Updated November 12, 2024
BY TULLAH MCCOLL
Sun peeks through the kelp bed canopies of the cool Pacific Ocean edge, where a complex web of species can not only survive but thrive off of the nutrient-dense environment. Monterey Bay and the whole of Northern California’s coast is known for its lush covering of ecologically rich kelp forests.
“It is three-dimensional,” says Steve Lonhart, a research ecologist for Monterey Bay National Marine Sanctuary, an organization under the National Oceanic and Atmospheric Administration. “Instead of birds flying around a forest, if you went diving you would see fish swimming around you.”
Divers get to experience the underwater world of a kelp forest, an essential aspect of our environment. (courtesy of STEVE I. LONHART, NOAA MBNMS)
Lonhart emphasizes the indefinable and miraculous experience of seeing underwater forests during a diving expedition.
“Kelp is one of the richest, most biodiverse ecosystems that we have. It’s similar to the rainforests in the Amazon,” explains Chad King, another research ecologist for MBNMS. “[Kelp’s] an apartment building, from the floor to the surface of the ocean, providing a habitat and food for all those animals.”
Yet events that began a little over 10 years ago have led to an immense decline in the population of kelp along the California coast. An unknown cause set off a decimation of the sunflower star, a specific kind of sea star that preys primarily on sea urchins, being referred to as the Sea Star Wasting Syndrome.
Although they may be correlated, it is not confirmed if the elimination of sunflower stars is the direct cause of the explosion of urchin populations that followed. It is known that the Wasting Syndrome wasn’t the only factor driving the expansion of urchins. Intense heat wave events known as “The Blob” and an El Niño event that followed from 2014 to 2016 warmed waters and limited necessary nutrients that affected the population of kelp along our coast, but had no effect on the urchin’s survival. Urchins grew “to densities 60 times greater than the historical average,” according to an article by the Greater Farallones Association.
Kelp, a fundamental species, not only supports a large variety of organisms, it is also beautifully intricate. (courtesy of STEVE I. LONHART, NOAA MBNMS)
“All the stars and moons have aligned to produce this [issue],” King says. “It’s a situation where we don’t know 100% of everything going on…but we do know that all this kelp loss happened after the heat waves, the sea star wasting disease and the urchin explosion.”
Whether kelp acts as a habitat, nursery, refuge from predators or food source when living or detached, it is necessary for the productivity of its environment.
“Kelp also can modify the nearshore oceanographic variables,” Lonhart explains. “Kelp can dampen wave energy and impact local currents. It produces oxygen and can alter the local pH of the water. Kelp also serves as an indicator of local health and productivity.”
Organizations like MBNMS and projects like the Giant Giant Kelp Restoration Project are actively working to aid the restoration of kelp. One specific project is located at Tanker’s Reef. Right off Del Monte Beach, Tanker’s Reef is an area that the California Department of Fish and Wildlife designated in April of 2021 for divers and researchers working with them to amend fishing regulations, allowing divers who have recreational sport fishing licenses to collect urchins unlimitedly.
The Kelp Forest exhibit at the Monterey Bay Aquarium has fascinated visitors for decades. (courtesy of MONTEREY BAY AQUARIUM)
For three years, these divers were able to go out and kill urchins, both native purple and red ones, to help the issue at hand. MBNMS participated with Fish and Wildlife to monitor this specific area. The idea was to remove all the urchins from the area so the kelp would grow back. When the three-year permit expired and was not renewed by the state, MBNM continued to monitor without the culling of urchins.
“We go out and dive transects [large tape measures to use on sea floor] and then count and measure numbers and sizes of purple and red urchins,” King describes. “We also note the amount of kelp down there. We count the number of stripes [the stem-like parts.]”
NOAA researchers expressed the importance of the research and monitoring they have been doing for the last three, almost four years. Even though they are no longer able to go out and destroy urchins, there is hope that the work Fish and Wildlife did to help restore the kelp will be proven successful. Meanwhile, this new monitoring could potentially show whether the effects of urchin culling are short-term or long-term.
“Before this past fall, Big Sur was at historic averages,” King says. “This is why it’s such a perplexing issue. Because there were areas that were really hit hard like Northern California and the Monterey Peninsula, but then there are areas that weren’t, like Big Sur.”
While the cause of the kelp loss is not entirely certain, the fact that kelp is absolutely necessary in coastal areas is.
Urchins often eat kelp by the bottom of it’s structure, known as the holdfast, which leads to the detachment of the kelp. (courtesy of STEVE I. LONHART, NOAA MBNMS)
To better understand the ocean and to be able to contribute to current research helping oceanic issues, Carmel High School senior Brianna Sciuto spent this past summer delving into the environmental science of kelp through self-organized diving expeditions. Sciuto designed the research on her own and worked with a PhD graduate through a research program called Polygents in order to write a research paper titled “Monterey Bay Giant Kelp Forests and Their Potential to Mitigate the Impacts of Climate Change on Local Marine Ecosystems.”
“Giant kelp forests in Monterey Bay contribute to the mitigation of the coastal impacts of anthropogenic climate change, making it an indispensable component of local oceanic health,” Sciuto says in her paper. “It is essential that we improve education and outreach with actions such as the dedication of resources to the creation of climate change-related education programs and the inclusion of kelp forest education in local curricula.”
Sciuto isn’t the only one learning more about the importance kelp has played in the ocean’s ecosystem. Researchers at the University of California, Santa Cruz, are working on a project with a grant from the Ocean Protection Council. They are implementing experimental restoration of kelp beds and assessing factors that may contribute to the natural recovery of kelp.
Urchin barrens devastate the ecosystems of kelp forests along the coast. (courtesy of STEVE I. LONHART, NOAA MBNMS)
Organizations and foundations like MBNMS understand that this issue is important and must be researched. As climate change is a growing issue in today’s world, the species and ecosystems affected should be addressed.
“Unsustainable human activity poses a significant threat to oceanic health,” Scuito begins her paper. “Anthropogenic climate change, ocean acidification, warming and pollution interfere with aquatic communities and endanger marine life. We must understand the consequences of these threats to marine ecosystems to inform future endeavors in preservation and regeneration.”
Although kelp forests may seem insignificant from the surface, King shares the influential concept that “when the kelp disappears, so do the animals.”
