The Migratory Bird Treaty Act was one of Audubon’s first major victories. Put simply the MBTA protects nearly all native birds and their nests and eggs from humans. It also recognizes that birds migrate and even relatively local bird populations don’t acknowledge state borders. The treaty emerged after several decades of activism by the newly emerging Audubon Society and others amidst the decimation of U.S. bird populations for sport and fashion.

By the end of the 19th Century Labrador Ducks and Great Auks were extinct and followed soon after by Passenger Pigeons, Carolina Parakeets and Heath Hens. The Snowy Egret was hunted almost to extinction as the long plumes grown for breeding season became prized fashion accessories. The egret and many other species became indiscriminate victims of profit.

In response to the extinction and near extinction of many birds, the late 1800s and early 1900s saw a growing conservation movement with the formation of the National Audubon Society, the first ornithological societies, the first modern bird banding program, and the establishment of the annual Christmas Bird Count began. These often overlapping groups worked to pass legislation to halt the decimation of U.S. bird populations. The early 1900s saw a series of state and federal laws and court cases aiming to protect birds and wildlife –The Lacey Act, The Weeks-McLean Law, and the Underwood Tariff Act–all aimed to prevent the killing of birds for private gain by providing federal protections and penalties. 

In 1916, a Treaty for the Protection of Migratory Birds was signed between the U.S. and Great Britain (on behalf of Canada). The goal of the treaty was to “assure the preservation of species either harmless or beneficial to man.” The treaty established which species would be covered, made the first distinction between game, non-game and insectivorous birds, established closed dates for hunting game birds, established the “take” of birds for scientific or propagating purposes, prohibited the export of birds and eggs except for scientific and propagation purposes and established permits to control birds that become agricultural pests.

In 1918 the U.S. Congress implemented the new treaty with the passage the Migratory Bird Treaty Act which officially makes it a crime to “pursue, hunt, take, capture, kill,” or “sell” a migratory bird or any of its parts, including nests, eggs, and feathers. The passage of this federal act eliminated the need to monitor multiple state laws.

Since its passage nearly a century ago the act has: survived a challenge in the supreme court; expanded its range through additional treaties with Mexico, Japan, and Russia (Soviet Union); expanded the range of birds covered and expanded penalties. The MBTA now covers more than 1,000 species, including eagles, hawks, owls and corvids and almost every native species in the U.S.  Here’s a full list of species covered by the MBTA.

In this century the MBTA gained strength in 2000 when a federal appeals court held that private citizens (such as conservation groups) may sue the government over alleged violations of the act.  However, they cannot sue out-of-compliance private companies under the act.  Before leaving office, President Clinton ordered relevant federal agencies to take migratory bird conservation into account as part of their regular decision making.

The 21st century has also seen new challenges in keeping birds safe.  Relatively new problems such as wind turbines, communications towers, oil pits, and high-tension power lines are faced by birds today.  Enforcement of the MBTA against some of these problems tends to be sporadic.  However, in 2013 the Department of Justice, for the first time, enforced the MBTA against a wind farm operator, imposing $1 million in penalties for the killing of Golden Eagles and other protected birds at two sites in Wyoming. Shortly after that it followed up with $2.5 million in penalties against a second Wyoming wind farm operator.

To this day, the Migratory Bird Treaty Act remains the primary tool for protecting non-endangered species.  The law continues to evolve as new and changing threats to birds present themselves.