They are currently taste-testing a byproduct of prickly pear cactus foods in pellet, biscuit, wafer and zoo-log form. "The idea is appealing to us in several ways," says General Curator Scott Barton. "The cactus pulp is high in fiber and low in calories, the kind of thing that a lot of these animals, like tortoises, giraffes and elephants, might welcome as a supplement to their regular zoo feed."
When you're responsible for staving off hunger pangs among the hundreds of animals, from little critters with small appetites to bears and elephants with gargantuan tastes, locally produced new menu additions are welcome.
"We feed up to 500 animals a day, most of them twice per day, at a cost of $10,000 a month," says Barton. "Our food volume depends on the animal, and the type of food ranges from fish for certain animals, a variety of meats, fruit and produce and dried foods like hay and grains."
The cactus concoction is the brainchild of the zoo's consulting nutritionist, Dr. Howard Fredericks, and Cheri Romanoski, owner of Cheri's Desert Harvest, who has spent the last 20 years producing preserves made from the fruits of the desert. Her company picks and processes prickly pear cactus fruit--more than 60,000 pounds annually--into natural jellies, marmalades, syrups and candy. Until recently, the leftover cactus pulp had little use, and was donated to local ranchers to use as field mulch or dust control from cattle and horses.
Romanoski didn't like the fact that few opportunities existed to beneficially recycle the tons of byproduct. She began drying the pulp and formulating an idea of turning it into compressed logs for fireplaces.
All that changed when Fredericks stopped in for a jar of jelly. "We started talking about what to do with the wet residue, raw material that is high in protein, fiber, vitamins and minerals," she says. The concept was to find a use for the 18,000 pounds of pulpy pressed mash and not just throw it away. They think they have done so, depending on the outcome of evaluations by resident animals at the zoo in Tucson and two zoos in the Phoenix area.
"I don't think the animals have immediately put it at the top of their menu choices," says Barton after a couple of months of testing. "Some of our animals are a bit spoiled, and, like humans, getting used to a new diet item takes some time." That might explain why Tucson's giraffe population briefly mouthed the cactus biscuit samples before spitting them back out--without apology. "It's not an indictment of the product," says Fredericks. "They'll catch on. When we first started feeding these animals rye crisp, they wouldn't eat them, either. They're fussy. But zoo animals are a good test population, because if you can get pampered animals in captivity to eat a new product, everybody else will, too."
Although the giraffes remained aloof to the new food samples, lumbering tortoises slowly masticated the treats with apparent approval. "To date, we're seeing that all of the ungulates, hoof stock like zebras and antelope, like the product," says Fredericks. In the mandrill cage, DJ (Danny Junior) displayed his fangs when zookeeper Alisha Brewer asked him to. In return, the cooperative primate was rewarded with cactus biscuits. Repeatedly. With no rejection.
Barton chooses his words carefully in evaluating the cactus fodder. "Because we're connected to the city of Tucson, we can't endorse new products. But we're open to new ideas and are willing to be involved in experiments of a possible new resource. At this point, I think it's fair to say that we're definitely in the process of tinkering with the formula."
Romanoski is patient. "We're looking to find the optimum combination, and I'll keep going back to square one until we do."
Fredericks echoes her determination on that. "We just need to find the right formulation," he says. "The fact that Native Americans have been consuming prickly pear cactus pods for centuries suggests they're probably not bad for you. And while they won't make up a large part of an animal's diet, because they're seasonal in production, I see nothing in our initial scanning to suggest a certain number of biscuits a day would be detrimental. Obesity is a major concern with captive animals, but this product shouldn't contribute to that, because it would be used as a food supplement, not the main meal."
The nutritionist and the baker will keep at their trial-and-error efforts until they come up with a popular blue-plate special. "We'll get there," says Romanoski. "And when we do, not only will we be producing a product nutritionally beneficial to the animals; we'll also demonstrate the ingenuity of local companies that use local resources and recycle them in a most effective way."
Another developmental direction involves packaging the product for the pet industry. "Prickly pear is an anti-inflammatory," Romanoski says, "so we're looking at this as a natural ingredient pet owners could introduce to their animals to reduce joint inflammation."
Says Fredericks: "I want the public to see that we're taking a product native to the area, one that has been tossed out in the past, and turning it into a good product from a nutritional and ecological standpoint. Not only are we finding a second use for the prickly pear cactus pulp in zoo biscuit form; when the resultant manure goes into the fertilizer pile, that will be a third use. This is recycling at its finest."