Two drunken Welshmen Wednesday escaped with a fine after being convicted of stealing a penguin called Dirk from an Australian theme park after consuming large amounts of vodka.

Former Royal Marine Rhys Owen Jones, 21, and his bricklayer friend Keri Mules, 20, broke into Sea World on Queensland's Gold Coast last month and swam with the dolphins and let off a fire extinguisher in a shark enclosure.

The pair, in Australia on a working holiday, then stole Dirk, Southport Magistrates Court heard.

Their lawyer Bill Potts, who Australian Associated Press reported was wearing a penguin tie in court, said his clients meant no harm.

He said after they awoke the next day with hangovers and found the bird in their room they tried to care for it by feeding it bread and putting it in the shower.

"They tried their incompetent best to care for the penguin," Potts said.

The little bird was eventually found, exhausted but otherwise well, after a couple spotted it in a nearby shallow estuary when they had released it.

The couple said they saw the captive-bred penguin get chased out of the water by another animal -- possibly a shark -- before it was then herded back in by a dog. Sea World workers eventually came to retrieve it.

Potts said the men, who pleaded guilty to trespassing, stealing, and keeping a protected animal, regretted their actions and were deeply embarrassed by the international media coverage of their exploits.

Magistrate Brian Kucks fined them Aus$1,000 ($1,034) each and said they were lucky not to have drunkenly stumbled into the polar bear enclosure.

"You could have found yourselves in a morgue if you'd gone into the wrong enclosure. Perhaps next time you are at a party you will consider drinking a little less vodka," he said, AAP reported from the court.