California Species Survey Timeline

This timeline is a general guideline for California species survey requirements for selected plant and animal species. Some federally listed species require a 15-day notice to USFWS prior to commencing surveys within the survey periods identified on this calendar; some require USFWS approval to begin. For current regulations regarding complete survey requirements, get in touch!

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All Species

2022
January 1

Fairy shrimp

Fairy shrimp

Branchinecta spp. and Streptocephalus woottoni

Habitat: Vernal pools/playas

Survey Window: Year-round

• Conduct one wet-season (winter/spring) and one dry-season survey (summer/fall, soil collection)
• Wet season survey: sample all 3-centimeter-deep pools that last 24 hours

January 1

Stephens’ kangaroo rat

Stephens’ kangaroo rat

Dipodomys stephensi

Habitat: Grasslands, open; elevation 180–4,100 feet

Survey Window: Year-round
• Minimum five consecutive trapping nights, unless captured sooner
• Trapping may not be conducted if nightly low temperatures are forecast to fall below 50ºF

January 1

San Bernardino kangaroo rat

San Bernardino kangaroo rat

Dipodomys merriami parvus

Habitat: Alluvial, scrub; elevation below 4,500 feet

Survey Window: Year-round
• Minimum five consecutive trapping nights, unless captured sooner
• Trapping may not be conducted if nightly low temperatures are forecast to fall below 50ºF

January 1

California red-legged frog

California red-legged frog

Rana draytonii

Habitat: Riparian, pond; elevation up to 4,500 feet

Survey Window: Jan 1-Sep 30

• At least one survey before August 15 with a minimum 6-week survey period

• Jan 1-Jun 30: 2 diurnal surveys and 4 nocturnal surveys

• Jul 1-Sep 30: 1 diurnal survey and 1 nocturnal survey
• One-week interval between surveys

January 1

Swainson’s hawk

Swainson’s hawk

Buteo swainsoni

Habitat: Woodlands, grasslands, scrub, agricultural land

Antelope Valley (Los Angeles and Kern counties)

Conduct surveys within 5 miles radius

At minimum, complete 2 survey periods before project initiation; complete Periods 2, 3, and 4 before environmental review

Survey potential nesting trees within a 5-mile radius for presence of nests

  • Period 1: (optional; pre-arrival) Jan–Mar 31; all day; 1 pass
  • Period 2: (arrival/nest building) Apr 1–Apr 30; all day; 3 passes
  • Period 3: (as needed for monitoring known nest sites; egg laying/incubation) May 1–May 30; daylight hours
  • Period 4: (fledgling) Jun 1–Jul 15; sunrise to 1200 and 1600 to sunset; 3 passes
Central Valley

Conduct surveys within a half-mile radius

At minimum, complete 2 survey periods before project initiation. Periods 2, 3, and 5 always recommended

  • Period 1: (recommended/optional) Jan–Mar 20; all day; 1 pass
  • Period 2: (arrival/courtship/territorial) Mar 21–Apr 5; sunrise–10:00/16:00–sunset; 3 passes
  • Period 3: (nest building/copulation/territorial/courtship) Apr 5–Apr 20; sunrise–12:00 and 16:30–sunset; 3 passes
  • Period 4: (only for monitoring known nest sites) Apr 21–Jun 10
  • Period 5: (post-fledgling) Jun 11–Jul 30; sunrise–12:00 and 16:00–sunset; 3 passes
February 1

Nesting Birds (General)

Nesting Birds (General)

Habitat: All habitats

Survey Window: Feb–Aug

  • Occurs if there is a potential for nesting birds
  • Number and frequency of visits varies by project
February 14

Quino checkerspot butterfly

Quino checkerspot butterfly

Euphydryas editha quino

Habitat: Open; elevation below 5,000 feet
Survey Window: Third week of February–second Saturday in May
• If detected, minimum 5 diurnal surveys; otherwise, at least 13 surveys
• Minimum 4-day interval between surveys
• Weather conditions may alter survey season
• Survey period and number may be altered with USFWS coordination (usually related to elevation)

February 15

Ridgway’s rail

Ridgway’s rail

Rallus obsoletus levipes

Habitat: Salt marsh, coastal emergent wetlands

Survey Window: Feb 15–Apr 30
• Six diurnal surveys, at least one at dusk and one at dawn
• Minimum 7-day interval between surveys

February 15

Western burrowing owl

Western burrowing owl

Athene cunicularia hypugaea

Habitat: Grasslands, open; elevation up to 5,300 feet

Survey Window: Feb 15–Jul 15
• Four crepuscular (dawn and dusk) surveys, 500-foot buffer as legally able, 7- to 10-meter transects
• Feb 15–Apr 15: One survey
• Apr 16–Jul 15: Three surveys with 3-week interval between surveys
• Pre-construction surveys required in suitable habitat within 30 days of ground disturbing activities

February 15

Belding’s savannah sparrow

Belding’s savannah sparrow

Passerculus sandwichensis beldingi

Habitat: Salt marsh

Survey Window: Feb 15–Apr 30
• Five diurnal surveys
• General season, weather conditions may alter survey season

February 15

Brown-headed cowbird

Brown-headed cowbird

Molothrus ater

Habitat: Woodlands, grasslands

Survey Window: Feb 15–Aug 30

• Trap throughout breeding season or as required by permit

• Generally, maintain up to three males and two wing-clipped females in trap

• Check traps daily to release non-target captures

March 1

Mohave ground squirrel

Mohave ground squirrel

Xerospermophilus mohavensis

Habitat: Desert scrub

Survey Window: Mar 1–Jul 15

Mar 1–Apr 15: Diurnal visual surveys

Mar 1–Apr 30: First 5-day trapping period

May 1–May 30: Second 5-day trapping period

Jun 1–Jul 15: Third 5-day trapping period

March 1

White-tailed kite

White-tailed kite

Elanus leucurus

Habitat: Grassland, agricultural, wetland, riparian, woodlands, savannah

Survey Window: Mar 1–Jun 15

  • Surveys follow California Coastal Commission protocol
  • Five morning surveys spaced at least one week apart
March 1

California tiger salamander

California tiger salamander

Ambystoma californiense

Habitat: Grasslands, vernal pools/playas

Survey Window: Mar 1-May 30; October 1-March 15
• Larval survey: Three surveys, one each in March, April, and May; 10-day interval between surveys
• Drift fence survey: October 15-March 15; surround ponds and additional fences equaling 90% of site perimeter; traps open at night during rainy or humid weather; 20 trap nights per location

March 15

Coastal California gnatcatcher

Coastal California gnatcatcher

Polioptila californica californica

Habitat: Scrub; elevation up to 2,000 feet

Breeding Survey Window: Mar 15-Jun 30

Non-Breeding Survey Window: Jul 1-March 14
• Within Natural Community Conservation Plan (NCCP) area: Three diurnal surveys with seven-day interval between surveys, year round
• Outside NCCP area: Mar 15–Jun 30: Six diurnal surveys with seven-day interval between surveys; Jul 1–Mar 14: Nine diurnal surveys with 14-day interval between surveys

March 15

Arroyo toad

Arroyo toad

Anaxyrus californicus

Habitat: Alluvial, scrub, riparian; elevation 1,000–4,500 feet

Survey Window: Mar 15–Jun 30

• At least one survey in April, May, and June
• Six paired nocturnal/diurnal surveys
• Minimum 7-day interval between surveys
• Surveys should not occur during or near full moon period

March 20

Mojave desert tortoise

Mojave desert tortoise

Gopherus agassizii

Habitat: Desert; elevation up to 5,000 feet

Survey Window: Mar–May 30; Sep 1–Oct 31 (Presence/Absence)
• One diurnal survey
• Project area and zone of influence is surveyed
• General season, weather conditions may alter survey season, per USFWS

April 1

Pacific pocket mouse

Pacific pocket mouse

Perognathus longimembris pacificus

Habitat: Grasslands, scrub, generally within 5 miles of coast

Survey Window: Apr 1–Sep 30
• Minimum five consecutive trapping nights, unless captured sooner
• Trapping may not be conducted if nightly low temperatures are forecast to fall below 50ºF

April 1

Thorne’s hairstreak butterfly

Thorne’s hairstreak butterfly

Callophrys thornei

Habitat: Cypress woodlands, chaparral; elevation 1,000–4,500 feet

Survey Window: Determined by emergence of species (approx. Apr 1–May 30
• Five weekly diurnal surveys

April 10

Least Bell’s vireo

Least Bell’s vireo

Vireo bellii pusillus

Habitat: Riparian; elevation below 4,000 feet

Survey Window: Apr 10–Jul 31
• Eight diurnal surveys
• Ten-day interval between surveys

April 15

Laguna Mountains skipper

Laguna Mountains skipper

Pyrgus ruralis lagunae

Habitat: Meadow; elevation 3,900–6,000 feet

Survey Window: Apr 15–Jul 31
• Two-year survey
• Weekly visits during entire season (19 surveys)

April 15

Western pond turtle

Western pond turtle

Actinemys marmorata

Habitat: Riparian, Pond; elevation below 6,000 feet

Survey Window: Apr 15–Sep 15
• No official survey method
• Five surveys recommended
• General season, weather conditions may alter survey season

May 1

Southwestern willow flycatcher

Southwestern willow flycatcher

Empidonax traillii extimus

Habitat: Riparian; elevation below 8,500 feet

Survey Window: May 1–Jul 31

• May: 1 diurnal survey; June: 2 diurnal surveys; July: 2 diurnal surveys

• Five-day minimum interval between any survey

• When surveying for both southwestern willow flycatcher and least Bell’s vireo, separate surveys must occur with flycatcher surveys performed first

May 1

Mountain yellow-legged frog

Mountain yellow-legged frog

Rana muscosa

Habitat: Riparian, pond; elevation 1,000–6,900 feet

Survey Window: May 1–Aug 30
• Three diurnal surveys
• Each survey separated by minimum 7 days

May 16

Hermes copper butterfly

Hermes copper butterfly

Lycaena hermes

Habitat: Woodlands, chaparral, coastal sage scrub; elevation 200–4,000 feet

Survey Window: third full week of May–first full week of July
• Four diurnal surveys; 8- to 14-day intervals
• Look for spiny redberry associated with buckwheat that occurs within 15 feet

• Learn more about critical habitat and ESA considerations

May 23

Western snowy plover

Western snowy plover

Charadrius nivosus nivosus

Habitat: Coastal beaches, shores of inland ponds/lakes

Breeding Season Survey Window: Late May–Mid June

Winter Season Survey Window: Dec 1–Jan 31

  • One survey pass with one surveyor for beaches <50 meters wide; two surveyors for beaches
    >50 meters wide
June 1

Harbison’s dun skipper

Harbison’s dun skipper

Euphyes vestris harbisoni

Habitat: Oak woodlands, wooded riparian

Survey Window: Determined by emergence of species (approx. late spring–early summer
• Five weekly diurnal surveys
• Alternatively, year-round, perform single-pass survey of patches of Carex spissa for evidence of grazing or characteristic tent structures

July 1

Delhi sands flower-loving fly

Delhi sands flower-loving fly

Rhaphiomidas terminatus abdominalis

Habitat: Delhi sand and dune substrates in western Riverside and
San Bernardino Counties

Survey Window: Jul 1–Sep 20
• Two-year survey
• Two visits per week (1618 visits)
• Survey season may be altered by USFWS

December 1

Western spadefoot toad

Western spadefoot toad

Spea hammondii

Habitat: Grasslands, vernal pools/playas; elevation up to 4,500 feet

Survey Window: Dec 1–Mar 31
• Three nocturnal surveys, each survey conducted after/during rain event of 0.25 inches or greater
• Approximate 10-meter transects
• General season, weather conditions may alter survey season

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