Ephemeral streams condition index being developed using locally collected bioindicator data

Posted August 7, 2019
A ramp trap is deployed to capture terrestrial arthropods in a dry stream bed; the greenish chemical propylene glycol is used for preserving trapped organisms. SCCWRP and its partners are using data on stream arthropods and bryophytes to build tools for assessing the health of ephemeral streams.

SCCWRP and its partners have begun using biological indicator data collected from dry streams across Southern California to refine the design of a set of new tools for assessing ephemeral stream health.

Researchers are working to build a condition scoring tool for ephemeral streams modeled after the California Stream Condition Index, which was co-developed by SCCWRP for use in perennial streams. Ephemeral streams, or streams that flow only immediately after rain events, make up about 60% of all streams in Southern California.

Researchers are calibrating the index scoring tools with data collected for terrestrial arthropod, riparian arthropod and bryophyte communities. SCCWRP’s stream management partners have been collecting the bioindicator data from sites across Southern California over the past year.

More news related to: Bioassessment, Indices of Biotic Integrity