It may not feel like winter here in Southern California, but it is—and it’s almost over.

The end of winter means the beginning of spring surveys, and we’d like to take this opportunity to remind our clients that HELIX biologists have expertise in conducting the following spring surveys:

Quino checkerspot butterfly (dependent on weather and information collected from reference locations)

Although there is not a definitive start date for Quino surveys, we expect them to commence in the next two weeks. Beginning these surveys too late after the first Quino butterfly is observed in Southern California can be interpreted by the wildlife agencies as a false negative survey result.

Coastal California gnatcatcher (February 15 through August 31)

Surveys for this species can be completed year-round, but it is preferred to have them completed between February 15 and August 31. A minimum of three site visits (at least seven days apart) is required.

Rare plants (March/April and May/June)

Location of a project site and plant species that have a potential to occur in the area influence the timing of rare plant surveys. Typically, surveys are conducted in March and April. Sites that have potential to support late-blooming species may require a follow-up visit in May or June.

Burrowing owl (dependent upon location)

The winter survey period for burrowing owl has just ended, but the breeding season survey window is quickly approaching. The timing of spring owl surveys is dependent upon the location of the project, as western Riverside County follows a different survey protocol from the County of San Diego, which are each slightly different from the City of San Diego.

Arroyo toad (March 15 through July 1)

The survey period for arroyo toad runs from March 15 through July 1, and at least one site visit must be conducted during the months of April, May, and June. Surveys include daytime and nighttime components.

Least Bell’s vireo (April 10 through July 31)

Although the breeding season for this species officially begins on March 15, surveys cannot begin until April 10. As a reminder, eight surveys are required for this species, and surveys are expected to be 10 days apart, which means it takes over two months to conduct a complete survey.

Southwestern willow flycatcher (May 15 through July 17)

The survey window for this riparian-dependent species begins May 15. The survey protocol for this species was revised in 2010, and HELIX is up-to-speed on the new timing requirements for site visits.

Flat-tailed horned lizard (May through September)

Surveys for this species do not begin until the desert begins to warm up. Typically, surveys begin in late May or early June and can be conducted throughout the summer and early fall.

Schedule your survey

To schedule a spring survey, contact Tom Huffman, Biological Resources Division Manager, at TomH@helixepi.com or 619.462.1515 ext. 212.