The former Reagan administration official admitted to feeling a mix of excitement and nerves as he answered questions on a range of topics.
"More nervous than excited right now," he said.
US part of the Pacific
The ambassador warned of cash-strapped Pacific nations falling victim to "pay day loan diplomacy" used by China.
"I think it's on us all of the allies and the Western Nation western or liberal democracies to educate people about the the dangers of these loans," Mr Culvahouse said.
"The fact that the money looks attractive and easy up front, but you better read the fine print."
He said the increased attention to the issue reflected the growing importance of the Indo-Pacific region.
"We are a Pacific nation too and maybe we need to spend more time focusing on our own self-interest."
No plans for Trump visit
US President Donald Trump won't be visiting Australia any time soon, with Washington's new man in Canberra dampening expectations the president is planning a trip down under.
"The president's got a busy schedule," Mr Culvahouse said in his first Australian press conference.
"I was talking to the White House before I left, that is still an option that's being considered, I do expect a number of very senior administration officials with whom I met to visit Australia this year.
"I would expect that there will be further meetings between the president and the prime minister of Australia, whomever he or she may be. But the president's schedule is still being negotiated, still being formulated."
The ambassador first visited Canberra in September after being approached for the position.
He laid a wreath at the Australian War Memorial before looking out at Parliament House over Lake Burley Griffin.
"I then and there decided that serving as the 26th United States ambassador to Australia would be the capstone of my career," Mr Culvahouse said.
"I never regretted that decision."
Mr Culvahouse has arrived in Australia just two months out from the federal election due in May.
Mr Culvahouse plans to meet federal government and opposition officials before the election campaign kicks off, pledging to share any intelligence the US has to offer.