An eDNA Platform for Community-Powered LA River Restoration

What this was about

Ryan Martin describes how community groups, land managers and Indigenous groups monitoring removal of concrete from the heavily channelized Los Angeles River used eDNA metabarcoding (12 sites, seven months, six markers) and the eDNA Explorer platform. The platform handles sequencing processing, taxonomic assignment, GBIF comparisons, seasonal analyses and random-forest community models using about 400 Google Earth Engine variables, showing concrete as a strong predictor of community composition. The work, funded by Metabolic Studio with CALeDNA at UC Santa Cruz, founded eDNA Explorer and now supports ongoing restoration monitoring.

Why it matters. It shows how packaging eDNA workflows makes advanced biodiversity monitoring accessible to communities and restoration projects.

In the room

• About 95% of the LA River is channelized in concrete following 1930s flood control.
• Protect Our River (from 2019) brought together community groups, land managers and Indigenous groups.
• eDNA sampling at 12 sites over seven months with six markers across the tree of life.
• eDNA detected taxa not in GBIF for the area, e.g. freshwater jellyfish in about a third of samples.
• Seasonal patterns shown from CO1 marker data.
• Random forest models on ~400 Earth Engine variables found concrete a strong predictor across most markers.
• Results support restoration monitoring, a proposed pathogen baseline for the 2028 Olympics, and Indigenous revitalisation efforts; GBIF uploads have just started.

Notable moments