Ever since my Dad let me drive the car down Long Beach dodging washed up masses of kelp with my feet barely reaching the pedals – something you could do in the 1970s – I’ve been drawn to the crashing of waves on the long stretches of sandy beach, the churn of the ocean as it beats relentlessly on the rocky reefs. Ever since, I have loved exploring the nooks and crannies of the coast, while keeping an eye over my shoulder, wondering what the open ocean might bring next. Little did I know in those early days that, decades later, my work would bring me back here. Cruising rocky reefs instead of beaches, in a small boat instead of a car, working to understand the productivity and value of this rugged, coastal ecosystem.

Coastal kelp forests are one of the most productive ecosystems on the planet, with giant kelp (Macrocystis pyrifera) growing as much as a metre a day during peak growing seasons. These towering plants reach the surface from depths of up to 30m, creating expansive marine forests that serve as important habitat for many marine species, as well as providing a range of services for coastal communities.

However, these kelp forests do not always adorn the rocky reefs on which they depend for their holdfasts. In some places, they have been absent for over a century due to relentless grazing by sea urchins, their greatest predator. The dominance of sea urchins and other large invertebrates in many coastal systems is a consequence of the marine fur trade. This global endeavour killed over one million sea otters for their pelts, driving the species to near extinction across their entire North Pacific range. Only a few thousand animals were left in small remnant populations after the species was protected by international treaty in 1911.