Perth Zoo produces more than a tonne of organic waste every day, but a composting program is helping to reduce this elephantine environmental footprint.

Between them, the 1,200 animals at the South Perth site produce about 800 kilograms of poo every day.

Perth Zoo's gardens produce thousands of tonnes of green waste every year. ( Flickr: Ross Funnell )

The zoo's extensive gardens, including 4,000 mature trees, add another 700 kilograms of green waste to the daily total.

Dan Baker, the zoo's environmental sustainability coordinator, said the challenge was to find ways to reuse and recycle some of that waste.

"Many years ago we used to sell zoo poo, back in the 1980s, but for various reasons we stopped doing it," Mr Baker told ABC Radio Perth.

"About five years ago we began the journey of trying to re-establish that composting process."

Animals produce 'high grade' manure

When the trial began, only the manure from the giraffes, rhinoceroses and elephants was used.

The zoo's Asian elephants can each produce 60–90kg of poo a day.

Giraffe Kitoto is one of Perth Zoo's premium poo providers. ( Supplied: Paul Fahy )

"We just used giraffe, elephant and rhino poo initially because it is a very high grade, it's fibrous and it gave us the best chance of success," Mr Baker explained.

"After the first year, once we proved that we could do it, we added in all the other animals.

"We now use about 95 per cent of all the manure produced on site, even from our carnivores — lions, tigers, everything goes into this process."

Making Creature Compost

The waste is collected by zoo staff daily and sent to a commercial composter.

There, the manure and green garden waste is processed and turned into a high quality, pasteurised and mature compost product that is free from seeds and pathogens.

Altogether, about 600 tonnes of the zoo compost is produced each year.

"They deliver the good stuff back to us for use on our gardens and we also bag the surplus for sale to the public," Mr Baker said.

And since perfecting the Creature Compost blend, the zoo has managed to reduce the amount of waste it sends to landfill by 45 per cent.