The State Opera says it is facing rising pressure on ticket sales and resources from the Adelaide Festival and other events in late summer and early autumn.

In its annual report, it says its main stage productions last year, including Moby Dick, failed to achieve box office targets.

CEO Timothy Sexton says problems include availability of venues and personnel shortages during March.

He says competition has increased now the Adelaide Festival has become an annual event.

"What we're also facing is, particularly with an annual Festival, it now creates an interesting scenario which previously we only had to face once every two years which is this rainshadow that happens, which is when people don't tend to buy things," he said.

"So you don't bother programming something about a month or two months after the Festival because people are 'festivaled' out.

"The competition is also happening because the number of venues in South Australia is being reduced at an alarming rate. We are losing venues at the rate of knots and the venues that we do have are falling behind in terms of quality because the money is not being spent on upkeeping (sic) them."

Mr Sexton said he believed the Festival Centre was in drastic need of renovation.