[Federal Register: July 10, 2007 (Volume 72, Number 131)]
[Rules and Regulations]               
[Page 37459-37469]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 16

RIN 1018-AT29

Injurious Wildlife Species; Silver Carp (Hypophthalmichthys 
molitrix) and Largescale Silver Carp (Hypophthalmichthys harmandi)

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.


SUMMARY: The U.S. Fish and Wildlife Service (Service or we) adds all 
forms of live silver carp (Hypophthalmichthys molitrix), gametes, 
viable eggs, and hybrids; and all forms of live largescale silver carp 
(Hypophthalmichthys harmandi), gametes, viable eggs, and hybrids to the 
list of injurious fish, mollusks, and crustaceans under the Lacey Act. 
The best available information indicates that this action is necessary 
to protect the interests of human beings, and wildlife and wildlife 
resources, from the purposeful or accidental introduction, and 
subsequent establishment, of silver carp and largescale silver carp 
populations in ecosystems of the United States. Live silver carp and 
largescale silver carp, gametes, viable eggs, and hybrids can be

[[Page 37460]]

imported only by permit for scientific, medical, educational, or 
zoological purposes, or without a permit by Federal agencies solely for 
their own use; permits will also be required for the interstate 
transportation of live silver or largescale silver carp, gametes, 
viable eggs, or hybrids currently within the United States. Interstate 
transportation permits may be issued for scientific, medical, 
educational, or zoological purposes.

DATES: This rule is effective August 9, 2007.

FOR FURTHER INFORMATION CONTACT: Kari Duncan, Chief, Branch of Invasive 
Species at (703) 358-2464 or kari_duncan@fws.gov.



    In October 2002, the U.S. Fish and Wildlife Service (Service or we) 
received a petition signed by 25 members of Congress representing the 
Great Lakes region to add silver, bighead, and black carp to the list 
of injurious wildlife under the Lacey Act (18 U.S.C. 42). A follow-up 
letter to the original petition had seven additional Legislator 
signatures that supported the petition.

Summary of Previous Actions

    The Service published a Federal Register notice of inquiry on 
silver carp (68 FR 43482-43483, July 23, 2003), and provided a 60-day 
public comment period. We received 31 comments in total, but 12 of 
these did not address the issues raised in the notice of inquiry. We 
considered the information provided in the 19 relevant comments.
    Most of the comments supported the addition of silver carp to the 
list of injurious wildlife, but provided no additional information. One 
commenter noted that silver carp have no commercial value, but was 
concerned that listing would hinder control and management. One 
commenter asked us to delay listing until a risk assessment could be 
completed. Biological synopses and risk assessments were completed for 
silver and largescale silver carp. A proposed rule to add all forms of 
live silver and largescale silver carp to the list of injurious fishes 
under the Lacey Act was published on September 5, 2006 (71 FR 52305); 
the comment period on the proposed rule closed on November 6, 2006. We 
received 97 comments on the proposed rule. In total, the Service 
received 116 pertinent letters during the public comment periods. Most 
of the 116 letters received urged the Service to list silver and 
largescale silver carp as injurious wildlife, but provided no 
additional information. Similar comments were grouped into issues; 
these issues and our responses to each are presented below.

Comments Received on the Proposed Rule

    Issue: One commenter stated that there is currently no market for 
silver carp; very few silver carp are in culture (for maintenance of 
stocks) or use. However, there is great potential for silver carp use 
in aquaculture within Arkansas and Mississippi by utilizing an enclosed 
system that would prevent escape of silver carp. The potential for 
silver carp use in the United States has not been fully realized.
    Response: This rule will prohibit the importation and interstate 
transport of live silver carp, gametes, viable eggs, and hybrids, which 
will in no way affect the use of silver carp in States where they 
already exist.
    Issue: One aquaculture industry group stated that there is no 
meaningful role of silver carp in cleaning ponds and tanks for southern 
U.S. aquaculture producers and that there would be little or no 
economic impact associated with this rule. However, they also noted 
that the natural invasion of silver carp will continue into waters of 
other States, whether the proposed rule is enacted or not. The comment 
stated that, given the existing conditions and circumstances of silver 
carp, listing these species will do little or nothing to address the 
problems stated in the proposed rule. Listing would not address the 
real problem of preventing the spread of naturally occurring 
populations; States already have the authority to address these 
problems, so Federal intervention does not seem necessary.
    Response: The Service agrees that this rulemaking will not address 
the ecological impacts of silver carp already in the environment. This 
rulemaking is intended to prevent or delay the introduction of silver 
carp into waterbodies where they do not currently exist, which will 
help protect native species. Many States have requested Federal 
intervention because the States only have authority to regulate 
possession within State boundaries.
    Issue: A few commenters stated that they did not understand why 
nine questions were included in the proposed rule. These commenters 
believe that asking those questions has delayed the rulemaking. In 
addition, they expressed concern with the length of time it takes to 
add species to the list of injurious wildlife.
    Response: Nine questions were included in the proposed rule in 
order to ascertain if there were any additional data pertinent to the 
analyses required by various laws and executive orders relating to the 
Federal rulemaking process. Inclusion of these nine questions has in no 
way delayed the process of adding silver and largescale silver carp to 
the list of injurious wildlife.
    Issue: One commenter stated that the proposed rule contained 
repetition of unnecessary facts and that many assumptions were made 
without scientific research.
    Response: The Service has reviewed the proposed rule to reduce 
repetition in the final rule. Research has been conducted on silver 
carp impacts and due to the similarities between silver carp and 
largescale silver carp, we feel that reasonable extrapolations of 
potential impacts have been made.
    Issue: A few commenters stated that penalties for injurious 
wildlife should be increased.
    Response: Penalties for violations of the Lacey Act are set by 

Peer Review

    We asked scientists who have knowledge of fisheries biology or 
invasive species to provide peer review of the proposed rule during the 
public comment period. The peer reviewers had a few technical comments 
and suggestions; however, all concluded that the data and analyses used 
in the proposed rule were appropriate and the conclusions drawn were 
clear and concise. Additionally, peer reviewers provided additional 
documentation of potential impacts to native species. This information 
has been incorporated into the final rule.

Description of the Final Rule

    The regulations contained in 50 CFR part 16 implement the Lacey Act 
(18 U.S.C. 42) as amended. Under the terms of the injurious wildlife 
provisions of the Lacey Act, the Secretary of the Interior is 
authorized to prohibit the importation and interstate transportation of 
species designated by the Secretary as injurious. Injurious wildlife 
are those species, offspring, and eggs that are injurious to wildlife 
or wildlife resources, to human beings, or to the interests of 
forestry, horticulture, or agriculture of the United States. Wild 
mammals, wild birds, fish, mollusks, crustaceans, amphibians, and 
reptiles are the only organisms that can be added to the injurious 
wildlife list. The lists of injurious wildlife are at 50 CFR 16.11-
    By adding all forms of live silver carp and largescale silver carp, 
including hybrids, to the list of injurious wildlife,

[[Page 37461]]

their importation into, or transportation between, States, the District 
of Columbia, the Commonwealth of Puerto Rico, or any territory or 
possession of the United States by any means whatsoever is prohibited, 
except by permit for zoological, educational, medical, or scientific 
purposes (in accordance with permit regulations at 50 CFR 16.22), or by 
Federal agencies without a permit solely for their own use. Federal 
agencies who wish to import silver carp or largescale silver carp for 
their own use must file a written declaration with the District 
Director of Customs and the U.S. Fish and Wildlife Service Inspector at 
the port of entry. No live silver carp or largescale silver carp, 
progeny thereof, viable eggs, or hybrids imported or transported under 
permit may be sold, donated, traded, loaned, or transferred to any 
other person or institution unless such person or institution has a 
permit issued by the U.S. Fish and Wildlife Service. The interstate 
transportation of any live silver carp or largescale silver carp, 
gametes, viable eggs, or hybrids currently held in the United States 
for any purpose is prohibited without a permit. Any regulation 
pertaining to the possession or use of silver carp and largescale 
silver carp within States continues to be the responsibility of each 


    The commonly named silver carp belongs to the family Cyprinidae, 
with the species name of Hypophthalmichthys molitrix. Silver carp are 
native to Asia (China and Eastern Siberia), from about 54 [deg]N 
southward to 21 [deg]N. Silver carp are primarily phytoplanktivores, 
but are highly opportunistic, eating phytoplankton, zooplankton, 
bacteria, and detritus. Silver carp are well established throughout 
much of the Mississippi River Basin, and its range is expanding in that 
    The commonly named largescale silver carp (or southern silver carp 
or Vietnamese carp) also belongs to the family Cyprinidae, with the 
species name of Hypophthalmichthys harmandi. Largescale silver carp are 
native to fresh waters of northern Hainan Island, China, and the Red 
(Hong Ha) River of northern Vietnam from subtropical to tropical (21-22 
[deg]N). The species does not occur naturally on the Chinese mainland. 
Largescale silver carp feed on phytoplankton and prefer slow-moving, 
plankton-rich open waters. There is no indication that this species has 
been imported into or introduced into the open waters of United States.
    For additional information on the biology, use, history and 
pathways of introduction into the United States for silver and 
largescale silver carp, please refer to the proposed rule published in 
the Federal Register on September 5, 2006 (71 FR 52305).

Factors That Contribute to Injuriousness for Silver Carp

Introduction and Spread

    The major pathway for introduction of silver carp in the United 
States was importation for biological control of plankton in 
aquaculture ponds and sewage lagoons. The pathway that led to the 
presence of this species in open waters of the United States was likely 
escape from these facilities. Subsequent escapes and the mixture of 
silver carp with other species that were stocked likely contributed to 
the expansion of the species' range, along with natural reproduction.
    Other probable pathways that may aid the spread of existing 
populations of silver carp include connected waterways, contamination 
of pond-grown baitfishes with silver carp, ballast water release, 
release or escape from livehaulers that support commercial fisheries, 
or spread by commercial fishers themselves.
    Silver carp are difficult to handle and transport because of their 
propensity to jump when disturbed. As a result, there has been very 
little culture of silver carp in the United States since 1985, and they 
are not being cultured commercially at this time. However, should 
culture of silver carp resume, a potential pathway for introduction 
would be escape or release from a facility or during the transport and 
sale of live fish in retail markets.
    Silver carp are likely to be spread when juveniles are collected by 
cast net for use as live baitfish. Silver carp juveniles are very 
similar in appearance to shad, and anglers sometimes catch young silver 
carp and use them as live bait. Release of live bait has been 
identified as a source for more than 100 introductions of fishes beyond 
their natural range in the United States. Although adult and market-
sized silver carp are fragile and do not survive collection and 
transport well, fingerling silver carp are less susceptible to 
mortality due to handling stress.
    Silver carp, caught as bycatch, may be sold as fillets or to live 
fish markets. Another potential pathway for further introductions is 
the intentional release of silver carp through animal rights activism 
or prayer release (the ceremonial release of a fish in honor of the one 
that will be eaten).
    Silver carp have survived, have become established in river 
systems, and have been reproducing in natural waters of the United 
States since at least 1995. Because silver carp can occupy lakes, there 
is serious concern that this species will further expand its range 
beyond riverine environments and into lake environments including the 
Great Lakes. If introduced, it is highly likely that silver carp will 
establish reproducing populations in other major river systems, such as 
the Potomac/Chesapeake, Columbia, and Sacramento/San Joaquin Delta. In 
their native range, juveniles and adults are also found in lakes, 
reservoirs, and canals where they grow well, but probably cannot spawn 
and recruit without access to an appropriate riverine habitat.


    Hybridization of silver carp with native fishes is not known to be 
possible, but silver carp are known to hybridize and produce viable 
offspring with both bighead carp (H. nobilis), a nonnative species also 
present in the Mississippi River basin, and largescale silver carp, a 
species not yet known to be in the United States. Bighead carp x silver 
carp and the reciprocal cross are fertile. Bighead carp x silver carp 
are common in parts of the United States. The presence of large numbers 
of wild-spawned hybrids implies that bighead and silver carp often 
spawn in the same place at the same time in United States waters. 
Silver carp x bighead hybrids adversely impact food availability for 
native species due to the size they attain and the amount of food they 
eat. Hybrids with largescale silver carp would likely adversely affect 
food availability for native species as well.
    Hybridization may also be possible with grass carp, but 
hybridization with common carp (Cyprinus carpio) is unlikely because 
the spawning locations and behaviors of the two genera are so 

Potential Effects on Native Species

    Silver carps' food consumption rate is high, but widely variable. 
Fry at the smallest size class consumed up to 140% of their body weight 
daily; 63 mg fingerlings consumed just more than 30% and 70-166 mg 
fingerlings consumed 63% of their body weight. Adult silver carp have 
been shown to consume 8.8 kilograms (kg) of food per year, with 90% of 
the consumption occurring during the three warmest months of the year.
    Silver carp are quite tolerant of broad water temperatures from 4 
[deg]C to 40 [deg]C. Silver carp can grow quickly (20 to 30

[[Page 37462]]

kg in 5 to 8 years), and large adults can reach over 1.2 meters in 
length and 50 kg in weight. Silver carp are difficult to age, but have 
been reported to live 15-20+ years.
    The reproductive potential of silver carp is high and increases 
with body size. It has been estimated that silver carp weighing 3.18 to 
12.1 kg can produce 145,000-5,400,000 eggs. Silver carp mature anywhere 
from 3-8 years, and males usually mature one year earlier than females. 
The same female may spawn twice during one growing season. Silver carp 
exhibit a prolonged spawning period, into late summer or early fall, in 
the United States.
    Due to the large size, fast growth rate, high food consumption rate 
and high reproductive potential of silver carp, competition for food 
and habitat with native planktivorous fishes and with post-larvae and 
early juveniles of most native fishes is likely high. Since nearly all 
larvae and juvenile fishes are planktivorous and based on other 
demonstrated impacts, it is highly likely that silver carp are 
adversely affecting many native fishes in the Mississippi River Basin, 
particularly in waters where food may become limited, though long-term 
studies have not yet been conducted. Affected native species include 
paddlefish (Polyodon spathula), bigmouth buffalo (Ictiobus 
cyprinellus), gizzard shad (Dorosoma cepedianum), emerald shiner 
(Notropis atherinoides), and threadfin shad (Dorosoma petenens). It is 
highly likely silver carp would adversely affect fishes in the Great 
Lakes basin or other watersheds, if they establish.
    Paddlefish, native to the Mississippi River Basin and Gulf of 
Mexico river drainages from east Texas to Alabama, is a large river 
fish that has declined in abundance in recent years because of 
overharvest and habitat alteration. Like the silver carp, paddlefish 
uses plankton as its primary food source, so silver carp or hybrids 
would directly compete with paddlefish for food throughout most of the 
paddlefish's range. Other fishes, such as buffalos or shads, use both 
plankton and aquatic invertebrates as food. While these fishes are 
currently more common than paddlefish, they may be at risk if silver 
carp, silver x largescale silver carp hybrids, or silver x bighead 
hybrids establish and reduce plankton. Gizzard shad are a primary 
forage base for predacious fishes and important to the ecology of 
Midwestern rivers; thus, the likely competition with silver carp in 
these waters is cause for concern.
    Because silver carp are likely to negatively affect important 
planktivorous forage fishes such as the gizzard shad and emerald 
shiner, scientists have indicated that fishes and birds that prey on 
these species would likely also be negatively affected. Adult silver 
carp are too large to be preyed on by almost any native predator. Young 
silver carp have likely been incorporated into the diets of piscivorous 
birds and fishes to some degree, but the extent of this predation is 
not known. Ecosystem balance is likely to be modified if silver carp 
populations become large enough to dominate other planktivorous fish 
species. The most likely negative effect would be an alteration of fish 
community structure through competition for food.
    Silver carp have been shown to have major effects on nutrient 
cycling and have had adverse effects on primary productivity, which 
could alter food webs and ultimately alter nutrient and energy cycling 
in aquatic communities. There is evidence of nutrient overloading in 
waters where silver carp have been introduced. Excrement from silver 
carp has been found to increase levels of certain nutrients, some which 
cannot be consumed by other animals in the digested form or may be 
harmful, which has led to a net decrease in food resources available in 
several studies. Recent studies on the effects of silver carp on toxin-
producing blue-green algae indicate that certain species of blue-green 
algae are often controlled by silver carp, but that other species are 
often enhanced, particularly those like Microcystis aeruginosa that 
have a mucosal covering that inhibits digestion by silver carp. These 
organisms can pass alive through the digestive tract and, in the 
process, acquire nutrients that can later be used for growth and cell 
division. Additionally, M. aeruginosa has been shown to produce more 
toxins in the presence of filter feeding fishes, especially silver 
carp. Once established, these fish are likely to cause shifts in the 
food web and compete with other zooplanktivorous fishes and fish larvae 
for food. Changes in the community structure towards smaller size 
plankton may have negative effects on fishes native to the United 
States that subsist on larger zooplankton.
    Adverse effects of silver carp on some threatened and endangered 
freshwater mussels and fishes are likely to be moderate to high. There 
are currently 116 fishes and 70 mussels on the Federal List of 
Endangered and Threatened Wildlife. Because silver carp have the same 
habitat requirements as approximately 40 fishes and 25 mussels 
currently on the endangered or threatened species list, these listed 
species will likely be impacted by competition for food and habitat by 
the introduction and establishment of silver carp.
    Habitat requirements, springs and small streams, of the remaining 
listed fishes and mussels would probably preclude any detectable 
effects as it is unlikely that silver carp could survive in such small 
bodies of water.
    Adverse effects of established populations of silver carp on 
endangered and threatened fishes would most likely be through direct 
competition for food resources, particularly phytoplankton and, to a 
lesser extent, zooplankton, in the water column during the larval 
stage. Potential for direct predation and injury of drifting fertilized 
eggs and larvae of native fishes also exists. The fact that silver carp 
can become extremely abundant and reach a very large size (> 1 m in 
length) in rivers, lakes, and reservoirs increases the probability of a 
negative impact on aquatic ecosystems they invade as high densities of 
silver carp decrease food availability for native species. Mussels are 
also filter feeders but live partly or totally buried in the substrate; 
their association with the benthic environment means that they would be 
less likely to be affected by filter-feeding silver carp. Nevertheless, 
changes in the fish community structure caused by silver carp are 
likely to have adverse effects on abundance and availability of host 
fishes required for mussel reproduction, which may result in a decline 
of native mussels.

Habitat Degradation

    There is low risk of silver carp causing direct habitat degradation 
or destruction, although the presence of silver carp is sometimes 
associated with decreased water clarity, which may also impact benthic 
chemistry and community structure. The effect of these fishes on 
nutrients, sediment re-suspension (which can stimulate plankton 
growth), and decreasing dissolved oxygen varies. Excrement from silver 
carp, which can equal their body weight in 10 days, has organically 
enriched lake bottoms and altered the benthic macroinvertebrate 
community structure.
    However, due to the impacts listed above, it is highly likely that 
silver carp would have adverse effects on designated critical habitats 
of threatened and endangered species. There are currently 60 species of 
fishes and 18 mussels with designated critical habitat. Of those, at 
least 26 inhabit lakes or reaches of streams large enough to support 
silver carp. Therefore, dense populations of silver carp are likely to 
affect the critical habitats upon which

[[Page 37463]]

the threatened and endangered species depend.

Potential Pathogens

    Many species of parasites and bacterial diseases occur in silver 
carp. The only viral disease agent of silver carp found in the 
literature is Rhabdovirus carpio, the causative agent for spring 
viraemia of carp (SVC), a systemic, acute, and highly contagious 
infection that is known to cause mortality in native fishes. Silver 
carp are susceptible to many diseases caused by parasitic protozoans 
and trematodes, and several crustacean parasites, such as anchor worm 
(Lernaea bhadraensis), have also been reported from silver carp.
    Although there have been studies of disease-causing agents of 
silver carp, none have investigated the transfer of these pathogens 
from silver carp to native fishes of the United States. However, two 
parasites known to infect silver carp are a threat to native North 
American fishes, including cyprinids: The gill-damaging Lernaea 
cyprinacea, known as anchorworm (this parasite is also known to affect 
salmonids and eels), and Bothriocephalus acheilognathi, known as Asian 
carp tapeworm. The Asian carp tapeworm, initially introduced into U.S. 
waters from grass carp, has infected native threatened and endangered 
fishes (including the yaqui chub (Gila purpurea), beautiful shiner, 
(Cyprinella formosa), yaqui topminnow (Poeciliopsis occidentalis 
sonoriensis), colorado pikeminnow (Ptychocheilus lucius), and humpback 
chub (G. cypha)) and fishes of concern such as the roundtail chub (G. 
robusta), a candidate for Federal listing as a threatened or endangered 
fish and listed as endangered by Colorado, in five States. When 
infected baitfish were released into Lake Mead, the tapeworm was spread 
to two endangered fishes, virgin spinedace (Lepidomeda mollispinis) and 
woundfin minnow (Plagopterus argentissimus) in Utah and Nevada. 
Approximately 90% of large juvenile and adult humpback chubs in the 
Little Colorado River are infected with this cestode. The Asian carp 
tapeworm has been reported from more than 40 other cyprinid fishes and 
fishes of other orders. Silver carp are hosts of this parasite, but 
suffer minimal adverse effects from it. As hosts of this tapeworm, 
silver carp have the potential to spread it to native fishes, beyond 
the five States where it has already been found (Arizona, Colorado, 
Nevada, New Mexico, and Utah). This is a parasite that erodes mucus 
membranes and intestinal tissues, often leading to death of the host. 
The most probable pathway of introduction was by the release of 
infected baitfishes. As the introduced range of silver carp grows in 
U.S. waters, silver carp will likely spread the parasite and a number 
of native fishes, particularly, but not limited to, cyprinids, percids, 
and centrarchids, will likely become hosts of the Asian carp tapeworm.
    Some disease-causing agents harbored by silver carp pose health 
risks to humans. The psychotropic pathogen Listeria monocytogenes has 
been found in market and fish farm samples of silver carp. Clostridium 
botulinum was found in 1.1% of fresh and smoked samples of silver carp 
from the Mazandaran Province in Iran. The toxigenic fungi Aspergillus 
flavus, Alternaria, Penicillium, and Fusarium were found from silver 
carp and from pond water in which they were raised at a fish farm in 
northern Iran. In addition, live Salmonella spp. can be found in silver 
carp for at least 14 days after transfer to clean water, and silver 
carp, therefore, should be considered as a potential carrier for 
Salmonella (S. typhimumium).

Impacts to Humans

    Silver carp in the United States cause substantial impacts to the 
health and welfare of human beings who use waterways infested with 
silver carp. There are numerous reports of injuries to humans and 
damage to boats and boating equipment because of the jumping habits of 
silver carp in the vicinity of moving motorized watercraft. Some 
reported injuries include cuts from fins, black eyes, broken bones, 
back injuries, and concussions. Silver carp also cause property damage 
including broken radios, depth finders, fishing equipment, and 
antennae. Some vessels have been retrofitted with a Plexiglas pilot's 
cab as protection against jumping silver carp.

Factors That Reduce or Remove Injuriousness for Silver Carp

Detection and Response

    If silver carp were introduced or spread into new U.S. waters, it 
is unlikely that the introduction would be discovered until the numbers 
were high enough to impact wildlife and wildlife resources. Widespread 
surveys of waterways are not conducted to establish species' presence 
lists. Delay in discovery would limit the ability and effectiveness to 
rapidly respond to the introduction and prevent establishment of new 
populations. It is unlikely that silver carp could be eradicated from 
U.S. waterways unless they are found in unconnected waterbodies.

Potential Control

    The ability to control spread of established populations depends on 
their access to open waterways and riverine habitat to spawn. Barriers 
may help control the spread of silver carp from the Mississippi River 
basin into the Great Lakes or other waterbodies, but barriers could 
also negatively affect migratory native fishes. There are still several 
pathways by which silver carp from established populations in the 
Mississippi River Basin might be moved to new waterbodies, such as the 
Potomac River or Columbia River, and become established.
    Due to the extensive established range of silver carp in the 
Mississippi River Basin, conventional control methods are not feasible 
to reduce established populations. Massive fishing efforts utilizing 
netting and electrofishing may be effective in reducing populations, 
but many non-target fish species would also be killed. Justifying the 
expense of such efforts would require a large commercial demand, which 
does not currently exist, nor is likely given the jumping behavior of 
silver carp that makes fishing difficult. Selective removal of silver 
carp is possible given their location in the water column, but water 
trawling could also remove other non-target fish such as paddlefish.
    The large and growing range of silver carp in U.S. waterways makes 
chemical control of established populations highly unlikely, both 
physically and fiscally. Use of chemical treatments, such as rotenone, 
would be expensive, only locally effective, and would negatively affect 
all fishes and invertebrates, not just the target carp. At present, 
there is no method known to substantially reduce established 
populations of silver carp. Eradication is not possible with presently 
available technology.

Recovery of Disturbed Sites

    Because the ability to eradicate this species is low, there is 
little likelihood for rehabilitation or recovery of ecosystems 
disturbed by this species. Additionally infested waterways allow 
connections to unpopulated sites. Utilizing sterile silver carp would 
do little to reduce or remove injuriousness as the present range of 
establishment in the Mississippi River Basin is too extensive for this 
option to reduce current silver carp populations in this area. The use 
of daughterless fish technology (introducing sterile males to produce 
unviable eggs) may reduce populations, but this would take many

[[Page 37464]]

years before it would reduce numbers of fish where they currently 
exist. Research is being conducted on the use of pheromones to control 
carp, but it is years from demonstrating effectiveness in natural 
waters and mass production. These technologies might be useful to 
prevent establishment of silver carp in new areas.

Potential Pathogens

    Silver carp are host to many parasites and bacterial diseases that 
are or could be a threat to native North American fishes. If silver 
carp transfer pathogens to native fish, the ability and effectiveness 
to control these transfers would be very low because silver carp and 
native fishes share the same habitat.

Potential Ecological Benefits for Introduction

    The ability of silver carp to effectively filter particles and 
reliance on phytoplankton for much of its diet led to research into 
their effectiveness as a biological control agent for phytoplankton in 
wastewater systems and other ponds. There is conflicting data 
concerning the benefit of using silver carp to control excess 
nutrients. Regardless of their effect on increasing or decreasing 
phytoplankton and zooplankton abundance, studies have consistently 
shown that filter feeding by silver carp shifts the species composition 
of these communities to smaller species. Silver carp have been observed 
to cause nuisance algal blooms through a trophic cascade. Scientists 
believe that the removal of larger zooplankton and phytoplankton by 
foraging silver carp may result in stimulating growth of smaller 
    In summary, the Service finds all forms of live silver carp, 
including gametes, viable eggs and hybrids, to be injurious to wildlife 
and wildlife resources of the United States and to the interests of 
human beings because:
     Silver carp are highly likely to spread from their current 
established range to new waterbodies in the United States;
     Silver carp are highly likely to compete with native 
species, including threatened and endangered species, for food and 
     Silver carp have the potential to carry pathogens and 
transfer them to native fish;
     Silver carp are likely to develop dense populations that 
will likely affect critical habitat for threatened and endangered 
species and could further imperil other native fishes and mussels;
     Silver carp are negatively impacting humans;
     It would be difficult to eradicate or reduce large 
populations of silver carp, or recover ecosystems disturbed by the 
species; and
     There are no potential ecological benefits for U.S. waters 
from the introduction of silver carp.

Factors That Contribute to Injuriousness for Largescale Silver Carp

Potential Introduction and Spread

    To our knowledge, the largescale silver carp has not been imported 
into the United States. Within its native range, largescale silver carp 
occur in subtropical to tropical climates, which exist in parts of the 
United States. Therefore, should pure largescale silver carp be 
introduced to U.S. waters, its potential range would likely include 
subtropical waters such as those present in southern Florida, southern 
Texas, and Hawaii.
    The growth rate of largescale silver carp is greater than that of 
silver carp. The reproductive capability is expected to be similar to 
that of silver carp, though largescale silver carp reach sexual 
maturity at a younger age than silver carp so they will spawn earlier.
    In culture situations, silver carp has hybridized with largescale 
silver carp. The hybrids did not grow as quickly as largescale silver 
carp but exceeded the growth rate of silver carp. Largescale silver 
carp x silver carp hybrids were introduced in Kazakhstan where they 
became established. The climate of Kazakhstan is temperate; thus, 
largescale silver carp x silver carp hybrids are more cold-tolerant 
than pure largescale silver carp. The faster growth rate of these 
hybrids than pure silver carp and the increased palatability of 
largescale silver carp compared to silver carp may conceivably 
stimulate interest in culturing either the hybrids or pure largescale 
silver carp in the United States. Because hybrids can tolerate 
temperate climates, they have the potential to be cultured in many 
southern States and would have a wider potential range where they could 
establish in the United States.
    Escape from containment, as has happened with silver carp, would 
provide a pathway for release of largescale silver carp into natural 
waters of the United States. Should this fish or its hybrids be 
released into natural waters, connected waterways would become a 
secondary pathway for spread. Because of the morphological similarity 
between this species and silver carp, stock contamination of silver 
carp by largescale silver carp is possible if imported from regions 
with populations of H. harmandi. Another possible introduction pathway, 
should largescale silver carp or their hybrids be imported for culture, 
would be sale of live individuals in food fish markets.
    Likelihood of spread of largescale silver carp, should they be 
introduced, would be high in subtropical and tropical river systems of 
the United States. Hybrid largescale silver carp x silver carp, 
however, would have high potential to live in much of the temperate 
United States. Because largescale silver carp can occupy and reproduce 
in reservoirs, they could also live in lakes. The same is likely true 
for hybrids. Young largescale silver carp or any hybrids captured by 
anglers for use as live bait would be a pathway that could lead to 
numerous future introductions of these species.


    Hybridization with native fishes is not believed to be possible, 
but largescale silver carp are known to hybridize and to produce viable 
offspring with silver carp and possibly bighead carp, both of which are 
present in U.S. waters. Largescale silver x silver carp hybrids are 
tolerant of a temperate climate (ca. 42-46[deg] N). (45[deg] N is a 
latitude that parallels the border between New York State and Ontario, 
Canada). Therefore, these hybrids would likely be capable of surviving 
and probably establishing throughout much of the United States where 
suitable waters exist. Largescale silver carp grow faster than silver 
carp but hybrids do not grow as quickly as pure largescale silver carp. 
It is highly likely that any largescale silver carp hybrids would 
directly compete with native species for food and habitat.

Potential Effects on Native Species

    Largescale silver carp consume primarily planktonic food sources. 
It is unknown if largescale silver carp feed more heavily on 
phytoplankton than zooplankton, but their hybrids with silver carp 
would likely show a preference for phytoplankton. Some adults may weigh 
20-30 kg. The rapid growth and high fat content of this fish has made 
it the most cultured species for food in Vietnam. Largescale silver 
carp and hybrids are highly likely to compete for food with other 
planktivorous native fishes and with post-larvae and early juveniles of 
most native fishes should they become established in the United States.
    Fishes most likely to be affected are those species whose diet is 
predominantly plankton including paddlefish (Polyodon spathula), native

[[Page 37465]]

to the Mississippi River Basin and Gulf of Mexico river drainages from 
east Texas to Alabama, buffalos (Ictiobus spp.), or shads (Dorosoma 
spp.). Given that these fish may already be competing with bighead and 
silver carps in some areas, the presence of largescale silver carp 
would increase food competition and increase the likelihood of negative 
impacts to native species.
    Potential for direct predation and injury of drifting fertilized 
eggs and larvae of fishes exists. Mussels are also filter feeders but 
live partly or totally buried in the substrate; they would be less 
likely to be affected by water column filter-feeding largescale silver 
carp. Nevertheless, changes in the fish community structure caused by 
largescale silver carp would likely have adverse effects on abundance 
and availability of host fishes required for mussel reproduction.
    There are other possible, but less likely, effects that may cascade 
through any aquatic ecosystem with an established population of 
largescale silver carp. Nutrient levels are a concern because there is 
evidence of overloading of nutrients in waters into which silver carp 
have been introduced, and the same may apply to largescale silver carp 
or their hybrids.
    Competition for habitat between largescale silver carp and native 
species is likely high, especially in large rivers, lakes, and 
reservoirs. Because they are planktivorous, the potential of largescale 
silver and any hybrids to cause habitat degradation or destruction is 
low as is direct predation on native mammals, birds, amphibians, 
reptiles, mollusks or other live, non-aquatic animals.
    Additional adverse impacts on native wildlife, wildlife resources, 
and ecosystem balance are likely few, except for fishes. Ecosystem 
balance would likely be modified if populations of largescale silver 
carp or any hybrids become large enough to dominate planktivorous fish 
    Because largescale silver carp may survive and become established 
and compete with native fishes, there is no acceptable escape or 
release threshold for largescale silver carp or their hybrids.
    Adverse effects of largescale silver carp on selected threatened 
and endangered freshwater mussels and fishes would be expected to be 
moderate to high. There are currently 116 fishes and 70 mussels on the 
Federal List of Endangered and Threatened Wildlife. Because largescale 
silver carp have the same habitat requirements as approximately 40 
fishes and 25 mussels currently on the endangered or threatened species 
list, these listed species in tropical or subtropical areas will likely 
be impacted by the introductions of largescale silver carp through 
competition for food and habitat. However, the habitat requirements, 
springs and small streams, of the remaining listed fishes and mussels 
would probably preclude any detectable effects as it is unlikely that 
largescale silver carp or their hybrids would survive in such small 
bodies of water.
    It is likely that largescale silver carp and highly likely that 
their hybrids with silver carp would have adverse effects on designated 
critical habitats of threatened and endangered species. There are 
currently 60 species of fishes and 18 mussels with designated critical 
habitat. At least 26 fishes and mussels with critical habitat inhabit 
lakes or reaches of streams large enough to support hybrids of 
largescale silver carp and silver carp. Largescale silver carp and 
their hybrids have the potential to alter food webs and ultimately 
alter nutrient and energy cycling in aquatic communities. The most 
likely effect would be an alteration of fish community structure 
through competition for food. Fishes and mussels that are determined to 
be candidates for listing under the Endangered Species Act would 
likewise be at risk.
    Native species may be placed in danger of extinction as a result of 
the introduction or establishment of largescale silver carp if pure 
stock became established in subtropical or tropical waters in the 
United States. However, there is a higher risk for negative impacts to 
native fishes from largescale silver carp hybrids. Large populations of 
largescale silver carp or hybrids would likely alter native fish 
community structures, ultimately resulting in decline of native mussels 
since many rely on native host fishes for reproduction. The fact that 
largescale silver carp have the potential to become abundant and reach 
a very large size (> 1 m in length) in rivers, lakes, and reservoirs 
increases the probability of a negative impact on aquatic ecosystems 
should largescale silver carp be introduced and become established.

Potential Pathogens

    The potential for largescale silver carp to transfer pathogens is 
largely unknown. No detailed studies of disease-causing agents of 
largescale silver carp have been found, but at least three trematode 
parasites (Dactylogyrus harmandi, D. hypophthalmichthys, D. 
chenthushenae) are known to infect largescale silver carp. Bighead, 
silver, grass, and black carps are known to host the Asian carp 
tapeworm (Bothriocephalus acheilognathi), but it is unknown whether 
largescale silver x silver carp host this species. Since largescale 
silver carp are very similar to silver carp, they likely can host the 
Asian carp tapeworm and infected fish, if introduced to U.S. waters, 
could spread it to native fishes.

Potential Impacts to Humans

    The potential impact on the health and welfare of humans from 
largescale silver carp or any hybrids is unknown. Because largescale 
silver carp remain deep in the water column during daylight hours and 
swim toward the surface at night to feed on plankton, they may be less 
prone to jumping than silver carp in response to sounds of boat engines 
during daytime. However, if largescale silver x carp hybrids display 
the jumping behavior of pure silver carp, their potential to injure 
humans could be considerable.

Factors That Reduce or Remove Injuriousness for Largescale Silver Carp

Detection and Response

    If largescale silver carp were introduced into U.S. waters, it is 
unlikely that the introduction would be discovered until the numbers 
were high enough to impact wildlife and wildlife resources. Widespread 
surveys of waterways are not conducted to establish species' presence 
lists. Delay in discovery would limit the ability and effectiveness to 
rapidly respond to the introduction and prevent establishment.

Potential Control

    If largescale silver carp were to escape and become established in 
natural waters, management of established populations would be highly 
unlikely both physically and fiscally. Some control might be possible 
with massive fishing efforts using nets, but this is unlikely to stem 
range expansion. There would have to be substantial commercial demand 
to justify the expense of such efforts.
    Chemicals or selective removal may be used to manage populations in 
localized areas. However, selective removal of largescale silver carp 
would be difficult because they remain in deeper waters during daylight 
hours when such removal efforts would probably occur. Pheromones may be 
a viable option to limit spread; this possibility is under 
investigation for silver carp, and may have applicability to largescale 
silver carp.
    However, research into this control method is in early stages.

[[Page 37466]]

    Because no evidence exists that largescale silver carp have been 
imported or released into U.S. waters, triploidy or induced sterility 
could potentially reduce injuriousness. However, these processes are 
costly, time-consuming, and not 100% effective so there is potential 
for triploid largescale silver carp to cause harm if they were 
    It would be difficult to control the spread of largescale silver 
carp to new locations except, perhaps, by use of electric, acoustic, 
physical and other types of barriers. At present, there is no method 
known to substantially reduce populations of introduced fishes in U.S. 
waterways. It is highly unlikely that largescale silver carp could be 
eradicated from U.S. waterways, should they be introduced, unless they 
are found in unconnected waterbodies.

Recovery of Disturbed Sites

    Although there is no evidence that this species has been introduced 
or targeted for introduction into the United States, the lack of 
available methods to detect, eradicate or control introduced 
populations indicates that should largescale silver carp be introduced, 
rehabilitation or recovery of ecosystems disturbed by this species 
would be highly unlikely.

Potential Pathogens

    The potential for largescale silver carp or any hybrids to infect 
native fishes with pathogens is largely unknown. Should such transfers 
prove viable, the ability and effectiveness to control the spread of 
pathogens to native fishes would be low.

Potential Ecological Benefits for Introduction

    There are no potential ecological benefits for introduction of 
largescale silver carp or any hybrids in natural waters of the United 
    In summary, the Service finds all forms of live largescale silver 
carp, including gametes, viable eggs and hybrids, to be injurious to 
the wildlife and wildlife resources of the United States and to the 
interests of human beings because:
     Largescale silver carp are likely to escape or be released 
into the wild if imported into the United States;
     Largescale silver carp are highly likely to survive, 
become established, and spread in tropical or subtropical areas of the 
United States if they escape or are released;
     Largescale silver carp would likely carry pathogens that 
could be transferred to native fish;
     Largescale silver carp and hybrids are likely to compete 
with native species, including threatened and endangered species, for 
food and habitat;
     Largescale silver carp could develop dense populations 
that would likely affect critical habitat for threatened and endangered 
species and are highly likely to negatively impact native fishes and 
     Largescale silver carp have been shown to hybridize with 
silver carp, a nonnative species already established in the United 
States, and would likely have a larger range than pure largescale 
silver carp;
     Largescale silver carp hybrids with silver carp may 
display jumping behavior that could injure humans;
     If largescale silver carp were introduced into the United 
States, it would be extremely difficult to prevent their spread and to 
control populations in natural waters;
     It would be difficult to eradicate or reduce large 
populations of largescale silver carp and to recover ecosystems 
disturbed by the species; and
     There are no potential ecological benefits from the 
introduction of largescale silver carp for U.S. waters.

Required Determinations

Paperwork Reduction Act (44 U.S.C. 3501 et seq.)

    This rule contains potential information collection activity for 
FWS Form 3-200-42, Import/Acquisition/Transport of Injurious Wildlife. 
Completion of this form would be necessary to apply for a permit to 
import, or transport across State lines, any live silver or largescale 
silver carp, gametes, viable eggs, or hybrids for scientific, medical, 
educational, or zoological purposes. The Service already has approval 
from the Office of Management and Budget (OMB) to collect information 
for this special use permit under OMB control number 1018-0093. This 
approval expires July 31, 2007. The Service may not conduct or sponsor, 
and a person is not required to respond to, a collection of information 
unless it displays a currently valid OMB control number.

Regulatory Planning and Review

    (a) In accordance with the criteria in Executive Order 12866, OMB 
has designated this rule as a significant regulatory action.
    This rule will not have an annual economic effect of $100 million 
or more or adversely affect an economic sector, productivity, jobs, the 
environment, or other units of the government. A brief assessment to 
clarify the costs and benefits associated with this rule follows.
Costs Incurred
Silver Carp
    We expect this rule to have minimal costs. Silver carp are not 
cultured in the United States, nor do we believe that they are imported 
or exported. Currently, there are some commercial fisheries for silver 
carp in the Mississippi, Missouri, and Illinois rivers. Usually, 
commercial fishermen are catching silver carp as bycatch, which can 
account for up to 50 percent of the catch. Silver carp are not 
favorable because of their jumping habits and because they are less 
desirable by the consumer. In Missouri, many of the fishermen do not 
primarily target Asian carp (bighead and silver carp) because the price 
received is low ($0.10-$0.15 per pound). Instead, they fish for bighead 
and silver carp when other species or opportunities are unavailable. 
Many fishermen do not distinguish between bighead carp and silver carp.
    Data for the silver carp fishery are limited. According to public 
comments received, small commercial fisheries for silver carp exist in 
Illinois, Iowa, and Kentucky. Table 1 shows commercial fishery landings 
and value in Iowa and Illinois in 2003. Compared to the total 
commercial harvest and value, Asian carp represented 11 percent of 
landings and 6 percent of value in 2003. Because Illinois does not 
distinguish between bighead carp and silver carp in its annual report, 
we are unable to determine the magnitude of silver carp landings for 
the entire area. For Iowa, silver carp represented less than 1 percent 
of total landings. In 2005, silver carp represented less than 1 percent 
of commercial landings in Kentucky and less than one-tenth of 
commercial landings in Louisiana (public comments, J. Gassett 25 Oct 
2006 and J. Roussel 6 Nov 2006).
    The majority of the silver carp catch is sold as round weight. In 
Illinois, fishermen can sell silver carp as long as they are not 
transported live once the fish are taken off the water. No impacts are 
expected to the silver carp market because they are not delivered live.

[[Page 37467]]

                    Table 1.--2003 Commercial Fishery Landings and Value in Iowa and Illinois
                                                                   Illinois \1\     Iowa \2,3\         Total
Total Commercial Harvest (lbs)..................................       6,385,473       2,242,997       8,628,470
    Asian Carp*.................................................         900,497          15,774         916,271
    Silver Carp.................................................  ..............           3,828           3,828
Total Commercial Value ($)......................................      $1,334,467        $496,765      $1,831,232
    Asian Carp*.................................................         $99,055          $1,735        $100,790
    Silver Carp.................................................  ..............            $421            $421
\*\ Asian carp includes bighead carp and silver carp. The value for Asian carp and silver carp in Iowa is based
  on the average $0.11/lb received, which is the same as Illinois.
\1\ Illinois Department of Natural Resources. 2005. 2003 Commercial Catch Report. Brighton, Illinois.
\2\ Personal communication, Gene Jones, Iowa Department of Natural Resources.
\3\ Iowa Department of Natural Resources. 2003. Fisheries Management Section 2003 Completion Reports. Des
  Moines, Iowa.

    The market for live silver carp in U.S. markets is unknown and no 
public comments received reported a U.S. market for live silver carp. 
It is possible that silver carp are inadvertently shipped along with 
live bighead carp. However, most live haulers will not haul live silver 
carp because the fish do not transport well. Furthermore, the consumer 
prefers bighead carp to silver carp. Because only sales of live silver 
carp would be regulated by this rulemaking, we do not expect any 
impacts to commercial fishermen unless they are transporting live 
silver carp across State lines for processing. While the exact impact 
is unknown, we expect it to be minimal.
Largescale Silver Carp
    There is no known use for largescale silver carp in the United 
States or import or export of the species into or from the United 
States. We do not know of any future plans to use largescale silver 
carp in the United States. During the public comment period, no 
comments reported largescale silver carp being used. Therefore, we do 
not expect the rule to add largescale silver carp to the list of 
injurious wildlife to have any costs.
Benefits Accrued
Silver Carp
    Within several waters of the Midwest, silver carp comprise a 
percentage of the commercial catch as bycatch (non-target species). 
This may be negatively impacting revenue for commercial fishermen 
because silver carp are not as valuable as the native species that are 
    Furthermore, it is possible that silver carp populations will be 
delayed or not become established in new watersheds (Columbia Basin, 
Chesapeake Basin, and Sacramento-San Joaquin Delta) with similar 
attributes as the Mississippi River Basin as a result of this 
rulemaking. Silver carp are likely to compete with native fish for 
food, causing declines in native fishes in the United States, 
particularly those that rely heavily on plankton as a food resource.
    Thus, this rule will protect native fish, and the recreational and 
commercial fisheries associated with native fish. In terms of 
recreational fisheries, benefits would accrue due to (1) consumer 
surplus generated from fishing native fish and (2) fishing-related 
expenditures such as food, lodging, and equipment. In terms of 
commercial fisheries, benefits would accrue due to the revenue from 
fishing native fish, which are more valuable than silver carp. The 
timeline for when these benefits would accrue depends on the potential 
spread and impacts of silver carp. The extent of benefits to 
recreational and commercial fisheries is unknown.
Largescale Silver Carp
    There have been no reports that largescale silver carp are in the 
United States. However, native fish populations are likely to decline 
if largescale silver carp were to establish populations in the United 
States. With this rule, we reduce the risk of the introduction and 
establishment of largescale silver carp (or any hybrids) in U.S. 
watersheds. Thus, this rule protects native fish and the recreational 
and commercial fisheries associated with native fish. In terms of 
recreational fisheries, benefits would accrue due to the continued (1) 
consumer surplus generated from fishing native fish and (2) fishing-
related expenditures such as food, lodging, and equipment. In terms of 
commercial fisheries, benefits would accrue due to the continued 
revenue from fishing native fish. The extent of benefits to 
recreational and commercial fisheries is unknown because it depends on 
the introduction and subsequent establishment of largescale silver carp 
populations in the United States.
    (b) This rule will not create inconsistencies with other Federal 
agencies' actions. This rule pertains only to regulations promulgated 
by the Service under the Lacey Act. No other agencies are involved in 
these regulations.
    (c) This rule will not materially affect entitlements, grants, user 
fees, loan programs, or the rights and obligations of their recipients. 
This rule does not affect entitlement programs. This rule is aimed at 
regulating the importation and movement of nonindigenous species that 
cause or have the potential to cause significant economic and other 
impacts on natural resources that are the trust responsibility of the 
Federal Government.
    (d) OMB has determined that this rule raises novel legal or policy 

Regulatory Flexibility Act

    Under the Regulatory Flexibility Act (as amended by the Small 
Business Regulatory Enforcement Fairness Act (SBREFA) of 1996), 
whenever a Federal agency publishes a notice of rulemaking for any 
proposed or final rule, it must prepare and make available for public 
comment a regulatory flexibility analysis that describes the effect of 
the rule on small entities (i.e., small businesses, small 
organizations, and small government jurisdictions) (5 U.S.C. 601 et 
seq.). However, no regulatory flexibility analysis is required if the 
head of an agency certifies that the rule would not have a significant 
economic impact on a substantial number of small entities. Thus, for a 
regulatory flexibility analysis to be required, impacts must exceed a 
threshold for ``significant impact'' and a threshold for a 
``substantial number of small entities.'' See 5 U.S.C. 605(b). SBREFA 
amended the Regulatory Flexibility Act to require Federal agencies to 
provide a statement of the factual basis for certifying that a rule 
would not have a significant economic impact on a substantial number of 
small entities.
    This rulemaking may impact a small number of fishermen selling live 
silver carp. The number of fishermen targeting silver carp is unknown. 
Because the

[[Page 37468]]

market for live silver carp is also unknown, we are unable to estimate 
the degree of impact of this rulemaking. We expect this rulemaking to 
have a minimal effect on commercial fishermen selling live silver carp 
because many live haulers do not transport live silver carp. We do not 
expect this rulemaking to affect aquaculture because silver carp, 
largescale silver carp, or any hybrids are not being cultured in the 
United States at this time.
    Many small businesses within the retail trade industry (such as 
hotels, gas stations, taxidermy shops, bait and tackle shops, etc.) may 
benefit from continued recreational fishing without impacts from silver 
carp, largescale silver carp, or any hybrids. Furthermore, small 
businesses associated with commercial fishing (fishermen, wholesalers, 
and retailers) will also benefit from continued commercial fishing 
without impacts from silver carp, largescale silver carp, or any 
hybrids. We do not know the extent to which these small businesses will 
continue to benefit. However, we expect this benefit to be distributed 
across various watersheds, and so we do not expect that the rule will 
have a significant economic effect (benefit) on a substantial number of 
small entities in any region or nationally.
    Therefore, we certify that this rule will not have a significant 
economic effect on a substantial number of small entities as defined 
under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.). An initial 
or final Regulatory Flexibility Analysis is not required. Accordingly, 
a Small Entity Compliance Guide is not required. For the reason 
described below, no individual small industry within the United States 
will be significantly affected if silver carp or largescale silver carp 
importation is prohibited.

Small Business Regulatory Enforcement Fairness Act

    The rule is not a major rule under 5 U.S.C. 804(2), the Small 
Business Regulatory Enforcement Fairness Act. This rule:
    (a) Does not have an annual effect on the economy of $100 million 
or more. Silver carp is in limited commercial trade in the United 
States and primarily as fillets; the largescale silver carp is not 
known to be imported or present in the United States. Silver carp are 
likely to negatively affect many native fishery resources if they 
continue to spread in the United States. The largescale silver carp 
could devastate many native fishery resources if it is introduced to 
U.S. waterways. This rulemaking will protect the environment from the 
introduction and spread of nonnative species and will indirectly work 
to sustain the economic benefits enjoyed by numerous small 
establishments connected with recreational and commercial fishing.
    (b) Will not cause a major increase in costs or prices for 
consumers, individual industries, Federal, State, or local government 
agencies, or geographic regions.
    (c) Does not have significant adverse effects on competition, 
employment, investment, productivity, innovation, or the ability of 
U.S.-based enterprises to compete with foreign-based enterprises.

Unfunded Mandates Reform Act

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), this rule does not impose an unfunded mandate on State, 
local, or tribal governments or the private sector of more than $100 
million per year. The rule would not prohibit intrastate transport or 
any use of silver carp or largescale silver carp within State 
boundaries. Any regulations concerning the use of silver carp or 
largescale silver carp within individual States will be the 
responsibility of each State. The rule does not have a significant or 
unique effect on State, local, or tribal governments or the private 
sector. A statement containing the information required by the Unfunded 
Mandates Reform Act is not required.


    In accordance with Executive Order 12630, the rule does not have 
significant takings implications. A takings implication assessment is 
not required. This rule would not impose significant requirements or 
limitations on private property use.


    In accordance with Executive Order 13132, the rule does not have 
significant Federalism effects. A Federalism assessment is not 
required. This rule would not have substantial direct effects on 
States, in the relationship between the Federal government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government. Therefore, in accordance with Executive 
Order 13132, we determine that this rule does not have sufficient 
Federalism implications to warrant the preparation of a Federalism 

Civil Justice Reform

    In accordance with Executive Order 12988, the Office of the 
Solicitor has determined that the rule does not unduly burden the 
judicial system and meets the requirements of sections 3(a) and 3(b)(2) 
of the Executive Order. The rule has been reviewed to eliminate 
drafting errors and ambiguity, was written to minimize litigation, 
provides a clear legal standard for affected conduct rather than a 
general standard, and promotes simplification and burden reduction.

National Environmental Policy Act

    We have prepared environmental assessments (EAs) in conjunction 
with this rulemaking, and have determined that this rulemaking is not a 
major Federal action significantly affecting the quality of the human 
environment within the meaning of section 102(2)(C) of the National 
Environmental Policy Act (NEPA of 1969 (42 U.S.C. 4321 et seq.)). No 
comments on the draft environmental assessments were received. For 
copies of the final EAs, contact the individual identified above in the 
section FOR FURTHER INFORMATION CONTACT, or access the documents at 

    Adding silver carp and largescale silver carp to the list of 
injurious wildlife is intended to prevent their further introduction 
and establishment into natural waters of the United States in order to 
protect native fishes, the survival and welfare of wildlife and 
wildlife resources, and the health and welfare of humans. Not listing 
silver carp as injurious may allow for an expansion to States where 
they are not already found, thus increasing the risk of their escape 
and establishment in new areas due to accidental release and, perhaps, 
intentional release. Their establishment is negatively impacting native 
fish, wildlife, and humans. Silver carp are established throughout much 
of the Mississippi River Basin. Releases of silver carp into natural 
waters of the United States are likely to occur again, and the species 
is likely to become established in additional U.S. waterways, 
threatening native fish populations, wildlife, and wildlife resources 
dependent on phytoplankton, zooplankton, bacteria, and detritus, and 
impacting human health.
    Largescale silver carp are not known to be in the United States, 
but if introduced to natural waters, they would likely impact the 
welfare and survival of native fish and wildlife, as well as the health 
and welfare of humans. In addition, largescale silver carp are visually 
similar to silver carp and can readily hybridize with silver carp, so 
they would be difficult to distinguish from silver carp.

[[Page 37469]]

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994, 
``Government-to-Government Relations with Native American Tribal 
Governments'' (59 FR 22951), Executive Order 13175, and 512 DM 2, we 
have evaluated potential effects on Federally recognized Indian tribes 
and have determined that there are no potential effects. This rule 
involves the importation and interstate movement of all forms of live 
silver carp, largescale silver carp, gametes, viable eggs, and hybrids. 
We are unaware of trade in these species by Tribes.

Effects on Energy

    On May 18, 2001, the President issued Executive Order 13211 on 
regulations that significantly affect energy supply, distribution, and 
use. Executive Order 13211 requires agencies to prepare Statements of 
Energy Effects when undertaking certain actions. This rule is not 
expected to affect energy supplies, distribution, and use. Therefore, 
this action is a not a significant energy action, and no Statement of 
Energy Effects is required.

References Cited

    A complete list of all references used in this rulemaking is 
available upon request from the Branch of Invasive Species (see the FOR 

List of Subjects in 50 CFR Part 16

    Fish, Imports, Reporting and recordkeeping requirements, 
Transportation, Wildlife.

For the reasons discussed in the preamble, the U.S. Fish and Wildlife 
Service amends part 16, subchapter B of Chapter I, Title 50 of the Code 
of Federal Regulations, as set forth below.


1. The authority citation for part 16 continues to read as follows:

    Authority: 18 U.S.C. 42.

2. Amend Sec.  16.13 as follows:
a. By removing the word ``and'' at the end of paragraph (a)(2)(iii);
b. By removing the period at the end of paragraph (a)(2)(iv)(BB) and 
adding in its place ``; and'' ; and
c. By adding a new paragraph (a)(2)(v) to read as set forth below.

Sec.  16.13  Importation of live or dead fish, mollusks, and 
crustaceans, or their eggs.

    (a) * * *
    (2) * * *
    (v) Any live fish, gametes, viable eggs, or hybrids of the species 
silver carp, Hypophthalmichthys molitrix, and largescale silver carp, 
Hypophthalmichthys harmandi.
* * * * *

    Dated: May 18, 2007.
Todd Willens,
Acting Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. E7-13371 Filed 7-9-07; 8:45 am]