COLUMBIA, Mo. - Many Missourians may have an untapped resource to combat rising food costs right in their own back yard: Families with ponds at least one-quarter acre in size can take a bite out of grocery bills by raising bass and bluegill to eat, said a University of Missouri fisheries expert.

"There are over 500,000 of these small ponds in Missouri," said Rob Hayward, fisheries professor in the MU School of Natural Resources. "There's an opportunity here for people to produce an additional source of protein at relatively low cost."

It's not a new idea, Hayward notes. In the 1930s and '40s, a federal program encouraged the creation of farm ponds as a tool for soil and water conservation and as a food source for cash-strapped Depression-era families.

"The U.S. Soil Conservation Service promoted and facilitated the development of these ponds in rural areas, mostly in the South," Hayward said. "So it's an old concept that I think is coming back, actually."

Hayward is raising bass and bluegill in three ponds at the Prairie Fork Conservation Area in Williamsburg, Mo. Each pond is about 2-3 acres in size. "Our question is, How much can we harvest in a sustainable way year after year?"

Hayward said that existing literature on pond management for bass and bluegill focuses mainly on recreational fishing. "My focus is more about how much food we can harvest annually. My sense is that it is higher than what a lot of people have thought in the past."

Getting the most from the ponds means striking a balance between the predator fish and the prey. Bass need an ample supply of bluegill to eat, while bluegill need enough bass to keep their numbers in check. "The bass keep the bluegill populations at a low enough level that they're not overshooting their own food supply," Hayward said.

In one of the ponds, Hayward added a second species of prey fish, gizzard shad. "Smaller bass really jump in growth rates with these shad," he said. "The downside is that if the bass don't control the shad by eating enough of them, they can get too large for the bass to eat and take over the pond."

Hayward emphasizes that he is not employing intensive aquaculture techniques used by commercial fisheries. While intensive aquaculture boosts production, it also involves considerable cost, effort and risk.

By contrast, Hayward's study, funded by the Prairie Fork Trust, is relatively small-scale, with much of the field work carried out by a single graduate student, Brandon Hanquist, who was assisted by Tony Overmann, an undergraduate fisheries and wildlife student.

"This is under what we call 'extensive aquaculture.' We're not adding any food. We might do a little bit of fertilizing now and then. Basically, these are natural production levels for these ponds," Hayward said.

"This year my aim is to harvest 20 percent of the bass and bluegill biomass in these three ponds," Hayward said. "That would equate to a substantial amount of fish flesh that people could put in the freezer and eat. We plan to do that for three more years to see how sustainable that level would be."

For the ponds to work as a sustainable food source, landowners need to be able to manage them year after year without having to restock frequently, add large amounts of nutrients or provide supplemental food. "There's no rocket science here," Hayward said. "But it's not a done deal trying to manage these ponds. It requires some knowledge and a little bit of luck."

Hayward hopes his study will add to that knowledge and reduce the role of pure luck. He plans to publish his findings in peer-reviewed papers and short articles.

"I think this is an opportunity that is probably going to be looked at quite favorably as food prices continue to go up," he said.