At zoos, the sweet smell of excess Mounds of animal manure used to be a problem at the Baltimore Zoo. Now, as at other zoos, it's becoming a marketable commodity.; Baltimore... or less


Dolly and Anna, the Baltimore Zoo's two African gray elephants, produce about 300 pounds of droppings a day - each. Drew Norman wants all of it - and the giraffe, hippo and rhino manure, too.

An organic farmer in Whitehall, Md., Norman receives about 25 tons of this so-called "zoo doo" a year to use on his 5-foot-tall, 600-foot-long compost pile at One Straw Farm.

"It doesn't smell bad, really," he swears, then adds, unnecessarily: "You wouldn't want to, but you could eat compost and it couldn't hurt you."

That unappetizing thought aside, zoo animal manure is going like, well, hot cakes across the country. Over the past several years, the once-problematic byproduct has become a source of revenue for zoos nationwide.

A few, like the Woodlawn Park Zoo in Seattle and the National Zoo in Washington, have started their own composting programs, selling the resulting fertilizer to eager gardeners.

The Memphis Zoo is one of many that sends its manure to a Memphis company, Zoo Doo Compost Co., which composts it and then presses the remains into animal shapes with names like "Animal Crappers" and "Dung Buddy."

The company, which originated and still licenses the catchy Zoo Doo name, has agreements with about two dozen zoos around the country and made $500,000 last year selling its wares in catalogs, gardening centers and zoos.

The Baltimore Zoo used to pay $40 per ton to send its animal waste to a landfill. With the two elephants alone producing a ton of manure every few days, the cost was adding up. Then about six years ago, Norman met a woman from the city Parks and Recreation Department at his stall at the 32nd Street Farmers' Market.

"At first we were just talking about leaves, and that maybe I

could get the leaves from Baltimore City to use in my pile," he said. "But then Baltimore City said they wanted to keep all their leaves, and she said, 'Well, how about the zoo manure?' and I was like, 'That's even better!' "

While Norman now gets the lion's share of the zoo's manure - as elsewhere, only from herbivores (plant eaters), because of health concerns about waste from carnivores - not all of it leaves the zoo. Steve Linda, the Baltimore Zoo's chief horticulturist, said the zoo has a small composting pile of its own that it uses to fertilize the grounds.

But because the zoo is located on a hill and doesn't have a lot of open land, there's no room to compost all the manure as Seattle and Washington do.

"I think it's a great idea, but we don't have the room, and we don't have the manpower," he says.

The Washington National Zoo makes about $15,000 annually from its 8-year-old waste-recycling program, said Rick Reichley, a self-proclaimed zoo doo expert. Its compost site is located at the Old Soldier's Home near the Walter Reed Medical Center.

It takes about six months for the dung to break down into usable compost, he says. "We replenish it pretty much every day," he adds. "It's not like the animals take a break."

Some gardeners prefer not to wait for compost, believing fresh is better. The Ringling Bros. and Barnum & Bailey Circus has become a source for some brave souls, who, gloved, gowned and armed with shovels and pails, wait outside its tents for bins full of steaming manure.

Linda, the Baltimore Zoo horticulturist, said he understands the attraction. "I'm the one at the end of the parades eyeing the bags of horse manure on the corners," he says.

The folks at Zoo Doo Compost Co. claim their products are twice as rich in nitrogen as cattle and horse manure, and virtually free from hormones and weed seeds because of zoo animals' specially formulated diets. But not everyone is so sure that manure from zoo animals is better manure.

Lewis Smith, who is at work on a manure management research program for the Agriculture Research Service in Greenbelt, says fertilizer is fertilizer, no matter what animal it comes from.

"It really depends on what the animals eat," he says. "Just because it comes from a bigger animal doesn't mean it has more nutrients in it."

Don't tell that to Drew Norman. He says the vegetables he grows on his

organic farm have shown definite improvement since he began using the zoo doo in his compost pile. He used to use chicken manure, he says, which smelled worse and didn't work as well.

"We don't have to spray for insects as much," Norman says. "The plants themselves grow much more consistently."

He says he puts about $30 into every ton of compost he produces - and he produces about 500 tons of it a year. Norman says he can turn zoo doo into fertilizer in about two months.

And though Norman swears that the smell is actually pleasant, not everyone agrees. "We've had a few complaints from the neighbors in the summer," admits his wife, Joan Norman. "When our next-door neighbor was pregnant, she said she had to hold her breath all the way down the driveway."

Pub Date: 5/24/98

Copyright © 2019, The Baltimore Sun, a Baltimore Sun Media Group publication | Place an Ad