What do we do with our heaps of herbivore poop? We create soil! Our on-site composting program diverts tons of waste from landfills.
Here's how we convert animal waste to usable soil: Manure from giraffes, elephants, zebras and other plant-eaters is mixed with hay and straw (soiled from use as animal bedding) along with scraps of fruit and vegetables and coffee grounds from the staff kitchens.
It is thrown into a machine known as a "scapper" which chews up the hay and straw. This enables the mixture to be sent to the composting machine. Here a giant hydraulic compression ram stuffs the entire mixture (along with a special compound to accelerate the breakdown process) into a giant plastic bag shaped like a tube. The bag contains small vents to release the gases that are produced.
Over the next few weeks, this bag is filled until it reaches a length of about sixty feet. Then, a new bag is started alongside. These long bags sit in the sun, allowing the mixture inside to heat up. When the compost heats up to 130-150 degrees Fahrenheit, pathogens are destroyed. In three months, the compost is ready.
The finished product is an incredibly rich and 100% organic compound that amends the soil and allows our horticulture department to grow healthy and beautiful plants throughout the zoo grounds.
Find out more through this Oakland Zoo blog:
In the Field N. America
In the Field Africa
In the Field Asia
In the Field L. America
In the Field Global
The Green Zoo
Reduce, Reuse, Recycle
The Green Cafe
Shopping for the Planet