Real World

by Ryan Peek
Biology Department, UC Davis

Based on recent research in the Sierra, restoring the habitat of the endangered mountain yellow-legged frog has become critical to their survival. Biologist Ryan Peek describes his summer spent fishin'.

Estimated Ages of Some Large Giant Sequoias:
General Sherman Keeps Getting Younger

Nathan L. Stephenson, Ph.D
U.S. Geological Survey, Western Ecological Research Center, Sequoia and Kings Canyon Field Station.

Although still venerable, recent work by Dr. Stephenson finds that Giant Sequoias aren't quite as old as previously thought. Alas.



Sherman Tree

Understanding Smog in the Sierra
by E. F. van Mantgem Meteorological station operator for Sequoia and Kings Canyon National Parks.

We think of our National Parks as the last islands of clean air and healthy ecosystems. Think again. The good news, though, is that the situation is reversible.




Searching for Slender Salamanders:
Adventures in Logrolling and Rock-Flipping
John Romansic
Zoology Department, Oregon State University.

Always the sign of a good job: getting paid to be a kid. Come with John as he searches for the elusive and cuddly Batrachoseps.

Slender Salamander
Mapping Sequoia & Kings Canyon's Vegetation:
From Muhlenbergia filiformis to Sequoiadendron giganteum

By Laura Pilewski Vegetation-mapping crew field botanist, Sequoia National Park

Follow a small band of botanists as they roam alpine peaks mapping and inventorying the flowers and plants of Sequoia and Kings Canyon National Parks.

Meadow Researcher

The Mountain Yellow-Legged Frog:
Can They be Saved?

Vance Vredenburg, Ph.D Museum of Vertebrate Zoology, Department of Integrative Biology, University of California, Berkeley

Recently proposed for endangered species listing, the Mountain Yellow-legged frog has been rapidly disappearing from high country lakes and streams. Researchers find a culprit.

Mountain Yellow legged frog

Vernal Pools - Ephemeral Oasis of the Foothills
by Alisa Durgarian, M.A., CSU Fresno

Nestled among the grasses and oaks of the foothills along the Sierra's west slope, vernal pools are an unheralded but vital part of that oak/grassland community. Biologist Alisa Durgarian explains the unique conditions that form their incredible diversity and where to see them.

Vernal Pool

A White Spring in the Mountains
by Christina Hargis, Ph.D

You may be mountain biking on dusty trails already or checking out conditions for wind surfing, but the mountains are still locked in snow. A former winter backcountry ranger in Yosemite listens to spring's arrival at 10,000 feet.

Winter Aspen


Grazing and Yosemite's Meadows:
Keeping the Balance
By Carol Blaney and Peggy Moore, research scientist, Yosemite National Park.

Can horses and mules, hikers and meadows peacefully co-exist? Research in Yosemite helps park managers come up with a plan.


Grazing Burro


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