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!

Our more than 60 full-time biologists deliver thorough, defensible biological assessments and reports using our understanding of federal and state regulations and policies, diverse species and habitats, and the latest survey protocols and technology. We provide a depth of biological expertise, geographic breadth, regulatory contacts, and experience to meet your California species survey needs on any project.

Cool Timeline

2022
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

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

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

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
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

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
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)

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

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

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

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

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

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
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

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

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

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

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

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

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

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)

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

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

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

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

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
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

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

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

Curious how our passionate experts can help you Du More? Get in touch!