CALIFORNIA — Much like forests on land, kelp forests are a bonanza for biodiversity. …But kelp forests are fickle. They can boom and bust under the influence of marine heat waves, the El Niño–Southern Oscillation (ENSO), or storms. New research shows that forest fires in coastal watersheds also play a role. By comparing two data sets in an unexpected way, a team of researchers is exploring how forest fire size relates to kelp beds downstream. The team presented some of their findings at AGU’s Annual Meeting 2023 in San Francisco. …Preliminary research shows there’s an impact. The Woolsey Fire, for example, burned nearly 940 million square meters in November 2018, sending sediment into Malibu Creek. Before the fire, the spring 2018 kelp canopy covered 46,606 square meters near Malibu. The following spring, kelp covered only 9,543 square meters and has yet to recover to prefire levels.