Masthead: Kaweah Range

Nature Notes Archives: Critters

With Recovery Efforts Underway, Danger still exists for the frogs
by Peter Stekel

But now the bad news: while efforts to restore habitat in some lakes and streams is meeting with great success, a new disease is emerging which threatens those tenuous gains. The Chytrid fungus is wiping out populations throughout the Sierra and not much is known about how it's killing frogs.

The Mountain Yellow-legged Frog is Recovering in Sequoia and Kings Canyon National Parks
by Peter Stekel

Another in our series about efforts to reestablish critical habitat for the endangered Mountain Yellow-legged frog. Fish and disease continue to cause populations to crash throughout the Sierra, but efforts by Sequoia Kings aquatic biologist Danny Boiano and others give hope that this trend may be reversed.

Partners in Protection
Rachel Mazur Wildlife Biologist
Sequoia and Kings Canyon National Parks, California.

Many birds we think of as Sierra birds are actually just making a short stop on a long journey from South America to the Boreal forests of Alaska. An innovative program in Sequoia and Kings Canyon National Parks brings biologists from Central and South America north to contribute their knowledge of migratory species native to their homeland. After teaching and doing research in the Sierra, they take what they've learned home to further conservation efforts there.

Winter Wildlife in Tuolumne Meadows
Yosemite National Park

WINTER 2004/2005
Tracey Wiese and Bruce Carter
Tuolumne Winter Rangers, Yosemite National Park

Snow comes to Yosemite. The Tioga road closes and the high country becomes, once again, a true wilderness. Two rangers stay behind to patrol and note the variety and habits of critters who amble, run and fly about.

Using bat assemblages as a measure of ecosystem health
Leslie Chow
Wildlife Biologist, USGS, Yosemite Field Station, California
Elizabeth Pierson
Consulting Biologist, Berkeley, California
William E. Rainey
Associate Specialist, Department of Integrative Biology, University of California–Berkeley

Quick: how many species of bats in Yosemite? What's the second largest order of mammals in North America? Why do we know so little about them? Bats are a critical part of the Sierra ecosystem and, because they eat insects, also play a vital role in indicating the health of an ecosystem.

New Threat to Mountain Yellow-legged Frogs?
Lara Rachowicz PhD candidate
Department of Integrative Biology, University of California, Berkeley

Work continues to find the causes for the precipitous decline of the Sierra's Mountain Yellow-legged frog. Recent work suggests that, in addition to introduced non-native fish, a fungus may be also be a serious threat. Once more intrepid biologists wade through icy mountain lakes and streams in search of answers.

Preservation of a Healthy Black Bear Population in the Sierra Nevada Mountain Range through Interagency Cooperation
Tori Seher Yosemite National Park
Rachel Mazur Sequoia and Kings Canyon National Parks
Calder Reid Inyo National Forest
Adam Rich Stanislaus National Forest

Keeping one step ahead of bears intent on getting your food is a job now being carried out cooperatively by several Sierra land management agencies. Their goal is to get bears out foraging for roots and grubs, rather than your backpack or ice chest. The guiding principle of the Sierra Interagency Black Bear Group is to never underestimate an animal you can teach to ride a bicycle...

An Analysis of Human Pathogens Found in Horse/Mule Manure Along the John Muir Trail in Kings Canyon and Sequoia and Yosemite National Parks
Robert Wayne Derlet, MD James Reynolds Carlson, PhD

From the Emergency Department (Dr Derlet) and the Clinical Microbiology Laboratory (Dr Carlson), University of California, Davis, Medical Center, Sacramento, CA

Each year, thousands of horses and mules leave tons of manure along Sierra trails. What are the potential health risks to people drinking from Sierra streams? The answers are encouraging for both horse owners and backcountry hikers.

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.

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.

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.

Following the Frogs
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.

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.

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'.

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.

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.


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