Agriculture Impacts on Hummingbirds
Continuous or year-round farming practices can result in the loss or fragmentation of natural habitats, both terrestrial and wetland, which causes reduced availability of food resources, increased exposure to pesticides and other agrochemicals, and disturbance from farming activities, such as machinery noise and land clearance. These factors can disrupt bird nesting, foraging, and migration patterns, leading to declines in bird populations, changes in species composition, and overall biodiversity loss.
As with songbirds, intensification of farming likely means a loss of food, shelter, nesting, and feeding habitats for hummingbirds. For example, hummingbirds depend on flowers for nectar, which are generally lost when intensification of farming occurs across landscapes. However, the specific impacts of intensified agriculture on hummingbirds are largely undocumented.
Research comparing shade-grown and sun-grown coffee provides insight into techniques that can enhance agricultural practices to benefit hummingbirds (Barney 2019). While hummingbirds are not the primary pollinators of this product, there is evidence that many species forage on the flowers or on the flowers of trees found in the vicinity or within plantations that have at least some vegetative structure beyond coffee plants (Barney 2019; Morrison and Mendenhall 2020). Simple measurements of habitat characteristics indicate that on farms with more floral resources, hummingbird density is higher. (Reference) As management intensifies, the density of hummingbirds declines. In North America, there is also evidence from studies on diet that hummingbirds potentially pollinate in flowering orchards and nut farms, but details about the extent of use of these crops is not well-documented.