When can you survey
for protected species?

Survey window

Summer survey season: May 15 – Aug 15

Method

Mist-net or acoustic (per current Guidelines)

Agency / protocol

USFWS — Range-Wide Indiana Bat & Northern Long-Eared Bat Survey Guidelines

Region

Eastern & midwestern US (species range)

Clearance / restriction window

Tree clearing generally restricted ~Apr 1 – Oct 15 in occupied summer habitat; confirm with the local Field Office

Summer presence/probable-absence window is May 15–Aug 15 for both mist-net and acoustic options. Tree-clearing dates and any post-season survey extensions are set by the local Field Office — confirm.

Survey window

Summer survey season: May 15 – Aug 15

Method

Mist-net or acoustic (per current Guidelines)

Agency / protocol

USFWS — Range-Wide Indiana Bat & NLEB Survey Guidelines

Region

Eastern, midwestern & much of the US (species range)

Clearance / restriction window

Pup season ~Jun 1 – Jul 31; reclassified to ENDANGERED 3/31/2023 — the former 4(d) tree-clearing exemptions no longer apply

Now federally ENDANGERED (effective Mar 31, 2023); the prior threatened-species 4(d) rule was removed, so the full ESA take prohibition applies. Survey window aligns with the Indiana bat guidelines.

Survey window

Summer survey season: May 15 – Aug 15 (aligned with IBat/NLEB)

Method

Mist-net or acoustic

Agency / protocol

USFWS — Range-Wide IBat/NLEB Survey Guidelines (tricolored-bat habitat guidance)

Region

Eastern & central US (species range)

PROPOSED endangered — verify the current listing status before relying on a determination. Species-specific consultation tools take effect only upon a final listing rule; the survey window is inferred from alignment with the IBat/NLEB guidelines.

Survey window

General nesting season ~Mar 15 – Sep 15 (varies by region/species)

Method

Pre-construction nest / clearance survey

Agency / protocol

USFWS — Migratory Bird Treaty Act — general nesting-season avoidance

Region

Nationwide

Clearance / restriction window

Avoid vegetation removal ~Mar 15 – Sep 15; if unavoidable, a nest-clearance survey is required

The Mar 15–Sep 15 window is a widely-used regional recommendation, NOT a single federal date. Actual nesting windows shift by latitude, elevation, and species — confirm with the local USFWS Migratory Bird office / state agency.

Survey window

Breeding season typically Jan/Feb – Aug (species-specific)

Method

Nest-occupancy survey; species-specific buffers

Agency / protocol

USFWS / state agencies — MBTA nesting-season avoidance; species-specific raptor buffers

Region

Nationwide

Many raptors initiate nesting earlier than passerines (some by Jan/Feb). Buffers and timing windows are species- and state-specific — confirm with the local USFWS office and state wildlife agency.

Survey window

Breeding-season nest occupancy & productivity surveys, ~Jan – Jul

Method

Aerial (helicopter preferred) + ground nest surveys; multiple visits

Agency / protocol

USFWS — USFWS Region 6 Eagle Nest Survey Protocol (wind) / eagle monitoring guidance

Region

Western US (and range)

Survey effort and exact timing depend on project type (wind vs. other) and region; failed nests are monitored at least through ~Apr 1. BGEPA disturbance/take permitting applies. Confirm scope with the local USFWS office.

Survey window

6 surveys, ≥1 week apart, Mar 15 – Jun 30

Method

Protocol pedestrian survey with taped call playback

Agency / protocol

USFWS — Coastal California Gnatcatcher Presence/Absence Survey Protocol (1997)

Region

Coastal southern California (coastal sage scrub)

Six presence/absence surveys at least one week apart between Mar 15 and Jun 30, in suitable coastal sage scrub. A USFWS recovery permit is required to conduct the protocol.

Survey window

≥8 surveys, ≥10 days apart, Apr 10 – Jul 31

Method

Protocol riparian pedestrian survey (dawn–~11:00)

Agency / protocol

USFWS — Survey Guidelines for the Least Bell's Vireo

Region

Southern California / Southwest riparian

At least 8 surveys spaced ≥10 days apart between Apr 10 and Jul 31 in suitable riparian habitat. Requires a USFWS recovery permit.

Survey window

5 surveys / 3 periods: May 15–31, Jun 1–24, Jun 25–Jul 17 (≥5 days apart)

Method

Call-playback protocol survey (around dawn)

Agency / protocol

USFWS / USGS — Survey Protocol for the Southwestern Willow Flycatcher (USGS TM 2A-10, 2010)

Region

Southwestern US riparian (AZ, NM, CA, NV, UT, CO, TX)

Five surveys across three periods (1 in P1, 2 in P2, 2 in P3), each ≥5 days apart. Requires a USFWS recovery permit.

Survey window

≥4 surveys across survey periods ~Jun 15 – Aug 15

Method

Call-playback protocol survey

Agency / protocol

USFWS / USGS — Survey Protocol for the Western DPS of the Yellow-Billed Cuckoo (2015)

Region

Western US riparian

Minimum four survey visits during the breeding-season survey periods (cuckoos arrive mid-June; nesting late June–late July). Confirm exact period boundaries against the current protocol. Requires a USFWS recovery permit.

Survey window

Survey season ~Apr 15 – Aug 5 (dawn audio-visual stations)

Method

Dawn audio-visual stations; multi-survey, multi-year

Agency / protocol

USFWS / Pacific Seabird Group — PSG Inland Survey Protocol (Evans Mack et al. 2003; revised 2024)

Region

Pacific NW coastal forests (CA, OR, WA)

Survey 'weeks' run ~Apr 15 through early Aug; surveys start before sunrise. A 2024 revised protocol exists — confirm the number of surveys/years and exact weeks against the current PSG/USFWS version.

Survey window

6 visits/year over 2 years; survey period ~Mar 1 – Aug 31

Method

Nighttime/daytime call-back surveys

Agency / protocol

USFWS — Protocol for Surveying Activities That May Impact Northern Spotted Owls (2012)

Region

Pacific NW (CA, OR, WA)

Two-year, six-visits-per-year protocol; initial visits late March/early April. Barred-owl presence complicates detection — coordinate survey design with USFWS.

Survey window

Breeding-season: 4 visits; first Feb 15 – Apr 15, then ≥3 visits ≥3 weeks apart

Method

Habitat assessment + focused breeding-season surveys

Agency / protocol

CDFW (California) — CDFW Staff Report on Burrowing Owl Mitigation (2012)

Region

California (and western US; check state protocol)

Clearance / restriction window

Breeding season Feb 1 – Aug 31 (75 m buffer); non-breeding Sep 1 – Jan 31 (50 m buffer)

California-specific (CDFW). Burrowing owl is a state Species of Special Concern and MBTA-protected, not federally listed. Other states use their own protocols — confirm locally.

Survey window

Lek counts: ≥3 counts/lek at ~weekly intervals, ~Mar 15 – Apr 30 (peak ~mid-Apr)

Method

Dawn lek counts

Agency / protocol

WAFWA / state wildlife agencies — Greater Sage-Grouse Range-Wide Population Monitoring Guidelines (WAFWA)

Region

Western US sagebrush (11 states)

Lek-count windows vary by state and elevation (generally Mar 15–Apr 30; peak male attendance ~mid-April). Not federally listed. Each state wildlife agency sets specific dates — confirm locally.

Survey window

Multiple day + night surveys; timing per USFWS guidance — varies, confirm with FO

Method

Day + nighttime visual-encounter surveys; site assessment first

Agency / protocol

USFWS — Revised Guidance on Site Assessment and Field Surveys for the California Red-Legged Frog (2005)

Region

California (and Baja); coastal & Central Valley

Protocol requires a site assessment, then a set number of day and night surveys (air temp ≥ ~50°F). Exact survey timing is set in coordination with the local USFWS Field Office — confirm. Requires a recovery permit.

Survey window

Conduct when tortoises most active: Apr–May or Sep–Oct

Method

Pedestrian transect surveys; clearance = 2 perpendicular passes

Agency / protocol

USFWS — Pre-Project & Clearance Survey Protocols for the Mojave Desert Tortoise (Rev. 2019)

Region

Mojave Desert (CA, NV, AZ, UT west of the Colorado River)

Surveys conducted during peak surface activity (spring Apr–May, fall Sep–Oct). Pre-project and clearance protocols are separate documents — use the correct one. An authorized handler is required for clearance.

Survey window

Warm/active season ~Apr – Oct (burrow surveys + scoping)

Method

Line-transect distance sampling or 100% burrow survey with burrow-camera scoping

Agency / protocol

USFWS / state agencies — Gopher Tortoise Survey Handbook (LTDS); USFWS Burrow Survey Protocol (2025)

Region

Southeastern US (FL, GA, AL, SC, MS, LA — western population listed)

The western population is federally threatened; the eastern population's status differs by state. Surveys are best done in warm active months (~Apr–Oct). State relocation permitting (e.g. FWC) has its own rules — confirm with the state agency.

Survey window

One wet-season + one dry-season survey within a 3-year period (follows pool hydrology)

Method

Wet-season aquatic dip-net sampling + dry-season cyst/soil sampling

Agency / protocol

USFWS — Survey Guidelines for the Listed Large Branchiopods (2017)

Region

California & southern Oregon vernal pools

A complete protocol survey is one wet-season + one dry-season survey (or two wet-season) within 3 years; wet-season timing depends on when pools inundate (typically winter–spring rains). Requires a USFWS recovery permit.

Survey window

Live-trapping during active season (~Jun – Sep)

Method

Sherman live-trapping, parallel transects

Agency / protocol

USFWS — Preble's Meadow Jumping Mouse Survey Guidelines (2004)

Region

Colorado Front Range & SE Wyoming riparian

Roughly 400–1,000 trap-nights (≈750 typical) during the active season when the mouse is above ground (it hibernates ~Oct–May). Exact trapping dates are set with the local USFWS office. Requires a recovery permit.