Legendary oil and natural gas wheeler dealer T. Boone Pickens, 89, announced Friday he has closed his Dallas-based energy hedge fund.

Pickens, who founded and has chaired BP Capital and TBP Investments Management since 1996, posted his decision online.

“It’s no secret the past year has not been good to me, from a health perspective or a financial one,” he wrote. “Health-wise, I’m still recovering from a series of strokes I suffered late last year, and a major fall over the summer. If you are lucky enough to make it to 89 years of age like I have, those things tend to put life in perspective. It’s time to start making new plans and setting new priorities.”

He noted that this was the third time he was basically walked off of a job. The first, he said, came in 1953, when at age 25 he left a job as a geologist for the former Phillips Petroleum Co. The second came in 1996, when he resigned from Mesa Petroleum, which he had founded and led as CEO for nearly 40 years.

“In both instances, I had a plan, and my life was much richer as a result,” he said. “Today, I’ve decided to walk off the job for a third time and have decided to close the doors on the energy hedge fund I’ve successfully run since 1996.”

Running BP Capital “has been one hell of a roller coaster ride. I’ve seen oil prices bounce around from $10/bbl up to $147, down to $26 and now appear to be inching up ever so slowly. I’m ecstatic that I’ve hung on long enough to see it all unfold. I’ve thrived and profited on the volatility in the energy space. But for me, personally, trading oil is not as intriguing to me as it once was.”

While he early on gained dealmaking notoriety — or celebrity, depending on the interpretation — for attempting leveraged buyouts of energy companies, he also has done much more to push for U.S. energy independence.

Nine years ago the billionaire launched the Pickens Plan with a broad flourish and national support to reduce U.S. dependence on foreign oil. Unconventional producers already were working to fulfill that pledge and since then have nearly succeeded.

“That threat has been diminished considerably and I like to think putting a spotlight on the problem — along with stunning innovations and success in America’s oil and gas industry — has helped us drill our way out of that challenge,” Pickens said. “It has certainly been a factor in putting a brake on price volatility.”

Pickens also has been a long-time champion of domestic natural gas, forming Pickens Fuel Corp. in 1997, which promoted gas as the best vehicular fuel alternative. Reincorporated as Clean Energy Fuels Corp. in 2001, the company builds and owns natural gas fueling stations across the United States and in Canada. He remains on the Clean Energy board.

Pickens also has supported federal legislation to advance natural gas-fueled transportation, as well as pouring money into various gas technologies.