Injurious Species Listings Under the Lacey Act: A Legal Briefing

Injurious Species Listings Under the Lacey Act: A Legal Briefing

Injurious Species Listings Under the
Lacey Act: A Legal Briefing
Kristina Alexander
Legislative Attorney
August 1, 2013
Congressional Research Service
7-5700
www.crs.gov
R43170

Injurious Species Listings Under the Lacey Act: A Legal Briefing

Summary
The Lacey Act addresses illegal wildlife trade to protect species at risk and bars importing species
found to be injurious to the United States. The portion of the Lacey Act known as the injurious
species provision is codified in the criminal code at 18 U.S.C. Section 42 rather than with the
trade provision of the Lacey Act, which is codified in the conservation title, Title 16. Two bills
before Congress, H.R. 996/S. 1153, address the effectiveness of the act, proposing deadlines to
the regulatory process of adding injurious species. However, other issues, such as whether the act
is effective at constricting the spread of unintended imports, such as mussels, remain.
Under the injurious species provision, it is illegal to import or ship between states any species
listed under the act. The statute bans import and shipment of living creatures and their eggs,
although the regulations also ban certain dead fish. Permits may be issued to import banned
species for scientific, zoological, educational, or medical purposes. A violation is a Class B
misdemeanor, punishable by no more than six months in jail and/or up to a $5,000 fine for an
individual, $10,000 for an organization.
The list of banned species may be amended either by statute or by regulation issued by the Fish
and Wildlife Service (FWS) of the Department of the Interior. In 1900, the list contained four
species. Now it contains dozens, with most being added by regulation. Most recently, in March
2012, four python and an anaconda species were added to the list. In light of that addition, the
113th Congress is considering H.R. 2158, which would exempt certain snake export activities
from the trade provisions of the Lacey Act to allow retailers to export listed snakes without
violating the law. Also, Congress is considering adding the quagga mussel (Dreissena
rostriformis) to the list of banned species (H.R. 1823).
The act does not authorize agencies to take any measures against injurious species already present
in the United States unless part of interstate commerce, so once a species has entered the country,
it may flourish. For example, in 1900 the Lacey Act prohibited importing English sparrows or
starlings, yet populations of both prospered, and Congress removed the two species from the list
in 1960 because of the futility of regulating them. Similarly, the 1990 listing of the zebra mussel
appears to have done nothing to prevent the spread of the invasive species—likely because the
species was never intentionally imported. The Eurasian mussel entered through the ballast water
emptied into the Great Lakes and has moved to neighboring waterways. It made its way to
nonconnected waterways by being transported on the hulls of commercial and recreational boats.
The quagga mussel took the same route, and now is found as far west as Lake Mead, Nevada.
The regulation of invasive mussels has proved controversial, with FWS indicating that water
transports between Oklahoma and Texas were in violation of the Lacey Act because zebra
mussels would be moved across state lines with the water. The 112th Congress exempted those
water transfers from the Lacey Act in P.L. 112-237, Section 5. If quagga mussels were banned,
more interstate water transfers might be subject to Lacey Act enforcement. However, there is a
legal question as to whether FWS’s interpretation of the injurious species ban properly extends to
transport, rather than only to import and shipment, as stated by the law.

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Injurious Species Listings Under the Lacey Act: A Legal Briefing

Contents
Introduction ...................................................................................................................................... 1
Background and History of the Lacey Act Injurious Species Provision .......................................... 4
Prohibited Acts .......................................................................................................................... 4
White List v. Black List ....................................................................................................... 4
Import or Shipment ............................................................................................................. 5
Exceptions ................................................................................................................................. 7
Penalties ..................................................................................................................................... 7
Regulatory Listing Process .............................................................................................................. 8
Rulemaking................................................................................................................................ 8
Criteria for Finding Injurious Species ..................................................................................... 10
Shared Listing Authority ......................................................................................................... 10
Legal Issues Before Congress ........................................................................................................ 13
Did Congress Ban Transport as Well as Shipment? ................................................................ 13
Limits on Law’s Effectiveness ................................................................................................ 16
Creature Limits ........................................................................................................................ 17
Taxonomic Consistency .................................................................................................... 17

Figures
Figure 1. Scaled Representation of Black-Listed Species ............................................................... 3

Appendixes
Appendix A. Injurious Species ...................................................................................................... 19
Appendix B. FWS Criteria for Making an Injurious Species Determination ................................ 23

Contacts
Author Contact Information........................................................................................................... 25
Acknowledgments ......................................................................................................................... 25

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Injurious Species Listings Under the Lacey Act: A Legal Briefing

Introduction
The 1900 Lacey Act prohibited importing four species that Congress found injurious to the
agricultural and horticultural interests of the United States: the mongoose, fruit bat, English
sparrow, and starling.1 That portion of the Lacey Act, known as the injurious species provision,
has been amended several times, and is codified in the criminal code, 18 U.S.C. Section 42. The
trade provisions of the Lacey Act, which restrict the trade of species protected by other laws, are
codified in the conservation title, Title 16, and are not reviewed herein.2 As Congress considers
H.R. 996/S. 1153, issues, such as the act’s effectiveness in blocking the spread of species that are
well-established at the time of being listed, may arise.
The injurious species provision prohibits “the importation into the United States ... or any
shipment between [the States]” of any listed animals, their offspring, or eggs.3 Some exceptions
are allowed. For example, permits may be issued for importing creatures for “zoological,
educational, medical, and scientific purposes.”4
The act is enforced by the Fish and Wildlife Service (FWS) of the Department of the Interior and
the Customs Service and Border Protection (Customs Service) of the Department of Homeland
Security. Violations are a Class B misdemeanor with a maximum jail time of six months and/or a
maximum penalty of $5,000 for an individual or $10,000 for an organization.
Animals may be added to the list, which now totals dozens of species (some listed by genus or
family), by congressional amendment or by regulatory action.5 Most animals added since 1900
have been added by regulation. (See Appendix A.) The regulatory listing process, however, has
taken up to six years. Congress is considering legislation to alter the regulatory process, because
delays can give species a chance to become well-established, making eradication difficult if not
impossible. H.R. 996/S. 1153 would direct FWS to make quicker regulatory listings. Another bill,
H.R. 1823, would add the quagga mussel (Dreissena rostriformis) to the injurious species list.
Constrictor snakes banned by the Lacey Act are addressed in H.R. 2158, which would exempt
exporting python and anaconda species from the definition of interstate commerce under the trade
provisions of the Lacey Act, but does not address the shipping ban under 18 U.S.C. Section 42.
The act’s success in preventing the spread of injurious species is under review. For example,
when reviewing H.R. 1823, Congress may weigh the appropriateness of regulating accidental
imports, such as quagga mussels, as a criminal offense, or consider whether the act is suitable to

1 31 Stat. 188 (1900).
2 For information on the trade provisions of the Lacey Act, see CRS Report R42067, The Lacey Act: Protecting the
Environment by Restricting Trade, by Kristina Alexander. To focus on plant issues, see CRS Report R42119, The
Lacey Act: Compliance Issues Related to Importing Plants and Plant Products, by Pervaze A. Sheikh.
3 18 U.S.C. §42(a)(1).
4 18 U.S.C. §42(a)(3). Also, import and shipment of domesticated canaries, parrots, and all psittacine birds are not
restricted. 18 U.S.C. §42(a)(4). For a discussion on invasive species in general, see CRS Report RL30123, Invasive
Non-Native Species: Background and Issues for Congress, by M. Lynne Corn et al., which references other laws
pertaining to invasive species.
5 A House report on the North Zebra Mussel Barrier Act of 2012 (H.R. 6007) states there are 236 species on the
injurious species list. H.Rept. 112-657 (September 10, 2012). That number was provided to Congress by FWS, which is
revising its total to more than 400 species, in large part due to listing the entire family Salmonidae. E-mail from Susan
Jewell, FWS Injurious Wildlife Listing Coordinator, to the author (July 10, 2013).
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

prevent anything other than intentional imports. The act’s origins indicate that Congress intended
to require proof of knowledge to convict a carrier or the recipient, known as a consignee, rather
than to impose a strict liability standard. (See “Penalties” below.)
Another point of interest is whether FWS has appropriately interpreted the law as applying to any
form of interstate transportation, including water piped between states. In 2012, in response to
FWS action alleging illegal transport of zebra mussels in water pumped from Lake Texoma in
Oklahoma to Texas, Congress acted to prevent the injurious species provision from applying (P.L.
112-237, §5). No court has considered the issue, but the legislative history suggests that, contrary
to FWS’s current interpretation, only import and shipping are violations of the act, rather than all
forms of interstate movement. A court would have to decide whether the FWS interpretation is
subject to appropriate deference. However, the interpretation that the act provides otherwise is
bolstered by the plain language of the statute, which bars “importation into [the United States or
its territories] or any shipment between [the states],” but also explicitly punishes the “importer or
consignee” by destroying the prohibited species at their expense.6 Additionally, the 100-plus-year
legislative history of this act consistently uses shipment or common carrier, when referencing
injurious species, but uses transport only when prohibiting Lacey Act trade activities, which were
segregated from Title 18 in 1981.7 If interpreted strictly as described above, the injurious species
provision would be weakened because it would restrict enforcement actions to those involving
import or commercial shipping.

6 18 U.S.C. §42(a)(1).
7 95 Stat. 1079.
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

Figure 1. Scaled Representation of Black-Listed Species
Sizes represent the number of species listed as injurious

Source: Congressional Research Service based on 50 C.F.R. Part 16.
Notes: Fish size is based on estimated 55 domestic salmon and trout species of the family Salmonidae, but not al
of the hundreds of species within the family. It also includes 34 species of the snakehead genera Channa and
Parachanna, and 4 species of Asian carp. 50 C.F.R. §16.13. Both Snake and Bird sizes include named subspecies. 50
C.F.R. §16.15 and 50 C.F.R. §16.12, respectively.
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Background and History of the
Lacey Act Injurious Species Provision
This report examines the Lacey Act provision that directs injurious species bans and is codified in
the criminal code, Title 18.8 The injurious species provision addresses prohibited acts, exceptions,
and penalties.
Prohibited Acts
The injurious species prohibitions consist of a list of banned species and restrictions on the import
and shipment of those species.
White List v. Black List
In 1900, the original Lacey Act injurious species provision had two sections restricting such
imports. The first forbade import of “any foreign wild animal or bird” absent a special permit
issued by the Department of Agriculture.9 The second prohibited importing “the mongoose, the
so-called ‘flying foxes’ or fruit bats, the English sparrow, [and] the starling.”10 The Member for
whom the act is named, Representative John F. Lacey of Iowa, urged passage of the law to avoid
another environmental disaster like the introduction of the sparrow, which he called “the ‘rat of
the air,’ that vermin of the atmosphere.”11 He said that the ban on imports was necessary because
“There is a compensation in the distribution of plants, birds, and animals by the God of nature.
Man’s attempt to change and interfere often leads to serious results.”12
Generally, laws that list banned species are known as “black list” laws. “White list” laws ban
importing all species except those on an approved list. For decades, the Lacey Act was primarily a
white list law—prohibiting importing “any foreign wild animal or bird” except under special
permit, as well as banning all imports of the four species mentioned above.13
The 1949 amendments of the Lacey Act transformed the injurious species provision into a purely
black list law, by excising the language that barred import of “any foreign wild animal or bird.”14
Instead, only listed species were banned, which included just the original four: mongoose, fruit
bats, sparrows, and starlings.15

8 18 U.S.C. §42(a)(1).
9 31 Stat. 188, §2. In 1939, authority over the injurious species provision was transferred to the Department of the
Interior. 53 Stat. 1433.
10 31 Stat. 188.
11 Congressional Record—House, at 4871 (April 30, 1900).
12 56 Cong. Rec. 4871 (April 30, 1900).
13 31 Stat. 188.
14 63 Stat. 89.
15 The 1949 amendments also added language prohibiting “transport[] [of wild animals and birds] under inhumane and
unhealthful conditions.” 63 Stat. 89. While this section remains codified with the injurious species provision, in 18
U.S.C. Section 42(c), it is not part of the ban on injurious species and is outside the scope of this report.
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

The 1960 amendment to the injurious species provision of the Lacey Act addressed scientific
concerns. It added scientific names for the mongoose and fruit bats, and stated that the ban
applied not just to “animals and birds” but to mammals, birds, “fish (including mollusk and
crustacea), amphibians, [and] reptiles.”16 The English sparrow and the starling were removed
from the list. A Senate report discussed the removal: “We believe that no useful purpose would be
served by continuing the specific prohibition against their importation. From introductions into
this country prior to 1900, these birds have extended their range throughout the country and no
feasible means for controlling their numbers or range has been devised.”17
The 1960 amendment also established that in addition to barring species that imperiled
agricultural and horticultural interests, the FWS could ban species that would harm forestry,
wildlife, and wildlife interests within the United States.18 The 1960 version of the injurious
species provision remains the framework for the current law.
Subsequent amendments have added species without changing the substance of the law:
• In 1990, the zebra mussel;19
• In 1991, the brown tree snake;20 and
• In 2010, the bighead carp.21
No species have been removed from the list by statute since 1960.22
Import or Shipment
The Lacey Act injurious species provision has always restricted import of banned species. While
it currently also prohibits interstate shipment of those animals, the language regarding shipping
has changed over the act’s 113-year history. Because the injurious species provision and the trade
provision were codified together until 1981, the amendments to the shipping provision of the
injurious species provision relate to changes in the trade provision.

16 74 Stat. 753. While the pre-1960 version separated birds from the animal kingdom, the current language completely
omits insects, which comprise a heavy majority of all species on the planet. 18 U.S.C. §42(a)(1).
17 S. Rpt. 86-1883, Importation of Injurious Mammals, Etc., Committee on the Judiciary (August 20, 1960).
18 74 Stat. 753.
19 104 Stat. 4772. For a summary of the spread of zebra mussels, see U.S. Geological Survey, http://nas.er.usgs.gov/
queries/factsheet.aspx?speciesid=5.
20 105 Stat. 1901. The December 1991 statute added the brown tree snake to the injurious species provision more than a
year after the snake was listed via regulation effective May 25, 1990. 55 Fed. Reg. 17441 (April 25, 1990).
21 124 Stat. 3282.
22 A regulation in 1965 effectively delisted the European hare by changing how it and the European rabbit were
identified. Originally, the two species’ common and scientific names were given. 39 Fed. Reg. 1169 (August 13, 1952).
The 1965 regulation instead worded the ban as follows: “any species of European rabbit of the genus Oryctolagus.” 30
Fed. Reg. 9641 (August 3, 1965). However, the genus Oryctolagus does not include the species known as the European
hare. See Integrated Taxonomic Information System (ITIS), online at http://www.itis.gov/servlet/SingleRpt/SingleRpt.
There is no indication whether the delisting was intentional.
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

For decades the Lacey Act prohibited two types of acts related to injurious species in two separate
provisions: import, in the injurious species provision; and acts related to a carrier for shipping, in
the trade provision. In the 1900 act, the injurious species provision, then known as Section 2, only
prohibited import. Section 3 of the 1900 act, which became the trade portion of the Lacey Act,
referenced the ban on injurious imports, prohibiting:
deliver[y] to any common carrier, or for any common carrier to transport ... any foreign
animals or birds the importation of which is prohibited.... ” (emphasis supplied).23
In essence, importing banned species was illegal, as was shipping those species by a common
carrier. Section 2 of the 1900 act eventually was codified in 18 U.S.C. Section 42. Section 3 of
the 1900 act was codified in 18 U.S.C. Section 43, before being moved to the conservation title.
The import ban was retained in the 1909 amendment, which slightly altered the shipping
language in the trade provision as follows: “It shall be unlawful for any person to deliver to any
common carrier for transportation, or for any common carrier to transport ... any foreign animals
or birds, the importation of which is prohibited.... ”24
In 1948, the injurious species provision, codified in Section 42, continued to bar importing those
species.25 The trade provision, however, was modified, removing from Section 43 the language
that expressly banned delivering illegal imports, which included the import of injurious species,
to common carriers.26 As a result of Section 43 no longer applying to illegal imports, the Section
42 ban on importing became the only prohibition regarding injurious species.
The 1949 amendment did not change the prohibitions from the previous year, meaning that
importing was the only prohibited act within the injurious species provision.27
The 1960 amendment established the framework of the current version.28 The invasive species
provision prohibits “the importation into” or “any shipment between” the United States and its
territories and possessions. Shipment is just one of many banned activities in the trade provisions
of the 1960 amendments: delivery, carrying, transporting, shipping by any means, or knowingly
receiving for shipment.29 Because shipment is listed with transport in the trade provision, this
suggests that Congress perceived them as two distinct activities at the time of the 1960
amendments. For more discussion on this, see “Did Congress Ban Transport as Well as
Shipment?”, below.

23 31 Stat. 188.
24 35 Stat. 1137.
25 62 Stat. 687.
26 Instead, the section made it a crime to “deliver[] or knowingly receive[] for shipment, transportation or carriage in
interstate or foreign commerce, any wild animal or bird ... imported from any foreign country” if taken contrary to
federal, state, or foreign law. 62 Stat. 687.
27 The 1949 amendment added new language barring “transportation [of animals] to the United States, or any Territory
or district thereof under inhumane or unhealthful conditions.” 63 Stat. 89. This section became 18 U.S.C. Section 42(c)
of the Lacey Act, but is not analyzed in this report.
28 74 Stat. 754.
29 74 Stat. 754.
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In 1981, the trade provision was codified under Title 16.30 Subsequent amendments have not
changed the prohibited acts under the injurious species provision.31
Exceptions
While the original Lacey Act injurious species provision prohibited importing “any foreign wild
animal or bird except under special permit,”32 an exception existed for “museums or scientific
collections” and for “certain cage birds, such as domesticated canaries, parrots, or such other
species” as might be designated.33 The exceptions were necessary because, prior to the 1949
amendment, the injurious species provision banned all foreign animals from import unless
specifically permitted by the U.S. government.
The exceptions did not change until the 1960 amendment, which expanded the exception for
importing black-listed species for “natural history specimens for museums or scientific
collections” to allow exceptions found to be protective of the public interest and health for the
import of “zoological, educational, medical, and scientific purposes of any mammals, birds, fish
(including mollusks and crustacea), amphibia, and reptiles, or the offspring or eggs thereof, where
such importation would be prohibited otherwise.... ”34
The other change in 1960 was slight, adding “all other species of psittacine birds” to the
description of the cage birds that may be brought into the country.35 However, it is not clear why
this was needed since the 1949 amendment had changed the injurious species provision to a black
list law and had, consequently, eliminated the blanket ban on “any foreign wild animal or bird.”
With a black list, it is not clear why there needs to be an exception for birds that are not on the
black list.
Penalties
Until 1960, the prohibited acts of importing and shipping had separate penalty provisions. The
1900 law provided that any species imported contrary to the injurious species provision shall “be
destroyed or returned at the expense of the owner.”36 The 1909 version also provided for return or
destruction of the injurious species.37 Additionally, the trade provision was amended to include
penalties for injurious species imports, fining the shipper, consignee, and carrier up to $200.38

30 See the Lacey Act Amendments of 1981, P.L. 97-79; 95 Stat. 1079.
31 18 U.S.C. §42(a)(1).
32 31 Stat. 188.
33 Id.
34 74 Stat. 754 §3; 18 U.S.C. §42(a)(3).
35 74 Stat. 754.
36 31 Stat. 188.
37 35 Stat. 1137.
38 35 Stat. 1138. Conviction of the consignee or carrier required showing a knowing violation.
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

In 1935, the fine was raised and jail time was added. The law penalized the shipper, carrier, or the
consignee up to $1,000 for trade violations, but knowing violations had to be proved against the
carrier and the consignee.39 In addition to, or instead of the fine, imprisonment of up to six
months was authorized.40 It left in place the injurious species language requiring the destruction
or return of any injurious species upon arrival “at the expense of the owner.”41
Congress reduced the fine to $500 in 1948, but left the jail time the same.42 A subsequent
amendment in 1949 left the provision untouched, but the language requiring destruction of the
illegally imported species was modified in 1960.43 Until 1960, the act provided that the export or
destruction of the contraband would be at the expense of the owner.44 But the 1960 amendment
added “or consignee,” which may tacitly acknowledge both the revision of prohibited acts to
include shipping and/or that the recipient was not immune from prosecution.45 The 1960
amendments are still in place, although due to the Alternative Fines Act, the current penalty is a
maximum of $5,000 for an individual and $10,000 for an organization.46
Regulatory Listing Process
Rulemaking
The act has always allowed an agency to designate species as injurious and bar their import.
Originally the Department of Agriculture was the authorized agency, but in 1939 the regulatory
authority was transferred to the Department of the Interior.47 The regulatory listing is conducted
via informal rulemaking under the Administrative Procedure Act (APA).48 The listing process can
be petitioned by a third party or by the agency.49 If FWS decides to pursue listing, it issues a
proposed rule, and then upon receiving and evaluating public comments, issues a final rule.50

39 49 Stat. 381. According to the Consumer Price Index inflation calculator, $1,000 in 1935 had the same buying power
as $17,003 in 2013. See http://www.bls.gov/data/inflation_calculator.htm.
40 49 Stat. 381.
41 Id.
42 62 Stat. 687.
43 74 Stat. 754.
44 62 Stat. 687.
45 74 Stat. 754, §1; 18 U.S.C. §42(a)(1).
46 18 U.S.C. §3359(a)(7) (establishing that crimes with sentences of at least 30 days but not more than six months were
Class B misdemeanors); and 18 U.S.C. §3371(b)(6) (establishing the maximum fines for Class B misdemeanors).
47 53 Stat. 1433.
48 5 U.S.C. §553.
49 See generally, FWS Injurious Species listing process, http://www.fws.gov/injuriouswildlife/pdf_files/
InjuriousWildlifeEvaluationProcessFlowChart.pdf.
50 Id.
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In addition to complying with the APA, the
APA Rulemaking: In Brief51
rulemaking must also comply with the
National Environmental Policy Act (NEPA),
The APA requires agencies to provide the public with
adequate notice of a proposed rule fol owed by a
which requires an agency to consider the
meaningful opportunity to comment on the rule’s
impacts of proposed major actions on the
content.52 The adequate notice requirement is generally
environment, and, if significant, prepare an
achieved by publishing a notice of proposed rulemaking
environmental impact statement.58 FWS must
in the Federal Register.53
also consider the listing in the context of
Once adequate notice is provided, the agency must
Executive Order No. 1286659 and other
provide interested persons with a meaningful
mandates directing regulatory efficiency.
opportunity to comment on the proposed rule.54 While
there is no minimum period of time for a comment
period, courts have focused on whether the agency
To promote more efficient decisions, FWS is
provided an “adequate” opportunity to comment—the
proposing to establish a categorical exclusion
length of the comment period is only one factor.55
for injurious species regulatory listings under
Once the comment period has closed, the agency must
NEPA.60 A categorical exclusion (CE) obviates
consider the relevant information and incorporate a basis
the need to conduct an environmental review
and purpose into the adopted rule.56 The final rule must
of the action under NEPA, barring
be published in the Federal Register not less than 30 days
extraordinary circumstances.61
before the rule’s effective date.57
Dozens of species are on the black list, most of which were added by regulation. The first
rulemaking occurred in 1952, banning mynahs and starlings, as well as European rabbits and
European hares.62 The most recent rulemaking added four python and one anaconda species.63
Use of taxonomy on the black list is inconsistent. Animals are banned at the family, genus,
species, and/or subspecies levels. For more on the legal inconsistencies with taxonomy, see
“Taxonomic Consistency,” below. A list of injurious species and the regulatory listing history
prepared by FWS is available at Appendix A.

51 For more on the APA, see CRS Report R41546, A Brief Overview of Rulemaking and Judicial Review, by Todd
Garvey and Daniel T. Shedd. This information is excerpted from their report.
52 5 U.S.C. §553(b)-(c).
53 5 U.S.C. §553(b).
54 5 U.S.C. §553(c).
55 Jeffrey S. Lubbers, A Guide to Federal Agency Rulemaking, p. 296 (4th ed. 2006) (citing Fla. Power & Light Co. v.
United States, 846 F.2d 765, 772 (D.C. Cir. 1988)). However, Executive Order 12866, which provides for presidential
review of agency rulemaking, states that the public’s opportunity to comment, “in most cases should include a
comment period of not less than 60 days.” Exec. Order No. 12866, §6(a); 58 Fed. Reg. 51735 (October 4, 1993).
56 5 U.S.C. §553(c).
57 Some exceptions exist. See 5 U.S.C. §553(d).
58 42 U.S.C. §4332.
59 Exec. Order No. 12866 (September 30, 1992) (requiring federal agencies to analyze the costs and benefits of the
proposed regulatory action to determine whether there is a compelling public need for the action).
60 78 Fed. Reg. 39307 (July 1, 2013).
61 40 C.F.R. §1508.4 (“Categorical exclusion means a category of actions which do not individually or cumulatively
have a significant effect on the human environment.... ”)
62 17 Fed. Reg. 7371 (August 13, 1952) (following a 15-day comment period).
63 77 Fed. Reg. 3330 (January 23, 2012). The listing also specified two subspecies of Python molurus, which are
counted separately.
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Criteria for Finding Injurious Species
While FWS has not employed notice and comment rulemaking procedures to adopt a regulatory
definition of injurious species, or regulatory criteria for what factors must be evaluated to make
that regulatory finding, FWS has developed informal guidance to direct its injurious species
determinations. Species may be considered for the black list either by petition to FWS or by FWS
under its own authority.64 Based on the statute, FWS must find that a species is injurious to
“agriculture, horticulture, forestry, or to wildlife or the wildlife resources of the United States.”65
When evaluating whether a species is injurious, FWS may publish a notice in the Federal
Register soliciting information.66
According to a guidance document provided by FWS to CRS,67 FWS conducts a risk analysis to
assess the likelihood of escape, establishment, and eradication of a proposed injurious species. It
also considers the likelihood and magnitude of the injurious species’ impact on species listed
under the Endangered Species Act; humans; agriculture; horticulture; and forestry.68 Economic
and environmental impacts are considered.69
H.R. 996/S. 1153 would establish a more formal petition process and allow any person to petition
to list a species.70 The bills would require petitions for listing species to include “adequate
information” for the FWS to make its injurious species determination.71 This is similar to the
requirement in the Endangered Species Act (ESA) that FWS determine whether a petition to list a
species under that act presents substantial scientific information for the FWS to make a listing
determination.72
Shared Listing Authority
The shared listing responsibility between the FWS and Congress has had mixed results, with both
redundant listings and unintentional delistings occurring, as discussed below.73 In theory,
Congress should be able to act faster than FWS to list a species because Congress does not have a
formal APA process to follow. Thus, Congress could potentially use the legislative process to bar
species before they became established. FWS, on the other hand, arguably is in a better position
to evaluate the harm a species would cause, as it is required by the Lacey Act to make an
injurious finding with respect to the species under consideration. While the shared listing

64 See generally, FWS Injurious Species listing process, http://www.fws.gov/injuriouswildlife/pdf_files/
InjuriousWildlifeEvaluationProcessFlowChart.pdf.
65 18 U.S.C. §42(a)(1). The original Lacey Act injurious species provision authorized the Secretary of Agriculture to
designate species as “injurious to the interest of agriculture or horticulture.” 31 Stat. 188, §2.
66 See, e.g., Review of Information Concerning Constrictor Snakes From Python, Boa, and Eunectes genera, 73 Fed.
Reg. 5784 (January 31, 2008); Review of Information Concerning Brush-Tailed Possums of the Genus Trichosurus, 61
Fed. Reg. 1893 (January 24, 1996).
67 See Appendix A for a copy of the FWS criteria for listing information.
68 Id.
69 Id.
70 H.R. 996/S. 1153.
71 H.R. 996, §4(b); S. 1153, §4(b).
72 16 U.S.C. §1533(b)(3)(A).
73 See “Taxonomic Consistency.”
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responsibility appears to strike a balance between speed and science in barring injurious species,
in practice, the efforts are not always coordinated. The brown tree snake, for example, was listed
by regulation and statute. FWS completed the regulatory process for adding the snake in April
1990,74 and Congress listed it in December 1991.75
The bigger controversy is whether the speed by which the FWS identifies and bans injurious
species is adequate. The act’s premise is that injurious species will harm U.S. agricultural and/or
wildlife interests if allowed into the country. Presumably, a lengthy process to ban injurious
species would expose domestic plants and animals to harm. Quick, or preferably pre-emptive,
bans on harmful species could limit damage. In H.R. 996/S. 1153, Congress is considering
requiring FWS to make regulatory listings within 180 days.
Prior to passage of NEPA, regulatory listings took only a few months. For example, the regulation
that added salmon, dioch, pink starling, Java sparrow, and the red-whiskered bul-bul, was
proposed for listing on July 27, 1967, and a final notice was issued on December 21, 1967.76 The
walking catfish was proposed for listing on August 19, 1969, and a final notice was published on
November 29, 1969.77 After NEPA was enacted on January 1, 1970, the first subsequent listing
took over six months from the proposed notice,78 and over a year from when FWS published a
notice that it intended to review the species.79
Species added in the last decade have taken
Asian Carp80
more time to list, on average. For example, a
According to the USGS, during the 1970s, bighead and
petition to list certain invasive carp species
silver carp were imported into the United States for use
was received by FWS in October 2002.81 The
in aquaculture production of food fish and biological
final listing decision was issued five years
control of plankton in aquaculture ponds and sewage
treatment lagoons. Within 10 years, the carp escaped
later, with two other carp species included.82
confinement and spread to the waters of the Mississippi
Also in 2002, however, FWS listed snakehead
River basin and other large rivers. Today, the carp live in
fish in just three months, specifically
23 states; their population numbers are increasing
identifying 28 of the 34 known species, which
exponentially, and, in addition, they are close to entering
suggests that the administrative process was
the Great Lakes.
not the obstacle in listing carp.83
The carp are in direct competition with native aquatic
species for food and habitat. Their rapid population
While the act is intended to ban species to
increase is disrupting the ecology and food web of the
large rivers of the Midwest, including the Missouri River.
protect domestic plants and animals, banning a
species may have negative economic effects

74 55 Fed. Reg. 17441 (April 25, 1990) (to take effect May 25, 1990).
75 105 Stat. 1901 (December 31, 1991).
76 32 Fed. Reg. 20656 (December 21, 1967).
77 34 Fed. Reg. 19030 (November 29, 1969).
78 47 Fed. Reg. 21892 (May 20, 1982) (proposed); 47 Fed. Reg. 56362 (December 16, 1982) (final).
79 46 F.R. 58348 (December 1, 1981).
80 This text is a quotation from the USGS Columbia Environmental Research Center: Invasive Carp Research Program,
http://www.cerc.usgs.gov/Branches.aspx?BranchId=40. For details on Asian carp, see CRS Report R41082, Asian
Carp and the Great Lakes Region.
81 See 72 Fed. Reg. 37459 (July 10, 2007).
82 72 Fed. Reg. 59019 (October 18, 2007).
83 67 F.R. 48855 (July 26, 2002) (proposed); 67 Fed. Reg. 62193, 62203 (October 4, 2002) (final). Congress added a
fourth species of carp to the injurious species list in 2010. 124 Stat. 3282 (2010) (bighead carp). See Appendix A.
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on those who find the animal useful.84 That conflict may influence the length of the listing
process. Just as carp has a beneficial use for catfish farmers, pythons were favored by the pet
trade and pet owners. Both the carp and the constrictor snake petitions took years, and Congress
considered legislative bans while those rulemakings were pending. For example, the petition to
ban importing the Burmese python was received in June 2006.85 The final rule was issued in
2012.86 During that six years, Congress introduced legislation to ban constrictor snakes, S. 373
and H.R. 2811 (111th Congress), but neither bill was voted on by its respective house. Similarly,
while the carp regulatory ban was pending, Congress did not vote on S. 1402 or H.R. 3049 (109th
Congress), which could have added four carp species to the black list in 2005, seven years before
the regulation took effect.87
H.R. 996/S. 1153 would establish deadlines for listing, requiring the agency to publish a final
determination within 180 days of publishing the proposed listing notice.88 The bill does not
reference NEPA.

Burmese Python
The Burmese python, and possibly other large constrictor snakes, are invasives in south Florida. According to the
National Park Service (NPS), from 2000 to 2012, 1,950 Burmese pythons were removed from the Everglades
National Park and environs. “Exotic snakes found in the park are often the result of accidental and intentional release
by pet owners. These introductions can have devastating consequences to [the] ecosystem.”89
Introduction of any type of plant or animal into a national park is illegal under 36 C.F.R. Section 2.1.90 Even though the
regulation was promulgated in 1983, it has not stopped the introduction or expansion of pythons in the park.91
Scientists found the first python nests in 2006, although pythons were present in the park at least since the 1990s.92
According to the National Park Service, “Florida now ranks as having the largest number of established non-
indigenous reptile species in the entire world.... ”93
According to a study published by the National Academy of Sciences, the Burmese python is linked to a severe
decline in the mammal populations of the Everglades National Park.94 For example, night drives through the park
revealed a greater than 98% decrease in raccoons, and no rabbits.95

84 See, e.g., Greenwire, “Snake owners seething about new restrictions” (January 10, 2011) http://www.eenews.net/
greenwire/stories/1059943838/search?keyword=python (“The ban is infuriating snake owners and breeders as well as
zoologists and some conservationists, all of whom could stand to lose financially”).
85 See 73 Fed. Reg. 5784 (January 31, 2008).
86 77 Fed. Reg. 3330 (January 23, 2012).
87 77 Fed. Reg. 3330 (January 23, 2012).
88 H.R. 996, §4(d); S. 1153, §4(d).
89 NPS, Everglades National Park, Burmese Pythons, http://www.nps.gov/ever/naturescience/burmesepythonsintro.htm.
90 36 C.F.R. §2.1(a)(2)“Except as otherwise provided in this chapter, the following is prohibited.... Introducing wildlife,
fish or plants, including their reproductive bodies, into a park area ecosystem.”
91 48 Fed. Reg. 30282 (June 30, 1983).
92 NPS, Everglades National Park News Release, Frequently Asked Questions about Burmese Pythons (January 11,
2013), p. 2, http://www.nps.gov/ever/parknews/loader.cfm?csModule=security/getfile&pageid=466932.
93 NPS, Everglades National Park News Release, Frequently Asked Questions about Burmese Pythons (January 11,
2013), p. 1, http://www.nps.gov/ever/parknews/loader.cfm?csModule=security/getfile&pageid=466932.
94 Michael E. Dorcas, et al., Severe Mammal Declines Coincide with Proliferation of Invasive Burmese Pythons in
Everglades National Park, Proceedings of the National Academy of Sciences (December 2011), http://www.pnas.org/
content/109/7/2418.full.
95 Id.
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Legal Issues Before Congress
As Congress evaluates bills to overhaul the regulatory process and add new injurious species,
several issues may arise. One issue is the taxonomic consistency of the injurious species list and
whether only certain classifications should be used. Other issues are whether listing the quagga
mussel would unduly burden interstate water deliveries to the extent that the mussels are
transported with the water, or whether the law is an effective tool in preventing unintentional
imports or shipments of species.
Did Congress Ban Transport as Well as Shipment?
The injurious species provision clearly bans import and shipment.96 However, virtually every
publication by FWS on injurious species indicates that import and transport are barred.97 FWS
has no rulemaking harmonizing its interpretation with the statute. No court has considered the
issue. This leaves open the question as to whether the FWS interpretation is consistent with
congressional intent.
Under the U.S. Supreme Court ruling in Chevron v. Natural Resources Defense Council,98 a
reviewing court must provide deference to an agency’s interpretation of an ambiguous statutory
provision. First, the court must determine whether the statute is ambiguous. If the court
determines that the statutory text is clear, the agency and the court must give effect to Congress’s
expressed intent.99 However, if the court determines that the statute is ambiguous, the court must
accept the agency’s interpretation if it is a permissible construction of the statute.100 Therefore, if
a court finds that 18 U.S.C. Section 42 is clear and bans only import and shipment as stated, the
FWS’s interpretation to include transport would be rejected. However, if the reviewing court
determines the language was ambiguous, then it would uphold FWS’s interpretation that the law
also bans transport of listed species, if the court determines that the interpretation was reasonable.
The issue of whether the injurious species provision pertains to transport as well as shipment
primarily arises in the case of zebra mussels, although the interstate movement of carp
unintentionally included in catfish transports also may be at stake.101 If the law applies to
transport and not just shipment, more actions would be covered.

96 18 U.S.C. §42(a)(1). The words shipment and transport have distinct meanings. Definition Ship: To send (goods,
documents, etc.) from one place to another, esp. by delivery to a carrier for transportation. Definition Transport: To
carry or convey (a thing) from one place to another. Bryan A. Garner, ed., Black’s Law Dictionary (8th ed. 2004).
97 See, e.g., FWS, Fish and Aquatic Conservation: Injurious Species, http://www.fws.gov/injuriouswildlife/ (“Under the
Lacey Act (18 U.S.C. 42), the Secretary of the Interior is authorized to regulate the importation and transport of species
...”).
98 467 U.S. 837 (1984).
99 Id.
100 Id.
101 To the extent that species are banned under state law, the trade provision of the Lacey Act may restrict their
transport, if part of interstate commerce. 16 U.S.C. § 3372(a)(2).
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It could be interpreted that the statute’s ban on
Lake Texoma106
shipment of injurious species does not
constitute a broader ban on transporting or
In 1989, the Corps of Engineers granted an easement and
permit to the North Texas Municipal Water District to
carrying injurious species. Congress limited
construct and operate an intake/pumping station at Lake
the injurious species provision to shipment,
Texoma. The pump station was designed to transfer up
whereas in other parts of the full Lacey Act, it
to 125 million gallons per day of water from Lake
used different terms. For example, in 18
Texoma directly to Lake Lavon via a pipeline that
U.S.C. Section 42(c), which is part of the
discharges into a tributary of Lake Lavon. The massive
intake structure cost over $100 mil ion to construct.
Lacey Act, but not the injurious species
provision, Congress addresses the conditions
As a result of boundary renegotiations that took effect in
August 2000, a portion of the North Texas Municipal
for transportation of species to the United
Water District intake facility is now located in the state
States and does not reference shipment.102 A
of Oklahoma. Zebra mussels have been identified as
second example is found in the trade
being in Lake Texoma since 2009. This has raised
provision, which at the time of the 1960
concerns that this invasive species could be transferred
amendments adding shipment to 18 U.S.C.
across state lines to Texas via the water transfer. Lake
Texoma comprises 28% of the total water supply needs
Section 42(a), was still codified with the
for North Texas residents or enough water for 500,000
injurious species provision (as 18 U.S.C. §43).
people.
After prohibiting only import and shipment in
In December 2010, FWS advised the water district that
the injurious species provision of Section 42,
because of the revised boundary delineation, the use of
Congress prohibited in former Section 43
the pump station would constitute an interstate transfer
three distinct actions related to wildlife trade:
of water and a violation of the Lacey Act because
carry, transport, or ship.103 That language was
invasive zebra mussels would be transported across state
amended in 1981 to apply to import, export,
lines.
and transport.104 Under general rules of
In December 2012, Congress exempted the water
statutory construction, “where Congress
transfer from the Lacey Act in P.L. 112-237, Section 5.
includes particular language in one section of
a statute but omits it in another ... it is generally presumed that Congress acts intentionally and
purposely in the disparate inclusion or exclusion.”105 This suggests that it may be meaningful that
with regard to injurious species, only the acts of import and shipment are prohibited, while under
the trade provision, the acts of carry and transport are prohibited.
Under a separate canon of statutory construction, it is fair to interpret shipment as meaning the act
of shipping, rather than as a synonym for transport: As the Supreme Court has stated: “A term
appearing in several places in a statutory text is generally read the same way each time it
appears.”107 Therefore, shipment in 18 U.S.C. Section 42(a) would not mean both shipment and
transport, because those are identified as separate prohibited acts in 18 U.S.C. Section 42(c) and
former Section 43 (now 16 U.S.C. §3372). It could be argued that if Congress had meant for the
injurious species provision to apply to shipping and transport, it would have included the term
transport explicitly in the text, as it did in the other two times it is used.

102 74 Stat. 754. See footnote 13 for more on 18 U.S.C. §42(c).
103 Id.
104 95 Stat. 1074; 16 U.S.C. §3372. Transport is defined by the trade provision as “move, convey, carry, or ship by any
means, or deliver or receive for the purpose of movement, conveyance, carriage, or shipment.” 16 U.S.C. §3371(k).
105 Keene Corp. v. United States, 508 U.S. 200, 208 (1993) (quoting Russello v. United States, 464 U.S.16, 23 (1983)).
106 This summary is taken from H.Rept. 112-657.
107 Ratzlaf v. United States, 510 U.S. 135, 143 (1994).
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There appears, however, to be no discussion in the legislative history of why shipment was added
to the injurious species provision (Section 42) in 1960. When discussing Section 42, the Senate
report108 refers only to import, and similarly, refers to transportation only when referring to trade.
According to the Senate report, the change in the trade provision was made to recognize that
wildlife taken in violation of other laws was shipped not only by rail and water, but also by air
and truck.109 Accordingly, there is no indication in the legislative history that using the word
shipment in Section 42 was intended to expand the definition of prohibited activities to any form
of transport.
It is also worth noting that the 1960 amendment changed the parties responsible for costs of
returning or destroying the banned species from “importer” to “importer or consignee.”110 The
term consignee appears to suggest commercial shipping, and not the more general term,
transporting. The current language of the injurious species provision still refers only to an
importer or consignee, and does not refer to a transporter.111
If the injurious species provision were narrowly interpreted, it appears possible that the FWS
would enforce the law differently. Under such interpretation, a reviewing court may find that
incidental transport of species across state lines did not violate the law because only the
commercial act of shipping would violate the act. Intentionally imported and commercially traded
pythons would still violate the law. Imports including species that have not established
themselves in the United States, such as fruit bats and meerkats, would still be stopped at ports.
However, the incidental and probably unintentional transport of zebra mussels, via water systems,
appears not to violate the injurious species provision. It is not clear whether restricted
enforcement would impact the spread of already established injurious species such as the zebra
mussel, Asian carp, or Burmese pythons, however.
A narrow interpretation of the injurious species provision, however, would not preclude other
federal action to address injurious species that are unintentionally transported via water, as the
Nonindigenous Aquatic Nuisance Prevention and Control Act (NANPCA) appears to apply to
such situations. In NANPCA, Congress acknowledged that zebra mussels are not intentionally
imported or shipped. NANPCA states: “The zebra mussel was unintentionally introduced into the
Great Lakes”;112 and “aquatic nuisance species are unintentionally transported and introduced into
inland lakes and rivers by recreational boaters, commercial barge traffic, and a variety of other
pathways.”113 It authorizes the Coast Guard to issue regulations regarding their control.114
It could be argued that Congress devised a two-part system for aquatic invasive species: where
those species were intentionally imported or shipped, FWS and Customs would block their import
under the injurious species provision of the Lacey Act; where those species were unintentionally
imported or transported, the Coast Guard would have authority under NANPCA. This may

108 S. Rept. 1883 (86th Congress) Importation of Injurious Mammals, Etc., Committee on the Judiciary (August 22,
1960).
109 S. Rept. 1883 (86th Congress), p. 2.
110 74 Stat. 754.
111 18 U.S.C. §42(a)(1)
112 NANPCA §1002(a)(3); 16 U.S.C. §4701(a)(3).
113 NANPCA §1002(a)(14); 16 U.S.C. §4701(a)(14).
114 16 U.S.C. §4701(b), referencing Secretary, which is defined in 16 U.S.C. §4702(12) as “the Secretary of the
department in which the Coast Guard is operating.”
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suggest that injurious species conveyed unintentionally through water transfers were not intended
to be within the FWS injurious species authority.
Limits on Law’s Effectiveness
The injurious species provision bans the intentional import of injurious species of animals (such
as fruit bats to California). The law appears designed to prevent injurious species from being
introduced into the United States and provides for their destruction when discovered. The act,
however, appears to have had a limited impact on species that have already become established in
the United States, such as the English sparrow, the zebra mussel, or the Burmese python likely
because it does not authorize eradication or other control of species in the wild.
It is difficult to assess enforcement of the act. CRS has not found any published court decisions
regarding prosecutions under the act. FWS has provided nine examples of recent enforcement.115
There is no indication from these examples whether the defendants contested either the charges or
the fines.
The injurious species provision is silent as to the extent a defendant’s knowledge of the action
must be shown to prove a violation. Prosecuting unintentional violations, that is, imposing strict
liability, raises enforcement challenges. The question of intentional violations parallels the
analysis of shipping versus transporting to some extent. Shipping can be seen as an intentional
act, whereas transporting may be accidental. While commercial interstate shipping, for example,
of listed pythons, would leave records that could lead to enforcement action (such as bills of
lading, receipts, etc.), other transport appears extremely difficult to monitor. While recreational
boaters who incidentally transport mussels when towing their boats would present evidence of the
crime on the boats’ hulls, the intent to commit an offense is less easy to demonstrate. The
difficulty in restricting interstate shipments or transport is compounded by the fact that the two
enforcement agencies, FWS and Customs, maintain permanent enforcement presences only at
designated international airports.116 Restricting the act to knowing violations, and/or to shipping,
may be seen as matching the enforcement abilities of the agencies with the language of the
statute.
It could be argued that the easiest way to make the law work is to focus on banning the
intentional import of species prior to their presence in the country. That would allow enforcement
at the port of entry. It would not assist in removing established invasives or help block unintended
imports.
Different legislation would be needed for those species that do not fit the narrow reach of the
injurious species provision. But even as more state laws address ballast water contamination to
fend off zebra and quagga mussels and other aquatic nuisances, preventing the spread seems
futile without a large enforcement presence. As illustrated by the case of Asian carp, whose
import was intentional, even if their release was not, enforcement is slippery. A member of the
U.S. Geological Survey has stated: “Even if 95 percent of people hate the carp with a passion, it

115 Five examples available online at U.S. Fish and Wildlife, Office of Law Enforcement, http://www.fws.gov/le/pdf/
FWSOLEInvasiveSpeciesEnforcement.pdf. Other examples are available from the author as transmitted via e-mail
from Kevin Garlick, Special Agent in Charge, Investigations, U.S. FWS, to the author (July 10, 2013). The dates of the
actions were not available.
116 See FWS Law Enforcement, Designated Ports, http://www.fws.gov/le/designated-ports.html.
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just takes one percent of people, or even one person, to move them around. We don't want people
to do so and it is illegal to do so. But it is awfully hard to catch someone doing that.”117
Creature Limits
While the Lacey Act applies to many animal species, it does not apply to them all (notably, it does
not apply to insects, microbial parasites, or disease vectors).118 The Department of Agriculture,
Animal and Plant Health Inspection Service (APHIS) is responsible for protecting plant and
animal resources from domestic and foreign agricultural pests and diseases.119
The Lacey Act injurious species provision appears to apply only to live animals, their offspring
and eggs, referring only to dead animals with respect to an exception for museums or scientific
collections.120 FWS, however, has used its injurious species regulatory authority to stop the
import of dead salmon species unless there is proof that the fish are virus-free.121
As the only example of FWS barring import of a dead species under the injurious species
provision, it is worth noting that FWS is using the ban as a tool, not to prevent salmon imports,
which are not invasive when dead, but to bar diseases they can carry.
It is also worth noting that Congress is free to add via statute any species it wants, including
plants. Accordingly, it could add insects or bacteria to the black list. However, there is a question
whether the injurious species provision bans function effectively as to species that are not
intentional imports. See “Limits on Law’s Effectiveness,” above.
Taxonomic Consistency
Another difficulty in interpreting the black list is the variations of language used to describe the
listed animals. Common names are used and sometimes scientific names as well. Also, while the
statute strongly indicates that only species are to be listed, both Congress and FWS have listed
animals at other taxonomic levels. For example, in the case of the mongoose, the statutory ban is
on “the mongoose of the species Herpestes auropunctatus,” which would ban one species, but the
regulation bans “any species of mongoose or meerkat of the genera Atilax, Cynictis, Helogale,
Herpestes, Ichneumia, Mungos, and Suricata,” which would block 19 species from import.122
Similarly, the zebra mussel ban reads “Live mollusks, veligers [juveniles], or viable eggs of zebra
mussels, genus Dreissena.” While there are two species in genus Dreissena,123 only the zebra
mussel is banned under FWS regulations.124 The listing of python includes redundant common

117 USGS, CERC News: The Crusade Against Asian Carp—Where Does It Go Now? (February 28, 2012) (quoting
Duane Chapman, Asian carp expert, U.S Geological Survey), online at http://www.cerc.usgs.gov/NewsItems.aspx?
NewsItemId=163.
118 Examples of animal parasites and disease vectors can be found on the injurious species black list. For example,
some bats are considered parasites, and salmon were banned because they were vectors.
119 USDA, About APHIS, http://www.aphis.usda.gov/about_aphis/.
120 18 U.S.C. §42(a)(4).
121 50 C.F.R. §16.13(a)(3).
122 50 C.F.R. §16.11(a).
123 See Interagency Taxonomic Information System (ITIS) database, online at http://www.itis.gov.
124 50 C.F.R. §16.13(a)(2)(iii).
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names and identifies two subspecies, but not all subspecies, suggesting some are not covered.125
The family Salmonidae includes hundreds of species. Accordingly, a precise number of species
on the black list is unavailable.
Redundancy in listing is less of a problem than omission, but there are examples of where
regulation may have unintentionally delisted a species. At one point, in the 1950s, both the
European rabbit (Lepus cuniculus) and the European hare (Lepus europaeus) were listed species.
By regulation, FWS switched to the genus (Oryctolagus), but the scientific name of the European
hare did not change, and it is not now of the genus.126 It is unclear if FWS planned to delist the
species. Similarly, both mynahs and starlings were black-listed by regulation in 1952, which
listed them by genera: “Acridotheres and Sturnus.”127 A notice described as a clarification was
published in 1954, indicating only Acridotheres was black-listed.128 When Congress removed
starlings, Sturnus, from the list in 1960,129 Acridotheres also dropped off the regulatory list.130

125 50 C.F.R. §§16.15(a)(3)-(4).
126 See ITIS database, http://www.itis.gov.
127 17 Fed. Reg. 7371 (August 13, 1952).
128 19 Fed. Reg. 3687 (June 25, 1954).
129 74 Stat. 753. H. Rept. 86-1953, at 2 (August 22, 1960) (“Reference to the starling and the English sparrow would be
eliminated from the section by our suggested review.”).
130 The last reference found in Federal Register to Acridotheres on the injurious species list is September 1, 1960, the
day before the 1960 amendments to the injurious species provision were enacted. 25 Fed. Reg. 8407 (September 1,
1960).
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Appendix A. Injurious Species
Table of Black-Listed Species

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Source: Prepared by FWS. Available at http://www.fws.gov/injuriouswildlife/pdf_files/
Current_Listed_IW.pdf.
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Appendix B. FWS Criteria for Making an Injurious
Species Determination
The following document is produced by FWS.
Source: U.S. Fish and Wildlife Service, via e-mail from Craig Johnson, Chief, FWS Branch of
Aquatic Invasive Species to the author (June 26, 2013).

BASIS FOR DETERMINATION Please provide a written justification/summary for
the criteria listed below. Several criteria will receive a High/Low ranking. A separate
ranking spreadsheet is attached. If the criteria does not apply to the species being
evaluated, please indicate by writing not applicable.

Factors that contribute to injuriousness
A.
Likelihood and magnitude of release or escape, including pathway(s):
B.
Likelihood and magnitude of survival and establishment (with or without
reproduction) if released or escaped, including “acceptable” thresholds):
C.
Likelihood and magnitude of spread:
D.
Likelihood and magnitude of adverse impacts on native wildlife, wildlife
resources, ecosystem balance, including what native species other than ESA listed
species are or are likely to be affected?
a.
Potential for hybridizing or inter-breeding
b.
Competition for food and habitats
c.
Potential to cause habitat degradation and/or destruction
d.
Predation of native wildlife
e.
Potential to transfer pathogens
f.
Additional adverse impacts on native wildlife, wildlife resources, and
ecosystem balance.
E.
Likelihood and magnitude of effect on:
a.
Threatened and Endangered species. Please provide number of species.
b.
Designated critical habitats of Threatened or Endangered species
c.
Candidate species
F.
Likelihood that one or more species may be placed in danger of extinction or
endangered within the foreseeable future as a result of introduction/establishment:
G.
Likelihood and magnitude of ancillary wildlife resource damages due to control
measures (including, but not limited to, damage from equipment/chemicals used,
increased risk of reinvasion due to ineffective treatment, or disturbance caused by
removal):
H.
Likelihood and magnitude of impact on (high/low ranking not required):
a.
Human beings
b.
Agriculture
c.
Horticulture
d.
Forestry
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

I.
Additional considerations that contribute or are likely to contribute to
injuriousness:

Measures that reduce or remove injuriousness
J.
Ability and effectiveness to: (high responses indicate a low risk)
a.
Prevent escape and establishment, including crisis management/rapid
response
b.
Eradicate
c.
Manage established populations
d.
Control spread to new locations
e.
Prevent and control the spread of pathogens
f.
Rehabilitate and recover ecosystems disturbed by the species
K.
Potential ecological benefits for introduction: (high/low ranking not required)

Are there additional measures (i.e., triploidy, sterility) that reduce or remove or are likely to
reduce or remove injuriousness? (high/low ranking not required)
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Injurious Species Listings Under the Lacey Act: A Legal Briefing

Author Contact Information

Kristina Alexander

Legislative Attorney
kalexander@crs.loc.gov, 7-8597

Acknowledgments
The author would like to thank Dr. M. Lynne Corn, CRS Specialist in Natural Resources Policy, for her
extensive help with species identification and consistency. Also, credit for the graphic chart is to Amber
Wilhelm, CRS Graphics Specialist.

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