January Showers Bring March Flowers

By Ann Johnston, Principal and Team Leader of Resource Management in Psomas’ Environmental Consulting Group

January Showers Bring March Flowers

This is not quite the same old English proverb you recognize, but given the early winter rains and the forecast for additional rain over the next several weeks, spring 2017 is predicted to be an optimal time to conduct focused special-status plant surveys. Now is the time to also plan your focused surveys for special status wildlife species. Planning ahead helps avoid costly project delays. Many of these species have narrow time frames or “windows” in which surveys can be conducted due to agency protocols or the species’ life cycle. These surveys are often required for environmental documentation for the California Environmental Quality Act [CEQA]/National Environmental Policy Act [NEPA] and/or State/Federal Endangered Species Act [ESA] compliance.

Avoid having your surveys rejected. Hiring qualified biologists with the technical background, experience, and survey permits ensures compliance with resource agency requirements. Some of the most commonly required focused surveys are listed below.

Cactus Wren

Nesting Birds

Resource agency permits and CEQA/NEPA documentation often have specific mitigation measures to conduct pre-construction nesting bird surveys, which also provide protection pursuant to the federal Migratory Bird Treaty Act and California law. If you already have your project approvals, check your permits and schedule the needed pre-construction surveys as soon as possible.

Nesting bird surveys: generally March – August

Intermediate Mariposa Lily

Special Status Plants

Due to the increased rainfall this winter, and the expectation of more rain in the coming weeks, spring 2017 is anticipated to generate good plant germination and growth, which corresponds to good survey conditions. These surveys are typically conducted during a plant’s blooming period. Our botanists monitor known populations of the target species to determine the appropriate survey window to generate the most reliable survey results.

Focused plant surveys: generally March – July

Spring Surveys: Desert Species

Mohave Ground Squirrel

Desert Species

Some of the most narrow and labor-intensive survey protocols are for species that occupy the desert regions. This is due to extreme temperatures that can limit the time they are observable. Examples include:

Desert tortoise: must be conducted during the species’ most active periods, April – May or September – October
Mohave ground squirrel: multiple visits conducted between March 15 – July 15, depending on weather
San Joaquin kit fox: surveys begin May – September, but must be completed by November 1

Arroyo Toad


Special status amphibians require water, especially during the beginning stages of their life cycles. Each has specific survey requirements to determine their presence or absence. Examples include:

Arroyo toad: six surveys conducted March 15 – July 1
California red-legged frog: eight surveys conducted over six weeks between January 1 and September 30

Spring Surveys: Burrowing Owls

Burrowing Owl

Burrowing Owls

Burrowing owls tend to occur in grasslands and areas with low vegetation. Projects occurring in suitable habitat within the species’ range will require surveys, including a habitat assessment and four focused surveys.

Burrowing owls: breeding and non-breeding (wintering) season surveys are conducted year round.


Spring Surveys: Bats

Pallid Bats


Bat surveys are being requested more by State and federal agencies, including Caltrans. Examples include:

Habitat assessments: any time of the year
Focused nighttime surveys (acoustic):
* Select species of bats, including many migrants: early spring or late fall
* Bat maternity colonies: summer

California Gnatcatcher

Coastal California Gnatcatcher and Riparian Birds

While coastal California gnatcatcher surveys can be conducted year round, there are time and cost savings if surveys are conducted during the breeding season (March 15 – June 30).

The least Bell’s vireo, southwestern willow flycatcher, and western yellow-billed cuckoo are federally and State-listed threatened and/or endangered bird species that occur in riparian habitat. Their survey windows include:

Least Bell’s vireo: April 10 – July 31
Southwestern willow flycatcher: May 15 – July 17
Western yellow-billed cuckoo: June 15 – August 15

Now is the time to schedule your focused spring surveys.

Please contact either Ann Johnston or Marc Blain at 714.751.7373 with questions regarding the potential need for focused spring surveys for your project.

Learn more about Psomas’ Environmental Consulting.


Tagged with: , ,  

Leave a Reply

Your email address will not be published. Required fields are marked *