In California’s north coast, the Eel River winds its way through hills with shady slopes carpeted in lush ferns and towering redwoods and sunny ridges covered in brushy chaparral. The South Fork Eel River has been the site of extensive research by UC Berkeley professor Dr. Mary Power that has upended the traditional paradigm in ecology that trophic subsidies from forested watersheds shape river food webs, but subsidies from rivers are unimportant to forests.  During spring, floating mats of bright green algae grow on top of the water in the river. Aquatic insects like caddisflies and mayflies lay their eggs inside these mats, which provide nutritious food and protection from predators to their young when they hatch.