resources. The Service regional archaeologist has reviewed the proposed action and
determined eradication operations will not cause adverse effects to cultural and/or
historic sites. The proposed action is also being reviewed by the State Historical
Preservation Officer. If needed, further consultation will take place to ensure effects on
historic properties are fully considered as required by Section 106 of the National
Historic Preservation Act. Additionally, we must comply with federal regulations
relating to the protection of historic or archaeological sites.

6. Restoration of Biodiversity

Rat Island was selected for the proposed action because it is the smallest uninhabited
refuge island with an invasive rat population that will not be re-invaded by rats from
nearby islands after eradication. There are other smaller refuge islands with introduced
rats, but rats on nearby islands may disperse and re-occupy soon after eradication. Larger
uninhabited rat-invaded refuge islands have more diverse non-target risks, greater
diversity of habitat that can support rats, and are bigger than the largest successful rat
eradication in the world making them more difficult to treat. There are virtually no
seabirds nesting on Rat Island and relatively few birds of any kind. The intent of
restoring the natural ecosystem function on Rat Island is to re-establish native seabirds
and other native species, thus returning this wilderness island to a healthy natural
community. The recovery of other Aleutian Islands after fox eradication and the
recovery of other islands after rat eradication give us confidence that native wildlife and
plants will be restored on Rat Island after rats are removed. The protection of natural
biodiversity is mandated by the Alaska National Interest Lands Conservation Act
(ANILCA), Service policy, and other legal authorities. The proposed action reinforces
these mandates.

7. Rodenticide Approval

The EPA is currently considering Federal Insecticide, Fungicide and Rodenticide Act
(FIFRA), Section 3 registration for a bait containing brodifacoum for conservation
purposes; the selected rodenticide for this action. The proposed registration is very
specific and allows use of the product only according to label directions. Currently there
is no other existing or proposed federal registration of brodifacoum for application by
aerial broadcast. There is a FIFRA Section 3 registration for diphacinone for
conservation purposes that allows aerial broadcast, but we are aware of only five times
this active ingredient has been used for island eradication of rats, and never by broadcast
technique. The proposed action will pose minimal risk to the public health and safety.
The risk to the public from applying brodifacoum rodenticide in a manner approved by
EPA is negligible.

8. Significance of the Action to Rat Island Wildlife

The EA considers the proposed action in both context and intensity of impacts on
individuals as well as populations of non-target species. The proposed action is intended


acceptable to gain long-term benefits to the island ecosystem as a result of the proposed
action. Furthermore, negative population level effects are not expected for any native
species or subspecies in the Rat Islands group. Worldwide, rats have caused the
extirpation and extinction of native and endemic taxa on a number of islands. The
negative impacts of rats and other non-native predators (such as arctic fox) on native
species have been documented in the Aleutian Islands (e.g., Bailey 1993, Byrd et.
al.1994, Ebbert and Byrd 2002), as have the cascade effect on island ecosystems (Croll
et. al., 2005). Therefore, removal of rats from Rat Island to allow for restoration of
native biodiversity is a positive management action.

3. Seasonal Timing of the Action

One comment pertained to the seasonal timing of the proposed action. The timing of the
proposed action was chosen to balance three factors: rat biology, impact on non-target
species, and safety of personnel. The objective is to maximize efficacy on rats (i.e.,
eradication) within a seasonal timing window that minimizes disturbance to non-target
species (by conducting operations outside the summer peak of wildlife breeding seasons)
and avoid periods when winter conditions increase safety issues for personnel and/or
compromise bait availability due to snow or ice cover. Rat eradication using broadcast
baits on top of, or during, snow has never been attempted, and its probability of success is
unknown. The timing window for the proposed action will be from approximately
October 1 (after most bird and marine mammal breeding has been completed) until the
first snowfall of the winter (see EA for more details). This is also a time period when the
reproductive season for rats is waning. According to historical weather data for the
region, it will be feasible to have enough flying days to complete bait broadcasts prior to
snowfall.

4. Marine Mammal Disturbance

Aleutian-region marine mammals, including Steller sea lions, northern sea otters, and
harbor seals are protected by the Marine Mammal Protection Act. Steller sea lions and
northern sea otters are also protected by the Endangered Species Act (ESA). The project
will not occur unless we have satisfied all legal requirements for these species prior to the
proposed action. The process ensures the procedures and methods of the proposed action
are reviewed by the responsible agencies. To minimize potential impacts on individual
Steller sea lions, the proposed action includes special treatment of the small rocky islet
southeast of Ayugadak Point which hosts a small Steller sea lion rookery. If weather
allows, bait stations will be deployed on the islet as early as August 2008 in lieu of a
helicopter broadcast later. Broadcast of bait on the islet will occur if weather does not
permit access prior to the aerial broadcast of bait on Rat Island.

5. Cultural Site Protection
There are no unique characteristics such as cultural, traditional, or historic sites or

ecologically critical areas that will be adversely affected. Adherence to existing laws and
regulations will further ensure that the eradication operation does not harm the cultural


to have lethal impacts on the target species (rats), and will also have limited impacts on
other individual animals, including mortality. However, wildlife populations will not be
affected globally or regionally. Individual animals that are afforded special regulatory
protection and/or are thought to be particularly rare or vulnerable will not be adversely
affected by the action. We have the same accountability not to disturb threatened and
endangered species; it is evaluated similarly on and off the refuge. The proposed action
will be reviewed by the appropriate agencies with authority to permit the proposed action.
The project cannot proceed without their concurrence; the proposed action will not cause
significant damage to threatened or endangered species.

FINDING OF NO SIGNIFICANT IMPACT

Based on a review and evaluation of the information contained in the EA and in the
supporting references listed below, I have determined that the proposed project is not a
major federal action that would significantly affect the quality of the human environment
as defined in Section 102 (2)c of the National Environmental Policy Act of 1969. This
determination is made after full consideration of the context and intensity of the project.
There are no known irreversible or irretrievable commitments of resources. The analysis
of the EA indicates there will not be a significant impact, individually or cumulatively, on
the quality of the human environment. The proposed action will not jeopardize any
federally-listed threatened or endangered species or their habitats. Rat eradication is
consistent with the Service responsibility to manage and conserve migratory bird
populations under the Migratory Bird Treaty Act, the National Bald Eagle Management
Guidelines, conventions and other applicable laws including the ANILCA which gives
legal purposes of the Alaska Maritime NWR to conserve marine birds, other migratory
birds, marine mammals and the habitats on which they rely; and to protect and preserve
the wilderness character of the area. The proposed action will not establish a precedent
for any future action with significant effects. I agree with this conclusion, and therefore
find that an EIS does not need to be prepared.

- Wrwo Wollm> ve Qoo8

Thomas O. Melius Date
Regional Director



FINDING OF NO SIGNIFICANT IMPACT

Environmental Assessment for Restoring Wildlife Habitat on Rat Island, Alaska
Maritime National Wildlife Refuge, Aleutian Islands Unit

SUMMARY

The U.S. Fish and Wildlife Service (Service) proposes to restore the natural biodiversity
of Rat Island within the Alaska Maritime National Wildlife Refuge (NWR) by
eradicating invasive Norway rats. The Environmental Assessment (EA) attached to this
document analyzes the consequences of the following two alternatives: 1) no action; and
2) the proposed action - eradication of non-native Norway rats by aerial broadcast of bait
containing the rodenticide brodifacoum. We chose the proposed action over the no action
alternative. This Finding of No Significant Impact (FONSI) documents our conclusion
that the proposed action will not have any significant impacts on the quality of the human
environment.

ACTION PURPOSE & NEED

Two key purposes of Alaska Maritime NWR are: (1) to conserve marine birds (i.e.,
seabirds), other migratory birds, marine mammals and the habitats on which they rely;
and (2) to secure an enduring resource of wilderness, to protect and preserve the
wilderness character of the area as part of the National Wilderness Preservation System,
and to administer the area for the use and enjoyment of the American people in a way
that will leave it unimpaired for future use and enjoyment as wilderness. The purpose of
the proposed action, consistent with the purposes of the Refuge, is to restore native
habitat for wildlife, especially seabirds, and wilderness character of Rat Island by
permanently removing introduced rats. The detrimental impacts introduced rats have on
island ecosystems is discussed in the EA.

SUMMARY OF PROPOSED ACTION

Rat Island is a 6,861 acre uninhabited island located 1,300 miles southwest of Anchorage,
Alaska in the central Aleutian Islands. The proposed action will use two island-based
helicopters to spread pelletized bait containing brodifacoum. Aerial application of the
rodenticide during fall was chosen because it is a feasible and cost-effective method of
eliminating the ongoing environmental damage caused by rats. This method was selected
after consideration of other eradication techniques because it is the most successful and
tested method of accomplishing the proposed action on an island as large as Rat Island.
Some non-target mortality of birds is expected but the loss of individuals will have no
significant population-level effects. Timing of bait application, application rate, and bait
characteristics are all designed to minimize effects on non-target species. Most rats will
die underground, reducing secondary poisoning to predators and scavengers.
Furthermore, any carcasses found during and immediately after baiting will be removed.
Bait stations may be selectively used as well. Although no bait will be deliberately
broadcast into the marine environment, some bait drift into both marine and fresh water is


Reference Cited

Bailey, E. P. 1993. Introduction of foxes to Alaskan Islands---history, effects on
avifauna, and eradication. USDI Fish and Wildlife Service, Resource Publication 193,
Washington, D.C.

Byrd, G.V., C.F. Zeillemaker, and J.L. Trapp. 1994. Removal of introduced foxes: A
case study in restoration of native birds. Trans. 59th No. Am. Wildl. and Nat. Resour.
Conf. 59:317-321.

Croll, D.A., J.L. Maron, J.A. Estes, E.M. Danner, and G.V. Byrd. 2005. Introduced
predators transform subarctic islands from grassland to tundra. Science 307:1959-1961.

Ebbert, S.E. and G.V. Byrd 2002. Eradications of invasive species to restore natural
biological diversity on Alaska Maritime National Wildlife Refuge. pp. 102-109 in C.
Veitch and M. Clout, eds. Turning the Tide: The eradication of Invasive Species. IUCN
SSC Invasive Species Specialist Group. IUCN. Gland, Switzerland.

Howald, G., C.J. Donlan, J.-P. Galvan, J.C. Russell, J. Parkes, A. Samaniego, Y. Wang,
D. Veitch, P. Genovesi, M. Pascal, A. Saunders, and B. Tershy. 2007. Invasive rodent
eradications on islands. Conservation Biology 21(5): 1258-1268,.

Witmer, G. W., F. Boyd, and Z. Hillis-Star. 2007. The successful eradication of
introduced roof rats (Rattus rattus) on Buck Island using diphacinone, followed by
resource recovery and an irruption of house mice (Mus musculus). Wildlife Research.
34: 108-115.


possible. Nevertheless, during a previous study on other Aleutian Islands where pellets
were broadcast to mimic the application proposed at Rat Island, analysis of water samples
revealed no detectable brodifacoum. The project is designed to reduce marine mammal
disturbance yet maximize efficacy of eradication. The safety of personnel involved in the
proposed action will be emphasized through careful planning and training. Rodenticide
will only be used according to label directions and consistent with all other pertinent
regulations. All permits for use of rodenticide will be obtained prior to application.

Pending final approval of permits and pesticide regulation compliance, Rat Island
eradication operations will begin in fall 2008 when rodent productivity and food
resources are declining, after breeding seasons have ended for birds and marine
mammals, and before severe winter conditions persist.

EFFECTS AND FINDINGS

There will likely be some limited mortality of individual birds (e.g., common ravens) that
directly ingest bait during the proposed action. However, non-target mortality of
individuals on Rat Island will not affect populations of any bird species as a whole within
the Rat Islands group of the Aleutians. Indeed, we expect there will be long-term
benefits to bird populations on Rat Island as a result of rat eradication, which is one of the
primary purposes of the proposed action.

Analysis of potential effects of the proposed action on marine mammals indicates no risk
of significant effects to those using Rat Island and surrounding waters, namely Steller sea
lions, harbor seals, and northern sea otters. Actions will be taken to avoid concentrations
of northern sea otters, thereby reducing concern for this species. Helicopter operations
will likely cause temporary disturbances to Steller sea lions and harbor seals, but over-
flights and associated activities are not expected to injure or decrease their fitness.

The human environment on Rat Island (including other biological resources, water
resources, historic and cultural resources, or human uses and values associated with the
island) will not be significantly affected. Except for government researchers, humans
very rarely visit the island, and there is little, or no, subsistence use of resources from the
island or surrounding waters. Additionally, the EA determined that the wilderness
character of Rat Island will not be permanently compromised; instead wilderness
character is being restored as a result of rat removal.

The proposed action is designed to restore the biodiversity of Rat Island by removing all
Norway rats on the island, but Norway rats are common elsewhere in the world. The
proposed action will have no effect on abundance of the species elsewhere.

PUBLIC INVOLVEMENT
The EA was prepared and released for a 30-day public comment period on the Alaska

Maritime NWR web site beginning December 12, 2007, through January 11, 2008. Over
800 notices of availability were mailed directly to agencies, organizations, and


individuals. More than 150 notices were sent by e-mail. A press release was distributed
to news outlets in Alaska and the nation. Refuge staff gave three radio interviews about
the project. The notice of availability, a list of frequently asked questions, and a fact
sheet about the project were mailed to communities in the Aleutian Island geographic
area including: City of Adak, villages of Atka and Nikolski, and Unalaska.

During the public comment period, we received 37 responses: 22 from individuals, 6
from conservation organizations, 2 from trade associations, 2 from Native organizations,
2 from governmental agencies, 1 from a professional scientific organization, 1 from a
non-profit research institute, and 1 from an academic institution.

Of the 32 comments that expressed an opinion, 30 were in support of the proposed action,
and 2 comments were opposed. Not all comments clearly stated support or opposition to
the proposed action (e.g., some offered suggestions of alternative products or techniques).
Based on the balance of public comments received, the effects on the quality of the
human environment are not highly controversial.

The following section addresses the subjects of the material issues raised during the
public comment period.

1. Choice of Rodenticide

One comment pertained to our choice of rodenticide. Two rodenticides used in rat
eradications in the U.S., brodifacoum and diphacinone, were initially considered for use
on Rat Island. We selected brodifacoum as the rodenticide to use in the proposed action
primarily because of its proven success in the vast majority of eradication efforts
worldwide (Howald et. al. 2007), and thus its ability to achieve the purpose of the
proposed action. While diphacinone has been used successfully 5 times in island rat
eradications, brodifacoum has been used successfully 200 times (Howald et. al. 2007).
Based on the best available scientifice information available to the Service at this time,
there have been no confirmed successful eradications with diphacinone that have been
carried out by hand or aerial broadcast. We recognize that testing of diphacinone and its
potential for use as an island eradication tool by broadcast is ongoing elsewhere.
However, because of the relatively large size of Rat Island (one of the larger islands
targeted for rat eradication in the world), which necessitates an aerial broadcast, and the
difficulty of carrying out an eradication operation on an island as remote as Rat Island,
which necessitates an approach that can maximize the likelihood of successfully
eradicating rats on the first attempt, we chose to use brodifacoum rather than diphacinone
for the proposed action. Additional rationale for our selection of rodenticide is outlined
in the EA.

2. Non-target Issues
We recognize that brodifacoum has greater non-target hazard than diphacinone.

Nevertheless, because of increased likelihood of success in removing all rats at Rat Island
with brodifacoum, the short-term non-target impacts are deemed non-significant and