California Department of Fish and Wildlife

Sierra Nevada Bighorn Sheep In Yosemite

Mt. Gibbs
image of ewe
S160 - Ewe (kmz)

image of ram
S79 - Ram (kmz)
Click bighorn photos to view movement data
in Google Earth™

    Recent Events

  • 08/11/2016 All 5 ewes from Algiers observed with 4 yearlings recruited from last year. No lambs. It looks like these ewes were not bred this year.
  • 07/13/2016 S100 was observed with a lamb. She is 17 years old this year!. The main herd continues to grow.
  • 4/03/2015 CDFW added 5 ewes with high genetic diversity to the population. This is the second phase of a planned genetic rescue for this population. It would not have been possible without genetic research carried out by the Sierra Bighorn Foundation.
  • 07/02/2014 Six lambs observed for a second year. Another productive year for reproduction.
  • 11/20/2013 After making multiple excursions to Mt. Gibbs and the Kuna Crest often traveling through dense forest, unusual for Sierra bighorn, S172 has returned to her perch on the NW ridge of Mt. Dana where she could be visible from the road.
  • 8/8/2013 A total of 6 lambs have been born to the ewes of the Mt. Gibbs herd! This is the largest number of lambs observed in this population. Two of the lambs were born to ewes translocated here in March. The remaining 4 lambs were born to the native ewes.
  • 6/1/2013 Observations during May show a total of 19 bighorn: 10 adult ewes, 2 yearling ewes, 5 lambs, 2 adult rams. Not all ewes have been observed, so more lambs are possible.
  • 5/10/2013 S172, one of the newly translocated ewes, resides on the west side of Mt Dana and may be visible from the park entrance.

View seasonal maps as annotated video below
or see Flickr Album.

Alpine Summer near Parker Pass
Alpine summer near Parker Pass

Landsat - Satellite Images
The Landsat program offers the longest continuous global record of the Earth's surface by capturing images from space. United States Geologic Survey (USGS) has been using this system since the 1970's. Landsat imagery is taken approximately every two weeks. The image resolution is based on a 30m x 30m pixel size. The data are used for a wide variety of scientific investigations. Our program uses this information to describe snow cover. Images show snow (turquoise), bare ground (brown), and vegetation (green). Images were selected to show differences in habitat use patterns at various times during the year.
Animated map of translocated Mt Gibbs ewe movements after release