Study in Irony: Researchers Say Oil Rigs Are Great for Fish

The platforms off California's coast might provide some of the world’s best marine habitat.

(Photo: EMP Photography/Getty Images)

Oct 21, 2014· 2 MIN READ
Taylor Hill is an associate editor at TakePart covering environment and wildlife.

Those giant offshore oil platforms dotting California’s coastline look like the least friendly marine habitat you could find.

For many people, the structures conjure up memories of some of the worst environmental disasters in American history, from the Santa Barbara oil spill of 1969 to the Deepwater Horizon catastrophe in 2010.

But fish don’t care.

They’ve turned the oil rigs into some of the most productive ocean environments in the world, according to a new report by researchers at Occidental College and the University of California, Santa Barbara.

The scientists, who studied 16 offshore oil platforms over a 15-year period, found that on average, the artificial structures are home to 27 times as many fish as natural rocky reefs in the area.

But it’s not just a California thing. There are 10 times as many fish on the platforms as are found in natural marine habitats worldwide.

“We were surprised by how large the numbers were relative to the research done elsewhere,” Jeremy Claisse, an Occidental biologist and the study’s lead author, said in a statement. “On the other hand, given the size of these structures—they range from about 150 to 650 feet tall—and the staggering numbers of fish consistently observed there, it’s not that surprising.”

Platform Gilda Midwater with a school of bocaccio juveniles.

(Photo: Scott Gietler)

But it’s not just their sheer size that makes oil platforms such a habitat-forming hot spot; it’s their verticality.

“Normal rocky reefs are vertically challenged; they’re not extending up into the water column hundreds of feet the way these platforms are,” said Milton Love, a UCSB professor and a coauthor of the study.

For California’s 60 species of rockfish, the platforms allow adult fish to hunker down on the ocean floor, while their offspring congregate higher up in the water column, where they’re protected from predators by the oil rig’s pillars.

“If there was a natural reef that was 300 feet tall, you’d probably see fish numbers that are similar to the platform, but the ocean tends to wear away things built like that,” Love said.

The findings could prompt a rethink of the best way to decommission the thousands of offshore oil and gas platforms around the world, especially as ocean acidification from climate change accelerates the destruction of coral reefs.

“Rather than completely removing the structures, underwater portions could be left intact to provide habitat to supplement increasingly threatened fish populations on natural reefs,” the study states.

It won’t be an easy sell.

“Some people are so angry with the oil companies, they want the platforms taken out no matter how many animals are killed,” said Love. “But others see the platforms as fully functional reefs. Why would we want to blow them up?”

Claisse said the study’s findings offer lessons for offshore wind farm developers.

“The most exciting thing for me is that this study could provide a basis to start thinking about how to modify new renewable energy-generating structures like wind farms or wave energy devices in ways more beneficial to marine conservation and fisheries,” Claisse said.

“From a biological standpoint, the fish don’t know if it’s an oil platform or the bottom of a wind turbine,” he added. “Complex structures can provide a lot of different kinds of habitat to various species of fish at multiple points in their life cycle.”