Zoo wants to be No. 1 in No. 2 | The State

Riverbanks Zoo is selling compost made from animal manure: Let the scatological phrases begin!

Zoo poo. Zoo do. When ordinary poo won't do.

Pile it on. Join the movement. Heavy doody.

Riverbanks is having fun with the product it'll market as Compoost, but it's serious stuff, too.

The zoo used to pay thousands of dollars a year to a disposal company to get rid of these animal wastes. The composting effort - limited at this point to elephant, giraffe and zebra manure - cuts down on the waste load by about 1,500 pounds each day.

"Not only are we saving on disposal, but what was once a hindrance has become an asset," said John Davis, who doubles as curator of mammals and conductor of composting.

Davis has been trying to start a composting effort at Riverbanks for years, but he and others at the zoo feared it wasn't feasible.

"We produce so much waste every day, it was overwhelming," Davis said.

Finally in 2008, Davis persuaded zoo leadership that it could be done. The zoo's conservation fund helped pay the $25,000 cost of creating a concrete composting pad, with raised edges and a drain collection system to prevent rain runoff. The pad is in a wooded area behind the elephant exhibit and close by the giraffe and zebra barns.

The first manure was dumped on the pad Jan. 26, 2009. And nearly every day since then, the poop has been mixed with just the right amount of hay (somewhere in the 50-50 to 60-40 range) to start the composting process.

The stinky stuff is piled in a line 10 feet wide by 6 feet tall and monitored for temperature and moisture. The temperature deep in the pile (measured by a 4-foot-long thermometer) reaches 120 degrees within a few days and as high as 150 degrees after six weeks, Davis said.

Flies hover around the new stuff. The older stuff is mostly fly-free because the interior heat kills fly larvae. After about three months of turning and watering, the composting process is finished and the manure and hay have turned into dark, moist, odor-free dirt.

Zoo keeper Stacy Hitt keeps track of a "birthday" for each zone of the two long compost piles on the pad, and each zone eventually is "retired" to piles of finished compost in the surrounding woods.

Riverbanks has used the early composting product in the botanical garden and in landscaping plots throughout the zoo. Employees were encouraged to take some home and try it in their home gardens.

All the reports have been positive, making the zoo comfortable in marketing the Compoost to the public. The price is a little high - $5.25 for a pint container or $13 for 2 gallons at the zoo gift shops and sales carts or $43 for a cubic yard (ordered online and picked up in your truck after hours).

Riverbanks doesn't claim its compost is any better than others. But the origin gives it some cachet, and buyers should appreciate that the proceeds go to Riverbanks' Conservation Support Fund, which pays for wildlife conservation efforts around the world.

With all of the potential positives, the odor from behind the elephant barn smells sweet to zoo officials.

"I love this project," said Hitt, whose e-mail address (first initial, last name) makes her the perfect fit for dumping the daily trash-can-sized loads of manure on the pad. "It's so rewarding to watch this. All of this would be going to a landfill otherwise."

Watch John Davis explain the 'Compoost' process from start to finish: