Statewide effort launched to update management guidance for benthic HABs

A statewide HABs monitoring workgroup has reconvened a subcommittee to be co-led by SCCWRP that will examine how to improve management options for protecting humans, dogs, and wildlife from toxin-producing benthic blooms, which tend to form mats along the bottom of water bodies.

The Benthic HABs Subcommittee of the California Cyanobacterial and Harmful Algal Bloom (CCHAB) Network, which reconvened in May, will refine and build on its original 2020 recommendations for how to monitor benthic HABs in California lakes, streams and other freshwater systems, as well as when and how to notify the public about blooms that may pose a health threat.

Unlike planktonic HABs that grow in the water column, benthic HABs have not been as extensively studied. In California, existing HAB toxin thresholds designed to protect humans and wildlife from exposure are for water-column HABs only. Meanwhile, because benthic HABs form as mats that attach to a range of bottom substrates, researchers believe humans and wildlife can be exposed to benthic HABs in less predictable ways (i.e., when pieces of the mat suddenly break off and become suspended in the water column or stranded on the shoreline).

The subcommittee plans to provide recommendations by the end of 2024. To join the subcommittee, contact Dr. Jayme Smith.