Perth Zoo's composting program – which manages the more than 1 tonne of organic waste produced per day at their zoo south of the city – has reduced the amount of waste sent to landfill by almost half. The zoo recognises that improving sustainability is a critical component of protecting the wildlife habitat and biodiversity, as well as reducing overall environmental impact.
Their 'Creature Compost', which is made from the animal and plant waste collected by every day, does more than just reduce landfill – it helps fertilize their own gardens and generates income through public sales.
The zoo's 1200 animals produce up to 800kg of poo each day, with approximately 10 per cent of that coming from the Asian elephants alone. When this is added to the 700kg of green wasted generated daily by the zoo's 4000 trees, the result is around 600 tonnes of high quality, seed and pathogen-free compost each year.
Other zoos around Australia are also doing impressive things to manage their organic waste and reduce their environmental impact. Zoos Victoria has become the world's first carbon neutral zoo and is aiming for a target of zero waste by 2019. Like Perth Zoo, they will achieve this in part through composting, with help from their in-vessel composter Hot Rot. Zoos Victoria also generates revenue from their compost, making 'Zoo Gro', which is used as both a soil conditioner and organic fertiliser.
In NSW, Taronga Zoo in Sydney and Western Plains Zoo in Dubbo also collect all their waste to be processed into compost as part of their sustainability program, 'Taronga Green'. This program also addresses energy management, water use and reuse and the waste generated by the zoo's estimated 1.5 million yearly visitors.
And these environmental efforts are not just occurring in Australia. In the US, the Detroit Zoological Society has built an anaerobic biodigester – the first of its kind – to use animal waste for energy. While similar to a system in place in Munich Zoo, Detroit's biodigester uses an anaerobic environment to bacterially break down waste, resulting in a renewable energy can then be converted to electrical power. It is estimated that the power produced just from the zoo's 480 tonnes of animal waste will meet up to 10% of its energy requirement, and will leave a negative carbon footprint in doing so. The by-product of this is a high-quality fertiliser, which, is sold to the community under the evocative name 'Zoo Poo'.
- Compost your own green waste – Use Zoos Victoria's compost guide
- Engage with and support your local zoo's sustainability efforts, for example Taronga Zoo's Project In Situ, Project Habitat, or Project Babbler
- Buy Zoo Gro or Creature Compost to use on your garden: Zoo Gro