The entire surface area is teeming with life: the aging oil platforms that transformed into underwater habitats.
On a recent afternoon in August, Ann Scarborough Bull traveled two miles from the shore of Santa Barbara on the research boat named the Danny C. The team of marine biologists had a unique target in mind: an abandoned oil rig that stood tall like an overlooked high-rise on the horizon.
The group was not intrigued by the platform itself, but rather what was hidden below. Upon reaching the old structure, known as Holly, they deployed a vehicle the size of a car that could be controlled remotely into the water.
At that location, they observed a vast number of young rockfish seeking protection within the large metal framework, alongside swaying white anemones, groups of mussels, and silver jack mackerel.
For several years, experienced marine scientists have been studying this incredible phenomenon. In 2015, Holly was decommissioned, but it is just one of the 27 oil rigs constructed off the California coast many years ago that have now turned into thriving ecosystems.
Although not naturally occurring, their platforms have been submerged in the muddy seabed for a significant amount of time, ultimately becoming integrated into the marine ecosystem. This has created a habitat for various marine animals, such as mussels and barnacles, which then attract bigger fish and sea lions seeking shelter and sustenance.
After 25 years of researching the rigs, Bull concludes that “These locations are highly productive for both commercial and recreational fishing, as well as for invertebrates.”
As California and the United States move towards cleaner energy and away from offshore drilling, there is a growing discussion about what to do with the unused rigs. Some believe that these rigs are harmful to the environment and should be completely removed. Others, including many scientists, argue that we should utilize these unplanned habitats and that getting rid of them goes against moral principles. In other regions of the globe, oil rigs have been successfully transformed into artificial reefs through a program called “rigs to reefs”.
According to Milton Love, a researcher at the University of California, Santa Barbara, who was present on the boat with Bull, the issue at hand is one of moral principles. Love was first exposed to the oil rigs as a college student in the late 1960s while working as a professional fisherman and gathering fish from the rigs for an aquarium, around the time when the platforms were being constructed. He recalls, “There was a plentiful abundance of fish. That memory stayed with me.”
Upon his return to the platforms as a professor in later years, Love was taken aback to discover a wide range of fish communities at each rig. Those closer to shore were dominated by surfperch, while rigs further out were home to more ocean fish. This also brought about a feeling of discomfort for Love as he observed the discussions surrounding the creatures. Eventually, he came to the realization that removing these creatures was ethically questionable.
The fish are unaware of their involvement in a fossil fuel system that is contributing to a climate emergency – they simply see a solid structure with attached invertebrates, providing a place for shelter.
Bull agrees. “If you take away habitat, then there’s no going back,”she says. “You would never allow the willful destruction of a kelp bed, or of a rocky reef, even though rigs have similar biodiversity.”
An ecosystem emerges
As the saying goes, life has a way of persisting, especially in the ocean.
Love suggests that if a tire is dropped off a boat near the shore, within a month, a new species similar to the brown rockfish will inhabit it, swimming in and out of the rubber material.
The statement also applies to the rigs. The oil rigs in California were constructed from 1967 to 1989, and a significant number are approaching the end of their lifespan for extracting fossil fuels. Out of the original 27 rigs, only 15 are currently in operation.
After being placed on the ocean floor, the metal structures were likely soon inhabited by small plankton looking for a surface to cling to. Over time, other organisms began to join, with barnacles being the first to arrive and eventually being replaced by mussels. Within a few months, fish began to reside in the rig structures, as the lattice metal offered better protection from predators compared to the open exposure of sand.
In just a year or two, a complete ecosystem emerged. According to Love, “Nature dislikes empty spaces,” which is why every inch of a platform is filled with living organisms.
After 20 years of first encountering the rigs, Love returned to UC Santa Barbara where he was now a marine biologist. It was then that he realized the lack of scientific studies on the relationship between oil rigs and fish populations.
The findings of Love, Bull, and their colleagues have been astonishing, both in terms of the diverse sea creatures found and the way they utilize the rigs. Through diving, submarine use, and remote operated vehicles, they have explored the area and estimated that there are likely billions of animals, ranging from barnacles to mammals, that depend on the rigs for shelter.
Based on a joint study conducted in 2014, the rigs were identified as highly “productive” ocean environments, meaning they had a high concentration of fish and other organisms relative to the amount of space they occupied. The study found that the rigs were approximately 27 times more productive than the natural rocky reefs found in California.
Jeremy Claisse, a professor at California State Polytechnic University, Pomona, collaborated with Love and Bull on the research. He expressed his surprise, saying, “During my time in college and graduate school, I learned about the high productivity of coral reef and estuary ecosystems. However, the results of our calculations showed that these systems are just as productive for fish, which was unexpected.”
Further research revealed that certain types of rockfish have a significantly higher reproduction rate of 10 to 100 times at artificial platforms compared to natural reefs. This is due in part to the fact that larger adult fish are often caught by fishermen at natural rocky reefs, while they are less likely to be caught at rigs where they have greater protection.
In certain situations, the platforms serve as a vital habitat for entire fish populations. In 2000, Love discovered that the rigs housed approximately one-fifth of the yearly surviving juvenile rockfish, a species that is both commercially valuable and overfished. Another research project, co-authored by Love in 2012, involved tagging lingcod and rockfish and transferring them to a natural reef in a protected area of Anacapa Island across the Santa Barbara Channel. Out of the relocated fish, 25% returned to their original home on the rig, covering a distance of over seven miles. Some made this journey in just 10 hours.
Should they remain or should they depart?
In 1896, the first offshore oil platform in the United States was constructed on a pier in California. This pier is located in the waters off Santa Barbara county, where there is currently debate over the future of these rigs.
The discussion surrounding the future of these remnants of the petroleum industry is not limited to this particular state. Similar situations have been successfully addressed in other regions, either by completely removing the rigs or repurposing them as artificial reefs. In the Gulf of Mexico, where the rigs are located in shallower waters, the government has designated at least 573 platforms as artificial reefs. Some of these have even been integrated into national marine sanctuaries.
The same could be done here, although the technical and legal landscape is trickier. The rigs are submerged in 800 to 1,000ft of water – a depth that has never been decommissioned before – and would require explosives to dislodge them from the seabed, then huge cranes and cargo ships to remove them. It’s costly in terms of carbon footprint but also in dollars: the most recent estimate for removing all platforms off of the California coast totals $8bn, according to Bull.
In 2010, the former governor, Arnold Schwarzenegger, initiated a policy that permitted oil companies to convert their platforms into artificial reefs. The money saved from not having to completely remove the rigs would then be donated to a state conservation fund.
For Emily Hazelwood, a marine conservation biologist and offshore energy consultant who consults on rigs to reefs projects, the idea is win-win-win: “The state wins by getting an endowment, the environment wins because the reefs get to stay, and the oil and gas companies also win by saving money.”
Environmental organizations do not view this as a victory. They argue that the presence of rigs on the ocean’s horizon is unsightly and that the plan allows fossil fuel companies to avoid responsibility for properly disposing of their harmful products. Some have even labeled the plan as “rigs to grief”. Linda Krop, the lead attorney for the non-profit Environmental Defense Center, states that her group has been addressing the issue of rigs since 1996, when Chevron was mandated to remove four platforms. However, the company failed to completely clean up and left behind significant amounts of hazardous debris in the form of 20-foot-tall mounds on the ocean floor.
Krop states that her team desires a pristine marine environment and believes that complete removal would facilitate the ecosystem’s restoration to its natural state.
According to the researchers, tests conducted at the site indicate that the fish in the vicinity of the platforms do not have significantly higher levels of heavy metals compared to those living elsewhere. Additionally, it is mandatory for the companies to properly seal the wells once they have reached the end of their lifespan.
For Love, it simply feels wrong to remove something that’s home to millions of creatures. “It just pisses me off, the hypocrisy of environmental groups who say: yeah, we’re all for biodiversity, except on artificial stuff, and then they can all die,” he says. “It drives me insane.”
He compares the situation to a depleted mine that a mining company wants to shut down, but has since become a habitat for rabbits, birds, and deer. Should we destroy the mine and harm these animals, or find a way to coexist with them? In this scenario, people would object to harming the animals, yet they may not have the same reaction if the situation involved sea anemones instead of Bambi.
Hazelwood hopes that people will view the structures beyond their appearance from a beach chair. She wants them to see them as more than just imposing industrial structures, but rather as dynamic ecosystems that thrive beneath the surface.