STRUCTURES ON THE HORIZON
Twenty-seven oil platforms, all located in Southern California, span from Huntington Beach to Point Conception in Santa Barbara County. Four reside in state waters and 23 in federal waters at depths that range from 100 to 1,200 feet. Many of the platforms, which have been in place for 30 to 50 years, are currently not producing enough oil to make them worth maintaining.
ABUNDANCE OF LIFE
As nature tends to do, it adapted to the towering structures, creating habitats for a multitude of fish and invertebrates amid the metal beams. “These oil platforms are unique relative to natural reefs because they go from the bottom of the ocean to the surface,” says Jeremy T. Claisse, Ph.D., associate professor of biological sciences at
California State Polytechnic University, Pomona. “There’s a lot of water flowing through, bringing plankton to feed the mussels, scallops and anemones that have encrusted the structure.”
Those invertebrates then serve as sources of food for fish, 90 percent of which are rockfish, which are economically and ecologically important to California. While other natural reefs have been fished heavily by recreational and commercial fisheries, it’s likely the platforms have provided shelter where fish have been allowed to repopulate.
Dr. Chris Lowe’s team at CSULB deployed this autonomous acoustic receiver on Platform Edith in San Pedro to monitor for presence and depth of reef fish caught and tagged at this and other nearby platforms. Photo: Bob Wohls
TRADITIONAL DECOMMISSIONING PROCESS
Removing structures that are submerged in 1,000 feet of water is an expensive, technically challenging and risky project. Not to mention the large carbon footprint created by the whole operation and then having to figure out where to recycle the massive and odorous structures. Traditional methods of removal, like the ones used in the Gulf of Mexico, involve dropping explosive charges down the legs of the platform, causing them to rupture at about 13 feet below the surface.
“Then they use cranes to lift it up and cut it, lift it up and cut it,” explains Chris Lowe, Ph.D., professor of marine biology and director of the
Shark Lab at Cal State Long Beach. “The problem is billions of animals use those platforms as their home. All fish with a swim bladder that are within 500 yards of the explosion will die and all invertebrates growing on the platforms will dry up and die. I was skeptical of the data indicating the oil rigs are valuable, but having worked on them for so long, as long as the wellheads can be sufficiently capped to prevent leaking, I’m in favor of reefing.”
Dr. Claisse says that’s not even the biggest issue at hand: “It’s not so much about the fish that are currently living there, but about the habitats the platforms provide over decades so fish can reproduce. Losing the habitat is the bigger effect.”
In 2010, then-governor Arnold Schwarzenegger signed
AB 2503, which created the option of allowing oil companies to turn oil platforms into artificial reefs.
THE PLATFORM PREFERENCE
Over the span of nine years, Dr. Lowe oversaw a number of projects (funded by $660,000 in grants and contracts) that involved a team of 10 CSULB graduate students and focused on researching whether fish prefer living at oil platforms. The findings would help determine if the platforms should be retained or removed. They assessed the habitat value at platforms in Long Beach and used
acoustic telemetry to discover how long fish were staying there.
The next step was to find ways to mitigate the mortality that would occur during full decommissioning by physically moving fish to different habitats. “We caught fish on several platforms in the Santa Barbara Channel, tagged them and translocated them to a
marine protected area off Anacapa Island [12 miles away] across a deep water channel,” Lowe says. “Twenty-five percent of them returned to the platform they were caught at, which really shocked us."
Dr. Lowe’s team deployed this autonomous acoustic receiver on Platform Edith in San Pedro to 24/7 monitor for presence and depth of reef fish caught and tagged at this and other nearby platforms. Photo: Bob Wohls
Left to right: CSULB alumnas Erica Jarvis-Mason, Kim Anthony and Heather Gliniak catching and tagging rockfishes at Platform Gail in the Santa Barbara Channel. Tagged fish were translocated to the Anacapa Island State Marine Reserve. “The overarching lessons I learned were not just managing people, performing different tasks and coordinating their activities so we were all in lockstep with one another, but also managing different personalities, needs and skill sets,” Anthony says.
Dr. Chris Lowe pictured with a real-time acoustic receiver buoy prototype. Instead of requiring a diver to retrieve an underwater receiver, this special buoy has a cellular modem and allows for real-time detections of tagged fishes and sharks and can provide text alerts of detections.
“We also caught fish off the natural reef and moved them to the platform and then caught fish off the platform and moved them to the natural reef. We found that the fish caught on the natural reef stayed on the platform and the fish we took off the platform and moved to the natural reef came back to the platform.”
With direction from Lowe, CSULB alumnus Chris Martin led the study design, data collection and analysis of fish community data. “This work was published as my thesis as well as two separate peer-reviewed journal articles,” says Martin, who is now an environmental scientist at Metro Vancouver Regional District. “My CSU experience was no doubt invaluable, and I wouldn't be in my current senior position without the skills and knowledge I gained.”
CSULB alumnus Carlos Mireles CSULB catching reef fish underwater at Platform Edith for tagging and monitoring of depth and presence at this and other nearby platforms. “The experience taught me how to lead a large and diverse field team, coordinate with stakeholders, perform underwater SCUBA based research in challenging conditions, perform data analysis and share scientific findings through public presentations and written reports/peer reviewed literature,” says Mireles, who is now a fisheries biologist for the California Department of Fisheries & Wildlife in Santa Barbara.
IN THE FIELD
At Cal Poly Pomona, Claisse has been studying fish behavior around oil platforms for almost a decade, expanding on datasets developed by Milton Love and Ann Scarborough Bull, researchers at UC Santa Barbara. “We focused on taking that data and converting the counts—how many fish, how big they were and which species—into a uniform metric that can be used to compare platforms to natural rocky reefs,” he explains. “That way, you can compare the amount of production between the two to get a sense of how they’re functioning as an ecosystem.” Claisse and his team found these platforms are among “the most productive habitats for fish anywhere that’s been studied in the world—about 27 times more productive than the natural rocky reefs in our region.”
CPP graduate student Chelsea Muñoz Williams says her research on the platform project helped her see the value of applied science and how science informs policy. “From an environmental standpoint, one would assume complete removal of these platforms and restoration to the original natural state would be the best ecological option,” says Williams, a research associate, grants manager at Occidental College. “However, these structures act as refugia for hundreds of species of fish and invertebrates throughout the water column, none of which would exist over soft, sandy substrate.”
As part of Chelsea Williams’ master’s thesis research at Cal Poly Pomona looking at the geographic- and habitat-related variation in age and growth patterns in Garibaldi (California’s State Marine Fish), she captured and chemically tagged some of the fish to validate her aging methods.
Sea lions look on as Dr. Jeremy Claisse surveys the benthic invertebrates and habitat at Begg Rock, a pinnacle reef 80 miles off the coast of Los Angeles that is now part of California's statewide marine protected area (MPA) network. Claisse is part of a team that has been conducting surveys of rocky reef and kelp forest habitats inside and outside of California's MPAs in Southern California.
Photo: Jonathan Williams
ADDING TO CALIFORNIA'S BLUE ECONOMY
Environmental groups are pushing for complete removal of the oil platforms, calling them unsightly and citing the possibility of oil leaks. Others claim the locations can serve multifunctional purposes, including as dive sites and anchoring points for offshore aquaculture.
“If you have this platform offshore and it already cost millions and millions of dollars to put into place, why not retrofit it for something else, like wave energy or wind energy?” Lowe poses. “One of the other options discussed is to take off the superstructure and just leave a flat platform to use as a roosting habitat for seabirds. My dream is to convert one of them into a marine lab.”
WHAT THE FUTURE HOLDS
While the state and federal government are determining the exact process, 10 platforms are projected to be decommissioned in the Golden State by 2030. The first one will likely be Platform Holly in Santa Barbara, which the state owns as a result of the petroleum company claiming bankruptcy.
Lowe and Claisse are hopeful the deciding bodies will take their research findings into consideration. Whatever transpires, they are grateful for the rich experiences gained by CSU students. “With their participation in the oil rig projects, many of my students learned how to do science in difficult places and how to deal with policies,” Lowe says. “They got a lot more than a master’s degree.”
For more information on how the CSU is working to solve the biggest threats to California’s oceans, check out our
oceans series.