A rescued green sea turtle will be released this weekend back into the Gulf of Mexico, carrying the ashes of a self-taught Texas oceanographer who founded the rehabilitation centre that nursed it back to health.

Thousands are expected to attend a ceremony on Saturday that effectively allows Tony Amos, who devoted his life to helping the endangered reptiles, to do so once more in death. His final voyage comes on a stretch of beach named in his honour.

Amos, 80, died of complications from prostate cancer on September 4, mere days after Harvey roared ashore as a fearsome Category 4 hurricane. It caused extensive damage to the Animal Rehabilitation Keep for ailing sea turtles and aquatic birds that Amos opened nearly four decades ago.

But the turtles there weathered the storm well — as their counterparts in the wild also appear to have done, scientists say.

An early hatching season meant most turtles headed to sea before the storm arrived, with their eggs already hatched rather than lying on the beach to be subsumed. Also, few turtles became stranded inland as Harvey pulled the tide far out and, since the punishing winds and rains subsided, only a relatively small number has washed back onshore or been found among storm debris.

"This certainly could have been worse," said Tim Tristan, executive director of the Texas Sealife Center, a nonprofit rescue and rehabilitation facility in Corpus Christi, close to where Harvey first made landfall. Five of the world's seven sea turtle species are found in the Gulf of Mexico and have been documented in parts of Texas: green, hawksbill, Kemp's ridley, leatherback and loggerhead.

A green turtle credit: Getty Images

At Amos' turtle and aquatic bird center in the Harvey-ravaged beach town of Port Aransas, the hurricane smashed roof tiles and solar panels and collapsed parts of buildings. Partially submerged, concrete tanks housing around 60 rescue turtles were also damaged, but the animals weren't harmed.

Staff arriving by pickup truck had to steer though downed powerlines and assorted destruction to reach the rehabilitation facility just after Harvey passed.

"We had turtles crawling around back there," said Jace Tunnell, director of the Mission-Aransas National Estuarine Research Reserve, which encompasses Amos' rehabilitation center. Animals well enough were released to sea, but those who weren't went to Mr Tristin's facility.

In Port Aransas, Mr Tunnell said a few turtles were discovered amid Harvey's wreckage, but "nothing too crazy."

Amos was born in London and went to Bermuda at 17, trying unsuccessfully to engineer a colour, flat-screen television. Having never graduated from college, he moved to Port Aransas in 1976 and became an oceanographer for the University of Texas Marine Science Institute.

Three years later, the Ixtoc I exploratory well exploded in the Gulf about 50 miles from Mexico's coast, and Amos saw the devastating effects of the resulting oil spill on sea life. He later founded the Animal Rehabilitation Keep, which still helps hundreds of turtles and birds annually — tackling everything from pelicans that swallow plastic to turtles stricken with a tumor-causing virus.

Known for a long, white beard that helped him play Santa Claus at Christmas, Amos retired in 2003 but continued working, collecting and analyzing debris on Texas beaches and painstakingly entering findings in databases. He also sailed on marine voyages throughout the world.

"I considered him a genius," Mr Tunnell said. "He was a great oceanographer but he was so humble."