Conservation Column: Done Right, Farming Can Benefit Both Humans and Birds
Birds help farmers. They control pests, sow seeds, pollinate flowers, and fertilize soils. Unfortunately, the reverse is not true; common agricultural practices do not help birds. Often they have led to devastating bird population declines. The North American Breeding Bird Survey data shows that 74 percent of farmland-associated species decreased between 1966 and 2013. The size of the global human population is large and growing, with a concomitant increase in the numbers of mouths to feed. That means that large swaths of natural habitat are destroyed to make way for agriculture. The remaining patches of native habitat are small and isolated. In addition, the chemicals used to increase crop yields are either interfering with reproduction in birds or killing them outright. Luckily, bird-friendly farming practices do exist.
Growing and buying organic food reduces risks from the many toxins used in conventional farming. Not only do some of these pesticides harm the birds directly (pesticides such as neonicotinoids cause loss of body mass, neurological impairment, and reproductive failure), but they also decimate the insect food base of many birds. Ironically, the loss of birds and beneficial insects, in turn, increases the surplus of crop pests. Low-intensity farming, which utilizes less pesticides and allows for more natural habitat, provides many other benefits, such as soil conservation, improved water quality, and carbon storage.
Several scientific reports have detailed the benefits of planting and maintaining wildflower strips, hedgerows, and other areas of native vegetation on farms. Even though a small area is taken out of crop production, the practice can actually increase crop yield. Plantings support pollinators such as native bees, beneficial insects, and birds. Native bees and some birds improve productivity through their pollination services. Beneficial insects and birds control crop pests. In one recent study, farm-edge habitat that contained native plants supported nearly three times as many bird species as those without, and importantly, reduced the abundance of the most significant insect pests by over 33 percent. Another study noted that planting wildflower strips adjacent to a crop field led to a 40 percent reduction in crop damage due to beetles and other pests.
Protecting riparian or streamside areas, as well as wetlands located on farms, also supports greater biodiversity. Rice farmers in California used to burn the straw residue post harvest. Now they flood their fields, creating temporary wetlands that support migratory and residential birds. It’s another win-win situation. The presence of the birds increases the rate of straw decomposition and creates better planting conditions for the next season.
A 2019 long-term study in Costa Rica measured population declines in 69 out of 112 bird species. On the positive side, coffee plantations that had modest tree cover hosted more types of birds. Farms with an average of about 13 percent tree cover hosted double the number of forest specialist birds compared with plantations with an average of 7 percent tree cover. Other studies have revealed the merits of agroforestry, or shade-grown crops, such as coffee and cocoa. One found 1,216 species of birds using agroforests compared to 303 species using conventional farms. Several surveys of agroforests have documented greater species richness and abundance of individuals, as well as reduced soil erosion, increased carbon sequestration, improved pollination, better pest control, and better connectivity for the many animals that live in forests.
Other sustainable practices include smart water and soil management (such as no-till farming), and moving away from planting mono-crop fields. Many programs, including the US Conservation Reserve Program, will pay landowners to convert highly erodible cropland into wildlife habitat, but the program is underfunded and limited. Stronger government policies in the United States and across the globe are needed to promote more environmentally friendly agricultural practices. Farming can be for the birds as well as the people!