“Perfect Storm” Decimates Northern California Kelp Forests

photo by A. Maguire
kelp cover maps
Comparison of kelp cover at four important abalone fishery sites in 2008 and 2014. Green indicates kelp canopy observed. Maps created from data collected during CDFW aerial surveys. (Data: M. Fredle)

Northern California kelp forests have been reduced to an all-time low due to a “perfect storm” of large-scale ecological impacts. The California Department of Fish and Wildlife (CDFW) marine invertebrate management team has conducted annual ecosystem surveys of kelp forests in Sonoma and Mendocino counties since the late 1990s, and recent observations have caused concern about the state of the kelp forests. The severe reduction in kelp has already impacted the recreational red abalone fishery and commercial red urchin fishery, two economically important fisheries in northern California.

Abalone and Urchins Starving

Bull kelp (Nereocystis luetkeana), usually common on the northern California coast, has declined dramatically since 2014. Kelp forests are now 93 percent smaller compared to previous years, creating starvation conditions for herbivores. Continue reading ““Perfect Storm” Decimates Northern California Kelp Forests”