UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON D.C., 20460 

MEMORANDUM 

SUBJECT: 

TO: 

FROM: 

THROUGH: 

Summary 

Office of Chemical Safety 

and Pollution Prevention 

DP Barcode: 411406 

PCCodes:016601,016001,129083,076103,076104,077501 

Date: 06/28/2013 

Revision to the environmental fate and ecological risk assessment for 

carbon dioxide and for carbon, sawdust, sodium nitrate, potassium 

nitrate and sulfur containing cartridges 

Eric Miederhoff, Chemical Review Manager 

Patricia Parrot, Branch Chief 

Risk Management and Implementation Branch 3 

Pesticide Re-evaluation Division (7508P) 

Carissa Cyran, Chemical Review Manager 

Neil Anderson, Branch Chief 

Risk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

Jose Gayoso, Chemical Review Manager 

Kevin Costello, Branch Chief 

Risk Management and Implementation Branch 2 

Pesticide Re-evaluation Division (7508P) j .(_ (2;1-" 

Joseph DeCant, Ecologist ~ f. 

Environmental Risk Branch 5 (J - I/ 

Environmental Fate and Effects Division (7507P) 

Mah Shamim, Branch Chief 

Environmental 

Environmental 

Risk 

Fate and 

Branch 

Effects 

5 

Division (7507P) 

~ 

Information in this revised risk assessment presents an update to the risk assessment for carbon 

dioxide and for carbon, sawdust, sodium nitrate, potassium nitrate and sulfur containing 

cartridges, hereafter referred to as gas cartridges, (PC Code 016601, 016001, 129083, 076104, 

076103 and 077501; Case Nos. 0031,4019 and 4052; DP Barcode D375973) that was completed 

on March 30, 2010. This revised assessment also provides an updated direct effects list that is 

presented in Table 3 and includes 56 species ofterrestrial vertebrates that inhabit burrows and/or 

dens to which a "Likely to Adversely Affect" (LAA) determination applies. The Environmental 

1 
2

Fate and Effects Division (EFED) revised the previous direct effects list contained in the

addendum to the risk assessment dated July 16, 2012, by removing six additional listed species 

(including the Louisiana black bear, Florida panther, jaguar, ocelot, frosted flatwoods 

salamander, and reticulated flatwoods salamander) from the direct effects list based on updated 

information regarding their life histories and the expected lack of exposure to gas cartridges. In 

addition, this revised assessment also presents an overview of previous consultations between 

state and federal agencies and the FWS related to the use of gas cartridges. Finally, a number of 

mitigation options are available in order to eliminate exposure to many of the listed species

remaining on the updated direct effects list provided in Table 3. The July 16, 2012, addendum 

included a number of potential mitigation options including modifications to the label to limit 

application of the gas cartridges to control only those species identified as target pests on the 

current labels, prohibiting use on the Channel Islands along the coast of California and the 

Hawaiian Islands, prohibiting use on specific federal lands where a species occurs, and 

prohibiting use in areas where a species is known to occur based upon available spatial 

information from the U.S. Fish and Wildlife Service (FWS). This revised assessment reiterates 

these potential mitigation options and also adds an option to restrict the timing of use in certain 

areas. If these modifications and prohibitions are added to the labels and/or bulletins, five listed 

species would remain on the direct effects list for formal consultation with the FWS. 

Background

On March 30, 2010, EFED completed its environmental fate and ecological risk assessment for 

carbon dioxide and for carbon, sawdust, sodium nitrate, potassium nitrate and sulfur containing 

cartridges (PC Code 016601, 016001, 129083, 076104, 076103 and 077501; Case Nos. 0031, 

4019 and 4052; DP Barcode D375973). In this assessment, EFED identified potential direct 

effects for listed terrestrial mammals, terrestrial birds (including amphibians and reptiles for 

which birds serve as a surrogate) and terrestrial invertebrates, based on 100% mortality assumed 

at the application site from asphyxiation. These effects result in a LAA determination for those 

species directly affected. There are also LAA determinations for listed terrestrial mammals, 

birds, reptiles, amphibians, invertebrates, and plants for indirect effects from the use of the 

cartridges. The LAA determination for indirect effects to listed plants is expected to be limited 

to those listed plants that rely on affected species for seed dispersal and pollination. The EPA

also made a No Effect determination for aquatic species, given the expected lack of exposure to 

non-target taxa. The number of species on the direct effects list identified in this 2010 risk 

assessment totaled 64 species.

Since the initial 2010 risk assessment, the direct effects list has undergone multiple refinements. 

These refinements are reflected in Table 1 and further described in more detail in the following 

paragraphs. Following the completion of this assessment, EFED updated the list of species that 

are expected to be both directly and indirectly impacted by the current registration of gas 

cartridges in a memo dated November 16, 2010 (D384643) in which 58 species remained on the 

direct effects list. Adjustments to the original list of directly and indirectly affected species were 

made following several pathways of refinement. First, the two sizes of the gas cartridges1

were 

 

1 Large gas cartridge = 1 and 9/16 inches (outside diameter of tube) x 12 inches long; small gas cartridge = 1 and 

9/16 inches (outside diameter of tube x 6 inches long).
3

evaluated relative to den/burrow openings of various species to determine if the size of the gas 

cartridge could be used to remove a species from the direct effects list. Second, FWS Region 42

provided information on listed species within the geographic range of Region 4. Based on this

information provided by FWS Region 4, six species including the Anastasia Island beach mouse

(Peromyscus polionotus phasma), Choctawhatchee beach mouse (Peromyscus polionotus 

allophrys), Key Largo cotton mouse (Peromyscus gossypinus), southeastern beach mouse

(Peromyscus polionotus niveiventris), lower keys marsh rabbit (Sylvilagus palustris hefneri), and 

the red hills salamander (Phaeognathus hubrichti) were removed thereby bringing the total 

number of species on the direct effects list to 58. The Key Largo cotton mouse and the lower 

keys marsh rabbit were removed because they do not inhabit belowground burrows. The 

remaining species were removed due to the low likelihood of exposure as it would be unlikely 

for the gas cartridges to be used in their burrows due to burrow size (red hills salamander) or 

burrow location (beach mice). In addition, a number of listed plants with seeds that are wind, 

water, or self-dispersed were also removed from the indirect effects list.

Table 1. Timeline of the initial March 30, 2010, risk assessment and the following revisions

of the direct effects list. The final column reflects the major changes to the direct effects 

list since the previous version.

Assessment

Description (DP 

Barcode)

Date

Number of 

Species on 

Direct Effects 

List

Major Conclusions/Revisions

Environmental Fate 

and Ecological Risk 

assessment (375973)

March 30, 2010 64

LAA for listed terrestrial mammals, birds, and 

invertebrates that inhabit burrows/dens 

belowground due to direct effects. LAA for listed 

terrestrial mammals, reptiles, amphibians, birds, 

invertebrates, and plants due to indirect effects. No 

Effect for listed aquatic species.

Input for Mitigation 

Option (384643)

November 16, 

2010 58

Six species were removed from the original direct 

effects list including the red hills salamander, lower 

keys marsh rabbit, Key Largo cotton mouse, 

Anastasia Island beach mouse, Choctawhatchee 

beach mouse, and the southeastern beach mouse.

Addendum to the

Environmental Fate 

and Ecological Risk 

Assessment 

(403061)

July 16, 2012 62

The Agency concluded No Effect for terrestrial 

invertebrates and therefore removed them from the 

direct effects list (total of 16 species). Four 

additional species were removed including Preble’s 

Meadow Jumping Mouse, Western Burrowing Owl, 

Lake Erie Water Snake, and the New Mexican 

Ridge-nosed Rattlesnake. The Anastasia Island 

beach mouse, Choctawhatchee beach mouse, 

southeastern beach mouse were added back to the 

direct effects list. In addition, 19 species were added 

to the direct effects list including the Mississippi 

gopher frog, Florida panther, Alabama beach 

mouse, Carolina northern flying squirrel, gray wolf, 

Key Largo woodrat, Pacific pocket mouse, Perdido 

Key beach mouse, Hawaiian dark rumped petrel, 

San Joaquin kit fox, Florida salt marsh vole, St. 

 

2 FWS Region 4 memo to the Pesticide Re-evaluation Division (PRD), July 26, 2010. 
4

Andrew beach mouse, bog turtle, copperbelly 

watersnake, San Francisco garter snake, desert 

slender salamander, frosted flatwoods salamander, 

Houston toad, and the reticulated flatwoods 

salamander. The California tiger salamander was 

split into its three distinct population segments on 

the direct effects list. Plants that were on the indirect 

effects list but are known to not require vertebrate 

pollinators or seed dispersers were removed from 

the list.

Revised 

Environmental Fate 

and Ecological Risk 

Assessment 

(411406)

June 28, 2013 56

Six additional species were removed from the direct 

effects list including the ocelot, Florida panther, 

Louisiana black bear, frosted flatwoods salamander, 

reticulated flatwoods salamander, and the jaguar.

Using the species list contained in the November 16, 2010, memo (D384643), further 

refinements were made based on an updated search of listed species on the FWS website3

. 

Specifically, listed terrestrial species that may inhabit burrows or dens at some point in their lifecycle were identified, and the life history of each species as well as the size of the associated 

burrow or den relative to the two sizes of gas cartridges were considered. For example, if a listed 

species’ burrow or den was too small to accommodate the gas cartridge, it was assumed that gas 

cartridges would not be used and the associated listed species was removed from the direct 

effects list. During this second refinement, three species of beach mice, including the Anastasia 

Island beach mouse, the Choctawhatchee beach mouse, and the southeastern beach mouse, were 

re-evaluated with additional information. These species were returned to the direct effects list in 

an addendum to the original risk assessment dated July 16, 2012 (D403061) because the habitat 

of the three beach mice may co-occur with the habitat of the house mouse. Although the house 

mouse is not specifically listed as a pest species on the gas cartridge labels, use of gas cartridges 

to control the house mouse is not prohibited. According to the information from FWS Region 

44

, gas cartridges may be used to control the house mouse and mistakenly be used in beach 

mouse burrows. These additions to the direct effects list and the associated mitigation options 

are summarized in the addendum to the risk assessment (D403061).

The July 16, 2012 (D403061) addendum also addressed terrestrial invertebrates. In the case of

burrowing invertebrates, they have a life history that does not result in exposure to the gas 

cartridges as their burrows are not large enough to allow for gas cartridge use. For example, the 

larvae of tiger beetles live in burrows; however, the sizes of the burrows are too small for a gas 

cartridge. The American burying beetle also does not make burrows of sufficient size to allow 

for the use of gas cartridges, and the carcasses that are buried for reproduction do not represent a 

“burrow” or “den” in which gas cartridges could potentially be used. Cave dwelling spiders that 

were on the original direct effects list from the March 30, 2010 (D375973), risk assessment are 

not expected to be either exposed to or affected by gas cartridges because the cave entrance(s) is

too large and/or not feasible to seal as required by the gas cartridge labels. Furthermore, it is 

expected that a cave would be too large for the gas cartridge to effectively remove all of the 

oxygen regardless of the entrance size. Thus, there are currently no listed species within the 

 

3 http://www.fws.gov/endangered/species/us-species.html 4 Ibid FWS memo July 26, 2010.
5

invertebrate taxa that would have a life history resulting in exposure and direct effects. 

Consequently, the LAA determination as identified in the March 30, 2010 (D375973), risk 

assessment no longer holds for terrestrial invertebrates and a No Effect determination was found 

for terrestrial invertebrate taxa. 

This current revised assessment provides additional refinements to the list of species that may be 

directly affected as well as an additional mitigation recommendation beyond those listed in the 

July 16, 2012 (D403061) addendum. This revised assessment also reiterates mitigation options

to eliminate potential exposure in order to come to a No Effect determination for certain species 

on the direct effects list. The focus of this revised assessment is on refinements to listed 

terrestrial animals that may be directly impacted by gas cartridges. It is acknowledged that a 

number of listed species may be indirectly affected, including those species also on the direct 

effects list. These species include mammals, birds, reptiles, amphibians, invertebrates, as well as 

plants. The use of gas cartridges may indirectly affect listed plant species that rely on pollinators

and animals involved in seed dispersal. EFED anticipates that mitigation options that reduce the 

number of species on the direct effects list would also reduce the number of species that would 

be indirectly affected by the use of gas cartridges.

Regarding No Effect determinations, 26 species that were on the original direct effects list from

the March 30, 2010 (D375973) risk assessment, including invertebrates, have been removed 

from the direct effects list throughout the various iterations of this risk assessment. The list of 

these species and the justification for their removal from the direct effects list can be found in

Table 2. This list includes three species that were removed in the November 16, 2010, memo

(D384643), as a result of comments from FWS Region 4 (red hills salamander, lower keys marsh 

rabbit, and Key Largo cotton mouse). The Louisiana black bear, ocelot, and jaguar are no longer 

on the direct effects list in this revised assessment due to consideration of additional information 

on life history traits and the types of dens that these species use that preclude exposure to the gas 

cartridges. Three other species including the Florida panther, frosted flatwoods salamander, and 

reticulated flatwoods salamander were included in the July 16, 2012 (D403061), addendum, but 

removed from the direct effects list in this revised assessment due to additional habitat 

considerations. The Florida panther does not make use of underground dens, and the listed 

salamanders use burrows in wetland areas that would preclude the use of gas cartridges. 

Table 2. Species that were on the original direct effects list in the March 30, 2010, risk 

assessment but removed per the current revised assessment. The table presents the 

justification for the removal of each species.

No. Species

Common Name

Scientific 

Namea Statusa States Justification for Removal

Source(s)

1

Beetle, 

American 

Burying

Nicrophorus 

americanus E

AR,GA, 

KS, KY, 

MA, MO, 

OH, OK, 

RI, SD, TX

Does not use or 

inhabit burrows of 

other animals; Does 

not create burrows 

large enough to 

accommodate gas 

cartridges

NatureServe 2011; 

FWS Region 4 

comments related to 

the lack of direct 

effects to this speciesb

2 Beetle, Ohlone 

Tiger

Cicindela 

ohlone E CA

Does not use or 

inhabit burrows of 

other animals; Does 

Recovery Plan for 

Insect and Plant Taxa 

from the Santa Cruz 
6

No. Species

Common Name

Scientific 

Namea Statusa States Justification for Removal

Source(s)

not create burrows 

large enough to 

accommodate gas 

cartridges

Mountains in 

California, September 

28, 1998c

3 Florida Panther Puma (=Felis) 

concolor coryi E FL

Creates dens in 

dense understory 

vegetation; Does not 

use or create 

belowground dens 

with entrances that 

can be sealed; rather, 

it creates 

aboveground dens

Florida Panther 

Recovery Plan, 3rd

Revision, November 

1, 2008d

; NatureServe 

2011

4

Frosted 

Flatwoods 

Salamander

Ambystoma 

cingulatum T FL, GA, 

SC

Salamander uses 

crayfish burrows in 

upland flatwood 

sites that are 

unlikely to be use 

sites for gas 

cartridges

FWS comments: 

email dated August 8, 

2012

5 Harvestman, Bee 

Creek Cave Texella reddelli E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Endangered Karst 

Invertebrates 

Recovery Plan Travis 

and Williamson 

Counties, TX, 1994e

6 Harvestman, 

Bone Cave Texella reyesi E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Endangered Karst

Invertebrates 

Recovery Plan Travis 

and Williamson 

Counties, TX, 1994f

7

Harvestman, 

Robber Baron 

Cave

Texella 

cokendolpheri E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011g

8 Jaguar Panthera onca E AZ, NM

Dens are located in 

dense brush or in 

cavesh

; Does not use 

or create 

belowground dens 

with entrances that 

can be sealed

NatureServe 2011

9 Key Largo 

Cotton Mouse

Peromyscus 

gossypinus E FL Does not use or 

create burrows

FWS Region 4 

comments related to 

the lack of direct 

effects to this speciesb

10 Lake Erie Water 

Snake

Nerodia sipedon 

insularum N/A OH Delisted due to recovery

11 Louisiana Black 

Bear

Ursus 

americanus 

luteolus

T LA, MS, 

TX

In the range of the 

LA black bear, dens 

are likely either 

aboveground or in 

FWS Region 4 

comments related to 

the lack of direct 

effects to this 
7

No. Species

Common Name

Scientific 

Namea Statusa States Justification for Removal

Source(s)

trees; NLAA 

determination from 

previous 

consultation with gas 

cartridges

speciesb; FWS 

biological opinion 

regarding Wildlife 

Services coyote 

biological control 

program dated 

October 9, 2001

12 Lower Keys 

Marsh Rabbit

Sylvilagus 

palustris hefneri E FL Does not use or 

create burrows

FWS Region 4 

comments related to 

the lack of direct 

effects to this speciesb

13 Meshweaver, 

Braken Bat Cave Cicurina venii E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011i

14

New Mexican 

Ridge-nosed 

Rattlesnake

Crotalus 

willardi 

obscurus

T AZ, NM

Available 

information does not 

indicate the use of 

burrows

New Mexico 

Ridgenosed 

Rattlesnake Recovery 

Plan, 1985j

; 

NatureServe 2011

15 No Common 

Name Rhadine exilis E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011k

16 No Common 

Name

Rhadine 

infernalis E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011l

17 Ocelot

Leopardus 

(=Felis) 

pardalis

E AZ, TX

Creates dens in thick 

brush or dense 

bunchgrass 

surrounded by brush; 

Does not use or 

create belowground 

dens with entrances 

that can be sealed; 

rather, it creates 

aboveground dens

Ocelot Recovery Plan 

Draft First Revision, 

August 22, 1990m

18

Preble’s 

Meadow 

Jumping Mouse

Zapus 

hudsonius 

preblei

E CO, WY

Size of the 

hibernation burrow 

does not 

accommodate the 

size of either type of 

gas cartridge; day 

nests are 

aboveground

FWS Wyoming 

Ecological Services; 

Draft Environmental 

Assessment Proposal 

of Critical Habitat for 

Preble’s Meadow 

Jumping Mouse dated 

December 19, 2002n

19 Pseudoscorpion, 

Tooth Cave

Tartarocreagris 

texana

E TX Cave dwelling 

species, karst caves 

would not be a use 

Endangered Karst 

Invertebrates 

Recovery Plan Travis 
8

No. Species

Common Name

Scientific 

Namea Statusa States Justification for Removal

Source(s)

site for gas 

cartridges

and Williamson 

Counties, TX, 1994o

20 Red Hills 

Salamander

Phaeognathus 

hubrichti T AL

Digs burrows that 

are difficult to 

access and unlikely 

to be use site for 

cartridges

FWS region 4 

comments related to 

the lack of direct 

effects to this speciesb

21

Reticulated 

Flatwoods 

Salamander

Ambystoma 

bishopi E FL, GA

Salamander uses 

crayfish burrows in 

upland flatwood

sites that are 

unlikely to be use 

sites for gas 

cartridges

FWS comments: 

email dated August 8, 

2012

22

Spider, 

Government 

Canyon Cave

Neoleptoneta 

microps E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011p

23 Spider, Kauai 

Cave Wolf

Adelocosa 

anops

E HI

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Recovery Plan for the 

Kauai Cave 

Arthropods, April 28, 

2006q

24 Spider, Madla's

Cave Cicurina madla E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011r

25 Spider, Robber 

Baron Cave

Cicurina 

baronia E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011s

26 Spider, SpruceFir Moss

Microhexura 

montivaga E NC, TN Does not use or 

inhabit burrows/dens

Recovery Plan for the 

Spruce-fir Moss 

Spider September 11, 

1998t

27 Spider, Tooth 

Cave

Leptoneta 

myopica E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Endangered Karst 

Invertebrates 

Recovery Plan Travis 

and Williamson 

Counties, TX, 1994u

28 Spider, Vesper 

Cave

Cicurina 

vespera

E TX

Cave dwelling 

species, karst caves 

would not be a use 

site for gas 

cartridges

Bexar County Karst 

Invertebrates 

Recovery Plan, 

August 2011v

29 Western 

Burrowing Owl

Athene 

cunicularia 

hypugea

N/A

AZ, CA, 

CO, IA, 

ID, KS, 

Not listed
9

No. Species

Common Name

Scientific 

Namea Statusa States Justification for Removal

Source(s)

LA, MN, 

MT, ND, 

NE, NV, 

OK, OR, 

SD, TX, 

WA, WY a E = Endangered, T = Threatened, N/A = Not applicable 

b FWS Region 4 memo to the Pesticide Re-evaluation Division (PRD), July 26, 2010 c http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=I0OW d http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A008

e http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J008

f http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J009

g http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J016

h Similar to the rationale for the cave dwelling invertebrate species, the jaguar may make its den in caves but the 

entrances are considered too large to seal or the volume of the cave too large for the gas cartridge to be efficacious i

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J01D

j

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=C01S

k http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=I0RF l

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=I0P1

m http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A084 n http://www.fws.gov/wyominges/Pages/Species/Species_Listed/Prebles.html

o http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J00A

p http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J018

q http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J000

r

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J019

s http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J01A

t

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J014

u http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J00B

v http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=J01B

Listed species of various taxa, 16 in total, have been added to the direct effects list throughout 

the various iterations of this risk assessment due to additional information on their life histories

and their use of burrows or dens. These 16 species were not on the original list from the March 

30, 2010, risk assessment (D375973). In the case of the California tiger salamander, the species

is separated in this assessment into its three distinct population segments, whereas in the original 

direct effects list it was listed simply at the species level. The 16 additional species, most of 

which were added to the previous addendum, are incorporated into the direct effects list in this 

revised aassessment. The species include:

• Mississippi gopher frog

• Alabama beach mouse

• Carolina northern flying squirrel

• Gray wolf

• Key Largo woodrat

• Pacific pocket mouse

• Perdido Key beach mouse

• Hawaiian dark rumped petrel

• San Joaquin kit fox

• Florida salt marsh vole

• St. Andrew beach mouse

• Bog turtle

• Copperbelly watersnake

• San Francisco garter snake

• Desert slender salamander

• Houston toad 
10

With the inclusion of these additional species and distinct population segments following the 

review of the direct effects list, the final direct effects list per this revised addendum includes 56

species, which are provided in Table 3. Each of the species in Table 3 represents a listed 

species that could be directly affected by the use of gas cartridges and for which a LAA 

determination applies. 

Other classifications of species were also explored for potential inclusion on the direct effects 

list. Candidate species were not included in Table 3 because they do not receive protections 

under the Endangered Species Act. EFED also searched the list of the proposed species; 

however, there are no terrestrial burrowing species currently proposed for listing.

The 56 listed species on the direct effects list shown in Table 3 are those species that are likely 

to be adversely affected from the direct effects of gas cartridges based on currently registered 

labels. Note that Table 3 includes a column that specifies whether the species would be affected 

by the large cartridge, the small cartridge, or both. It is assumed that the small gas cartridge 

would not be used and/or effective in large dens to control large predators based on the label 

directions. Consequently, the red wolf and gray wolf would be subject to direct effects only 

from use of the large cartridge. A No Effect determination was therefore concluded for small 

gas cartridges to the red wolf and the gray wolf. The smaller species on the direct effects list 

may be present in larger abandoned dens at the time of application and therefore may be affected 

by large gas cartridge use if they are used in the abandoned dens. While smaller species are not 

likely to cohabit with large predators on which the large cartridge would be used when the dens 

are being actively used, there is the potential for mistaking an active den of the target species 

with a non-target species (e.g., coyote vs. San Joaquin kit fox) or mistaking an inactive den for

an active den. 
11

Table 3. Listed non-target species that are subject to an LAA determination based on direct effects. 

No. Species Common 

Name

Scientific Name No. of

Counties

County (State)a Size of Gas 

Cartridgeb

GIS 

Shapefilec

1 Alabama Beach 

Mouse

Peromyscus 

polionotus 

ammobates

1 Baldwin (AL) Small/Large Yes

2 Alameda 

Whipsnake

Masticophis 

lateralis 

euryxanthus

4 Alameda, Contra Costa, San Joaquin, Santa Clara (CA) Small/Large Yes

3 Amargosa Vole Microtus 

californicus 

scirpensis

1 Inyo (CA) Small/Large Yes

4 Anastasia Island 

Beach Mouse

Peromyscus 

polionotus phasma

1 St. John’s (FL) Small/Large Yes

5 Arroyo 

Southwestern Toad

Bufo californicus 

(=microscaphus)

8 Los Angeles, Monterey, Orange, Riverside, San Bernardino, 

San Diego, Santa Barbara, Ventura (CA)

Small/Large Yes

6 Black-footed Ferret, 

Endangered

Mustela nigripes 141 Apache, Coconino, Navajo, Yavapai (AZ)

County-level range not defined (CO)

Logan (KS)

Big Horn, Blaine, Carbon, Carter, Chouteau, Custer, Fergus, 

Garfield, Golden Valley, Hill, Jefferson, Lewis and Clark, 

Liberty, McCone, Musselshell, Petroleum, Phillips, Powder 

River, Prairie, Rosebud, Stillwater, Sweet Grass, Toole, 

Treasure, Valley, Wheatland, Yellowstone (MT)

Adams, Antelope, Arthur, Banner, Blaine, Boone, Box Butte, 

Boyd, Brown, Buffalo, Chase, Cherry, Cheyenne, Clay, 

Colfax, Custer, Dawes, Deuel, Dundy, Filmore, Franklin, 

Frontier, Furnas, Garden, Garfield, Gosper, Grant, Greeley, 

Hall, Hamilton, Harlan, Hayes, Hitchcock, Holt, Hooker, 

Howard, Jefferson, Kearney, Keith, Keya Paha, Kimball, 

Knox, Lincoln, Logan, Loup, Madison, McPherson, Merrick, 

Morrill, Nance, Nuckrolls, Perkins, Phelps, Pierce, Platte, Polk, 

Red Willow, Rock, Saline, Scotts Bluff, Seward, Sheridan, 

Sherman, Sioux, Thayer, Thomas, Valley, Webster, Wheeler, 

York (NE)

Small/Large Partial 

(Incomplete 

Dataset)
12

Colfax (NM)

Adams, Billings, Bowman, Dunn, Golden Valley, Grant, 

Hettinger, McKenzie, Mercer, Morton, Oliver, Sioux, Slope, 

Stark (ND)

Corson, Custer, Dewey, Gregory, Jackson, Lyman, Mellette, 

Pennington, Shannon, Todd, Tripp, Ziebach (SD)

County-level range not defined (UT)

Big Horn, Carbon, Fremont, Hot Springs, Lincoln, Natrona, 

Park, Sublette, Sweetwater, Uinta, Washakie (WY)

Counties in addition to the above which contain only 

experimental populations:

Adams, Alamosa, Arapahoe, Archuleta, Baca, Broomfield, 

Conejos, Costilla, Delta, Douglas, Kiowa, Kit Carson, La Plata, 

Larimer, Las Animas, Moffat, Montezuma, Montrose, Morgan, 

Otero, Prowers, Pueblo, Rio Blanco, Saguache, San Miguel, 

Washington, Weld (CO)

County-level range not defined (SD)

Uintah (UT)

Albany (WY)

7 Blunt-nosed 

Leopard Lizard

Gambelia silus 5 Monterey, San Benito, San Luis Obispo, Santa Barbara, 

Ventura (CA)

Small/Large Yes

8 Bog Turtle Clemmys 

muhlenbergii

49 Fairfield, Litchfield (CT)

New Castle (DE)

Baltimore, Carroll, Cecil, Harford (MD)

Burlington, Gloucester, Hunterdon, Mercer, Monmouth, 

Morris, Ocean, Salem, Somerset, Sussex, Union, Warren (NJ)

Cayuga, Columbia, Dutchess, Genesee, Onondaga, Orange, 

Small/Large Yes
13

Oswego, Putnam, Rensselaer, Rockland, Seneca, Sullivan, 

Ulster, Wayne, Westchester (NY)

Adams, Berks, Bucks, Carbon, Chester, Cumberland, 

Delaware, Lancaster, Lebanon, Lehigh, Monroe, Montgomery, 

Northampton, Schuylkill, York (PA)

9 Buena Vista Lake 

Ornate Shrew

Sorex ornatus 

relictus

2 Kern, San Luis Obispo, Additional portions of the range within 

CA still need to be refined (CA)

Small/Large Yes

10 California Redlegged FrogRana draytonii 30 Alameda, Butte, Contra Costa, El Dorado, Fresno, Kern, Los 

Angeles, Marin, Mariposa, Mendocino, Merced, Monterey, 

Napa, San Benito, San Bernardino, San Diego, San Joaquin, 

San Luis Obispo, San Mateo, Santa Barbara, Santa Clara, Santa 

Cruz, Siskiyou, Solano, Sonoma, Stanislaus, Tehama, Trinity, 

Tuolumne, Ventura (CA)

Small/Large Yes

11 California Tiger 

Salamander (Santa 

Barbara DPS)

Ambystoma 

californiense

1 Santa Barbara (CA) Small/Large Yes

12 California Tiger 

Salamander (Central 

Valley DPS)

Ambystoma 

californiense

5 Monterey, San Benito, San Luis Obispo, Santa Cruz, Sonoma 

(CA)

Small/Large Yes

13 California Tiger 

Salamander 

(Sonoma DPS)

Ambystoma 

californiense

31 Alameda, Amador, Butte, Calaveras, Colusa, Contra Costa, El 

Dorado, Fresno, Glenn, Kern, Kings, Madera, Marin, 

Mariposa, Merced, Napa, Placer, Sacramento, San Joaquin, 

San Luis Obispo, San Mateo, Santa Clara, Santa Cruz, Solano, 

Sonoma, Stanislaus, Sutter, Tulare, Tuolumne, Yolo, Yuba, 

Additional portions of the range within this state still need to 

be refined (CA)

Small/Large Yes

14 Carolina Northern 

Flying Squirrel

Glaucomys 

sabrinus coloratus

20 Ashe, Avery, Buncombe, Caldwell, Graham, Haywood, 

Henderson, Jackson, McDowell, Mitchell, Swain, 

Transylvania, Watauga, Yancey (NC)

Carter, Monroe, Sevier, Unicoi (TN)

Grayson, Smyth (VA)

Small/Large Yes

15 Choctawhatchee 

Beach Mouse

Peromyscus 

polionotus 

allophrys

3 Bay, Okaloosa, Walton (FL) Small/Large Yes

16 Coachella Valley Uma inornata 2 Riverside, San Bernardino (CA) Small/Large Yes
14

Fringe-toed Lizard

17 Copperbelly Water 

Snake

Nerodia 

erythrogaster 

neglecta

12 Kosciusko, St. Joseph, Steuben (IN)

Branch, Calhoun, Cass, Eaton, Hillsdale, St. Joseph (MI)

Defiance, Hardin, Williams (OH)

Small/Large Yes

18 Desert Slender 

Salamander

Batrachoseps 

aridus

1 Riverside (CA) Small/Large Yes

19 Desert Tortoise Gopherus agassizii 13 Mohave (AZ)

Imperial, Inyo, Kern, Los Angeles, Riverside, San Bernardino, 

San Diego (CA)

Clark, Esmeralda, Lincoln, Nye (NV)

Washington (UT)

Small/Large Yes

20 Eastern Indigo 

Snake

Drymarchon 

corais couperi

98 Appling, Atkinson, Bacon, Berrien, Bryan, Bulloch, Camden, 

Charlton, Clinch, Coffee, Echols, Emanuel, Evans, Irwin, Jeff 

Davis, Lanier, Liberty, Long, Lowndes, McIntosh, Randolph, 

Tattnall, Telfair, Wayne, Wheeler (GA)

Alachua, Bay, Brevard, Broward, Calhoun, Charlotte, Citrus, 

Clay, Collier, Columbia, DeSoto, Dixie, Duval, Escambia, 

Franklin, Gadsden, Gilchrist, Glades, Gulf, Hamilton, Hardee, 

Hendry, Hernando, Highlands, Hillsborough, Holmes, Indian 

River, Jackson, Jefferson, Lafayette, Lake, Lee, Leon, Levy, 

Liberty, Madison, Manatee, Marion, Martin, Miami-Dade, 

Monroe, Nassau, Okaloosa, Okeechobee, Orange, Osceola, 

Palm Beach, Pasco, Pinellas, Polk, Putnam, Santa Rosa, 

Sarasota, Seminole, St. Johns, St. Lucie, Sumter, Suwannee, 

Taylor, Union, Volusia, Wakulla, Walton, Washington (FL)

Baldwin, Coffee, Covington, Dale, Escambia, Geneva, 

Houston, Mobile, Washington (AL)

Small/Large Partial 

(Incomplete 

Dataset)

21 Fresno Kangaroo 

Rat

Dipodomys 

nitratoides exilis

1 Fresno (CA) Small/Large Yes

22 Giant Garter Snake Thamnophis gigas 31 Alameda, Amador, Butte, Calaveras, Colusa, Contra Costa, El 

Dorado, Fresno, Glenn, Kern, Kings, Lake, Madera, Mariposa, 

Merced, Napa, Nevada, Placer, Sacramento, San Joaquin, San 

Luis Obispo, Santa Clara, Santa Cruz, Solano, Stanislaus, 

Sutter, Tehama, Tulare, Tuolumne, Yolo, Yuba, Additional 

portions of the range within this state still need to be refined 

(CA)

Small/Large Yes

23 Giant Kangaroo Rat Dipodomys ingens 4 Monterey, San Benito, San Luis Obispo, Ventura (CA) Small/Large Yes
15

24 Gopher Tortoise Gopherus 

polyphemus

25 Choctaw, Mobile, Washington (AL)

St. Tammany, Tangipahoa, Washington (LA)

Clarke, Covington, Forrest, George, Greene, Hancock, 

Harrison, Jackson, Jasper, Jefferson Davis, Jones, Lamar, 

Marion, Pearl River, Perry, Smith, Stone, Walthall, Wayne 

(MS)

Small/Large Yes

25 Gray Wolf Canis lupus 221 County level range not defined (CO)

Alger, Baraga, Cheboygan, Chippewa, Delta, Dickinson, 

Emmet, Gogebic, Houghton, Iron, Keweenaw, Luce, 

Mackinac, Marquette, Menominee, Ontonagon, Presque Isle, 

Schoolcraft (MI)

Adams, Antelope, Arthur, Banner, Blaine, Boone, Box Butte, 

Boyd, Brown, Buffalo, Burt, Butler, Cass, Cedar, Chase, 

Cherry, Cheyenne, Clay, Colfax, Cuming, Custer, Dakota, 

Dawes, Dawson, Deuel, Dixon, Dodge, Douglas, Dundy, 

Fillmore, Franklin, Frontier, Furnas, Gage, Garden, Garfield, 

Gosper, Grant, Greeley, Hall, Hamilton, Harlan, Hayes, 

Hitchcock, Holt, Hooker, Howard, Jefferson, Johnson, 

Kearney, Keith, Keya Paha, Kimball, Knox, Lancaster, 

Lincoln, Logan, Loup, Madison, McPherson, Merrick, Morrill, 

Nance, Nemaha, Nuckolls, Otoe, Pawnee, Perkins, Phelps, 

Pierce, Platte, Polk, Red Willow, Richardson, Rock, Saline, 

Sarpy, Saunders, Scotts Bluff, Seward, Sheridan, Sherman, 

Sioux, Stanton, Thayer, Thomas, Thurston, Valley, 

Washington, Wayne, Webster, Wheeler, York (NE)

Elko (NV)

Catron, Grant, Hidalgo, Sierra (NM)

Adams, Barnes, Benson, Billings, Bottineau, Bowman, Burke, 

Burleigh, Cass, Cavalier, Dickey, Divide, Dunn, Eddy, 

Emmons, Foster, Golden Valley, Grand Forks, Grant, Griggs, 

Hettinger, Kidder, LaMoure, Logan, McHenry, McIntosh, 

McKenzie, McLean, Mercer, Morton, Mountrail, Nelson, 

Large No
16

Oliver, Pembina, Pierce, Ramsey, Ransom, Renville, Richland, 

Rolette, Sargent, Sheridan, Sioux, Slope, Stark, Steele, 

Stutsman, Towner, Traill, Walsh, Ward, Wells, Williams (ND)

County-level range not defined (OR)

County-level range not defined (SD)

County-level range not defined (UT)

Chelan, Kittitas, Klickitat, Okanogan, Snohomish, Whatcom, 

Yakima (WA)

Adams, Ashland, Barron, Bayfield, Burnett, Chippewa, Clark, 

Douglas, Eau Claire, Florence, Forest, Iron, Jackson, Juneau, 

Langlade, Lincoln, Marathon, Marinette, Marquette, 

Menominee, Monroe, Oconto, Oneida, Polk, Portage, Price, 

Rusk, Sawyer, Shawano, Taylor, Vilas, Washburn, Waupaca, 

Wood (WI)

Counties in addition to the above which contain only 

experimental populations:

Big Horn, Fremont, Hot Springs, Lincoln, Park, Sublette, Teton 

(WY)

Apache, Gila, Greenlee, Navajo (AZ)

County-level range not defined (NM)

County-level range not defined (TX)

26 Houston Toad Bufo houstonensis 9 Austin, Bastrop, Burleson, Colorado, Lavaca, Lee, Leon, 

Milam, Robertson (TX)

Small/Large Yes

27 Hualapai Mexican 

Vole

Microtus 

mexicanus 

hualpaiensis

1 Mohave (AZ) Small/Large Yes

28 Island Night Lizard Xantusia 

riversiana

3 Los Angeles, Santa Barbara, Ventura (CA) Small/Large Yes

29 Key Largo Woodrat Neotoma floridana 

smalli

1 Monroe (FL) Small/Large Yes

30 Mississippi Gopher Rana capito sevosa 2 Harrison, Jackson (MS) Small/Large Yes
17

Frog

31 Morro Bay 

Kangaroo Rat

Dipodomys 

heermanni 

morroensis

1 San Luis Obispo (CA) Small/Large Yes

32 Mount Graham Red 

Squirrel

Tamiasciurus 

hudsonicus 

grahamensis

1 Graham (AZ) Small/Large Yes

33 Northern Idaho 

Ground Squirrel

Spermophilus 

brunneus brunneus

3 Adams, Valley, Washington (ID) Small/Large Yes

34 Pacific Pocket 

Mouse

Perognathus 

longimembris 

pacificus

3 Los Angeles, Orange, San Diego (CA) Small/Large Yes

35 Perdido Key Beach 

Mouse

Peromyscus 

polionotus 

trissyllepsis

2 Baldwin (AL)

Escambia (FL)

Small/Large Yes

36 Petrel, Hawaiian 

dark-rumped

Pterodroma 

phaeopygia 

sandwichensis

3 Hawaii, Kauai, Maui Small/Large No

37 Point Arena 

Mountain Beaver

Aplodontia rufa 

nigra

1 Mendocino (CA) Small/Large Yes

38 Pygmy Rabbit Brachylagus 

idahoensis

3 Benton, Douglas, Grant, Additional portions of the range 

within WA still need to be refined (WA)

Small/Large Yes

39 Red Wolf Canus rufus 4 County-level range not defined - FL, NC, SC

Counties in addition to the above which contain only 

experimental populations:

Beaufort, Dare, Hyde, Tyrrell (NC)

County-level range not defined (TN)

Large No

40 San Bernardino 

Merriams Kangaroo 

Rat

Dipodomys 

merriami

4 Los Angeles, Orange, Riverside, San Bernardino (CA) Small/Large Yes

41 San Francisco 

Garter Snake

Thamnophis 

sirtalis tetrataenia

1 Santa Cruz (CA) Small/Large Yes

42 San Joaquin Kit Fox Vulpes macrotis 

mutica

21 Alameda, Calaveras, Contra Costa, Fresno, Kern, Kings, 

Madera, Mariposa, Merced, Monterey, Sacramento, San 

Benito, San Joaquin, San Luis Obispo, Santa Barbara, Santa 

Clara, Santa Cruz, Solano, Stanislaus, Tulare, Tuolumne (CA)

Small/Large Yes
18

43 San Miguel Island 

Fox

Urocyon littoralis 

littoralis

1 Santa Barbara (CA) Small/Large Yes

44 Santa Catalina 

Island Fox

Urocyon littoralis 

catalinae

1 Los Angeles (CA) Small/Large Yes

45 Santa Cruz Island 

Fox

Urocyon littoralis 

santacruzae

1 Santa Barbara (CA) Small/Large Yes

46 Santa Cruz Longtoed SalamanderAmbystoma 

macrodactylum 

croceum

2 Monterey, Santa Cruz (CA) Small/Large Yes

47 Santa Rosa Island 

Fox

Urocyon littoralis 

santarosae

1 Santa Barbara (CA) Small/Large Yes

48 Shearwater, 

Newell's 

Townsend's

Puffinus 

auricularis newelli

4 Hawaii, Honolulu, Kauai (HI)

Manu’a (American Samoa)

Small/Large No

49 Sonora Tiger 

Salamander

Ambystoma 

tigrinum stebbinsi

2 Cochise, Santa Cruz (AZ) Small/Large Yes

50 Southeastern Beach 

Mouse

Peromyscus 

polionotus 

niveiventris

7 Brevard, Broward, Indian River, Martin, Palm Beach, St. 

Lucie, Volusia (FL)

Small/Large Yes

51 St. Andrew Beach 

Mouse

Microtus 

pennsylvanicus 

dukecampbelli

2 Bay, Gulf (FL) Small/Large Yes

52 Stephens Kangaroo 

Rat

Dipodomys 

stephensi

4 Orange, Riverside, San Bernardino, San Diego (CA) Small/Large Yes

53 Tipton Kangaroo 

Rat

Dipodomys 

nitratoides 

nitratoides

5 Fresno, Kern, Kings, San Luis Obispo, Tulare, Additional 

portions of the range within CA still need to be refined (CA)

Small/Large Yes

54 Utah Prairie Dog Cynomys 

parvidens

7 Beaver, Garfield, Iron, Kane, Piute, Sevier, Wayne (UT) Small/Large Yes

55 Vole, Florida Salt 

Marsh

Microtus 

pennsylvanicus 

dukecampbelli

1 Levy (FL) Small/Large No

56 Wyoming Toad Bufo baxteri

(=hemiophrys)

1 Albany (WY) Small/Large Yes

a List of counties obtained from the U.S. Fish and Wildlife Service endangered species website: http://www.fws.gov/endangered/species/us-species.html. The 

counties include populations that are threatened, endangered, and experimental. When the counties only contain experimental populations, these counties are 

listed separately.

b Specifies the size of gas cartridge which would result in an LAA determination for the specific species. c “Yes” denotes EFED has received from the FWS a GIS shapefile containing comprehensive spatial data on the area where a given species occurs that may be 

incorporated into Bulletins Live (referenced in the following sections).
19

Previous Consultations Between Federal and State Agencies and the Fish 

and Wildlife Service

1. USDA Animal and Plant Health Inspection Service-Wildlife Services Use of the 

Small Gas Cartridge/Large Gas Cartridge in the Range of a Species

The current gas cartridge labels (both large and small) already mitigate to some extent for 

endangered species concerns as a result of previous consultations with the FWS. The March 30, 

2010, risk assessment (D375973) discussed additional supporting information that was provided 

from a 1993 Biological Opinion (BO) indicating jeopardy to certain terrestrial mammals and 

reptiles with specific Reasonable and Prudent Alternatives (RPAs) for each of these species. The 

BO also listed Reasonable and Prudent Measures (RPMs) for those species with a no jeopardy 

determination. As a result of these RPAs and RPMs, each of the gas cartridge product labels 

includes specific label language requiring a qualified applicator when the products are applied in 

the range of the following federally listed species:

• Fresno kangaroo rat

• Giant kangaroo rat

• Stephen’s kangaroo rat

• Tipton kangaroo rat

• Point Arena mountain beaver

• San Joaquin kit fox

• Desert Tortoise

For other species, gas cartridge use already has specific geographic use restrictions in the ranges 

of certain endangered species including:

• Hualapai Mexican vole

• Morro Bay kangaroo rat

• Utah prairie dog

• Coachella Valley fringe-toed lizard

• Island night lizard

• Blunt-nosed leopard lizard

• San Francisco garter snake 

• Eastern Indigo snake

• Gopher tortoise

• Black-footed ferret

USDA Animal and Plant Health Inspection Service (APHIS) Wildlife Services (WS) engaged in 

an ESA section 7 consultation with the FWS in 1992 to prepare for its programmatic 

Environmental Impact Statement (EIS) in 1994. Various regional ESA section 7 consultations 

for the USDA/APHIS gas cartridges include those in California, Illinois, Nevada, and Ohio. 

These previous consultations produced mitigation measures, as listed in Table 4, which were 
20

either proposed by APHIS-WS with FWS concurrence or derived from RPMs and RPAs 

developed by the FWS.

Table 4. Mitigations from previous biological opinions or concurrence letters from the Fish 

and Wildlife Service related to specific local or statewide uses.

Biological Opinion or 

Concurrence Letter Species

Mitigation to Reduce 

Exposure/Rationale for No 

Exposure

1993 FWS Biological Opiniona

Black-footed ferret Prohibition of use within range 

of species

Tipton kangaroo rat Use limited to qualified 

applicator

Fresno kangaroo rat Use limited to qualified 

applicator

Giant kangaroo rat Use limited to qualified 

applicator

Hualapai Mexican vole Prohibition of use within range 

of species

Morro Bay kangaroo rat Prohibition of use within range 

of species

Point Arena Mountain Beaver Use limited to qualified 

applicator

San Joaquin kit fox Use limited to qualified 

applicator

Stephen’s kangaroo rat Use limited to qualified 

applicator

Blunt-nosed leopard lizard Prohibition of use within range 

of species from October 1 –

April 15

San Francisco garter snake Species will not coexist with 

coyote in active dens

Eastern Indigo Snake Prohibition of use within range 

of species

Gopher tortoise Prohibition of use within range 

of species

Utah prairie doge Prohibition of use within range 

of species

Desert Tortoise Use limited to qualified 

applicator

Coachella Valley fringe-toed 

lizard

Prohibition of use within range 

of species

Island night lizard Prohibition of use within range 

of species

2007 FWS Concurrence Letter 

for Large Gas Cartridge Use in 

Californiab

Point Arena Mountain Beaver Use limited to qualified 

applicator

San Bernardino Merriam’s 

kangaroo rat

Use limited to qualified 

applicator

San Joaquin kit fox Use limited to qualified 

applicator
21

Tipton kangaroo rat Use limited to qualified 

applicator

Stephen’s kangaroo rat Use limited to qualified 

applicator

Buena Vista Lake shrew Use sites do not overlap with 

range of species

Fresno kangaroo rat Use limited to qualified 

applicator

Giant kangaroo rat Use limited to qualified 

applicator

Morro Bay kangaroo rat Prohibition of use within range 

of species

Pacific pocket mouse Little opportunity for exposure

Arroyo southwestern toad Species will not coexist with 

coyote in active densc

California red-legged frog Species will not coexist with 

coyote in active dens

California tiger salamander Species will not coexist with 

coyote in active densc

Desert slender salamander Species will not coexist with 

coyote in active densc

Santa Cruz long-toed salamander Species will not coexist with 

coyote in active densc

Alameda whipsnake Little opportunity for exposure

Blunt-nosed leopard lizard Prohibition of use within range 

of species from October 1 –

April 15

Coachella Valley fringe-toed 

lizard

Prohibition of use within range 

of species

Giant garter snake Species will not coexist with 

coyote in active densc

Island night lizard Prohibition of use within range 

of species

San Francisco garter snake Species will not coexist with 

coyote in active densc, Use 

limited to qualified applicator 

between April 1 and October 

31

Amargosa vole Little opportunity for exposure

2003 Biological Opinion for 

Large/Small Gas Cartridge in 

Nevadad

Desert tortoise Use limited to qualified 

applicator

2012 Informal Consultation 

Letter for Gas Cartridge use in 

Ohioe

Copperbelly watersnake Prohibition of use within range 

of species

a U.S. Fish and Wildlife Service. 1993. Final Biological Opinion in Response to U. S. Environmental Protection 

Agency’s September 30, 1988, Request for Consultation on Potassium Nitrate and Sodium Nitrate Cartridges. U. 

S. Department of Interior, Fish and Wildlife Service (EHC/BFA?9-89-1). b U.S. Fish and Wildlife Service. 2007. Concurrence letter regarding amended biological assessment for APHISWS activities to protect livestock, property, human health and safety, and natural resources in the State of 
22

California. U.S. Department of Interior, Fish and Wildlife Service. c Observance standard will apply to these species denoting the visual confirmation of active use of dens by 

coyote.

d U.S. Fish and Wildlife Service. 2003. Informal consultation/biological opinion for addressing effects on all

federally listed or proposed threatened and endangered species in Nevada as a result of the Animal and Plant 

Health and Inspection Service-Wildlife Service’s implementation of proposed wildlife damage management 

activities under the Nevada animal damage control plan. U.S. Department of Interior, Fish and Wildlife Service 

(1-5-03-F-400). e U.S. Fish and Wildlife Service. 2012. Endangered Species Act Section 7 informal consultation response to Ohio 

mammal Environmental Analysis. U.S. Department of Interior, Fish and Wildlife Service (03E15000-2012-I1052).

When the gas cartridges are used specifically by APHIS-WS personnel, previous consultations 

included notable requirements in the form of mitigations proposed by the USDA-WS in addition 

to mitigations based on RPAs or RPMs from relevant biological assessments. For example, the 

mitigations in the consultation that resulted in no jeopardy for the desert tortoise in Nevada 

required the following:

1. The large/small cartridges are used in burrows/dens only when they are in active use by 

the target animal.

2. Areas proposed for application of sodium and potassium nitrate (predator fumigants) in 

desert tortoise occupied habitat, including vehicle access routes, shall be inspected for 

desert tortoises by a qualified representative of APHIS-WS who has been trained to 

distinguish target from non-target species dens as per EPA label restrictions for desert 

tortoises. All burrows capable of providing shelter for tortoises shall be inspected with a 

fiber-optic scope if necessary, to determine occupancy of each burrow by desert tortoises. 

Fumigants shall not be applied to burrows if inspections indicate that the burrows are 

occupied by tortoises.

3. A qualified desert tortoise biologist will be responsible for informing all APHIS-WS 

personnel administering [Wildlife Damage Management] programs in desert tortoise 

habitat about the desert tortoise. This will include information on the life history of the 

desert tortoise, legal protection for desert tortoises, penalties for violations of Federal and 

State laws, general tortoise activity patterns, reporting requirements, measures to protect 

tortoises, and personal measures employees can take to promote the conservation of 

desert tortoises. The definition of “take” will also be explained.

In accordance with Procedures for Endangered Species Act Compliance for the Mojave 

Desert Tortoise (USFWS 1992a), a biologist should possess a bachelor’s or graduate 

degree in biology, ecology, wildlife biology, herpetology, or related fields. The biologist 

must have demonstrated prior field experience using accepted resource agency techniques 

to survey for desert tortoises. Field experience may mean a minimum of 60 days field 

experience searching for desert tortoises and tortoise sign. In addition, the biologist 

should have the ability to recognize and accurately identify all types of desert tortoise 

sign. USFWS does not endorse any individual or company with respect to their abilities 

to conduct satisfactory surveys.
23

4. Fumigants shall be used only by qualified individuals and per EPA label instruction. 

Such persons shall be limited to qualified wildlife biologists, or to agents of county 

agricultural commission offices, university extension offices, or representatives of State 

or Federal wildlife agencies.

5. APHIS-WS shall submit a report to USFWS...following the year in which [Wildlife 

Damage Management] activities occurred within desert tortoise habitat. The report shall 

include: (1) number of tortoises taken and circumstances, e.g., crushed by project vehicle 

or asphyxiated by fumigants, (2) listing of all tortoises encountered or observed in project 

areas including exact locations and dates, (3) number of NADCP activities abandoned 

due to the presence of desert tortoise, and (4) recommendations for enhancing the 

effectiveness of terms and conditions.

The consultation in California led the FWS to concur with either a NLAA or No Effect determination 

for the listed species based on proposed mitigations consistent with the 1993 FWS BO. For example, 

the biological assessment from APHIS-WS dated July 8, 2004, and amended February 7, 2007, for 

the Point Arena mountain beaver states, “The use of gas cartridges within the occupied habitats of the 

Point Arena mountain beaver is limited, by its label, to qualified individuals who have been trained 

to distinguish dens and burrows of target species from those of non-target species. The cartridges 

will be used only in active coyote dens.” In other instances, the mitigation simply prohibits use in the 

range of the specific species (e.g., island night lizard). These requirements are also the same RPA, in 

the case of the Point Arena mountain beaver, and RPM, in the case of the island night lizard, as those

identified in the 1993 FWS BO.

Based on these biological assessments, resulting biological opinions, and concurrence by the FWS 

with the conclusions of APHIS-WS, several essential features of protective action for uses by 

APHIS-WS are apparent (Table 5). In general, the protective actions listed in Table 5 lead to a No 

Effect determination when use is prohibited in the range of a protected species or an NLAA call 

when use will occur in the range of a protected species. EPA intends to revisit the results of these 

previous consultations with the FWS to ensure that these protective actions continue to protect 

federally listed species that are likely to be affected by gas cartridge use.

Table 5. Protective actions based on previous consultations between APHIS-WS and FWS, 

and the resulting determinations for the species on the direct effects list due to large and 

small gas cartridge use.

Protective Action by APHIS-WS

Will Use in the 

Range of the Species 

on the Direct Effects 

List Occur?

EFED Determination 

for Threatened and 

Endangered Species on 

the Direct Effects List

Prohibition of use in the range of a species No No Effect

a. Positive identification (observance 

standard) of the “active use” of a burrow 

or den by the target species

b. Confirmation that the listed species of 

concern is not present in the target 

burrow/den

c. Use of the gas cartridge by a “qualified” 

Yes NLAA
24

individual as stated above from previous 

consultations who is either a wildlife 

biologist specializing in the specific

species or is guided by the wildlife 

biologist

2. 1996 Consultation Between California Department of Pesticide Regulation (CDPR)

and Fish and Wildlife Service

In 1996, the state of California requested approval from the FWS for Pesticide Bulletins related 

to the use of gas cartridges. The request was specifically for the Service’s concurrence that these 

bulletins adequately protect affected threatened and endangered species and can be substituted 

for the RPM’s and RPA’s that were described in the FWS 1993 biological opinion (see Table 4

for information on the 1993 biological opinion). A total of 14 species were addressed in the 

CDPR bulletins that are also on the direct effects list. These bulletins addressed the species in 

Table 6 and provided the corresponding use limitations.

Table 6. Limitations on gas cartridge use according to the CDPR 1996 pesticide bulletins 

for various federally listed species in California.

Species Limitations Code*

California red-legged frog 5, 30

Alameda whipsnake

Blunt-nosed leopard lizard

Giant garter snake

5, 31

Desert tortoise 5, 32

Amargosa vole

Fresno kangaroo rat

Giant kangaroo rat

Morro Bay kangaroo rat

Point Arena mountain beaver

Stephen’s kangaroo rat

Tipton kangaroo rat

5

Pacific pocket mouse

San Francisco garter snake (San Mateo and Santa 

Cruz counties only)

5, 33

*5: Use shall be supervised by a person (wildlife biologist, county agricultural commissioner, university extension 

advisor, state or federal official or others) who is trained to distinguish dens and burrows of target species from 

those of non-target species. The person responsible for supervision shall be aware of the conditions at the site of 

application and be available to direct and control the manner in which applications are made (per Section 6406 of 

Title 3, California Code of Regulations). Contact your county agricultural commissioner for information on 

training.

30: Use is prohibited within 500 feet of water courses at any time, EXCEPT: a) in cultivated areas

31: Use is prohibited from October 1 through April 30, EXCEPT: a) in cultivated areas, or b) on the water side of 

water supply channels

32: Use is prohibited from July 1 through February 28, EXCEPT: a) in cultivated areas, or b) on the water side of 

water supply channels

33: Use is prohibited EXCEPT with a prior site evaluation by the county agricultural commissioner in cooperation 

with the Department of Fish and Game and the U.S. Fish and Wildlife Service.
25

Based on the above protective actions, the FWS provided CDPR with a letter of concurrence stating 

that the gas cartridge bulletins “adequately protect federally listed species during the [gas cartridge] 

uses and that they are consistent with the conclusions of the March 1993 Vertebrate Control 

biological opinion”. However, this conclusion only applies to those species addressed in the 1993 

biological opinion. Consequently, four species including the California red-legged frog, Alameda 

whipsnake, giant garter snake, and the pacific pocket mouse are not covered by this letter of 

concurrence from the FWS. It is also important to note that whereas the USDA APHIS-WS 

consultation applied to only APHIS-WS personnel, the consultation between CDPR and FWS 

applied to all users. Similar to the previous consultation between APHIS-WS and FWS, EPA also 

intends to revisit the CDPR consultation with the FWS to continue to ensure adequate protections 

remain in place for federally listed species that are likely to be affected by gas cartridge use.

Mitigation Options 

There are a number of mitigation options that are available to eliminate exposure to potentially 

impacted listed species. The following section presents the results of the currently available

mitigation options and the impact those mitigation options would have on the list of species 

provided in Table 3. 

1. Label Target Species

Gas cartridges are currently registered for the use of controlling rodents and other burrowing pest 

species. At present, five labels address small mammal burrows and specifically mention the 

following target species: moles, pocket gophers, woodchucks, rats and Norway rats, ground 

squirrels, skunks, yellow-bellied marmots, and prairie dogs. In addition, one label for a larger 

gas cartridge size can be used in dens and is labeled to control coyotes, red foxes, and striped 

skunks. Although the labels specifically mention the aforementioned mammals, the labels for 

the small and large gas cartridges registered by the USDA do not limit use to only these target 

species. Due to distinctive habitat conditions where burrows are made, seven species would 

benefit from clarifying the label language to limit the use of the gas cartridges to only those 

species currently listed on the labels. These label changes would ensure that no exposure occurs 

for these seven species, and consequently a No Effect determination could be made for the 

following the listed species on the direct effects list. Further description of these species is 

provided below:

1. Bog turtle

2. St. Andrew beach mouse

3. Perdido Key beach mouse

4. Alabama beach mouse

5. Southeastern beach mouse

6. Anastasia Island beach mouse

7. Choctawhatchee beach mouse

The bog turtle, Clemmys (Glyptemys) muhlenbergii, is a species that inhabits slow, shallow, 

muck-bottomed rivulets of sphagnum bog, calcareous fens, marshy/sedge-tussock meadows, 

spring seeps, wet cow pastures, and shrub swamps. This species will burrow into soft substrates 

along waterways and use muskrat burrows, which are made in the sides of steep banks of ponds, 
26

lakes, or other waterways. With the above labeling restriction, the gas cartridges could not be 

used to control muskrats. Therefore, the bog turtle would not be exposed to the use of gas 

cartridges in muskrat burrows, and a No Effect determination would be made for the bog turtle.

There are six species of beach mouse (St. Andrew beach mouse, Perdido Key beach mouse, 

Alabama beach mouse, Southeastern beach mouse, Anastasia Island beach mouse, and 

Choctawhatchee beach mouse) that could also be affected by the label restriction on target 

species. As mentioned before, three of these beach mice were previously removed from the 

direct effects list. However, their addition back to the direct effects list is a function of the 

potential overlap of habitat with the house mouse. Each of these species inhabits the frontal, 

secondary, and tertiary coastal dune zone. Their burrows are not shared with any target species. 

However, the house mouse may make burrows alongside the burrows of the beach mice in 

developed areas. Where habitat overlaps, there could be exposure to the beach mice. Given that 

none of the labeled target species have habitat that overlaps with the beach mice in these dune 

systems, if the labels limited use to only the target pest species, then the gas cartridge could not 

be used on the house mouse. Consequently, the specification of use only on the labeled target 

species would remove the potential for exposure to each of the species of beach mouse and lead 

to a No Effect determination. 

2. Geographic Restrictions

a. Federally Managed Lands

The species on the direct effects list occur in a variety of locations, some on private land and 

others on public federally managed land or both. There are six species, as shown below, that are 

located solely on federal land. The Pesticide Re-evaluation Division has contacted the federal 

land managers for those species which occur solely on federal land to determine the extent of gas 

cartridge use and the extent to which the land managers intend to use the gas cartridges in the 

future. These listed species and their associated federal lands include the following:

1. Mount Graham red squirrel

a. Coronado National Forest – Forest Service

2. Carolina northern flying squirrel

a. Cherokee National Forest – Forest Service

b. Jefferson National Forest – Forest Service

c. Nantahala National Forest – Forest Service

d. Pisgah National Forest – Forest Service

e. Middle Prong Wilderness – Forest Service

f. Great Smoky Mountains National Park – National Park Service

g. Blue Ridge Parkway – National Park Service

3. Desert slender salamander 

a. Santa Rosa Wilderness – Bureau of Land Management

4. Santa Rosa Island fox

a. Channel Island National Park – National Park Service

5. San Miguel Island fox

a. Channel Island National Park – National Park Service

6. Santa Cruz Island fox
27

a. Channel Island National Park – National Park Service

The Mount Graham red squirrel, Carolina northern flying squirrel, desert slender salamander, 

and the Santa Rosa, San Miguel, and Santa Cruz Island foxes are all located entirely on federally 

managed lands. Based on the input provided by these federal agencies5, gas cartridges are not 

currently used in the geographic areas inhabited by the above species. If gas cartridges were 

prohibited specifically in the areas where these species occur within the respective federally 

managed lands, the EPA would come to a No Effect determination due to a lack of exposure. 

The areas of prohibited use would be reflected in a modification to the current gas cartridge 

labels via reference to Bulletins Live6, which is an online tool that provides geospatial 

information on areas where pesticide use limitations are in place in order to minimize risk to 

listed species. By reference, Bulletins are an enforceable extension of the pesticide label. Given 

the current lack of gas cartridge use on these lands, these restrictions are not likely to pose a 

burden to the respective federal agency. If gas cartridges are proposed for use by these

management agencies in the future, the specific federal agency responsible for the management 

of that federal land would also be responsible for initiating consultation with the FWS according 

to Section 7 of the Endangered Species Act. Bulletins Live would then be amended as 

appropriate according to the results of the consultation.

b. Channel Islands and Hawaiian Islands

The Channel Islands are a series of eight islands off the coast of California. The following five 

species on the direct effects list are located solely on the Channel Islands:

1. Island Night lizard

2. Santa Rosa Island fox

3. San Miguel Island fox

4. Santa Catalina Island fox

5. Santa Cruz Island fox 

The island foxes inhabit the islands for which they are named. The Island Night lizard inhabits 

three islands including San Nicholas, San Clemente, and Santa Barbara Island. Therefore, these 

species combined inhabit 7 out of the 8 Channel Islands. As previously stated, some of the 

Channel Islands are under the authority of the National Park Service (NPS). The Santa Rosa, 

San Miguel, and Santa Cruz Island foxes are located solely on NPS land and are not areas of 

current gas cartridge use7 at the present time. As previously mentioned, the Santa Rosa, San 

Miguel, and Santa Cruz islands could be added to Bulletins Live to specifically prohibit gas 

cartridge use on these islands and eliminate potential exposure to the respective island foxes. 

However, the Island Night lizard occurs on both private and federally managed land, and the 

Santa Catalina Island fox only inhabits privately owned land within the Channel Islands. The 

 

5 NPS email to PRD regarding the Channel Islands, May 21, 2012. 

NPS email to PRD regarding the Carolina northern flying squirrel, May 16, 2012.

FS email to PRD regarding the Mt. Graham red squirrel, November 29, 2011. 

FS email to PRD regarding the Carolina northern flying squirrel, May 24, 2012.

BLM email to PRD regarding the desert slender salamander: June 19, 2012.

6 http://www.epa.gov/oppfead1/endanger/bulletins.htm 7 Ibid NPS email May 21, 2012. 
28

privately owned Channel Islands that are inhabited by these two listed species may also be added 

to Bulletins Live in order to prohibit use in these geographic areas. If gas cartridge use is 

prohibited from the Channel Islands via Bulletins Live, there would be no exposure to the 

Channel Islands listed species, and the EPA would come to a No Effect determination for these 

species. 

The Hawaiian Islands are also a potential focus for mitigation. If gas cartridge use were 

prohibited on the Hawaiian Islands, the two burrowing bird species would also have no potential 

exposure to gas cartridges. These birds include the Hawaiian dark-rumped petrel and the 

Newell’s Townsend’s shearwater, both of which occur in several areas of the Hawaiian Islands. 

The Hawaiian Islands would then be added to Bulletins Live and the EPA would come to a No 

Effect determination for these species as well. In addition to a No Effect determination for these 

two bird species, a No Effect determination would also apply to all of the Hawaiian species on 

the indirect effects list. 

c. Restriction on Timing of Use

The majority of species on the direct effects list in Table 3 could be adversely affected at any 

time of the year by the use of gas cartridges in their range. However, the copperbelly watersnake 

is an exception due to its life history. According to information provided by the FWS8

, the 

copperbelly watersnake hibernates only in crayfish burrows during the winter months. These 

hibernacula are unlikely to be use sites for gas cartridges due to both the size of crayfish burrows 

as well as the location of crayfish burrows in wet or saturated soils. The period of hibernation 

for the copperbelly watersnake extends from October 15 to April 15. During other times of year, 

the snake will inhabit other burrows, including those in more upland areas, which may be use 

sites for the gas cartridges. Consequently, the snake may be adversely affected from April 16 to 

October 14. If gas cartridge use is allowed only during the period from October 15 to April 15 in 

the range of the copperbelly watersnake, then exposure to this species would not occur and a No 

Effect determination would be concluded for the copperbelly watersnake.

d. Additional Restrictions on Use Sites

Most species are located on a combination of public and private lands. In order to characterize 

the spatial distribution of the species occurrences, EFED has collected Geographic Information 

System (GIS) spatial data (i.e., shapefiles) from the listed species’ experts within the FWS field 

offices for as many species as possible, depending on the availability of the data. Datasets are 

available for some of the species previously discussed. These species include:

1. Alabama beach mouse

2. Anastasia Island beach mouse

3. Carolina northern flying squirrel

4. Choctawhatchee beach mouse

5. Desert slender salamander

6. Island Night lizard

 

8 FWS emails August 23, 2012 and September 4, 2012
29

7. Mount Graham red squirrel

8. Perdido Key beach mouse

9. San Miguel Island fox

10. Santa Catalina Island fox

11. Santa Cruz Island fox

12. Santa Rosa Island fox

13. St. Andrew beach mouse

Full spatial datasets are also available for the following species:

1. Alameda whipsnake

2. Amargosa vole

3. Arroyo southwestern toad

4. Blunt-nosed leopard lizard

5. Bog turtle

6. Buena Vista Lake ornate shrew

7. California red-legged frog

8. California tiger salamander (Central 

Valley DPS)

9. California tiger salamander (Santa 

Barbara DPS)

10. California tiger salamander (Sonoma 

DPS)

11. Coachella Valley fringe-toed lizard

12. Copperbelly water snake

13. Desert tortoise

14. Fresno kangaroo rat

15. Giant garter snake

16. Giant kangaroo rat

17. Gopher tortoise

18. Houston Toad

19. Hualapai Mexican vole

20. Key Largo woodrat

21. Mississippi gopher frog

22. Morro Bay kangaroo rat

23. Northern Idaho ground squirrel

24. Pacific pocket mouse

25. Point Arena mountain beaver

26. Pygmy rabbit

27. San Bernardino Merriam’s kangaroo 

rat

28. San Francisco garter snake

29. San Joaquin kit fox

30. Santa Cruz long-toed salamander

31. Sonora tiger salamander

32. Southeastern beach mouse

33. Stephens’ kangaroo rat

34. Tipton kangaroo rat

35. Utah prairie dog

36. Wyoming toad

The datasets for these additional species show the ranges of where these species are located. The 

ranges of these species identified by the spatial data may be added to Bulletins Live, pending 

agreement by the registrants of the gas cartridge labels, to prohibit use of the gas cartridges in 

these areas. Note that specific spatial data on ranges are unavailable for two species for which 

mitigation is available and has already been addressed in the previous sections. These species 

include the two bird species (Hawaiian dark-rumped petrel and the Newell’s Townsend’s 

shearwater) from Hawaii. In summary, exposure would be eliminated with geographic 

restrictions and a No Effect determination would apply to any additional species beyond those 

that may already have been addressed through the previously mentioned mitigation options. 

Results of the Refinement of the Direct Effects List

Each of the above proposed mitigation options is intended to reduce the potential for exposure to

listed species from gas cartridges. There are a number of mitigation solutions that lead to a No 
30

Effect determination for various species. These mitigation solutions include the following:

 Limiting the potential target species for gas cartridge applications to only those listed 

explicitly on product labels.

 Prohibiting gas cartridge use in areas where listed species of concern are known to 

occur.

 Prohibiting gas cartridge use in areas where listed species of concern are known to 

occur only at times of year when the species is likely to inhabit potential cartridge use 

sites. 

If after all of the aforementioned mitigation solutions leading to No Effect determinations were 

implemented on product labels, a total of five species total would remain on the “LAA” direct 

effects list. These species include:

1. Black-footed ferret

2. Eastern indigo snake

3. Florida salt marsh vole

4. Gray wolf

5. Red wolf

These listed species either do not have spatial data provided by the FWS to indicate their range, 

or the spatial data is incomplete. Given the lack of complete spatial data for these species, it is 

not possible to implement mitigation to eliminate potential exposure from gas cartridges. For 

these species, the potential for exposure to and associated risk from gas cartridges would remain. 

If exposure to gas cartridges for any of the species listed in Table 3 is not mitigated to the point 

of a No Effect determination, EPA will consult with the FWS on the listed species which remain 

on the direct effects “LAA” list while taking into account the results of previous consultations 

between the FWS and the relevant agency (i.e., APHIS-WS or CDPR) as appropriate.