The Migratory Bird Treaty Act (MBTA): Selected Legal Issues

November 22, 2016 – January 25, 2022 R44694

The Migratory Bird Treaty Act (MBTA):
January 25, 2022
Selected Legal Issues
Linda Tsang
The Migratory Bird Treaty Act (MBTA) (16 U.S.C. §§ 703-712) was enacted in 1918 to
Legislative Attorney
implement a 1916 treaty signed by the United States and Great Britain (acting for Canada) aimed

at protecting birds that migrate between the two countries. Since 1918, the MBTA has been used
Erin H. Ward
as a vehicle to implement other bilateral migratory bird treaties. Under the MBTA, the
Legislative Attorney
Department of the Interior (DOI), through the U.S. Fish and Wildlife Service (FWS or Service),

administers a program that covers 1,093 species of migratory birds that are found in the United
States and covered by the treaties.

The application and enforcement of the MBTA have been the subject of significant legal debate.
The courts are divided on whether federal agencies are subject to the MBTA take prohibitions. In cases where federal
agencies have been considered subject to the MBTA take prohibitions, some courts have declined to apply the MBTA to
regulatory actions such as permit and project approvals, holding that agencies (1) have no affirmative duty to guarantee a
third-party permit holder’s future compliance with the MBTA and (2) are not subject to the MBTA when their regulatory
actions do not directly take migratory birds.
A wide range of federal district and appellate court cases have addressed the nature and scope of takings prohibited under the
MBTA. In general, the courts have looked at three different types of taking of migratory birds: (1) direct and intentional; (2)
direct and unintentional; and (3) indirect and unintentional (incidental). Courts generally agree that the MBTA prohibits
unpermitted direct and intentional actions that include hunting, shooting, wounding, killing, trapping, and capturing
migratory birds. Cases that involve direct actions that violate the MBTA prohibitions but lack intention or “guilty
knowledge” are generally viewed as strict liability crimes where proof of intent to take or knowledge of taking a migratory
bird is not needed to establish a misdemeanor violation of the MBTA.
However, jurisprudence on the applicability of the MBTA to incidental taking of migratory birds is less clear. Examples of
incidental takings include harm to migratory birds from the operation of facilities such as wastewater ponds or wind turbines.
Federal Courts of Appeals for the Second and Tenth Circuits have agreed with FWS that the MBTA is a strict liability statute
that applies to bird deaths that incidentally result from otherwise lawful activity. However, courts in the Fifth, Eighth, and
Ninth Circuits have held that the statute only applies to purposeful actions directed against migratory birds, such as hunting
and poaching. The legislative history of the MBTA supports differing interpretations of the nature and scope of the MBTA’s
taking prohibitions.
In the absence of direction or guidance from the Supreme Court or Congress on the scope of the MBTA’s take prohibitions,
DOI has issued several conflicting legal opinions over the course of several Administrations regarding whether the MBTA
prohibits the incidental taking or killing of migratory birds. During the Biden Administration, DOI has issued a legal opinion
that the MBTA prohibitions on taking and killing migratory birds by any means and in any manner include incidental taking
and killing. In 2021, FWS issued guidance implementing its position on incidental take, and clarifying its related enforcement
policies. The order announced plans to prioritize enforcement against incidental take from an otherwise illegal activity, or
foreseeable incidental take from legal activities that occur because “beneficial practices” to avoid or minimize incidental take
were not implemented. FWS has stated it plans to codify its interpretation of the MBTA as prohibiting incidental takings,
instead of relying on enforcement discretion. FWS is also considering authorizing certain types of incidental takings using a
combination of three regulatory tools: (1) exceptions to the MBTA’s prohibition on incidental takings; (2) general permits for
certain activity types; and (3) individual permits.
This report reviews the major provisions of the MBTA, examines the types of government action that are subject to the
MBTA, analyzes the conflicting judicial interpretations of the MBTA’s prohibition on taking or killing protected migratory
birds, and outlines DOI’s legal interpretation and enforcement of incidental taking under the MBTA.
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The Migratory Bird Treaty Act (MBTA): Selected Legal Issues

Background
The Migratory Bird Treaty Act (MBTA)1 was enacted in 1918 to implement a 1916 treaty signed
by the United States and Great Britain (acting for Canada) aimed at protecting birds that migrate
between the two countries.2 Since 1918, the MBTA has been amended to implement subsequent
bilateral migratory bird treaties between the United States and Mexico,3 Japan,4 and Russia.5
Under the MBTA, the Department of the Interior (DOI), through the U.S. Fish and Wildlife
Service (FWS or Service), administers a program that currently covers 1,093 species of migratory
birds that are found in the United States and covered by the treaties.6
This report discusses two legal issues regarding the MBTA and its prohibition on certain taking
and killing of migratory birds: the obligations of the federal government to comply with the
MBTA and the scope of its criminal penalties.
Major Provisions of the MBTA
The major provisions of the MBTA, summarized below, address taking of migratory birds,
permitted takings, enforcement, and penalties for violations. Other statutory provisions concern
unlawful transport or import of migratory birds;7 arrests and search warrants;8 state regulation;9
authorization of appropriations;10 breeding on farms and preserves;11 regulations implementing
the treaties and conventions;12 and seasonal takings for needs of indigenous Alaskans.13

1 16 U.S.C. §§ 703-712.
2 Convention between the United States and Great Britain for the Protection of Migratory Birds, U.S.-Gr. Brit., August
16, 1916, 39 Stat. 1702 [hereinafter U.S.-Canadian Treaty]. In 1995, the United States and Canada negotiated a
protocol that replaced the original treaty. Protocol Between the Government of the United States of America and the
Government of Canada Amending the 1916 Convention Between the United Kingdom and the United States of
America for the Protection of Migratory Birds in Canada and the United States, U.S.-Can., December 14, 1995, S.
Treaty Doc. No. 104–28, 2473 U.N.T.S. 329.
3 Convention between the United States of America and Mexico for the Protection of Migratory Birds and Game
Mammals, U.S.-Mex., February 7, 1936, 50 Stat. 1311. See also U.S. DEP’T OF STATE, TREATIES IN FORCE 296 (2020)
(listing subsequent amendments to the treaty). The MBTA was amended on June 20, 1936, to implement this treaty. 16
U.S.C. § 703.
4 Convention Between the Government of the United States of America and the Government of Japan for the Protection
of Migratory Birds and Birds in Danger of Extinction, and Their Environment, U.S.-Japan, March 4, 1972, 25 U.S.T.
3329. See also TREATIES IN FORCE at 238 (listing subsequent amendments to the treaty). The MBTA was amended on
June 1, 1975, to implement this treaty. 16 U.S.C. § 703.
5 Convention Between the United States of America and the Union of Soviet Socialist Republics [Russia] Concerning
the Conservation of Migratory Birds and Their Environment, U.S.-U.S.S.R., November 26, 1976, 29 U.S.T. 4674. The
MBTA was amended on November 8, 1978, to implement this treaty. 16 U.S.C. § 703.
6 See 50 C.F.R. § 10.13. The list of migratory birds protected under the MBTA also can be accessed at FISH &
WILDLIFE SERV., MIGRATORY BIRD TREATY ACT PROTECTED SPECIES (10.13 LIST) (2020), at https://www.fws.gov/birds/
management/managed-species/migratory-bird-treaty-act-protected-species.php (last visited Dec. 8, 2021).
7 16 U.S.C. § 705.
8 Id. § 706.
9 Id. § 708.
10 Id. § 709a.
11 Id. § 711.
12 Id. § 712(2).
13 Id. § 712(1).
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The Migratory Bird Treaty Act (MBTA): Selected Legal Issues

MBTA Section 2: The Prohibition on Taking and Killing of
Migratory Birds (16 U.S.C. § 703)
MBTA Section 2 prohibits several actions related to migratory birds, including taking and killing.
MBTA Section 2(a) states that:
Unless and except as permitted by regulations . . . , it shall be unlawful at any time, by any
means or in any manner, to pursue, hunt, take, capture, kill, attempt to take, capture, or
kill, possess, offer for sale, sell, offer to barter, barter, offer to purchase, purchase, deliver
for shipment, ship, export, import, cause to be shipped, exported, or imported, deliver for
transportation, transport or cause to be transported, carry or cause to be carried, or receive
for shipment, transportation, carriage, or export, any migratory bird, any part, nest, or egg
of any such bird, or any product . . . .14
The statute does not define the terms “hunt,” “take,” “capture,” or “kill,” and there is limited
guidance on the terms’ scope and limitations.15 The FWS regulations define the term “take” as “to
pursue, hunt, shoot, wound, kill, trap, capture, or collect” or to attempt to do so.16
MBTA Section 3: Permitted Take of Migratory Birds (16 U.S.C.
§ 704)
MBTA Section 3 allows the Secretary of the Interior to permit the taking of migratory birds under
certain circumstances.17 Under this authority, DOI has promulgated regulations for prescribed
migratory bird hunting and permits that allow taking of migratory birds for specific purposes.18
FWS regulations establish permitting requirements for various purposes, such as import, export,
banding or marking, scientific collecting, taxidermy, waterfowl sale and disposal, falconry,
propagation, rehabilitation, depredation, and population control.19 In addition, FWS has
authorized incidental take by the Armed Forces during military-readiness activities after a bill
was enacted in 2002 to permit this type of incidental taking of migratory birds.20
FWS may also issue special purpose permits for activities not covered by the other listed
categories.21 A special purpose permit is required before “any person” may lawfully take
migratory birds and may be obtained by sufficiently showing the “benefit to the migratory bird

14 16 U.S.C. § 703(a) (emphasis added).
15 The Secretary of the Interior may permit the take of migratory birds under certain circumstances. See 16 U.S.C.
§ 704(a) (authorizing DOI to “determine when, to what extent, if at all, and by what means, it is compatible with the
terms of the conventions to allow hunting, taking, capture, killing, possession, sale, purchase, shipment, transportation,
carriage, or export of any such bird, or any part, nest, or egg thereof, and to adopt suitable regulations permitting and
governing the same”).
16 50 C.F.R. § 10.12.
17 See 16 U.S.C. § 704(a) (authorizing DOI to “determine when, to what extent, if at all, and by what means, it is
compatible with the terms of the conventions to allow hunting, taking, capture, killing, possession, sale, purchase,
shipment, transportation, carriage, or export of any such bird, or any part, nest, or egg thereof, and to adopt suitable
regulations permitting and governing the same”).
18 50 C.F.R. pt. 20 (hunting regulations), id. pt. 21 (migratory bird permits).
19 50 C.F.R. pt. 21, subpt. C (import and export, banding or marking, scientific collecting, taxidermy, waterfowl sale
and disposal, special Canadian goose, falconry, raptor propagation, rehabilitation); subpt. D (depredation control);
subpt. E (population control).
20 50 C.F.R. § 21.25; Bob Stump National Defense Authorization Act for FY2003. P.L. 107-314, 116 Stat. 2458.
21 50 C.F.R. § 21.27.
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The Migratory Bird Treaty Act (MBTA): Selected Legal Issues

resource, important research reasons, reasons of human concern for individual birds, or other
compelling justification” of the activity.22
MBTA Section 5: Enforcement (16 U.S.C. § 706)
FWS has statutory authority and responsibility for enforcing the MBTA.23 Unlike the Endangered
Species Act, the MBTA does not include a citizen suit provision that allows “any person” to
enforce the MBTA provisions in court.24 However, citizen suits have been brought under the
Administrative Procedure Act’s (APA’s) prohibition against unlawful agency action.25 Section
702 of the APA “entitle[s]” a “person” who is “adversely affected or aggrieved by agency action”
to have a court review the challenged action.26 The U.S. Courts of Appeals for the District of
Columbia and Ninth Circuits have allowed civil suits seeking to enjoin government actions that
take or have the potential to take birds protected to proceed under the APA.27
MBTA Section 6: Penalty Provisions (16 U.S.C. § 707)
Failure to comply with the MBTA may result in either felony or misdemeanor penalties,
depending on the type of violation.28 Under MBTA Section 6(a), “any person, association,
partnership, or corporation” who violates the Act or its regulations is guilty of a misdemeanor and
can be fined no more than $15,000 and/or a maximum jail sentence of six months.29
The felony provision in MBTA Section 6(b) applies only to entities that knowingly take migratory
birds and sell or barter them, or have intent to do so.30 For felony violations, the punishment is a
fine of no more than $2,000 and/or a maximum jail sentence of two years.31
Government Actions Affecting Migratory Birds
Various government actions may affect birds that are protected under the MBTA. For example, a
federal agency could potentially implicate the MBTA by intentionally killing migratory birds in
an effort to control overpopulation or indirectly harm birds when their habitats are disturbed as

22 Id. § 21.27(a).
23 16 U.S.C. § 706.
24 Compare id. § 706 (authorizing DOI to enforce MBTA provisions), with 16 U.S.C. § 1540(g) (allowing “any person”
to file a lawsuit to enforce the ESA).
25 See 5 U.S.C. § 702 (“A person suffering legal wrong because of agency action, or adversely affected or aggrieved by
agency action within the meaning of a relevant statute, is entitled to judicial review thereof.”).
26 Id.
27 See, e.g., City of Sausalito v. O’Neill, 386 F.3d 1186, 1203, 1204 (9th Cir. 2004) (holding that “anyone who is
‘adversely affected or aggrieved’ by an agency action alleged to have violated the MBTA has standing to seek judicial
review of that action”); Humane Soc’y of the U.S. v. Glickman, 217 F.3d 882, 886 (D.C. Cir. 2000) (citing 5 U.S.C.
§ 702 of the APA, Am. School of Magnetic Healing v. McAnnulty, 187 U.S. 94 (1902), and Noble v. Union River
Logging Co., 147 U.S. 165 (1893), as authority allowing for judicial review of government actions regarding
compliance with the MBTA).
28 16 U.S.C. § 707(a)–(b).
29 Id. § 707(a).
30 Id. § 707(b).
31 Id. § 707(b).
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part of managing federal lands and property.32 Whether these actions violate the MBTA take
prohibitions depends on whether federal agencies are subject to the MBTA.
The courts have differing opinions on the applicability of the MBTA to federal agencies. U.S.
Courts of Appeals for the Eighth and Eleventh Circuits33 have held that the MBTA can be
enforced only through its MBTA Section 6 penalty provisions, which courts have agreed do not
apply to federal agencies. However, where there is a separate enforcement authority such as the
APA that provides a civil remedy, courts following the D.C. Circuit’s precedent would require the
federal government to comply with the MBTA take prohibitions.
Cases Holding That Federal Agency Actions Are Not Subject to MBTA Take
Prohibitions
Several courts have concluded that the MBTA take provisions do not apply to federal agencies. In
Sierra Club v. Martin, Sierra Club challenged the U.S. Forest Service’s (USFS’s) timber-cutting
and road-building activities as violating the MBTA by relying on Section 706 of the APA, a
provision that requires reviewing courts to “hold unlawful and set aside agency action, findings,
and conclusions found to be . . . arbitrary, capricious, an abuse of discretion, or otherwise not in
accordance with law.”34 Specifically, in Martin, Sierra Club claimed that the USFS activities
would disturb the nesting season of certain migratory birds and result in the illegal taking of
between 2,000 and 9,000 migratory birds.35
The Eleventh Circuit denied review under the APA, explaining that, under the APA, an “agency’s
actions could only fail to be ‘in accordance with law’ when that agency’s actions are subject to
that law.”36 The Eleventh Circuit reversed an injunction issued by the district court, holding that
the federal government and its officials were not subject to the MBTA according to the plain
meaning of the statute and the legislative intent.37 The court concluded that, in reading the statute
as a whole, the MBTA is a “criminal statute making it unlawful only for persons, associations,
partnerships, and corporations to ‘take’ or ‘kill’ migratory birds,” and the MBTA “does not
subject the federal government to its prohibitions.”38
To support its conclusion, the court determined that there was “no congressional intent” that
“person,” as used in Section 6(a) regarding misdemeanor penalties, includes the “federal
government[,] . . . federal agency, or a federal official acting in his official capacity.”39 The court
emphasized the MBTA’s historical context, explaining that the application of the MBTA to the

32 See, e.g., Humane Soc’y of the U.S. v. Glickman, 217 F.3d 882, 883-84 (D.C. Cir. 2000) (addressing whether the
MBTA prohibits federal agencies from killing or taking migratory birds without a permit to address geese
overpopulation in Virginia); City of Sausalito v. O’Neill, 386 F.3d 1186, 1203-04 (9th Cir. 2004) (addressing whether
rehabilitation of a former military base that may result in the “foreseeable deaths” of migratory birds because of
disturbance to migratory birds and their nests violated the MBTA).
33 This report references a significant number of decisions by federal appellate courts of various regional circuits. For
purposes of brevity, references to a particular circuit in the body of this report (e.g., the Fifth Circuit) refer to the U.S.
Court of Appeals for that particular circuit.
34 Sierra Club v. Martin, 110 F.3d 1551 (11th Cir. 1997); 16 U.S.C. § 706(2)(A).
35 Martin, 110 F.3d at 1553.
36 Id. at 1555.
37 Id. at 1554-55. The U.S. District Court for the Northern District of Georgia issued the preliminary injunction. 933 F.
Supp. 1559 (N.D. Ga. 1996).
38 Id.
39 Id.
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federal government would “severely impair” the USFS’s obligation “to furnish a continuous
supply of timber” for the country, a duty that would “inevitably” result in deaths of birds and
destruction of nests.40 The court explained that Congress intended that regulatory programs
developed under the National Forest Management Act (NFMA) and the National Environmental
Policy Act (NEPA)—both enacted after the MBTA—would ensure that the USFS considers the
impact of federal land management on migratory birds.41
Soon after the Eleventh Circuit’s decision in Sierra Club v. Martin, the Eighth Circuit addressed
similar issues in Newton County Wildlife Association v. U.S. Forest Service.42 In this case,
nongovernmental organizations (NGOs) alleged that the USFS violated the MBTA by failing to
obtain “special permits” from the FWS for timber sales that would disrupt nesting of migratory
birds and result in the death of some birds.43 After concluding that jurisdiction to review the
timber sales fell under the NFMA, and not the APA, the court narrowed the issue to whether the
USFS’s actions under the NFMA were arbitrary and capricious because the agency “ignored or
violated” its obligations under the MBTA.44 Similar to the Eleventh Circuit’s reasoning in Sierra
Club v. Martin, the court determined that the term “person” under Section 6 penalty provisions
did not apply to sovereign governments based on common usage.45 The court rejected the NGOs’
arguments that the MBTA must cover federal agencies if the U.S. government were to maintain
its 1916 treaty obligations, concluding that the government’s obligation to comply with the treaty
came from the treaty itself.46 The parties’ obligations under the treaty, the court explained, are to
execute the treaty, which the United States did by enacting a statute that applies to private
parties.47 The Eighth and Eleventh Circuits did not address whether the MBTA Section 2 take
prohibitions apply to federal agencies independent from the Section 6 penalty provisions.
Cases Holding That Federal Agency Actions Are Subject to MBTA Take
Prohibitions
Other courts have held that the MBTA does apply to the federal government by focusing on who
is subject to the MBTA Section 2 prohibitions as opposed to who is subject to the Section 6
penalties. For example, in Humane Society of the United States v. Glickman, the D.C. Circuit
addressed whether the MBTA prohibits federal agencies from killing or taking migratory birds
without a permit from DOI.48 In this case, the Department of Agriculture planned to capture and
kill Canadian geese without a FWS depredation permit to address the negative impacts to crops
and water quality from geese overpopulation in Virginia.49

40 Id. at 1556.
41 Id. The National Forest Management Act was enacted in 1960. P.L. 86-517, 74 Stat. 215 (1960) (codified at 16
U.S.C. §§ 1600-1614). The National Environmental Policy Act was enacted in 1970. P.L. 90-190, 83 Stat. 852
(codified at 42 U.S.C. §§ 4321-4355).
42 113 F.3d 110 (8th Cir. 1997). The Martin decision, supra note 34, was published on April 29, 1997, and the Newton
County decision was published on May 6, 1997.
43 Id. at 115.
44 Id. at 114.
45 See id. (concluding that “the sovereign” is necessarily excluded from the definition of “person”). The court did not
address whether the “sovereign” included federal officers acting in their official capacity. Id.
46 Id. at 115.
47 Id.
48 217 F.3d 882 (D.C. Cir. 2000).
49 Id. at 883-84.
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Although the court agreed with the agency that the misdemeanor penalty provisions in MBTA
Section 6(a) do not apply to federal agencies,50 the court turned to Section 2 to determine if the
agency was separately subject to its prohibition on killings and takings of migratory birds without
a permit.51 The court held that the MBTA Section 2 prohibitions do apply to federal agencies
based primarily on the plain meaning of the statute.52 The court explained that Section 2 does not
restrict its prohibition to private parties and provides no exemption for federal agencies.53 In
addition, the court rejected the agency’s argument that Congress did not intend for Section 2 to
apply to federal agencies because there is no means to enforce the restrictions if the Section 6(a)
misdemeanor penalties do not apply, and there is no provision for injunctive relief in the statute.54
In disagreeing with the Sierra Club v. Martin decision from the Eleventh Circuit and the Newton
County Wildlife Association decision from the Eighth Circuit discussed above, the court
concluded that both decisions rest on the “mistaken idea that in 1918, [Section 2] could be
enforced only through the criminal penalty provision in [Section 6](a).”55 The court cited the APA
and other Supreme Court cases that allow equitable or injunctive relief for suits against federal
officers for failing to comply with a specific statute.56 Ultimately, the court held that the agency
did violate the MBTA by failing obtain a permit to take the geese.57
The Humane Society court, in disagreement with the Eleventh Circuit decision in Sierra Club v.
Martin, concluded that it would be “odd” if federal agencies were exempt from the Section 2
prohibitions because the U.S.-Canadian treaty underlying the MBTA “binds the contracting
parties” to its terms.58 Article II of the treaty prohibits hunting of specific types of migratory birds
during certain seasons, and Article V prohibits takings of nest or eggs of migratory birds at all
times.59 The court stated that “the fact that the [MBTA] enforced a treaty between our country and
Canada reinforces our conclusion that the broad language of §703 [MBTA Section 2] applies to
actions of the federal government.”60
Scope of Federal Actions Subject to the MBTA
Among the courts that have applied the MBTA to federal agency actions, some courts have
distinguished between (1) government actions that are directed at migratory birds, and

50 The agency argued, and the court agreed, that “person” as identified in the MBTA Section 2 prohibition on take does
not ordinarily include the sovereign. See id. at 886 (citing Vt. Agency of Nat. Res. v. United States, 529 U.S. 765, 780
(2000)). The court pointed out that the agency did not discuss whether federal officers carrying out the take of
migratory birds would be considered “persons” under MBTA Section 6, and the court did not address it. Id. However,
as discussed above, the court determined that even if the sovereign was not subject to the Section 6 penalties, federal
agencies are still subject to the Section 2 take prohibitions and civil suits. Id.
51 Id. at 883-84.
52 Id. at 883.
53 Id. at 885.
54 Id. at 886.
55 Id. at 888 (emphasis added).
56 See id. at 886 (citing 5 U.S.C. § 702 of the APA and Am. School of Magnetic Healing v. McAnnulty, 187 U.S. 94
(1902)).
57 Id. at 888.
58 Id. at 887. See U.S.-Canadian Treaty, supra note 2 (citing the closing proclamation in the treaty where President
Woodrow Wilson states that “the same and every article and clause thereof may be observed and fulfilled with good
faith by the United States and the citizens thereof”).
59 See U.S.-Canadian Treaty, supra note 2 (explaining that exceptions for take are allowed for “scientific or
propagating purposes”).
60 Id. at 887.
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(2) regulatory actions (e.g., approving projects or granting permits) relating to third-party projects
that take or could take migratory birds. In cases where the government intentionally kills
migratory birds, courts require federal agencies to comply with the MBTA and obtain the
necessary permits under Section 3.61 However, courts have declined to apply the MBTA to
regulatory actions related to third-party projects based on two main principles: (1) agencies are
not subject to the MBTA when their regulatory actions do not directly take migratory birds; and
(2) agencies have no affirmative duty to guarantee a third-party’s future compliance with the
MBTA.
These principles are best illustrated in Protect Our Communities Foundation v. Jewell, a Ninth
Circuit case decided in June 2016.62 Environmental groups claimed, among other things, that the
U.S. Bureau of Land Management (BLM) (1) violated the MBTA by granting a right-of-way on
public lands to a private company to develop and operate a wind energy facility that would
incidentally take migratory birds; or (2) in the alternative, violated the APA because the BLM
failed to require the facility to secure an MBTA take permit prior to granting the right-of-way.63 In
affirming summary judgment for BLM, the Ninth Circuit rejected both claims, holding that the
MBTA does not contemplate “secondary” liability of agencies that act in a purely regulatory
capacity where those regulatory actions do not “directly or proximately cause the ‘take’ of
migratory birds.”64 The court concluded that the APA and MBTA place no “affirmative duty” on
BLM to guarantee a grantee’s future compliance with the MBTA or prevent future unlawful
action by a grantee.65
Similarly, the U.S. District Court for the District of Maine rejected a challenge of U.S. Army
Corps of Engineers’ (Corps’) issuance of a Clean Water Act Section 404 permit as a violation of
the MBTA.66 In granting summary judgment for the Corps, the court held the “relationship
between the Corps’ regulatory permitting activity and any potential harm to migratory birds
appears to be too attenuated to support a direct action against the Corps to enforce the MBTA’s
prohibition on ‘takes.’”67
The issue of whether a federal agency is subject to the MBTA when approving permits under
separate regulatory programs arises often in litigation over energy infrastructure projects. For
example, in Public Employees for Environmental Responsibility v. Beaudreau, the U.S. District
Court for the District of Columbia rejected the plaintiffs’ claim that the Bureau of Ocean Energy
Management (BOEM) violated the MBTA by approving the Cape Wind energy project without
first obtaining a permit from FWS for the taking of migratory birds.68 In granting summary
judgment to the agency, the court held that BOEM did not violate the MBTA by merely approving
a project that, if ultimately constructed, might result in the taking of migratory birds by the wind

61 See, e.g., Pub. Emps. for Env’t Responsibility v. FWS, No. 14-1807, 2016 U.S. Dist. LEXIS 40935, at *2-3 (D.D.C.
March 29, 2016) (requiring the FWS to issue a depredation permit to kill double-crested cormorants when they threaten
to eat commercially raised fish stock); Glickman, 217 F.3d at 888 (holding that the proposed federal actions that
included intentional and direct take of migratory geese to control overpopulation were subject to the MBTA).
62 825 F.3d 571 (9th Cir. 2016).
63 Id. at 585-86.
64 Id. at 585.
65 Id. at 586-88.
66 Friends of the Boundary Mountains v. U.S. Army Corps of Eng’rs, 24 F. Supp. 3d 105, 113-15 (D. Me. 2014).
67 Id. at 114.
68 Pub. Emps. for Env’t Responsibility v. Beaudreau, 25 F. Supp. 3d 67, 117-18 (D.D.C. 2014), rev’d on other grounds,
827 F.3d 1077 (D.C. Cir. 2016).
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turbines.69 The court concluded that even if BOEM is required to obtain a permit, it is unclear
whether it is required to do so prior to when the project is operational or at least after construction
has commenced when a potential take is “more imminent.”70 On appeal, the D.C. Circuit did not
address the MBTA issue because BOEM conceded that an MBTA take permit was required and
that Cape Wind intended to apply for one.71
Similarly, in Protect Our Communities Foundation v. Chu, the U.S. District Court for the
Southern District of California dismissed a claim that the Department of Energy was required to
obtain a permit under the MBTA prior to issuing a permit approving the construction of a cross-
border electric transmission line that would connect a wind power project to the electricity
grid.72 The court determined that the agency is not required to obtain an MBTA permit “for an
unintentional, third party killing of migratory birds incident to construction of a project.”73
Accordingly, the courts appear reluctant to place responsibility on federal agencies for the actions
of third parties that will likely take migratory birds as a result of federal approval of the
underlying action. In 2015, FWS appeared to agree with the courts by stating that “the agencies
themselves are not subject to the prohibitions of the MBTA when acting in their regulatory
capacities.”74 Nonetheless, even if a federal agency is not required to obtain an MBTA permit, the
third party may need to obtain a permit for incidental take related to the project.75
Scope of Takings Prohibited Under the MBTA
As discussed above, MBTA Section 2(a) makes it unlawful to, among other things, “kill” or
“take” a migratory bird (or its nest or eggs), acts that are punishable under Section 6(a) as
misdemeanor crimes.76 Courts have been faced with defining what constitutes a “taking” of
migratory birds under the MBTA. As described above, although the statute itself does not define
the term “take,” the MBTA regulations define the term “take” as “to pursue, hunt, shoot, wound,
kill, trap, capture, or collect.”77
In general, the courts have looked at three different types of actions or omissions that result in the
taking of migratory birds:
1. direct and intentional acts or omissions;
2. direct and unintentional acts or omissions; and

69 Id. at 117-18, 130.
70 Id. at 118.
71 Pub. Emps. for Env’t Responsibility v. Hopper, 827 F.3d 1077, 1088 n.11 (D.C. Cir. 2016).
72 Protect Our Cmtys. Found. v. Chu, No. 12 Civ. 3062, 2014 U.S. Dist. LEXIS 42410, at *25-26 (S.D. Cal. March 27,
2014).
73 Id. at 26. See also Protect Our Cmtys. Found. v. Salazar, No. 12 civ. 2211, 2013 U.S. Dist. LEXIS 159281, at *51-55
(S.D. Cal. 2013) (holding that project opponents failed to demonstrate that a permit was required under the MBTA
when the BLM approved a wind power project in Southern California).
74 Migratory Bird Permits; Programmatic Environmental Impact Statement; Notice of Intent, 80 Fed. Reg. 30,032,
30,034 (May 26, 2015).
75 See, e.g., Hopper, 827 F.3d at 1089 n.11 (noting that the agency conceded that the wind energy developer was
required to obtain a permit for incidental take of migratory birds from wind turbines).
76 16 U.S.C. §§ 703(a), 707(a). Knowingly taking a migratory bird to sell or with the intention of selling it is a felony
crime under § 707(b).
77 50 C.F.R. § 10.12.
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3. indirect and unintentional acts or omissions (incidental take).
In examining these different types of takings of migratory birds, courts have reviewed the plain
meaning, statutory construction, legislative history, and the constitutionality of the MBTA to
determine whether the actions or omissions violate the statute. There is a wide range of federal
district and appellate court cases that have addressed this issue. Below is a review of selected
cases that provide examples of the major issues that courts have faced when determining the
reach of the MBTA.
Direct and Intentional Take
Courts generally agree that FWS’s regulatory definition of “take” prohibits unpermitted direct
and intentional actions that include hunting, shooting, wounding, killing, trapping, and capturing
migratory birds.78 Direct actions refer to actions that kill a migratory bird, whereas intentional
acts are those actions that intend to kill a bird for a specific purpose. For example, in the D.C.
Circuit decision, United States v. Glickman, discussed above, the Department of Agriculture’s
planned actions to capture and kill Canadian geese to prevent overpopulation was viewed as
being intentional and directed at protected migratory birds.79 The D.C. Circuit held that the
agency violated the MBTA by failing to obtain a depredation permit prior to taking the geese.80
Direct and Unintentional Take
Several cases involve direct actions that violate the MBTA prohibitions but lacked intention or
“guilty knowledge.” Generally, a criminal offense consists of both a prohibited act (the actus
reus) and a guilty mind (the mens rea, also known as the “scienter” requirement).81 A criminal
offense that does not require the mens rea element is viewed as a strict liability crime.82 In the
context of the MBTA, the prohibitions under Section 2(a) are generally viewed as strict liability
crimes, and proof of intent to take or knowledge of taking a migratory bird is not needed to
establish a misdemeanor violation of the Act.
For example, in 1997, the Tenth Circuit decision in United States v. Corrow affirmed a criminal
conviction for possession of eagle feathers in violation of Section 2’s prohibition against
possessing any part of a migratory bird.83 For the court, no mens rea was needed for a conviction:
“Simply stated, . . . ‘it is not necessary to prove that a defendant violated the Migratory Bird
Treaty Act with specific intent or guilty knowledge.’”84 The court concluded that the “plain
language of §703 [MBTA Section 2] renders simple possession of protected feathers unlawful.”85

78 See 50 C.F.R. § 10.12 (defining “take” as to pursue, hunt, shoot, wound, kill, trap, capture, or collect, or attempt to
pursue, hunt, shoot, wound, kill, trap, capture, or collect” migratory birds).
79 Humane Soc’y of the U.S. v. Glickman, 217 F.3d 882, 883 (D.C. Cir. 2000). See “Cases Holding That Federal
Agency Actions Are Subject to MBTA Take Prohibitions” section, supra, for discussion of this case.
80 Id. at 888.
81 For background on the mens rea requirement in criminal law, see CRS Report R46836, Mens Rea: An Overview of
State-of-Mind Requirements for Federal Criminal Offenses, by Michael A. Foster.
82 Id. at 8.
83 United States v. Corrow, 119 F.3d 796, 798 (10th Cir. 1997).
84 See id. at 805 (quoting United States v. Manning, 787 F.2d 431, 435 n.4 (8th Cir. 1986)).
85 Id.
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Other situations that involve direct but unintentional deaths of migratory birds generally involve
MBTA Section 3(b)’s prohibition on taking birds by baiting.86 Prior to the MBTA amendments in
1998, courts held that there was no need to prove that the defendant intentionally baited a field to
attract migratory birds or had knowledge that the field was baited to violate Section 704(b)’s
prohibition because it was a strict liability crime.87 Congress amended the MBTA in 1998 to
remove the strict liability standard making it unlawful to take migratory birds by aid of baiting if
the person “knows or reasonably should know” that an area is baited.88
Indirect and Unintentional (Incidental) Take
Various DOI legal opinions define “incidental take” as “take that results from an activity, but is
not the purpose of that activity.”89 Courts have addressed what types of incidental take trigger the
MBTA’s strict liability for misdemeanor offences, resulting in conflicting interpretations. Courts
are split on whether the MBTA’s prohibition on taking of migratory birds includes incidental bird
deaths that result from, but are not the purpose of, another lawful activity (e.g., industrial
operations that inadvertently cause a migratory bird death, or destruction or modification of a bird
habitat that will likely result in migratory bird deaths).
Broad Application of the Take Prohibitions in the Second and Tenth Circuits
Courts in the Second and Tenth Circuits view the taking of birds protected under the MBTA as
strict liability crimes with varying limitations. For example, in a 1978 case involving preventable
incidental deaths of migratory birds, the Second Circuit focused on the hazardous nature of
pesticide manufacturing in evaluating the scope of the MBTA. In United States v. FMC Corp., the
Second Circuit affirmed the conviction of a manufacturer of pesticides for killing migratory birds
as a result of storing wastewater in a retaining pond frequented by migratory birds.90 The court
analogized the migratory bird injuries resulting from FMC’s “affirmative act” of manufacturing
“highly toxic” pesticides manufacturing to claims based on strict liability torts.91 The court
concluded that lack of a statutory requirement of intention as an element of the MBTA Section 2
takings prohibition, the relatively minor fines imposed, congressional recognition of the public
policy to protect migratory birds, and FMC’s failure to prevent lethal amounts of the chemicals in
the wastewater from the pond were sufficient reasons to impose strict liability.92

86 MBTA regulations define “baiting” as “direct or indirect placing, exposing, depositing, distributing, or scattering of
salt, grain, or other feed that could serve as a lure or attraction for migratory game birds to, on, or over any areas where
hunters are attempting to take them.” 50 C.F.R. § 20.11(g).
87 See United States v. Catlett, 747 F.2d 1102, 1104 (6th Cir. 1984) (affirming conviction for a dove hunt in a field nine
days after authorities had discovered that the field had been baited). See also United States v. Hogan, 89 F.3d 403, 404
(7th Cir. 1996) (“The offense is a strict liability crime; a defendant is responsible whether or not he knew the area was
baited.”).
88 Migratory Bird Treaty Reform Act of 1998, P.L. 105-312, 112 Stat. 2956 (codified as amended at 16 U.S.C. §
704(b)).
89 Memorandum M–37041 from Solicitor at 1, DOI, to Dir., FWS (Jan. 10, 2017), withdrawn and replaced by
Memorandum M–37050 from Principal Deputy Solicitor, DOI, to Sec’y. DOI (Dec. 22, 2017) [hereinafter Opinion M-
37041]; Memorandum M–37050 from Principal Deputy Solicitor, DOI, to Sec’y DOI (Dec. 22, 2017), vacated Nat.
Res. Def. Council, Inc. v. U.S. Dep’t of the Interior, 478 F. Supp. 3d 469 (S.D.N.Y. 2020) [hereinafter Opinion M-
37050].
90 United States v. FMC Corp., 572 F.2d 902 (2d Cir. 1978).
91 Id. at 908.
92 Id.
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Since FMC Corp., several federal courts have limited the application of strict liability in the
context of the MBTA by requiring that the acts or omissions must be the proximate cause of the
incidental migratory bird taking (i.e., the injury caused must have been reasonably anticipated or
foreseen as a natural consequence of the activity).93 Similar to FMC Corp., some courts view the
failure to take preventive or corrective measures in hazardous activities that result in foreseeable
incidental takings of migratory birds as a strict liability offense. For instance, in United States v.
Corbin Farm Service, a federal district court in California held that the MBTA applied to
defendants that accidentally poisoned migratory ducks by applying pesticide to an alfalfa field,
noting that Section 2 made it illegal to kill migratory birds “by any means or in any manner.”94 In
imposing strict liability for the accidental poisoning, the court concluded that the “guilty act alone
is sufficient to make out the crime.”95 The court also noted that a person applying pesticides
might be able to foresee the danger to migratory birds and prevent it, unlike a car driver who is
not in a reasonable position to prevent the bird’s death.96
Similarly, in 1999, in United States v. Moon Lake Electric Association, the U.S. District Court for
the District of Colorado held that Moon Lake Inc., a rural electrical distribution cooperative,
violated the MBTA by failing to take protective measures to prevent migratory birds from being
electrocuted by its power lines.97 The court rejected the plaintiff’s arguments that it did not violate
the MBTA because the electrocutions were unintentional and that Congress intended to target
only intentional harmful acts such as hunting and poaching.98 The court recognized that the plain
text of Section 2 made it illegal to kill migratory birds “at any time, by any means or in any
manner.”99 In addition, the court concluded that “[by] prohibiting the act of ‘killing’ in addition to
the acts of hunting, capturing, shooting, and trapping, the MBTA’s language and regulations
suggest that Congress intended to prohibit conduct beyond that normally exhibited by hunters and
poachers. Indeed, the MBTA does not seem overly concerned with how captivity, injury, or death
occurs.”100 However, the court did acknowledge that “[a]lthough section 707(a) of the MBTA
imposes strict liability, . . . the government must prove that Moon Lake’s power lines constitute
the cause in fact, as well as the proximate cause, of death” of the birds, meaning that there are
limits on the scope of criminal liability under the MBTA for incidental takings.101
Another Tenth Circuit case recognizing but restricting the scope of strict liability offenses under
the MBTA was United States v. Apollo Energies, Inc.102 In 2010, 13 years after its decision in
United States v. Corrow that held that violating Section 2’s prohibition against possessing any
part of a migratory bird was a strict liability offense, the Tenth Circuit emphasized that
constitutional constraints require that application of strict liability to incidental takings of

93 See United States v. Apollo Energies, Inc., 611 F.3d 679, 690 (10th Cir. 2010) (citing BLACK’S LAW DICTIONARY
(6th ed. 1990)).
94 United States v. Corbin Farm Serv., 444 F. Supp. 510, 532 (E.D. Cal. 1978), aff’d on other grounds, 578 F.2d 259
(9th Cir. 1978).
95 Id. at 536.
96 Id.
97 United States v. Moon Lake Elec. Ass’n, Inc., 45 F. Supp. 2d 1070, 1074 (D. Colo. 1999).
98 Id. at 1072.
99 Id.
100 Id. at 1074.
101 Id. at 1077. “Cause in fact” is generally defined as the “cause without which the event could not have occurred.”
BLACK’S LAW DICTIONARY (10th ed. 2014)
102 611 F.3d 679 (10th Cir. 2010).
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migratory birds be limited to actions or omissions that proximately caused the bird deaths.103 In
United States v. Apollo Energies, Inc., the Tenth Circuit affirmed the conviction of oil drilling
operators as violating the MBTA when dead migratory birds were discovered lodged in pieces of
their oil drilling equipment.104 First, the court held that “[a]s a matter of statutory construction,
the ‘take’ provision of the Act does not contain a scienter requirement,” acknowledging that it
was bound by its holding in Corrow that addressed this issue.105
Second, the court rejected the operators’ argument that application of the MBTA would be
unconstitutional because the statute fails to provide adequate notice of what conduct constitutes a
crime, requiring the statute to require prosecutors to prove proximate causation.106 The court
explained that the MBTA is not unconstitutionally vague because it “criminalizes a range of
conduct that will lead to the death or captivity of protected migratory birds. . . . The actions
criminalized by the MBTA may be legion, but they are not vague.”107 The court further concluded
that because due process requires that criminal defendants have adequate notice that their conduct
is a violation of the law, “a strict liability interpretation of the MBTA for the conduct charged here
satisfies due process only if defendants proximately caused the harm to protected birds.”108 The
court explained the following:
Questions abound regarding what types of predicate acts—acts which lead to the MBTA’s
specifically prohibited acts—can constitute a crime. Conceptually, the constitutional
challenge to the criminalization of these predicate acts can be placed under the rubric of
notice or causation. The inquiries regarding whether a defendant was on notice that an
innocuous predicate act would lead to a crime, and whether a defendant caused a crime in
a legally meaningful sense, are analytically indistinct, and go to the heart of due process
constraints on criminal statutes. . . . When the MBTA is stretched to criminalize predicate
acts that could not have been reasonably foreseen to result in a proscribed effect on birds,
the statute reaches its constitutional breaking point.109
The court agreed with the lower court’s assessment of proximate cause in concluding that
“proximate cause is an ‘important and inherent limiting feature’ to the MBTA, and that liability
would attach where the injury ‘might be reasonably anticipated or foreseen as a natural
consequence of the wrongful act.’”110 In affirming the convictions, the court held that the record
showed that it was reasonably foreseeable that protected birds could be trapped in the operators’

103 United States v. Corrow, 119 F.3d 796, 798 (10th Cir. 1997). See “Direct and Unintentional Take” section, supra,
for discussion of this case.
104 United States v. Apollo Energies, Inc., 611 F.3d 679, 682 (10th Cir. 2010). In this case, migratory birds were
attempting to nest in the oil drilling operator’s cylindrical heaters and then died when they could not escape. Id. In
2005, FWS initiated an educational campaign to alert oil producers and suggest protective measures to prevent
migratory bird deaths. Id. at 682-83. During the campaign, FWS also chose not to recommend prosecution for MBTA
violations related to heaters through the end of 2006. Id. at 683. After the grace period ended, FWS agents searched a
heater belonging to Apollo Energies Inc. and Dale Walker. Id. Defendant Apollo was later convicted after dead
migratory birds were found in 2007, and Defendant Walker was convicted after dead birds were found during
inspections in April 2007 and April 2008. Id.
105 Id. at 686.
106 Id. at 689-690.
107 Id. at 689.
108 Id. at 682.
109 Id. at 689-90.
110 Id. at 690 (citing United States v. Moon Lake Elec. Ass’n, Inc., 45 F. Supp. 2d 1070 (D. Colo. 1999)).
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equipment because the operators had knowledge and notice from FWS that its equipment had the
potential to trap and kill protected birds for nearly a year and a half before the bird deaths.111
Narrow Application of the Take Prohibitions in the Eighth and Ninth Circuits
Courts in the Eighth and Ninth Circuits have taken a more narrow view by limiting the MBTA’s
take prohibitions to deliberate and intentional conduct directed at birds, such as hunting and
poaching, and not acts or omissions having merely the incidental or unintended effect of causing
bird deaths, such as federal activities that modify or disturb bird habitats or accidental deaths
from commercial activity.112 In so holding, these courts have focused on the common law
meaning of the term “take” as used and defined in the MBTA and other statutes to conclude that
the MBTA prohibition is limited to intentional and direct action.113 In addition, these courts have
compared the MBTA to the Endangered Species Act (ESA) that specifically addresses incidental
take of endangered species.114 The ESA’s definition of a “take” includes activities that “harm” or
“harass” threatened or endangered wildlife.115 For the ESA, FWS defined “harm” to include
wildlife deaths that are proximately caused by “habitat modification.”116 In 1982, Congress
amended the ESA, authorizing FWS to issue incidental take permits under certain
circumstances.117 “Incidental take” is defined in the ESA as a wildlife take that is “incidental to,
and not the purpose of, the carrying out of an otherwise lawful activity.”118
The Ninth Circuit relied on the different definitions of “take” adopted in the ESA and the MBTA
in Seattle Audubon Society v. Evans to limit the scope of the MBTA taking prohibition to direct
and intentional action.119 In that case, the court held that the MBTA does not prohibit the USFS
and the BLM from selling and logging timber from lands within areas that may provide suitable
habitat for the northern spotted owl.120 The court stated the MBTA’s use of “take” refers to
“physical conduct engaged in by hunters and poachers, conduct which was undoubtedly a concern
at the time of the statute’s enactment in 1918. The statute and regulations promulgated under it
make no mention of habitat modification or destruction.”121 The court noted that unlike the
MBTA regulatory definition of “take,” the ESA’s definition of “take” includes the term “harm,”
which encompasses habit modification or degradation.122 In relying on this distinction, the court
concluded that the agencies’ logging and sale of timber, which was viewed as being likely to

111 See id. at 691 (affirming two of the convictions where the operators received notice of the equipment’s potential to
trap and kill migratory birds prior to the birds’ deaths and vacating one conviction because there was no evidence that
the operator was aware of problems with heater-treaters in the oil industry or in his specific operations prior to the FWS
educational campaign).
112 See, e.g., United States v. Brigham Oil & Gas, L.P., 840 F. Supp. 2d 1202 (D.N.D. 2012); Newton Cty. Wildlife
Ass’n v. U.S. Forest Ser. 113 F.3d 110 (8th Cir. 1997), Seattle Audubon Soc’y v. Evans, 952 F.2d 297 (9th Cir. 1991).
113 See id.
114 16 U.S.C. § 1539(a). See, e.g., Seattle Audubon Soc’y v. Evans, 952 F.2d 297 (9th Cir. 1991).
115 16 U.S.C. § 1532(19).
116 50 C.F.R. § 17.3.
117 Endangered Species Act Amendments of 1982, P.L. 97-304, 96 Stat. 1411 (codified as amended at 16 U.S.C. §
1539(a)).
118 16 U.S.C. § 1539(a).
119 Seattle Audubon Soc’y, 952 F.2d at 302.
120 Id.
121 Id.
122 Id. at 303.
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destroy migratory birds’ habitat, did not violate the MBTA.123 In distinguishing the United States
v. FMC Corp. and United States v. Corbin Farm Service decisions discussed above, the court
explained that those cases (which addressed unintentional deaths of migratory birds through
pesticide manufacturing and use) “do not suggest that habitat destruction, leading indirectly to
bird deaths, amounts to the ‘taking’ of migratory birds within the meaning of the MBTA.”124 The
court concluded that “[h]abitat destruction causes ‘harm’ to the owls under the ESA but does not
‘take’ them within the meaning of the MBTA.”125
In Newton County Wildlife Association v. U.S. Forest Service, the Eighth Circuit joined the Ninth
Circuit, holding that the USFS did not violate the MBTA by failing to obtain “special permits”
from the FWS for timber sales that would disrupt nesting of migratory birds and result in the
death of some birds.126 As noted above, the court determined that the MBTA did not apply to the
government.127 The court further concluded that the death of birds as a result of timber harvesting
did not constitute a take under MBTA Section 2, explaining that “[s]trict liability may be
appropriate when dealing with hunters and poachers. But it would stretch this 1918 statute far
beyond the bounds of reason to construe it as an absolute criminal prohibition on conduct, such as
timber harvesting, that indirectly results in the death of migratory birds.” 128
Following Newton County Wildlife Association, a federal district court in North Dakota dismissed
misdemeanor MBTA criminal charges against three oil and gas companies for the incidental death
of migratory birds through contact with oil reserve pits operated by the defendants.129 In United
States v. Brigham Oil & Gas, L.P., the district court examined the plain language of the statute
and found that the word “take” was an “action word” that “involves deliberate, not accidental,
conduct. It refers to a purposeful attempt to possess wildlife through capture, not incidental or
accidental taking through lawful commercial activity.”130 The court concluded that the
use of reserve pits in commercial oil development is legal, commercially-useful activity that
stands outside the reach of the [MBTA]. Like timber harvesting, oil development and production
activities are not the sort of physical conduct engaged in by hunters and poachers, and such
activities do not fall under the prohibitions of the Migratory Bird Treaty Act.131
The court also noted that “[i]f there is a desire on the part of Congress to criminalize commercial
activity that incidentally injures migratory birds protected under the Migratory Bird Treaty Act, it
may certainly do so—but the criminal laws should be clear and certain.”132

123 Id.
124 Id.
125 Id. See “Broad Application of the Take Prohibitions in the Second and Tenth Circuits” section, supra, for discussion
of the Second Circuit cases.
126 Newton Cty. Wildlife Ass’n v. U.S. Forest Ser. 113 F.3d 110 (8th Cir. 1997). See “Cases Holding That Federal
Agency Actions Are Not Subject to MBTA Take Prohibitions” section, supra, for more information about this case.
127 Id. at 115.
128 Id.
129 United States v. Brigham Oil & Gas, L.P., 840 F. Supp. 2d 1202, 1208 (D.N.D. 2012).
130 Id. at 1209.
131 Id. at 1211.
132 Id.
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Fifth Circuit Approach Limiting Strict Liability of the Takings Prohibition
The Fifth Circuit has sought to bridge the gap between the Second and Tenth Circuit courts that
hold that incidental takings violate the MBTA as a strict liability offense, and the Eighth and
Ninth Circuit courts that hold that only direct and intentional takings, such as hunting and
poaching, violate the taking prohibition. In 2015, the Fifth Circuit in United States v. CITGO
Petroleum Corp. limited the scope of strict liability offenses under the MBTA by requiring that
takings of migratory birds be the result of an “affirmative action”—deliberate acts done directly
and intentionally to migratory birds—before being subject to the MBTA.133 In so doing, the court
reversed a criminal conviction for the death of migratory birds that flew into and died in oil
production-related tanks.134
The Fifth Circuit first confined its analysis to discerning the common law definition of “take,”
explaining that, absent other indications, Congress intends to adopt the common law definition of
statutory terms.135 The court embraced Justice Scalia’s definition of “take” as interpreted in
Babbitt v. Sweet Home Chapter Communities for Greater Oregon.136 In that case, Justice Scalia,
dissenting from the court’s holding that the prohibition on “take” under the ESA extends to
preserve habit, explained that “to ‘take,’ when applied to wild animals, means to reduce those
animals, by killing or capturing, to human control.’ . . . One does not reduce an animal to human
control accidentally or by omission; he does so affirmatively.”137 Similar to the approach of the
Eighth and Ninth Circuits, the court relied heavily on the distinction between the ESA and the
MBTA, concluding that “[h]arm and harass are the terms Congress uses when it wishes to include
negligent and unintentional acts within the definition of ‘take.’ Without these words, ‘take’
assumes its common law definition.”138
Although the court agreed with the Eighth and Ninth Circuits that “a ‘taking’ is limited to
deliberate acts done directly and intentionally to migratory birds,” the Fifth Circuit distinguished
between two types of “intent”: (1) the intentional and deliberate act (actus reus) that is
fundamental to the common law meaning of “take” and (2) the guilty mind (mens rea) element
that requires an intent to violate the MBTA.139 While acknowledging that the MBTA imposes
strict liability that does not require a mens rea element, the court explained that the
act is “to take” which, even without a mens rea, is not something that is done unknowingly
or involuntarily. Accordingly, requiring [that] defendants as an element of an MBTA
misdemeanor crime, to take an affirmative action to cause migratory bird deaths is
consistent with the imposition of strict liability.140
The court explained that a defendant must commit an “intentional and deliberate act toward the
bird” (the actus reus element) to be strictly liable under the MBTA even if the defendant has no

133 801 F.3d 477 (5th Cir. 2015).
134 Id. at 494.
135 See id. at 499 (citing United States v. Shabani, 513 U.S. 10, 13 (1995)).
136 See id. (citing Babbitt v. Sweet Home Chapter Cmtys. for a Great Or., 515 U.S. 687, 717 (1995) (Scalia, J.,
dissenting)).
137 See Babbitt, 515 U.S. at 717 (citing OXFORD ENGLISH DICTIONARY (1933); WEBSTER’S NEW INTERNATIONAL
DICTIONARY OF THE ENGLISH LANGUAGE (2d ed. 1949); Geer v. Connecticut, 161 U.S. 519, 523 (1896); 2 WILLIAM
BLACKSTONE, COMMENTARIES 411 (1766)).
138 Babbitt, 515 U.S. at 491.
139 Id. at 488-89.
140 Id. at 492.
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intention to violate the MBTA.141 The court compared a hunter who shoots a migratory bird
without a permit under the mistaken belief that the bird is not protected under the MBTA and a
person whose car accidentally collides with a bird.142 The hunter, the court explained, would be
strictly liable even though he did not intend to violate the MBTA because he engaged in an
“intentional and deliberate act toward the bird” whereas the driver’s act was not intentional and
deliberate.143
Accidental Takings of Migratory Birds
Although the courts have taken different positions on whether the incidental takings of migratory
birds are subject to the MBTA, courts have tried to exclude wholly accidental, human-related
deaths of birds—such as those caused by collisions with man-made structures, vehicles, and
communication towers—from the reach of the MBTA.144 These accidental takings differ from
other types of incidental takings (e.g., takings caused by birds flying into wind turbines) because
accidental takings are generally unforeseeable and unpreventable accidents. Although the courts
agree that the MBTA should exclude these types of accidental bird deaths, they disagree on how
to interpret the statute to limit the application of the MBTA.
In courts that hold a more expansive view of the MBTA’s taking prohibition to include incidental
takings, wholly accidental deaths still are not subject to the strict liability standard. For example,
the Second Circuit in United States v. FMC Corp. acknowledged the potentiality that a broader
interpretation of the MBTA that “would bring every killing within the statute, such as deaths
caused by automobiles, airplanes, plate glass modern office buildings or picture windows into
which birds fly, would offend reason and common sense,” but nonetheless concluded that such
situations could be handled through the “sound discretion of prosecutors and the courts.”145 The
court reasoned that a “nominal fine” and prosecutorial discretion would address such situations.146
Other courts have criticized the reasoning in United States v. FMC Corp., explaining that
“prosecutorial discretion is not a limiting principle of statutory interpretation”147 and that “proper
construction of a criminal statute cannot depend upon the good will of those who must enforce
it.”148 The U.S. District Court for the District of Colorado in United States v. Moon Lake Electric
Association suggested that requiring that an act or omission be the proximate cause of a taking is
an “important and inherent limiting feature of the MBTA’s misdemeanor provision.”149

141 Id. at 491-92.
142 Id. at 492.
143 Id.
144 See FISH & WILDLIFE SERV., THREATS TO BIRDS: MIGRATORY BIRDS MORTALITY – QUESTIONS AND ANSWERS (2016),
https://www.fws.gov/birds/bird-enthusiasts/threats-to-birds.php (listing the most common, human-caused sources of
bird mortality in North America).
145 United States v. FMC Corp., 572 F.2d 902, 905 (2d Cir. 1978) (applying strict liability for incidental bird deaths
related to pesticide manufacturing). See “Broad Application of the Take Prohibitions in the Second and Tenth Circuits”
section, supra, for discussion of this case.
146 Id. at 905.
147 See Mahler v. U.S. Forest Serv., 927 F. Supp. 1559, 1583 (S.D. Ind. 1996) (holding that the MBTA did not apply to
USFS’s planned logging during migratory nesting season because the MBTA did not apply to activities that resulted in
unintended deaths of migratory birds).
148 See United States v. Moon Lake Elec. Ass’n, Inc., 45 F. Supp. 2d 1070, 1084 (D. Colo. 1999) (holding that
application of the MBTA strict liability standard is limited by proximate causation and not prosecutorial discretion).
149 Id. at 1085.
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The Fifth Circuit in United States v. CITGO Petroleum Corp. disagreed that proximate cause was
a sufficient limitation on the strict liability standard of the MBTA, however, reasoning that under
such an interpretation of the MBTA the government could still prosecute for these types of
accidental deaths and expand the scope of the MBTA to “absurd results.”150 This expansion, the
court explained, would subject owners of glass windows, communication towers, wind turbines,
cars, cats, and “even church steeples” to the MBTA penalties upon a finding of guilt for killing a
migratory bird.151 As a result, the Fifth Circuit held that requiring an “affirmative action to cause
migratory bird deaths is consistent with the imposition of strict liability” such that a “person
whose car accidentally collided with the bird . . . has committed no act ‘taking’ the bird for which
he could be held strictly liable.”152
Judicial Interpretation of Congressional Intent
The legislative history of the MBTA supports differing interpretations of the nature and scope of
takings prohibited and types of migratory birds protected by the MBTA. The courts that have
limited the scope of the MBTA prohibitions to direct and intentional actions have interpreted the
legislative history to indicate that Congress was primarily concerned with illegal hunting and
poaching of migratory birds when it enacted the MBTA.153 Other courts have interpreted the
legislative history and statutory text to cover other types of activities that affect songbirds and
insectivorous migratory birds that are not typically hunted.154
Other courts have focused on amendments to the MBTA that added mens rea requirements for
certain types of violations. For example, the felony penalty provision in MBTA Section 6(b)
regarding the prohibition of selling migratory birds was amended in 1986 to limit application to
entities that knowingly take migratory birds to sell or barter them, or have intent to do so.155
Congress proposed this amendment to address a court decision in which the U.S. Court of
Appeals for the Sixth Circuit upheld the dismissal of a felony indictment on constitutional
grounds. Specifically, the Sixth Circuit held that strict liability application of the MBTA to the
sale of migratory birds violates the Fifth Amendment’s Due Process Clause because without a
mens rea requirement, “a person acting with a completely innocent state of mind could be

150 United States v. CITGO Petroleum Corp., 801 F.3d 477, 493-94 (5th Cir. 2015).
151 Id. at 494.
152 Id.
153 See, e.g., Seattle Audubon Soc’y v. Evans, 952 F.2d 297, 302 (9th Cir. 1991) (“The definition [of take under the
MBTA] describes physical conduct of the sort engaged in by hunters and poachers, conduct which was undoubtedly a
concern at the time of the statute’s enactment in 1918.”). See also Newton Cty. Wildlife Ass’n v. U.S. Forest Serv., 113
F.3d 110, 115 (8th Cir. 1997) (“Strict liability may be appropriate when dealing with hunters and poachers. But it
would stretch this 1918 statute far beyond the bounds of reason to construe it as an absolute criminal prohibition on
conduct, such as timber harvesting, that indirectly results in the death of migratory birds. Thus, we agree with the Ninth
Circuit that the ambiguous terms ‘take’ and ‘kill’ in 16 U.S.C. § 703 mean ‘physical conduct of the sort engaged in by
hunters and poachers, conduct which was undoubtedly a concern at the time of the statute’s enactment in 1918.’”)
(internal citations omitted).
154 See, e.g., United States v. Corbin Farm Serv., 444 F. Supp. 510, 532 (E.D. Cal. 1978) (“The use of the broad
language ‘by any means or in any manner’ [in § 703] belies the contention that Congress intended to limit the
imposition of criminal penalties to those who hunted or captured migratory birds. Moreover, a number of songbirds and
other birds not commonly hunted are protected by the conventions and so by the Act; Congress imposed criminal
penalties on those who killed these birds as well as on persons who hunted game birds. The legislative history of the
Act reveals no intention to limit the Act so that it would not apply to poisoning.”).
155 Emergency Wetlands Resources Act of 1986, P.L. 99-645, 100 Stat. 3582 (codified as amended at 16 U.S.C. §
707(b)).
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subjected to a severe penalty and grave damage to his reputation.”156 A Senate report stated that
“[n]othing in this amendment is intended to alter the ‘strict liability’ standard for misdemeanor
prosecutions under 16 U.S.C. 707(a), a standard which has been upheld in many Federal court
decisions.”157
Similarly, in 1998, Congress eliminated strict liability for taking of migratory birds by baiting in
Section 704(b) by requiring that a “person knows or reasonably should know that the area is a
baited area.”158 A Senate report explained the following:
This legislation modifies the standard of liability applicable to hunting with bait or over
baited areas. Specifically, the standard is changed from one of strict liability to one
requiring a degree of knowledge . . . . The elimination of strict liability, however, applies
only to hunting with bait or over baited areas, and is not intended in any way to reflect
upon the general application of strict liability under the MBTA [for misdemeanor offenses].
Since the MBTA was enacted in 1918, offenses under the statute have been strict liability
crimes. The only deviation from this standard was in 1986, when Congress required
scienter for felonies under the Act.159
Some courts have pointed to these amendments of the MBTA to support their determination that
MBTA prohibitions on takings are strict liability offenses. For example, in United States v.
Morgan, the Fifth Circuit upheld the conviction of a hunter who exceeded the daily bag limit of
birds allowed under applicable hunting regulations, holding that misdemeanor offenses under the
MBTA are strict liability offenses.160 In so doing, the court noted that Congress has consistently
referred to misdemeanor offenses under the MBTA as strict liability offenses.161 Similar, the Tenth
Circuit in Apollo Energies, Inc. cited the legislative history of these amendments as “further
evidence the legislative scheme invokes a lesser mental state for misdemeanor violations.”162
Congress has attempted to limit the penalty provisions of the MBTA. In June 2015, the House of
Representatives passed the FY2016 Commerce, Justice, Science, and Related Agencies
Appropriations Bill, which included an amendment sponsored by Representative Jeff Duncan that
would prohibit the use of Department of Justice funds to prosecute or hold liable any person or
corporation for a violation of the MBTA.163 The House appropriations bill was reported in the
Senate but was not brought to the floor for consideration.164
FWS Enforcement and DOI Legal Opinions on Incidental Take
Before 2017, DOI interpreted the MBTA to prohibit incidental take and kills, imposing strict
liability for activities and hazards that led to the deaths of protected migratory birds.165

156 See S. REPT. 99-645, at 16 (citing United States v. Wulff, 758 F.2d 1121 (1985)) (1986).
157 Id.
158 Migratory Bird Treaty Reform Act of 1998, P.L. 105-312, 112 Stat. 2956 (codified as amended at 16 U.S.C. §
704(b)).
159 S.Rept. 105-366, at 2-3 (1998).
160 United States v. Morgan, 311 F.3d 611, 616 (5th Cir. 2002).
161 Id. at 615.
162 United States v. Apollo Energies, Inc., 611 F.3d 679, 686 (10th Cir. 2010). See “Broad Application of the Take
Prohibitions in the Second and Tenth Circuits” section for discussion of this case.
163 H.R. 2578, 114th Cong. § 564 (2015).
164 See S.Rept. 114-66 (2015).
165 Natural Res. Def. Council v. U.S. Dep’t of the Interior, 478 F. Supp. 3d 469, 473 (S.D.N.Y. 2020) [hereinafter
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FWS enforced the prohibition on incidental take through various strategies.166 It aimed first at
achieving voluntary compliance through industry best practices guidance to minimize incidental
take of migratory birds.167
In certain instances when entities did not implement such best practices, FWS pursued
prosecution and issued fines. For example, FWS took enforcement actions against wind energy
developers to reinforce the Service’s broad interpretation that the MBTA prohibitions on taking
migratory birds extend to actions that unintentionally result in bird deaths.168 In November 2013,
Duke Energy Renewables Inc. pled guilty to violating the MBTA for the deaths of golden eagles
and other migratory birds at two wind projects that included 176 wind turbines on private land in
Wyoming.169 A year later, in December 2013, PacifiCorp Energy agreed to pay $2.5 million in
fines, restitution, and community service after pleading guilty to charges arising from 38 golden
eagle deaths and 336 other protected bird deaths at two of its wind farms in Wyoming.170
Since 2017, DOI Solicitors have issued several conflicting legal opinions regarding whether the
MBTA prohibits the incidental taking or killing of migratory birds.
During the Obama Administration in January 2017, then-DOI Solicitor Hilary Tompkins issued a
legal opinion, M-37041 (the Tompkins Opinion), concluding that:
[The] MBTA’s broad prohibition on taking and killing migratory birds by any means and
in any manner includes incidental taking and killing. . . . The MBTA imposes strict liability

NRDC].
166 Id.
167 Id. See also FWS, BEST PRACTICES, at https://www.fws.gov/birds/management/project-assessment-tools-and-
guidance/guidance-documents.php (last visited Jan. 20, 2022) (listing activity-specific voluntary best practices to
reduce impacts to migratory birds).
168 FWS estimates that wind turbines may kill half a million birds a year. FISH & WILDLIFE SERV., WILDLIFE CONCERNS
ASSOCIATED WITH WIND ENERGY DEVELOPMENT (2015), at https://www.fws.gov/Midwest/wind/wildlifeimpacts/
index.html [hereinafter WILDLIFE CONCERNS]. In an effort to reduce these deaths, FWS issued the Land-Based Wind
Energy Guidelines on March 23, 2012. FISH & WILDLIFE SERV., U.S. FISH AND WILDLIFE SERVICE LAND-BASED WIND
ENERGY GUIDELINES (2012), at https://www.fws.gov/ecological-services/es-library/pdfs/WEG_final.pdf. However, the
Service makes clear that adherence to the guidance does not “absolve” individuals or companies from MBTA
violations for taking or killing protected migratory birds. WILDLIFE CONCERNS. FWS indicates that it would use its
enforcement discretion to focus on investigating and prosecuting those who harm or kill migratory birds without taking
steps to avoid the take (i.e., those who do not adhere to the guidance). Id.
169 Press Release, Dept. of Justice, Utility Company Sentenced in Wyoming for Killing Protected Birds at Wind
Projects (November 22, 2013), at https://www.justice.gov/opa/pr/utility-company-sentenced-wyoming-killing-
protected-birds-wind-projects. According to the charges presented in court, Duke Energy Renewables Inc. failed to
make all reasonable efforts to build the projects in a way that would avoid the risk of avian deaths by collision with
turbine blades, despite prior warnings about this issue from FWS. Id. Under a plea agreement with the government, the
company agreed to pay fines, restitution, and community service totaling $1 million and was placed on probation for
five years. Id. The Department of Justice stated that this “case represents the first criminal conviction under the
Migratory Bird Treaty Act for unlawful avian takings at wind projects.” Id.
170 Press Release, Dept. of Justice, Utility Company Sentenced in Wyoming for Killing Protected Birds at Wind
Projects (December 19, 2014), at https://www.justice.gov/opa/pr/utility-company-sentenced-wyoming-killing-
protected-birds-wind-projects-0. PacifiCorp pled guilty to two misdemeanor violations of the MBTA and was
sentenced to five years’ probation. Id. The company also agreed to institute a compliance program to prevent bird
deaths at the utility’s four commercial wind farms in Wyoming. Id. Similar to Duke Energy case, the charges alleged
that the company failed to make all reasonable efforts to build projects in a way that would avoid risk of bird deaths by
collision with turbine blades consistent with the guidance finalized by the FWS in 2012. Id. Wyoming, where these
enforcement cases were filed, is within the Tenth Circuit. It may be more difficult to prosecute wind energy developers
for incidental take in the Fifth, Eighth, and Ninth Circuits, where the courts have held that the MBTA applies to actions
(like hunting) directed against migratory birds, and not to the unintended effects of commercial activities, such as wind
energy projects. See discussions, infra.
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(with narrow exceptions) for misdemeanor violations resulting from unauthorized take,
incidental or otherwise. Therefore, the government need not show that a defendant willfully
or intentionally took or killed birds to prove a violation of the MBTA.171
The opinion asserted that the statutory terms “take” and “kill” “by any means or matter” in the
MBTA Section 2(a) prohibitions are “sufficiently broad to encompass actions performed
knowingly, negligently, or without any knowledge of wrongdoing.”172 This interpretation noted
that “take that is incidental to industrial or commercial activities” would violate the MBTA.173
To reach this conclusion, the Tompkins Opinion relied, in part, on the legislative history of
amendments that added mens rea requirements for violations of other MBTA provisions discussed
above. The Tompkins Opinion asserted that the legislative history of these amendments to the
MBTA “demonstrates that multiple subsequent Congresses understood, and reaffirmed, that the
MBTA was a strict-liability statute,” meaning that no “particular mental state is required for a
[misdemeanor] violation to occur.”174 The opinion also highlighted the Tenth Circuit’s opinion in
Apollo Energies, the Second Circuit’s opinion in FMC Corp., and other similar cases that held
that the “prohibitions of ‘take’ and ‘kill’ unambiguously apply on a strict-liability basis (except in
the context of felony prosecutions and baiting cases) and to incidental take.”175
During the Trump Administration, DOI issued a different legal interpretation of the MBTA’s
application to incidental takings. In December 2017, then-Principal Deputy Solicitor, Daniel
Jorjani, replaced the Tompkins Opinion with a new legal opinion, M-37050 (the Jorjani
Opinion).176 That opinion concluded that the MBTA “prohibitions on pursuing, hunting, taking,
capturing, killing, or attempting to do the same apply only to affirmative actions that have as their
purpose the taking or killing of migratory birds, their nests, or their eggs.”177 The Jorjani Opinion
explained that the MBTA’s strict liability provisions are not triggered until there is a deliberate act
(the actus reus) to take a migratory bird.178 To support its conclusion, the Jorjani Opinion relied,
in part, on the Fifth Circuit in CITGO, discussed above, and other similar cases. The opinion also
noted that the legislative history of amendments that added mens rea requirements for violations
were not related to MBTA Section 2(a) take prohibitions. On February 3, 2020, FWS proposed
regulations to codify its interpretation on incidental take.179
The Trump Administration’s interpretation spawned further judicial and regulatory actions. On
August 11, 2020, a federal district court in Natural Resources Defense Council v. DOI (NRDC)
vacated the Jorjani Opinion.180 The court held that the plain language of the MBTA’s prohibition
on taking protected migratory birds “at any time, by any means, and in any manner” means that
the MBTA prohibits incidental killing of the birds.181 The court rejected DOI’s argument that the

171 Opinion M-37041 at 2.
172 Opinion M-37041 at 8.
173 Opinion M-37041.
174 Opinion M-37041 at 9, 12.
175 Opinion M-37041 at 23-30.
176 Opinion M-37050.
177 Opinion M-37050 at 2.
178 See Opinion M-37050 at 22-23 (asserting that the deliberate acts (e.g., to take or kill) prohibited by the MBTA “are
purposeful and voluntary affirmative acts directed at reducing an animal to human control, such as when a hunter
shoots a protected bird causing its death”).
179 Regulations Governing Take of Migratory Birds, 85 Fed. Reg. 5915 (Feb. 3, 2020).
180 Natural Res. Def. Council v. U.S. Dep’t of the Interior, 478 F. Supp. 3d 469 (S.D.N.Y. 2020) [hereinafter NRDC].
181 Id. at 481.
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Jorjani Opinion interprets only the actus reus of the take prohibitions by limiting its coverage to
activities that are “directed at” birds, and thus does not impose a mens rea requirement. The court
concluded that “[t]here is nothing in the text of the MBTA that suggests that in order to fall within
its prohibition, activity must be directed specifically at birds.”182 Despite the court’s decision,
FWS finalized its proposed rule on January 7, 2021, codifying its interpretation of incidental take
from M-37050.183 In the preamble, FWS explained that it disagreed with the district court’s
decision in NRDC and that the Jorjani Opinion is consistent with the Fifth Circuit’s decision in
CITGO.184 The final rule was to go into effect on February 8, 2021.185
Since the beginning of the Biden Administration, FWS proceeded with multiple actions to reverse
the Trump Administration’s interpretation and regulations regarding incidental take of migratory
birds. After delaying the effective date of the January 7, 2021 rule,186 FWS revoked it in a rule
published on October 4, 2021, effectively reinstating its prior interpretation that the MBTA
prohibits incidental take.187 FWS explained that its interpretation is consistent with the NRDC
decision and its previous practice of applying enforcement discretion in incidental take
circumstances.188
Soon after, FWS issued Director’s Order No. 225 to the Service on how to implement its current
position on incidental take, and to clarify its related enforcement policies.189 The order announced
plans to prioritize enforcement against incidental take from an otherwise illegal activity, or
foreseeable incidental take from legal activities that occur because regulated entities did not
implement “beneficial practices” to avoid or minimize incidental take.190 The order referenced
best practices that FWS has developed for specific structures (e.g., communication towers and
electric utility lines) and industries (e.g., oil and gas and wind energy).191 The order also directs
Service employees to avoid or minimize take in their own activities.192 The order went in to effect
on December 3, 2021.
FWS also published an advanced noticed of proposed rulemaking (ANPR) to gather comments
and information for future rulemakings on incidental take prohibitions under the MBTA.193 FWS
plans to codify its interpretation of the MBTA as prohibiting incidental take, instead of relying on
enforcement discretion.194 FWS is also considering authorizing certain types of incidental take

182 Id. at 487-88.
183 Regulations Governing Take of Migratory Birds, 86 Fed. Reg. 1134 (Jan. 7, 2021).
184 86 Fed. Reg. at 1134.
185 Id. The decision in NRDC to vacate the Jorjani Opinion did not directly affect DOI’s proposed rule, even though the
subject matter was related, because the rule was a different agency action. When the rule became final on January 7,
2021, it also became subject to separate judicial review. As this section discusses, however, it appears that the January
7, 2021, rule may be superseded by subsequent agency action.
186 Regulations Governing Take of Migratory Birds; Delay of Effective Date, 86 Fed. Reg. 8715 (Feb. 9, 2021).
187 Regulations Governing Take of Migratory Birds; Revocation of Provisions, 86 Fed. Reg. 54,642 (Oct. 4, 2021).
188 Id.
189 FWS, Director’s Order No. 225, Incidental Take of Migratory Birds (Oct. 5, 2021), at
https://www.fws.gov/regulations/mbta/sites/default/files/2021-09/Final_MBTA_Directors_Order.pdf.
190 Id. at 2-3.
191 Id. at 3.
192 Id.
193 Migratory Bird Permits; Authorizing the Incidental Take of Migratory Birds; Advance Notice of Proposed
Rulemaking; Notice of Intent to Prepare a National Environmental Policy Act Document, 86 Fed. Reg. 54,667 (Oct. 4,
2021).
194 86 Fed. Reg. at 54,668-69.
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using a combination of three regulatory tools: (1) exceptions to the MBTA’s prohibition on
incidental take; (2) general permits for certain activity types; and (3) individual permits.195
Exceptions could include noncommercial activities by individuals (e.g., homeowner activities that
take birds) and certain commercial activities where beneficial practices or technologies
sufficiently avoid and minimize incidental take.196 FWS could also authorize general permit
programs for specific activities through a registration system, which would not require a separate
environmental review for each registration.197 By contrast, individual permits would be similar to
current depredation permit regulations and would include customized permit conditions.198 FWS
noted that it plans to use the information gathered from the ANPR to help prepare a draft
environmental review as required by the National Environmental Policy Act.199 FWS received
over 11,000 comments on its ANPR by the close of the comment period on December 3, 2021.200
Considerations for Congress
FWS has recognized what some view as the importance of providing regulatory certainty to
regulated entities while balancing statutory and treaty obligations for the long-term conservation
of migratory birds.201 For example, wind-energy developers often desire direction on how to
address incidental taking of migratory birds protected under the MBTA as wind energy continues
to be a fast-growing source of new electric power generation.202
The legal debate regarding the scope of the MBTA’s take prohibitions and its application to
incidental take will likely continue absent direction from the Supreme Court or Congress. Some
Members of Congress have introduced legislation in the 117th Congress to clarify that the MBTA
prohibitions apply to incidental take. H.R. 4833 would amend MBTA Section 2(a) to prohibit
incidental take of migratory birds.203 The bill would also establish a new section of the MBTA to
clarify that any person who incidentally takes a migratory bird as a result of a commercial activity
would violate the MBTA unless authorized by a general permit or other listed exceptions in the
bill.204

195 Id. at 54,669.
196 Id.
197 Id.
198 See id. (referring to depredation permitting regulations in 50 C.F.R. part 21, subpart C).
199 Id. at 54,670. In 2015, FWS published a notice of intent to establish an incidental take permit program for the
MBTA, but it was never finalized. See Migratory Bird Permits; Programmatic Environmental Impact Statement; Notice
of Intent, 80 Fed. Reg. 30,032 (May 26, 2015).
200 See Docket FWS-HQ-MB-2021-0105, at https://www.regulations.gov/docket/FWS-HQ-MB-2021-0105/comments.
201 86 Fed. Reg. at 54,668.
202 For information regarding the development of wind energy sources, see CRS Report R40175, Wind Energy:
Offshore Permitting, by Adam Vann and CRS Report R46970, Offshore Wind Energy: Federal Leasing, Permitting,
Deployment, and Revenues, by Laura B. Comay and Corrie E. Clark.
203 H.R. 4833, 117th Cong. (2021).
204 H.R. 4833, 117th Cong. § 2(b) (2021).
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Author Information

Linda Tsang
Erin H. Ward
Legislative Attorney
Legislative Attorney

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