P.O. Box 577
Yosemite, CA 95389
www.nps.gov/yose/news

209 372-0529 phone
209 372-0371 fax

June 23, 2003
For Immediate Release

Yosemite National Park, Museum of Vertebrate Zoology to Resurvey Grinnell Transects

During the years of 1914-1920, Joseph Grinnell, Director of the Museum of Vertebrate Zoology (MVZ), University of California at Berkeley, and Tracy Storer, Curator and Field Naturalist for MVZ led a series of "transect" studies through the central Sierra Nevada, including Yosemite National Park, to survey mammals, birds, reptiles, and amphibians.

A transect is a narrow, rectangular area designed to encompass a broad range of habitats, in this case, from the San Joaquin Valley, through the Sierra Nevada, and to the Great Basin near Mono Lake.

To date, these surveys stand as the most extensive study of vertebrate life in Yosemite, but are now nearly a century old.

Biologists from Yosemite National Park and U.S. Geological Survey approached MVZ regarding new biotic surveys of the park as part of the National Park Service's Inventory and Monitoring Initiative. This initiative is designed to increase the amount of knowledge national park units have on natural resources, and so better equip these units to protect their resources. In this effort, Yosemite is part of the Sierra Nevada Network, which also includes Devil's Postpile National Monument and Sequoia and Kings Canyon National Parks.

In the Biological Inventory Plan completed by the network in 2001, gaps in the park's information on the presence or absence of certain species were identified, and a plan for filling these gaps was developed.

By chance, the park's need for these data coincided with an effort by the MVZ to commemorate their centennial with a repeat of the "Grinnell Transects" which covered nearly all habitat types in California. Such an effort will provide valuable information about how the diversity of wildlife species has changed since the transect surveys were conducted in the early 20th century.

The National Park Service and MVZ will be working together over the next two years to resurvey the same transect that Grinnell and Storer covered in Yosemite over 80 years ago.

The resurvey will provide updated information on the animal species present and the condition of their habitats. That will be valuable in assessing past human-caused changes and anticipating future ones.

-NPS-