AN AUSTRALIAN-born Commander on an American navy ship has described how he first heard about the Roleystone bushfires and instantly knew he wanted to help the victims.

Commander Matthew Roberts is one of 300 US sailors that arrived in Fremantle this morning on board the USS Shoup.

The sailors will be in Perth for several days but it won’t be all rest and relaxation for the crew.

More than 20 sailors on board the ship will help those affected by last week's fires.

The sailors will help clear sites, roads and parks that were completely destroyed.

Cmd Roberts, who was born in Sydney, said he first heard about the bushfires when his dad in Sydney sent him an email.

“My dad sent me an email ... about the fires and so I started surfing the net trying to find some news about it," Cmd Roberts said.

“It was at that time that we got in touch with the US Consulate (in Perth).

“I asked instead of doing our normal routine of going to an orphanage or cleaning up a park, if we can get involved in the cleanup in Roleystone.”

Cmd Roberts said some of his family near Sydney had experienced bushfires in the past.

“We just hope to give back to the community for welcoming us here,” he said.

“Instead of sitting at a pub and kicking back we want to take some of the energy we have and help these people out."

The USS Shoup arrived this morning directly from the fifth fleet area of operations where she has been conducting counter piracy operations in the Gulf of Aden.

Commanding Officer Joe Nadeau said he was thrilled to be in Perth.

“I have family in Fremantle and my wife’s family lives in Mindarie, it feels like we are coming home,” Cmd Nadeau said.

“I was lucky enough to come to Bunbury in 2002 … Australia is just a great place to visit.”

Gunners Mate Jason Lee-Shaw, who has been in the US Navy for four years, said he was looking forward to taking in the Australian culture on his first visit to the country.

"I can’t wait to take in all the sun and the culture,” Mr Lee-Shaw said.