International Migratory Bird Treaty Act (IMBTA)

(Adapted from and

Lacey Act (1900)

In the late 1800s, the hunting and shipping of birds to restaurants (to augment their menus) and of birds’ feathers the millinery trade (to adorn ladies’ hats) took a toll on the populations of many bird species. The numbers of Passenger Pigeons, Eskimo Curlews, shorebirds, egrets and many other colonially nesting birds had been decimated across the country. The Lacey Act (1900) prohibited game (including birds) that had been taken illegally in one state from being shipped across state lines contrary to the laws of the state where it had been taken. The law was replaced by the Weeks-McClean Law of 1913.

Weeks-McClean Law (1913)

The Weeks-McClean Law (1913) was intended to stop commercial hunting of game (including birds) and the illegal shipment of migratory birds from one state to another.  The Act states that birds “…shall hereafter be deemed to be within the custody and protection of the Government of the United States, and shall not be destroyed or taken contrary to regulations hereinafter provided therefore”.  The law was replaced by the Migratory Bird Treaty Act of 1918.

Migratory Bird Treaty Act of 1918

The Migratory Bird Treaty Act of 1918 decreed that all migratory birds and their parts (including eggs, nests, and feathers) were fully protected by law. The Act is the domestic law that implements the four conventions (or treaties) between the United States and Canada, Japan, Mexico and Russia for the protection of our migratory bird resources. The four conventions protect the birds that occur in both countries at some time during their annual cycle.

The original 1918 statute implemented the 1916 convention between the U.S. and Great Britain (acting for Canada) for the protection of migratory birds. Later amendments to the Act implemented migratory bird conventions with Japan, Mexico, and the Soviet Union (now Russia).

A list of birds protected by the Migratory Bird Treaty Act is available at (updated 2020)

Specific provisions included in the statute are:

  • Establishment of a Federal prohibition, unless permitted by regulations, to "pursue, hunt, take, capture, kill, attempt to take, capture or kill, possess, offer for sale, sell, offer to purchase, purchase, deliver for shipment, ship, cause to be shipped, deliver for transportation, transport, cause to be transported, carry, or cause to be carried by any means whatever, receive for shipment, transportation or carriage, or export, at any time, or in any manner, any migratory bird, included in the terms of this Convention . . . for the protection of migratory birds . . . or any part, nest, or egg of any such bird." (16 U.S.C. 703)
  • Authority for the Secretary of the Interior to determine, periodically, when, consistent with the Conventions, "hunting, taking, capture, killing, possession, sale, purchase, shipment, transportation, carriage, or export of any . . .bird, or any part, nest or egg" could be undertaken and to adopt regulations for this purpose. These determinations are to be made based on "due regard to the zones of temperature and to the distribution, abundance, economic value, breeding habits, and times of migratory flight." (16 U.S.C. 704)
  • A decree that domestic interstate and international transportation of migratory birds which are taken in violation of this law is unlawful, as well as importation of any migratory birds which are taken in violation of Canadian laws. (16 U.S.C. 705)
  • Authority for Interior officials to enforce the provisions of this law, including seizure of birds illegally taken which can be forfeited to the U.S. and disposed of as directed by the courts. (16 U.S.C. 706)
  • Establishment of fines for violation of this law, including misdemeanor charges. (16 U.S.C. 707)
  • Authority for States to enact and implement laws or regulations to allow for greater protection of migratory birds, provided that such laws are consistent with the respective Conventions and that open seasons do not extend beyond those established at the national level. (16 U.S.C. 708)
  • A repeal of all laws inconsistent with the provisions of this Act. (16 U.S.C. 710)
  • Authority for the continued breeding and sale of migratory game birds on farms and preserves for the purpose of increasing the food supply. (16 U.S.C. 711)

Subsequent amendments to the 1918 Act include:

  • The 1936 statute implemented the Convention between the U.S. and Mexico for the Protection of Migratory Birds and Game Mammals. Migratory bird import and export restrictions between Mexico and the U.S. were also authorized, and in issuing any regulations to implement this section, the Secretary of Agriculture was required to consider U.S. laws forbidding importation of certain mammals injurious to agricultural and horticultural interests. Monies for the Secretary of Agriculture to implement these provisions were also authorized.
  • The 1960 statute (P.L. 86-732) amended the MBTA by altering earlier penalty provisions. The new provisions stipulated that violations of this Act would constitute a misdemeanor and conviction would result in a fine of not more than $500 or imprisonment of not more than six months. Activities aimed at selling migratory birds in violation of this law would be subject to fine of not more than $2000 and imprisonment could not exceed two years. Guilty offenses would constitute a felony. Equipment used for sale purchases was authorized to be seized and held, by the Secretary of the Interior, pending prosecution, and, upon conviction, be treated as a penalty.


  • Section 10 of the 1969 amendments to the Lacey Act (P.L. 91-135) repealed the provisions of the MBTA prohibiting the shipment of wild game mammals or parts to and from the U.S. or Mexico unless permitted by the Secretary of the Interior. The definition of "wildlife" under these amendments does not include migratory birds, however, which are protected under the MBTA.


  • The 1974 statute (P.L. 93-300) amended the MBTA to include the provisions of the 1972 Convention between the U.S. and Japan for the Protection of Migratory Birds and Birds in Danger of Extinction. This law also amended the title of the MBTA to read: "An Act to give effect to the conventions between the U.S. and other nations for the protection of migratory birds, birds in danger of extinction, game mammals, and their environment."
  • Section 3(h) of the Fish and Wildlife Improvement Act of 1978 (P.L. 95-616) amended the MBTA to authorize forfeiture to the U.S. of birds and their parts illegally taken, for disposal by the Secretary of the Interior as he deems appropriate. These amendments also authorized the Secretary to issue regulations to permit Alaskan natives to take migratory birds for their subsistence needs during established seasons. The Secretary was required to consider the related migratory bird conventions with Great Britain, Mexico, Japan, and the Soviet Union in establishing these regulations and to establish seasons to provide for the preservation and maintenance of migratory bird stocks.


  • Public Law 95-616 also ratified a treaty with the Soviet Union specifying that both nations will take measures to protect identified ecosystems of special importance to migratory birds against pollution, detrimental alterations, and other environmental degradations. (See entry for the Convention Between the United States of America and the Union of Soviet Socialist Republics Concerning the Conservation of Migratory Birds and Their Environment; T.I.A.S. 9073; signed on November 19, 1976, and approved by the Senate on July 12, 1978; 92 Stat. 3110.)
  • Public Law 99-645, the 1986 Emergency Wetlands Resources Act, amended the Act to require that felony violations under the MBTA must be "knowingly" committed.


  • P.L. 105-312, Migratory Bird Treaty Reform Act of 1998, amended the law to make it unlawful to take migratory game birds by the aid of bait if the person knows or reasonably should know that the area is baited. This provision eliminates the "strict liability" standard that was used to enforce Federal baiting regulations and replaces it with a "know or should have known" standard. These amendments also make it unlawful to place or direct the placement of bait on or adjacent to an area for the purpose of taking or attempting to take migratory game birds, and makes these violations punishable under title 18 United States Code, (with fines up to $100,000 for individuals and $200,000 for organizations), imprisonment for not more than 1 year, or both. The new amendments require the Secretary of Interior to submit to the Senate Committee on Environment and Public Works and the House Committee on Resources a report analyzing the effect of these amendments and the practice of baiting on migratory bird conservation and law enforcement. The report to Congress is due no later than five years after enactment of the new law.
  • P.L. 105-312 also amends the law to allow the fine for misdemeanor convictions under the Migratory Bird Treaty Act to be up to $15,000 rather than $5000.

Migratory Bird Treaty Act of 1918 (16 U.S.C. 703-712; Ch. 128; July 13, 1918; 40 Stat. 755) as amended by: Chapter 634; June 20, 1936; 49 Stat. 1556; P.L. 86-732; September 8, 1960; 74 Stat. 866; P.L. 90-578; October 17, 1968; 82 Stat. 1118; P.L. 91-135; December 5, 1969; 83 Stat. 282; P.L. 93-300; June 1, 1974; 88 Stat. 190; P.L. 95-616; November 8, 1978; 92 Stat. 3111; P.L. 99-645; November 10, 1986; 100 Stat. 3590 and P.L. 105-312; October 30, 1998; 112 Stat. 2956
The United States is party to other international treaties that provide special protection to birds including:

  • The Ramsar Convention or the Convention on Wetlands of International Importance Especially as Waterfowl Habitats.
  • The Antarctic Treaty, which is designed to protect the native birds, mammals, and plants of the Antarctic.
  • CITES or the Convention on International Trade in Endangered Species of Wild Fauna and Flora.
  • The Pan American Convention or the Convention on Nature Protection and Wildlife Preservation in the Western Hemisphere.

The Duck Stamp Act, Wetlands Loan Act, Emergency Wetlands Resources Act, Migratory Bird Conservation Act, Waterfowl Depredations Prevention Act, Fish and Wildlife Conservation Act, Wild Bird Conservation Act and North American Wetlands Conservation Act also serve to protect birds.

Piping Plover Chick
Piping Plover Chick
Interior Least Tern in Flight
Interior Least Tern in Fligh
Piping Plover in water
Piping Plover in water