FWS Focus

Overview

Characteristics
Overview

The mountain yellow-legged frog is a medium-sized frog and includes two distinct groups - the southern distinct population segment, which was listed as endangered in 2002, and the northern distinct population segment, which was listed as endangered in 2013. The two populations are geographically separated by a 140-mile stretch of unsuitable habitat.

The biggest threats to the species are:

  • Habitat destruction due to dams and water diversions, recreation, grazing, road construction and timber harvesting
  • Impacts of climate change climate change
    Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.

    Learn more about climate change
    , including wildfire and drought
  • Introduction of trout, bullfrogs and other non-native species that carry diseases and eat the frog

Scientific Name

Rana muscosa
Common Name
Mountain Yellow-legged Frog
Southern Mountain Yellow-legged Frog
FWS Category
Amphibians
Kingdom

Location in Taxonomic Tree

Genus

Identification Numbers

TSN:

Characteristics

Characteristic category

Physical Characteristics

Characteristics
Color & Pattern

Adult coloration is highly variable, with individuals tending to have a mix of brown and yellow coloring on their upper body. They can also be gray, red or greenish-brown. Most individuals have dark spots or splotches on their back and yellow or light-orange undersides and undersurface of the hind limbs.

Size & Shape

The mountain yellow-legged frog is a medium-sized frog, with males are slightly smaller than females.

Measurements
Length: 1.5 to 3.75 in (40 to 95 mm)

Characteristic category

Habitat

Characteristics
Habitat

The northern distinct population segment of mountain yellow-legged frogs live in Californiaโ€™s Sierra Nevada mountains in lakes, ponds, marshes, meadows and streams at elevations ranging from 4,500 to 12,000 feet (1,370 to 3,660 meters). The northern distinct population segment range extends from Fresno County, in the western Sierra Nevada, through portions of the Kern River drainage. The southern distinct population segment occupies the canyons of the Transverse Ranges in southern California.

Lake

A considerable inland body of standing water.

Mountain

A landmass that projects conspicuously above its surroundings and is higher than a hill.

River or Stream

A natural body of running water.

Wetland

Areas such as marshes or swamps that are covered often intermittently with shallow water or have soil saturated with moisture.

Characteristic category

Food

Characteristics
Food

Adults feed on terrestrial and aquatic insects and other amphibians. Adults forage for prey at the bottoms of lakes, ponds, and streams, as well as in shallow waters and onshore. Tadpoles feed on algae.

Characteristic category

Behavior

Characteristics
Behavior

Mountain yellow-legged frogs maximize body temperatures during the day by basking in the sun, moving between water and land and concentrating in the warmer shallows along the shoreline. 

Mountain yellow-legged frogs return to the same overwintering and summer habitats each year. Both adults and tadpoles overwinter for up to nine months in the bottoms of lakes, ponds and in-stream pools that are at least 5.6 feet deep (1.7 meters); however, overwinter survival may be greater in lakes that are at least 8.2 feet (2.5 meters) deep. Rock crevices, holes and ledges near water offer protection to overwintering frogs when water bodies freeze over completely.
 

Characteristic category

Life Cycle

Characteristics
Life Span

While the life span of mountain yellow-legged frogs is unknown, they are presumed to be long-lived amphibians.

Reproduction

Mountain yellow-legged frogs reach sexual maturity at 3 and 4 years of age. Adults emerge from overwintering sites immediately following snowmelt and move toward breeding sites. They will even move over ice to get there. The frogs breed in the shallows of ponds and lakes or in inlet streams. 

Mountain yellow-legged frogs deposit their eggs underwater in clusters, which they attach to rocks, gravel or vegetation. Eggs hatch between 16 to 21 days after fertilization.

Characteristic category

Similar Species

Characteristics
Similar Species

Geography

Characteristics
Range

The northern distinct population segment of this species live in Californiaโ€™s Sierra Nevada mountains in lakes, ponds, marshes, meadows and streams at elevations ranging from 4,500 to 12,000 feet (1,370 to 3,660 meters) and has a range that extends from Fresno County, in the western Sierra Nevada, through portions of the Kern River drainage. The southern distinct population segment lives in the canyons of the Transverse Ranges in southern California.

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Timeline

Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.

49 Items

Listing

Listing

Listing

Listing

Listing

Notice

Notice

Listing

Listing

Listing

Listing

Permit

Listing

Listing

NEPA - EIS

NEPA - EIS

Listing

Critical Habitat

Notice

Notice

NEPA - EA

Listing

Listing

Critical Habitat

Listing

Listing

Listing

Listing

Listing

Listing

Listing

Correction

Five Year Review

Listing

Listing

Listing

Listing

Listing

Listing

Five Year Review

Critical Habitat

Listing

Notice

Listing

Critical Habitat

Five Year Review

Recovery Plan

Five Year Review

Five Year Review

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Listing

Nov 21, 1991

Nov 21, 1991 Listing
ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species; 56 FR 58804 58836
  • Publication type: CNOR
Item 1

Listing

Nov 15, 1994

Nov 15, 1994 Listing
ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species.
  • Publication type: CNOR
Item 2

Listing

Jul 8, 1997

Jul 8, 1997 Listing (Substantial)
ETWP; 90-Day Finding for a Petition To List the Southern California Population of the Mountain Yelloโ€ฆ
  • Publication type: 90 day petition finding
Item 3

Listing

Dec 22, 1999

Dec 22, 1999 Listing (Endangered)
ETWP; Proposed Endangered Status for the Southern California Distinct Vertebrate Population Segmentโ€ฆ
  • Publication type: Proposed
Item 4

Listing

Dec 22, 1999

Dec 22, 1999 Listing (Warranted)
ETWP; Proposed Endangered Status for the Southern California Distinct Vertebrate Population Segmentโ€ฆ
  • Publication type: 12m petition finding
Item 5

Notice

Mar 20, 2000

Mar 20, 2000 Notice
Reopening of Comment Period on Proposed Endangered Status for the Southern California Distinct Populโ€ฆ
  • Publication type: Comment Period Reopening
Item 6

Notice

May 19, 2000

May 19, 2000 Notice
Reopening of Comment Period on Proposed Endangered Status for the Southern California Distinct Vertโ€ฆ
  • Publication type: Comment Period Reopening
Item 7

Listing

Oct 12, 2000

Oct 12, 2000 Listing (Substantial)
90-Day Finding on a Petition To List the Mountain Yellow-legged Frog as Endangered
  • Publication type: 90 day petition finding
Item 8

Listing

Oct 30, 2001

Oct 30, 2001 Listing
ETWP; Review of Plant and Animal Species That Are Candidates or Proposed for Listing as Endangered oโ€ฆ
  • Publication type: CNOR
Item 9

Listing

Jun 13, 2002

Jun 13, 2002 Listing
Endangered and Threatened Wildlife and Plants; Review of Species That Are Candidates or Proposed forโ€ฆ
  • Publication type: CNOR
Item 10

Listing

Jul 2, 2002

Jul 2, 2002 Listing (Endangered)
Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for the Southern Cโ€ฆ
  • Publication type: Final
Item 11

Permit

Nov 15, 2002

Nov 15, 2002 Permit
Notice of Availability of a Draft Environmental Impact Statement/Environmental Impact Report and Recโ€ฆ
  • Publication type: Application Received
Item 12

Listing

Jan 16, 2003

Jan 16, 2003 Listing (Warranted But Precluded)
Endangered and Threatened Wildlife and Plants; 12-Month Finding for a Petition To List the Sierra Neโ€ฆ
  • Publication type: 12m petition finding
Item 13

Listing

May 4, 2004

May 4, 2004 Listing
Review of Species That Are Candidates or Proposed for Listing as Endangered or Threatened; Annual Noโ€ฆ
  • Publication type: CNOR
Item 14

NEPA - EIS

Jan 10, 2005

Jan 10, 2005 NEPA - EIS
Notice of Intent to Scope for the Preparation of an Environmental Impact Statement for the Proposedโ€ฆ
  • Publication type: Draft
Item 15

NEPA - EIS

Mar 7, 2005

Mar 7, 2005 NEPA - EIS
Preparation of an Environmental Impact Statement for Issuance of an Incidental Take Permit Associateโ€ฆ
  • Publication type: Draft
Item 16

Listing

May 11, 2005

May 11, 2005 Listing
Endangered and Threatened Wildlife and Plants; Review of Native Species That Are Candidates or Proโ€ฆ
  • Publication type: CNOR
Item 17

Critical Habitat

Sep 1, 2005

Sep 1, 2005 Critical Habitat
Endangered and Threatened Wildlife and Plants; Proposed Designation of Critical Habitat for the Soutโ€ฆ
  • Publication type: Proposed
Item 18

Notice

Jul 3, 2006

Jul 3, 2006 Notice
Proposed Designation of Critical Habitat for the Southern California Distinct Vertebrate Populationโ€ฆ
  • Publication type: Public Hearing
Item 19

Notice

Jul 3, 2006

Jul 3, 2006 Notice
Proposed Designation of Critical Habitat for the Southern California Distinct Vertebrate Populationโ€ฆ
  • Publication type: Comment Period Reopening
Item 20

NEPA - EA

Jul 3, 2006

Jul 3, 2006 NEPA - EA
Proposed Designation of Critical Habitat for the Southern California Distinct Vertebrate Populationโ€ฆ
  • Publication type: Draft
Item 21

Listing

Sep 12, 2006

Sep 12, 2006 Listing
Review of Native Species That Are Candidates or Proposed for Listing as Endangered or Threatened; Anโ€ฆ
  • Publication type: CNOR
Item 22

Listing

Sep 12, 2006

Sep 12, 2006 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates or Proposed for Listing as Endangered or Threatened; Anโ€ฆ
  • Publication type: 12m petition finding
Item 23

Critical Habitat

Sep 14, 2006

Sep 14, 2006 Critical Habitat
Designation of Critical Habitat for the Southern California Distinct Population Segment of the Mountโ€ฆ
  • Publication type: Final
Item 24

Listing

Jun 25, 2007

Jun 25, 2007 Listing (Warranted But Precluded)
12-Month Finding on a Petition To List the Sierra Nevada Distinct Population Segment of the Mountainโ€ฆ
  • Publication type: 12m petition finding
Item 25

Listing

Dec 6, 2007

Dec 6, 2007 Listing
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticโ€ฆ
  • Publication type: CNOR
Item 26

Listing

Dec 6, 2007

Dec 6, 2007 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticโ€ฆ
  • Publication type: 12m petition finding
Item 27

Listing

Dec 10, 2008

Dec 10, 2008 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticโ€ฆ
  • Publication type: 12m petition finding
Item 28

Listing

Dec 10, 2008

Dec 10, 2008 Listing
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticโ€ฆ
  • Publication type: CNOR
Item 29

Listing

Nov 9, 2009

Nov 9, 2009 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: 12m petition finding
Item 30

Listing

Nov 9, 2009

Nov 9, 2009 Listing
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: CNOR
Item 31

Correction

Feb 24, 2010

Feb 24, 2010 Correction
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: Notice
Item 32

Five Year Review

May 21, 2010

May 21, 2010 Five Year Review (Information Solicitation)
Initiation of 5-Year Reviews of 34 Species in California and Nevada; Availability of 96 Completed 5-โ€ฆ
  • Publication type: Notice
Item 33

Listing

Nov 10, 2010

Nov 10, 2010 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: 12m petition finding
Item 34

Listing

Nov 10, 2010

Nov 10, 2010 Listing
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: CNOR
Item 35

Listing

Oct 26, 2011

Oct 26, 2011 Listing
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: CNOR
Item 36

Listing

Oct 26, 2011

Oct 26, 2011 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: 12m petition finding
Item 37

Listing

Nov 21, 2012

Nov 21, 2012 Listing
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: CNOR
Item 38

Listing

Nov 21, 2012

Nov 21, 2012 Listing (Warranted But Precluded: Resubmitted)
Review of Native Species That Are Candidates for Listing as Endangered or Threatened; Annual Noticeโ€ฆ
  • Publication type: 12m petition finding
Item 39

Five Year Review

Apr 1, 2013

Apr 1, 2013 Five Year Review (Completion)
Initiation of 5-Year Reviews of 56 Species in California and Nevada; request for information
  • Publication type: Notice
Item 40

Critical Habitat

Apr 25, 2013

Apr 25, 2013 Critical Habitat
Designation of Critical Habitat for the Sierra Nevada Yellow-Legged Frog, the Northern Distinct Popuโ€ฆ
  • Publication type: Proposed
Item 41

Listing

Apr 25, 2013

Apr 25, 2013 Listing (Endangered)
Endangered Status for the Sierra Nevada Yellow-Legged Frog and the Northern Distinct Population Segmโ€ฆ
  • Publication type: Proposed
Item 42

Notice

Jan 10, 2014

Jan 10, 2014 Notice
Endangered Status for the Sierra Nevada Yellow-Legged Frog and the Northern Distinct Population Segmโ€ฆ
  • Publication type: Comment Period Reopening
Item 43

Listing

Apr 29, 2014

Apr 29, 2014 Listing (Endangered)
Endangered Species Status for Sierra Nevada Yellow-Legged Frog and Northern Distinct Population Segmโ€ฆ
  • Publication type: Final
Item 44

Critical Habitat

Aug 26, 2016

Aug 26, 2016 Critical Habitat
Designation of Critical Habitat for the Sierra Nevada Yellow-Legged Frog, the Northern DPS of the Moโ€ฆ
  • Publication type: Final
Item 45

Five Year Review

Jun 18, 2018

Jun 18, 2018 Five Year Review (Information Solicitation)
Initiation of 5-Year Status Reviews of 50 Species in California, Nevada, and the Klamath Basin of Orโ€ฆ
  • Publication type: Notice
Item 46

Recovery Plan

Jul 19, 2018

Jul 19, 2018 Recovery Plan (Document Availability (non-FR))
Notice of Availability: Draft Recovery Plan for the Southern California Distinct Population Segmentโ€ฆ
  • Publication type: Draft
Item 47

Five Year Review

Feb 10, 2020

Feb 10, 2020 Five Year Review (Information Solicitation)
Initiation of 5-Year Status Reviews of 66 Species in California and Nevada; request for information
  • Publication type: Notice
Item 48

Five Year Review

Aug 17, 2023

Aug 17, 2023 Five Year Review (Information Solicitation)
Endangered and Threatened Wildlife and Plants; Initiation of 5-Year Status Reviews of 47 Species inโ€ฆ
  • Publication type: Notice
Item 49