Threatened Species Commissioner Gregory Andrews found a creek near Curtin choked with plastic bottles, coffee cups and what looked like a can of fly spray on Monday morning.

Mr Andrews, who is broadly responsible for promoting conservation at the national level, said the capital city should be setting an example for the rest of the country.

"I expect more from Canberra," he said.

"Canberra is my community and the nation's capital. When I see that rubbish, I feel like we should be setting an example."

Not only was litter awful to look at, it could also have serious consequences on flora and fauna in the region, Mr Andrews said.

"I used to think of rubbish and littering as selfish behaviour that was sort of diminishing the beauty of the environment.

"But, after I started working as the commissioner, I also learnt about the impacts it can have on our species.

"For many species it can be the number one driver of decline."

In his role, he had come across many gruesome examples of animals being killed by rubbish that polluted their habitat.

"I've seen turtles that have died because they had a straw through their nose. Something as insignificant as throwing away a straw can have such huge impacts," he said.

"Our wildlife doesn't know what's good for them or not. I've seen birds that scientists have cut open and they died because their stomachs were full of balloon ties and bottle tops."

To combat the problem Mr Andrews said he would be organising a river clean-up to coincide with Clean Up Australia Day on March 5.

"I'd encourage people to keep an eye out for that. Let's clean up this litter and send a message that we don't tolerate it in Canberra."