New $5 note introduces our Gaga bird

If the new $5 note's designers had taken the same liberties with the Queen as they did with the Eastern Spinebill, her Majesty would look like a cross between Dame Edna and Lady Gaga.

The complex design for the new note, released on Tuesday, is aimed at thwarting counterfeiters.

But twitchers - as birdwatchers are known - could be just as miffed as the crooks.

The $5 banknote depicts the Prickly Moses wattle and the Eastern Spinebill.

What's not mentioned is that the Eastern Spinebill appears to have had something of a makeover.

In real life, the bird has a subdued colour palette ranging from white, through tan, darker brown and black.

The picture of the note supplied by the Reserve Bank of Australia suggests a riot of colour - blue, green, magenta and black.

Steve Anyon-Smith, a professional birdwatching guide and author of a book on birdwatching for the NSW National Parks and Wildlife Service, described it as bizarre.

"It's only similarity to an Eastern Spinebill is the general shape," Mr Anyon-Smith told AAP.

The RBA said the note's design followed "a process of extensive consultation with subject matter experts".

But Mr Anyon-Smith says it appears those experts may not have included ornithologists.

The Eastern Spinebill was a beautiful bird in its own right and didn't need enhancement.

"Yeah, if it was a boring bird, jazz it up a bit, but it looks like a hybrid between a spinebill and something from South America," he said.

The RBA's anti-counterfeiting measures built into the new notes will be explained in a public awareness campaign in coming months.