10 Reasons to Be Thankful for Birds
Whether you’re eating turkey or tofurky this Thanksgiving, raise a glass to the many ways in which wild birds enrich our lives—and in fact support our very existence.
1. They provide pest control.
Modern history is filled with stories of birds saving potato fields, fruit orchards, and cranberry bogs from insect devastation. Now researchers are studying the phenomenon more formally, trying to quantify birds' value as living pest controllers.
Consider the case of the coffee berry borer. These tiny insects invade individual coffee berries and spend almost their entire lives inside, making those beans unsellable. There are no safe pesticides that kill the insects, and attempts to control them with parasitic wasps have shown, at best, limited success.
But black-throated blue warblers, American redstarts, and other birds feast on the borers when the insects are first drilling into the berries. A researcher at one site in Jamaica's Blue Mountains calculated the birds' pest-control value at $125 per acre, or nearly one-eighth of the total crop value of $1,044 per acre.
In the Netherlands insect-eating birds protect apple orchards, and in Missouri's Ozark Mountains they safeguard white oaks, whose lumber is highly sought by furniture makers. Birds even reduce pests at organic wineries.
2. They're money makers.
Birds stimulate economies just by being the beautiful, fascinating creatures they are. In an economic analysis released in 2009, the U.S. Fish and Wildlife Service calculated that, based on a 2006 survey, birders spend $12 billion annually on travel and an additional $24 billion on equipment including binoculars, camping gear, and nest boxes. That money ripples out, generating $82 billion in economic output, employing 671,000 people, and enriching state and federal governments by $10 billion.
You need only visit Ohio's Maggee Marsh to see that ripple effect in action. This 2,000-acre wildlife refuge on Lake Erie is a stopover for neotropical migrants, which rest and refuel before crossing the lake. With such avian abundance, the marsh attracts more than 100,000 birders a year. One researcher calculated that in 2011 Magee Marsh and five other Lake Erie birdwatching areas in Ohio collectively generated $26 million in spending and created 283 jobs.
3. They clean up.
Perhaps the least sexy service birds provide is eating dead bodies. They clean up enormous amounts of roadkill all over the world. Unfortunately, vulture populations everywhere have suffered major declines. In many cases, the cause can be traced to indirect poisonings that are the result of drugs given to the animals the vultures feed on. When vulture numbers plunged in India, feral dogs took over carcass disposal. This led to a growing canine population, which meant more fatal dog attacks, as well as an increase in rabies and bites.
Economist Anil Markandya estimates that there have been almost 40 million additional dog bites in India between 2002 and 2006, resulting in about 48,000 extra deaths. He calculates that the vulture-dog connection alone produced human health costs totaling $34 billion over 14 years.
4. They spread seeds.
In the high mountains of the American West, the future of a tree called the whitebark pine hangs in the beak of a particular bird. The tree's seeds are dispersed only by the Clark's nutcracker, a black-and-white-winged cousin to the crow. 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 that the trees often need to reproduce. Without the nutcracker, it's unlikely that the whitebark pine could sustain itself.
Researchers with the U.S. Forest Service have done some experiments that help quantify the value of the nutcracker's dispersal service. They figure its worth at between $800 and $1,000 per acre, based on what it would cost to plant the pines by hand. Multiply that by about 14.3 million acres of whitebark pine forest, and you get savings of more than $11 billion in the United States alone.
5. They announce danger.
Most of us are familiar with Silent Spring, Rachel Carson's 1962 book, which chronicled the lethal effects of the DDT. Carson's robins--along with bald eagles exposed to the pesticides--signaled to many Americans that birds could serve as "winged sentinels" of environmental degradation. More than 50 years later scientists routinely use birds to gauge the health of ecosystems--and not just for purely biological reasons.
Tree swallows are providing insight on the impact of a wide range of 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. Likewise, scientists have been monitoring the health of common loons in New York's Adirondack Park to understand the impact of atmospheric mercury from coal-burning power plants and incinerators. By measuring the loons' breeding success and correlating it to mercury contamination, scientists have been able to provide evidence for the need to stringently regulate mercury and acidic emissions on national and global scales.
6. They pollinate.
Pollination is the recognized realm of bees, bugs, and butterflies. But 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.