Oklahoma Bar Journal
The Migratory Bird Treaty Act at More Than a Century: A Bird's-Eye View of the History, Evolution, and Future of Federal Migratory Bird Protection
By Charis Ward
The Migratory Bird Treaty Act (MBTA) is among the oldest wildlife protection statutes in the United States.[i] Enacted in 1918 to implement an international treaty, the statute continues to influence environmental compliance, project development, and wildlife conservation.[ii] For Oklahoma practitioners, the MBTA remains particularly relevant because Oklahoma lies within the Central Flyway and because many industries operating within the state regularly intersect with migratory bird habitat.[iii]
Although the statute's core language has remained largely unchanged for more than a century, the world around it has changed dramatically. Modern questions frequently involve infrastructure, energy development, building collisions, habitat alteration, and the relationship between conservation and economic activity.
Birds provide ecological, economic, and cultural benefits.[iv] They contribute to ecosystem health through pollination, seed dispersal, and insect control.[v] Wildlife observation and bird-related recreation contribute significant economic value. Seasonal migrations also remain one of the most visible connections between people and the natural environment.[vi]
Understanding these benefits helps explain why Congress elected to protect migratory birds through an international treaty framework and why legal questions concerning migratory birds continue to attract attention today.
HISTORICAL BACKGROUND AND LEGAL FRAMEWORK
During the late 19th and early 20th centuries, bird populations in North America experienced substantial declines due to market hunting and the feather trade.[vii] Because migratory birds routinely crossed state boundaries, state regulation proved insufficient.[viii] The U.S. therefore entered into the 1916 Convention for the Protection of Migratory Birds, and Congress implemented that treaty through the MBTA in 1918.[ix] The Supreme Court upheld the statute in Missouri v. Holland, establishing one of the most important precedents concerning federal treaty power and wildlife conservation.[x]
The MBTA broadly prohibits the unauthorized pursuit, capture, killing, possession, transportation, or sale of protected migratory birds.[xi] The U.S. Fish and Wildlife Service administers the statute through regulations and permitting programs.[xii] Violations may result in criminal penalties and, in some circumstances, substantial consequences for regulated entities.[xiii]
WHY BIRD POPULATION TRENDS MATTER TO THE LAW
Recent studies have documented significant declines in many North American bird populations.[xiv] These trends do not alter the text of the MBTA, but they help explain why questions concerning migratory bird protection continue to generate litigation, regulatory attention, and legislative interest. Modern debates often reflect efforts to determine how a century-old statute should function in a rapidly changing world.
ENFORCEMENT AUTHORITY AND SIGNIFICANT JUDICIAL DECISIONS
Missouri v. Holland remains foundational.[xv] Later decisions, including United States v. FMC Corp. and United States v. Apollo Energies, Inc., addressed whether liability may arise when industrial activities foreseeably result in bird mortality.[xvi] These cases helped shape the modern incidental-take debate and continue to influence legal analysis.
THE INCIDENTAL TAKE DEBATE
One of the most significant controversies under the MBTA concerns incidental take, meaning unintentional injury or death resulting from otherwise lawful activities.[xvii] For many years, federal regulators generally interpreted the MBTA as applying to at least some forms of incidental take, particularly where bird mortality was foreseeable and avoidable. Enforcement efforts commonly focused on oil pits, wastewater ponds, power lines, communication towers, and other structures known to cause avian mortality. Courts reached differing conclusions, producing uncertainty for regulators and industry alike.
The most recent chapter in the incidental take debate occurred in April 2025 when the Department of the Interior issued Solicitor’s Opinion M-37085.[xviii] The opinion revoked Solicitor’s Opinion M-37065 and directed department personnel to treat Solicitor’s Opinion M-37050 as the governing interpretation of the Migratory Bird Treaty Act in most jurisdictions.[xix]
The practical significance of this development is substantial. Solicitor’s Opinion M-37050 concludes that the MBTA prohibits only actions intentionally directed at migratory birds and does not apply to incidental bird mortality resulting from otherwise lawful activities. Under that interpretation, the accidental death of birds at industrial facilities, wind energy projects, communication towers, transmission lines, or commercial buildings generally falls outside the statute’s scope unless the conduct is specifically directed toward birds.
At first glance, the reinstatement may appear to provide greater regulatory certainty for industry. Companies evaluating potential MBTA exposure can reasonably view the department’s current position as reducing the likelihood of federal enforcement actions based solely upon incidental bird mortality. Project developers and operators may therefore encounter fewer compliance uncertainties than existed under prior agency interpretations.
The legal landscape, however, remains more complicated than the department’s policy statement alone might suggest. A significant limitation arises from the decision of the United States District Court for the Southern District of New York in Natural Resources Defense Council v. U.S. Department of the Interior.[xx] There, the court vacated Solicitor’s Opinion M-37050, concluding that the interpretation conflicted with the text and history of the MBTA.[xxi] The court reasoned that the statute’s broad prohibitions against killing protected birds were not necessarily limited to conduct specifically directed at birds.[xxii]
Although the department’s 2025 opinion reinstates M-37050 as agency policy, it expressly recognizes the continuing effect of the Southern District of New York’s decision within that jurisdiction.[xxiii] As a result, the federal government now operates under a framework in which the department’s nationwide policy favors a narrow interpretation of the MBTA while a significant federal court decision reaches a contrary conclusion.
This divergence raises several questions that may ultimately require resolution by Congress or the federal appellate courts. First, the continuing disagreement highlights a fundamental issue of statutory interpretation. The MBTA was enacted in 1918 to address widespread commercial exploitation of migratory birds. Many of the threats facing birds today arise from activities associated with modern development. Courts and policymakers therefore continue to wrestle with whether statutory language drafted more than a century ago should be read narrowly according to its original context or broadly enough to address contemporary sources of avian mortality. Second, the controversy exposes the limits of regulating wildlife conservation through shifting agency interpretations. Since 2017, federal policy regarding incidental take has changed multiple times. The resulting uncertainty affects not only regulated entities but also conservation planning and long-term infrastructure investment. Regardless of which interpretation ultimately prevails, a stable and predictable framework may be more valuable than continued oscillation between competing administrative positions.
The ongoing dispute over incidental take therefore reflects more than a technical disagreement regarding statutory construction. It illustrates a broader challenge facing the law: how to apply long-standing statutes to modern economic development activities while remaining faithful to congressional intent.
For attorneys and judges confronting future MBTA disputes, the issue may not simply be whether incidental take is prohibited. The more enduring question may be whether existing legal frameworks adequately address the challenges that migratory birds face in the 21st century.
OKLAHOMA AND THE CENTRAL FLYWAY
Oklahoma occupies a unique position within the Central Flyway.[xxiv] Millions of birds migrate through the region annually.[xxv] Protected species commonly encountered in Oklahoma include mallards, Canada geese, red-tailed hawk, great blue heron, Northern cardinal, scissor-tailed flycatcher, and numerous songbirds.[xxvi] Energy development, transmission infrastructure, transportation projects, agriculture, and commercial development may all intersect with migratory bird habitat, making awareness of MBTA-related issues useful for Oklahoma practitioners.[xxvii]
BUILDINGS, INFRASTRUCTURE, AND BIRD-FRIENDLY DESIGN
Bird collisions with buildings are increasingly recognized as a significant source of avian mortality.[xxviii] In response, some jurisdictions have adopted bird-friendly design standards addressing glass treatments, lighting management, and building design features.[xxix]
Bird-friendly approaches also appear in voluntary standards, professional guidance, and public-building programs.[xxx] These initiatives demonstrate that wildlife considerations may be incorporated into planning and design long before legal disputes arise.
THE LACEY ACT
The Lacey Act predates the MBTA and functions principally as a commerce-based enforcement statute.[xxxi] Rather than creating comprehensive species protections of its own, it strengthens other wildlife laws by prohibiting trafficking in wildlife taken in violation of federal, state, tribal, or foreign law. In this sense, it often operates as a force multiplier for wildlife conservation.
THE ENDANGERED SPECIES ACT
The Endangered Species Act employs a different conservation model. It establishes procedures for species listing, critical habitat designation, recovery planning, consultation, and incidental-take permitting.[xxxii] Unlike the MBTA, the ESA expressly addresses incidental take through statutory mechanisms. Activities affecting listed bird species may therefore trigger obligations under both statutes.
THREE DIFFERENT FEDERAL CONSERVATION MODELS
Taken together, the MBTA, Lacey Act, and ESA illustrate three different approaches to wildlife conservation: treaty-based protection, commerce-based enforcement, and recovery-oriented conservation. Understanding those distinctions helps explain why similar conduct may produce different legal consequences under different statutes.
COMPLIANCE CONSIDERATIONS
Organizations frequently employ biological assessments, avian risk evaluations, mitigation planning, monitoring programs, bird-safe design measures, and environmental training to reduce risk and improve decision-making. Early identification of wildlife issues can often reduce uncertainty and assist project planning.
CONCLUSION
For more than a century, the MBTA has reflected the principle that migratory birds are a shared resource, and their conservation transcends political boundaries. Whether future interpretations favor a narrow or expansive view of liability, the continuing debate over incidental take demonstrates that the statute remains a living law confronting modern environmental realities.
More than 100 years after its enactment, the MBTA continues to raise important questions regarding conservation, compliance, and the role of legal institutions in addressing changing conditions.
For attorneys, judges, and policymakers, the MBTA offers more than an exercise in statutory interpretation. It presents an opportunity to consider how legal institutions respond when longstanding laws encounter changing realities. As migratory birds continue their journeys across continents and jurisdictions, the questions raised by the MBTA remain remarkably relevant: What responsibilities accompany the use of shared natural resources? How to remain faithful to congressional intent in the application of long-standing statutes to modern economic development activities? And what role should legal institutions play in ensuring that future generations inherit the same seasonal migrations that have long defined the North American landscape?
The answers to those questions are still developing. The continuing evolution of the MBTA suggests that they are likely to remain the subject of legal and policy debate for years to come.
ABOUT THE AUTHOR
Charis L. Ward is an Oklahoma attorney focusing on animal and real property law. She is an adjunct professor at the OCU School of Law where she teaches intro to animal law. Mrs. Ward is the current chairman of the OBA Animal Law Section and a member of its Real Property Law Section and Environmental Law Section, as well as a member of the ABA Tort Trial and Insurance Practice Section’s Animal Law Committee and Companion Animals Subcommittee, and the Oklahoma City Real Property Lawyers Association.
ENDNOTES
[i] Migratory Bird Treaty Act, 16 U.S.C. §§703–712.
[ii] Id.
[iii]https://bit.ly/4bRfocP.
[iv] https://bit.ly/4xyTfse.
[v] https://bit.ly/4zk4mqC.
[vi] https://bit.ly/4ca6CHd.
[vii] The MBTS Selected Legal Issues – CRS-2025-8-12.
[viii] Id.
[ix] Id.
[x] State of Missouri v. Holland, 252 U.S. 416 (1920).
[xi]https://bit.ly/4xjLRBr.
[xii] Id.
[xiii] https://bit.ly/4zdPSbH; Migratory Bird Treaty Act, 16 U.S.C. §§703–712.
[xiv] https://bit.ly/4bRVzSK; https://bit.ly/4zigSHb.
[xv] State of Missouri v. Holland, 252 U.S. 416 (1920).
[xvi] U.S. v. FMC Corp., 572 F.2d 902 (2d Cir. 1978); U.S. v. Apollo Energies, Inc., 611 F.3d 679 (10th Cir. 2010).
[xvii] Migratory Bird Treaty Act, 16 U.S.C. §§703–712; https://bit.ly/4zgRxgC.
[xviii] Solicitor’s Opinion M-37085, (April 11, 2025).
[xix] Id.; Solicitor’s Opinion M-37065, (March 8, 2021).
[xx] Natural Resources Defense Council v. U.S. Dep’t of the Interior, 478 F. Supp. 3d 469 (S.D.N.Y.2020).
[xxi] Id.
[xxii] Id.
[xxiii] Solicitor’s Opinion M-37085, (April 11, 2025).
[xxiv]https://bit.ly/4qlNCLB.
[xxv] Id.
[xxvi]https://bit.ly/4ifdNkS.
[xxvii] https://bit.ly/4qiIGHm; https://bit.ly/3SdLoRH.
[xxviii] https://bit.ly/4g82yrR.
[xxix]https://bit.ly/4610BJ4.
[xxx] https://bit.ly/45tYflS.
[xxxi] Lacey Act, 16 U.S.C. §§3371-3378; https://bit.ly/4x1IqPm.
[xxxii] Endangered Species Act of 1973, 16 U.S.C. §§1531-1544.
Originally published in the Oklahoma Bar Journal – OBJ 97 No. 7 (September 2026)
Statements or opinions expressed in the Oklahoma Bar Journal are those of the authors and do not necessarily reflect those of the Oklahoma Bar Association, its officers, Board of Governors, Board of Editors or staff.