Adapted from audubon.org/news/what-do-birds-do-us By Barry Yeoman, April 8, 2013
Have you ever thought about all the ways that birds are beneficial to us and our environment? The collective term for the many ways birds (and other animals, plants, and landscapes) support and improve human life is “ecosystem services.” Pest control, public health, seed dispersal, ecotourism, environmental monitoring—these are some of the ways birds benefit humans. There are many others, including:
Improved Mental Health for Humans
Studies have shown spending time in nature improves both cognition and mental health. “Birding is such a gateway to nature,” says Kimberly Kaufman, executive director of the Black Swap Bird Observatory in Ohio. “It gets people outside—away from the computer, away from the television.” It exposes us to fresh air and lifts our spirits. “We’ve been using the phrase ecotherapy, ” she says. “Let’s face it: We can all use more joy in our lives.”
Perhaps the least sexy service birds provide is eating dead animals. “We’ve got an enormous amount of roadkill produced on our highways in the United States,” says Travis DeVault, a research wildlife biologist with the U.S. Department of Agriculture. “I don’t think anyone knows what that would look like if vultures weren’t around to clean up a big portion.”
In 1914, Pennsylvania’s health commissioner, Samuel Dixon, declared “the duck is one of the greatest known enemies of the mosquito, and therefore of yellow fever and malaria.” Dixon ran an experiment involving two ponds—one stocked with mallards and the other with goldfish—and discovered that the ducks ate mosquito larvae far more “ravenously” than the fish did.
In the high mountains of the American West, there’s a tree called the whitebark pine. Its large seeds feed grizzlies and black bears, and because the pines grow all the way up to the treeline, they are effective at protecting drinking-water supplies. The trees’ roots also hold the soil in place, preventing erosion, which also reduces the danger of avalanche. The tree’s seeds are dispersed by just one bird: the Clark’s nutcracker. The nutcracker’s long, sturdy bill opens the pinecones to pluck out the seeds, which it eats or stores inside its throat. It then buries the uneaten seeds at the depth and location the trees often need to reproduce.
Many of us have read Rachel Carson’s 1962 book Silent Spring, which chronicled the lethal effects of the insecticide DDT. While Carson, a biologist, documented the havoc wreaked throughout the food chain, her book is best remembered for its account of how the fight against Dutch elm disease poisoned entire populations of robins as well as 90 other bird species. Carson’s robins—along with the thinning egg shells of American bald eagles exposed to pesticides—signaled to many Americans that birds could serve as “winged sentinels” of environmental degradation.
Scientists routinely use birds to gauge the health of ecosystems—and not just for purely biological reasons. Birds often meet the technical criteria, such as sensitivity to environmental changes. Tree swallows have been used to study the impact of a wide range of toxins: PCBs in the Great Lakes and Hudson River, pulp-mill effluent in Western Canada, petroleum in Wyoming’s North Platte River, and metals in New Jersey. Their work has shown that contaminants that land in aquatic sediment don’t remain there; they work their way up the terrestrial chain.
Pollination is often in the realm of bees, bugs, and butterflies. More than 900 bird species worldwide pollinate, too, and their sophisticated sense of geography suits them well to the task. The durian munjit, a wild fruit that is collected and eaten in northern Borneo, relies exclusively on spiderhunters, members of the sunbird family. A passerine called the Canarian chiffchaff pollinates the Canary bell-flower, an ornamental plant with edible fruit that grows on Spain’s Canary Islands. (It was cultivated in the royal garden of England’s Hampton Court Palace as early as 1696.)
Birds possess skills that historically made them useful to militaries. During World War I, pheasants detected oncoming hostile aircraft at long distances and “gave the alarm by their insistent cries,” says one account; canaries, of course, sensed poison gas; gulls followed submarines in search of garbage. Carrier pigeons successfully navigated through shellfire (and past bullets aimed at them). They transported messages that helped the Allies capture German submarines, and that saved the crews of downed seaplanes and a sunken minesweeper. It turns out birds aren’t just useful. They’re bonafide heroes.