Dolphins make a rare splash in Melbourne’s Yarra River

A pair of dolphins have been filmed gliding through the Yarra River in Melbourne’s CBD this morning.

Video obtained by 9NEWS showed the mammals swimming through the murky body of water near the Botanic Gardens.

The city section of the Yarra is usually dotted with rowers at dawn, but this time around the dolphins were on their own.

Their fins and tails made visible ripples, with just a whisper of wind keeping the river calm.

Dolphin Research Institute executive director Jeff Weir told The Age in 2009 that spotting the mammals in “metropolitan waterways was unique”.

“There really aren't many places in the world where you've got  four million people living around the waterway where these sorts of things still happen,” Mr Weir told the newspaper.

According to the latest data from Victoria’s Environmental Protection Agency (EPA), the Yarra is unsuitable for humans to swim in.