What is the big deal with wildlife and farmland? It has to do with what we want for our farms, communities and environment. Some species are disappearing, and agriculture is blamed as the culprit. That's not really a new situation, as agriculture has always taken a natural environment and changed it to one managed by people. Some species flourish in the human-influenced habitat, while others don't.
That's the first lesson: everything is habitat. Habitat is where critters live. It provides all the needs of a species: food, shelter, space, and water. All creatures need certain ranges of light, heat, water, and protective cover to sustain themselves. The ranges tolerated by blue jays, for example, are different than those tolerated by Canada geese. Which do we want? Both are wildlife. Both are desirable. But we can't have maximum numbers of each in the same space.
That's lesson two: diversity of wildlife requires diverse habitats. Agriculture has reduced the diversity of habitats by creating monocultures - large areas with only one plant species, such as cornfields. In a monoculture there is only one plant for insects, birds, or animals to eat. There is only one height of vegetation to sit on or hide in. The soil's surface has a uniform moistness, temperature range, and cover. Only wildlife species that can tolerate those particular conditions will live there. Some may do very well, such as corn borers, while others may only visit, such as whitetail deer. The biological diversity (number of animal or plant species) of a typical monoculture field is very low.
Dennis Avery, author of Saving the World with Pesticides and Plastic, claims that agriculture "destroys" land for wildlife. He believes that we must maximize agricultural production on some land and save other land exclusively for wildlife. But farms don't have to provide only one set of living conditions. Proponents of sustainable agriculture think that both wildlife and farmers can use the same land.
Ann Robinson, in the 1991 Walton League publication "Sustainable Agriculture: A Brighter Outlook for Fish and Wildlife," reports that sustainable farmers often farm smaller fields and use more crops in their rotations than conventional farmers. They recognize the benefits of birds, insects, and even plants sometimes called weeds. Livestock, which add to diversity, are often included in sustainable farming systems. Their manure feeds birds and insects. Livestock necessitate the production or delivery of foods that wouldn't otherwise be part of the farm. Sustainable farmers often express considerable concern about soil erosion, and sustainable farming practices that reduce erosion are good for fish.
So if it's good to stop erosion, then no-till farming must be great, right? That depends on the chemicals needed to farm without mechanically killing weeds. "Paraquat, a herbicide frequently used in no-till farming, is very toxic to some birds and mammals" says Robinson. "Several herbicides have been shown to harm fish. The synergistic effects that may happen when several chemicals are combined can make these products more harmful."
Those synergistic (increased and/or changed) effects include what some scientists call "endocrine disruption." Trace amounts of pesticides or their residues apparently act like animal hormones and disrupt normal body functions like growth and reproduction. Such side effects of pesticide use could wreak havoc on the health of wild animals, domestic livestock, and people.
So, what do we want? Holistic Resource Management practitioners use a planning process that starts with describing their goal: quality of life, production to support it, and the environment to allow that production. If we want wildlife, we need only to plan for it and to put that plan into action.
Many HRM farmers and ranchers have explicit plans to include wildlife on their land. They can point to the economic gains they expect from working with natural processes, instead of against them. Their plans can include simple ideas like scheduling grazing or haying dates to avoid critical nesting sites. A more complex plan might include grazing to influence shrub density and grass regrowth on deer winter range.
University of Missouri agricultural economist John Ikerd agrees with the HRM approach for including wildlife on farms. He believes that, "Success...is measured against the goal of sustainable human progress — balanced economic, ecologic, and social progress." Each farm family can choose its own balance point, and can create a farm plan to reach that point. The resulting mix of farm profits, a healthy farm environment, and a supportive community can easily include farm wildlife.
Wyatt Fraas, Center for Rural Affairs
Nebraska Sustainable Agriculture Society: Home Features
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