An adventurer has completed a 2,951-mile solo paddleboard voyage from San Francisco to Hawaii, a feat of endurance which lasted 76 days.

Antonio de la Rosa travelled alone across the Pacific Ocean without supporting boats. He braved choppy waters and glimpsed whales – as well as a constant stream of plastic pollution.

The Spanish endurance athlete is believed to be the first person to have completed the journey on a stand-up paddleboard.

He set off from San Francisco, California, on 9 June and reached Honolulu, Hawaii, on Saturday, after paddling up to 10 hours a day on a specially designed craft fitted with a sleeping area and a desalinisation system for drinking water.

The 50-year-old, who documented his journey on Facebook, said he saw fishing nets and other plastic debris daily during his voyage.

“I keep seeing every day some plastic packaging and remains of fishing nets,” he wrote in a 7 August post. “Although it is not much, there is no day that I do not locate some plastic floating. We need to change things as soon as possible.”

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Mr de la Rosa’s vessel had no engines and fitted with solar panels to power his GPS, radio and computer, which allowed him to monitor his location and keep in touch with his family. He was forced to wake up every hour at night to check he had not drifted off course.

He packed three months’ worth of freeze-dried food onto his seven-metre boat, which weighed more than 680kg when fully loaded. Although he a caught some fish to vary his diet, he said he had lost 12kg of weight by the end of his voyage.

Antonio de la Rosa’s paddle boat after docking in Honolulu (Hawaii News Now ) (Hawaii News Now)

After arriving in Hawaii, Mr de la Rosa said he felt “tired but very satisfied”.

He added: “I had to overcome some difficult currents when I left San Francisco, wind sources that pushed me south, several hurricanes that have passed me close, great waves that shook my small boat as if it were a washing machine, sleepless nights, heat and humidity. But I am here, I have succeeded, I almost do not believe it.”

It was not the adventurer’s first endurance challenge at sea. In 2014, rowed across the Atlantic Ocean by himself in 64 days, winning a race against 17 other competitors. Two years later, he paddleboarded through the Arctic Circle.