Draft Environmental Assessment 

Native Fish Restoration Project 

Redrock Canyon 

Santa Cruz County, Arizona 

U.S. Department of the Interior 

Bureau of Reclamation 

Phoenix Area Office September 2007 
TABLE OF CONTENTS 

CHAPTER 1 – PURPOSE AND NEED .................................................................................. 4 

1.1 Introduction.................................................................................................................... 4 

1.2 Background.................................................................................................................... 5

1.2.1 The Redrock Canyon Watershed ................................................................................ 5

1.2.2 Aquatic Fauna in the The Redrock Canyon Watershed and Gila River Basin ........... 8 

1.2.3 Biological Opinion for the Central Arizona Project ................................................. 10 

1.3 Purpose and Need for Action....................................................................................... 11 

1.4 Summary of Proposed Action...................................................................................... 12 

1.5 Decisions to be Made................................................................................................... 13 

1.6 Consistency with Coronado National Forest Plan ....................................................... 14 

1.7 Public Involvement ...................................................................................................... 14

CHAPTER 2 - DESCRIPTION OF THE ALTERNATIVES ................................................ 16

2.1 No Action..................................................................................................................... 16 

2.2 Proposed Action........................................................................................................... 16

2.2.1 Fish Barrier ............................................................................................................... 16 

2.2.2 Native Species Salvage............................................................................................. 19 

2.2.3 Native Fish and Frog Removal ................................................................................. 20 

2.2.4 Restoration of Native Fish and Amphibians............................................................. 23 

2.2.5 Monitoring ................................................................................................................ 25 

2.3 Alternative A – Nonnative Removal and Native Restoration without Barrier............ 25 

2.4 Mitigation for Action Alternatives............................................................................... 26

2.5 Alternatives Considered but Eliminated from Detailed Analysis................................ 28 

2.6 Comparison of Alternatives......................................................................................... 30

CHAPTER 3 – ENVIRONMENTAL CONSEQUENCES .................................................... 32 

3.1 Water Resources.......................................................................................................... 32 

3.1.1 Affected Environment........................................................................................... 32 

3.1.2 Environmental Consequences............................................................................... 36 

3.2 Biological Resources ................................................................................................... 40 

3.2.1 Affected Environment - Vegetation...................................................................... 40 

3.2.2 Environmental Consequences - Vegetation.......................................................... 41 

3.2.3 Affected Environment – Terrestrial Wildlife........................................................ 42 

3.2.4 Environmental Consequences – Terrestrial Wildlife............................................ 42 

3.2.5 Affected Environment – Fish and Aquatic Wildlife ............................................. 44 

3.2.6 Environmental Consequences - Fish and Aquatic Wildlife.................................. 49

3.2.7 Affected Environment – Federally Listed Species ............................................... 54 

3.2.8 Environmental Consequences – Federally Listed Species.................................... 57 

3.2.9 Affected Environment – Forest Service Special Status Species........................... 60 

3.2.10 Environmental Consequences – Forest Service Special Status Species............. 64 

3.3 Cultural Resources....................................................................................................... 66

3.3.1 Affected Environment........................................................................................... 66

3.3.2 Environmental Consequences............................................................................... 67 

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3.4 Socioeconomic Effects - Livestock Grazing................................................................ 68

3.4.1 Affected Environment........................................................................................... 68

3.4.2 Environmental Consequences............................................................................... 69

3.5 Recreation and Visual Quality..................................................................................... 72

3.5.1 Affected Environment........................................................................................... 72

3.5.2 Environmental Consequences............................................................................... 73

3.6 Soils and Geology........................................................................................................ 74

3.6.1 Affected Environment........................................................................................... 74

3.6.2 Environmental Consequences............................................................................... 74

3.7 Air Quality ................................................................................................................... 76 

3.7.1 Affected Environment........................................................................................... 76 

3.7.2 Environmental Consequences............................................................................... 76

CHAPTER 4 – AGENCIES AND PERSONS CONSULTED............................................... 78 

List of Preparers.................................................................................................................. 78 

Other Contributors.............................................................................................................. 78 

List of Agencies and Persons Contacted............................................................................. 78

CHAPTER 5 – RELATED ENVIRONMENTAL LAWS/DIRECTIVES............................. 81 

CHAPTER 6 – LITERATURE CITED.................................................................................. 86

APPENDIX A. Location Records for Native and Nonnative Aquatic Vertebrates in the 

Redrock Canyon Watershed..................................................................................... 101

APPENDIX B. Distribution of Native and Nonnative Fishes in the Gila River Basin ....... 109 

APPENDIX C. Fish Barrier Design..................................................................................... 115 

APPENDIX D. List of Stream Renovation Projects in the Lower Colorado River Basin .. 118 

APPENDIX E. Use of Piscicides and Neutralization Compounds...................................... 123 

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Native Fish Restoration in Redrock Canyon ii
FIGURES AND TABLES 

Figure 1. Project area map ..................................................................................................6 

Figure 2. Locations and major features in Redrock Canyon watershed .............................7 

Figure 3. Fish barrier construction site and staging area ..................................................17 

Figure 4. Stock tanks in the Redrock Canyon watershed .................................................21 

Figure 5. Downstream view of proposed fish barrier site.................................................33 

Figure 6. Post-construction sedimentation upstream from the fish barrier.......................38 

Figure 7. Longfin dace habitat in temporally intermittent flows ......................................45 

Figure 8. Gila topminnow and western mosquitofish relative abundance in 

 Redrock Canyon 1988-2005 ..........................................................................48 

Table 1. Summary of environmental consequences by alternative...................................30 

Table 2. Water conditions in Redrock Canyon stream and springs 

 (excluding stock tanks) in June 2006..............................................................35 

Table 3. Federally listed or candidate species addressed in this EA ................................54 

Table 4. Forest Service sensitive species on the Coronado National Forest ....................62 

Table 5. Management indicator species on the Coronado National Forest ......................63 

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Native Fish Restoration in Redrock Canyon iii
CHAPTER 1 -- PURPOSE AND NEED 

1.1 INTRODUCTION 

The Bureau of Reclamation (Reclamation) and the cooperating agencies listed below 

have prepared this environmental assessment (EA) to analyze the potential effects of a 

proposed aquatic ecosystem restoration project on physical, biological, and cultural 

resources. The proposed project, which would be authorized for implementation on 

National Forest System (NFS) land, would include construction of a fish barrier, removal 

of nonnative fish and frogs, and restoration of the native fish and amphibian fauna in 

Redrock Canyon, Sierra Vista Ranger District, Coronado National Forest (CNF), Santa 

Cruz County, Arizona. 

The EA was prepared in accordance with the National Environmental Policy Act 

(NEPA), Council on Environmental Quality (CEQ) regulations (40 CFR 1500-1508), 

Reclamation NEPA Handbook, and Forest Service NEPA Handbook 1909.15 

(Environment Policy and Procedures). Reclamation is the lead Federal agency and the 

U.S. Forest Service, the U.S. Fish and Wildlife Service (FWS), and the Arizona Game 

and Fish Department (AGFD) are cooperating agencies, as defined in 40 CFR 1501.6. 

This document is organized into six chapters and appendices: 

• Chapter 1 – Purpose and Need: This chapter presents information on the history 

of the proposed action/project, the purpose of and need for the action, and the lead 

agency’s proposal for achieving that purpose and need. This section also 

describes public involvement in the NEPA process. 

• Chapter 2 – Comparison of Alternatives, including the Proposed Action: This 

chapter provides a detailed description of the lead agency’s proposed action; 

cooperating agencies’ proposed actions; alternative methods for satisfying the 

stated purpose and need; and key issues that are raised by the public, project 

proponents, and other agencies. The discussion also includes specific mitigation 

measures that are required to minimize potential adverse impacts. Finally, this 

chapter provides a summary table of the environmental consequences associated 

with each alternative. 

• Chapter 3 – Affected Environment and Environmental Consequences: This 

chapter describes the environmental effects of implementing the proposed action 

and other alternatives, including no action. Within each section, the affected 

environment is described first, followed by a discussion of the potential effects of 

each alternative. 

• Chapter 4 – Agencies and Persons Consulted: This chapter identifies persons 

who contributed to the preparation of this EA and lists agencies and persons 

consulted during the NEPA process. 

• Chapter 5 – Environmental Laws and Directives: This chapter lists Federal 

environmental laws and directives that are relevant to the project. 

• Chapter 6 – Literature Cited: This chapter lists documents used in preparation of 

this EA. 

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Native Fish Restoration in Redrock Canyon 4
• Appendices: The appendices provide more detailed information to support the 

analysis presented in this EA. 

1.2 BACKGROUND 

1.2.1 The Redrock Canyon Watershed 

The proposed project would be implemented in the watershed 1 of Redrock Canyon in the 

Canelo Hills of Santa Cruz County in southeastern Arizona (Figure 1). It is located on 

the CNF, with the exception of two small private inholdings, which are located at 

Redrock Ranch in the center of the basin and at Cott Tank in the uppermost portion of the 

basin. No state, tribal, or other lands are included in the project area. There are about 

20,000 acres in the Redrock Canyon watershed, ranging in elevation from approximately 

5,900 feet at the crest of the Canelo Hills to 4,075 feet near the mouth (Figure 2). 

The primary stream course in Redrock Canyon is Redrock Canyon proper, which flows 

seasonally from upstream of Down Under Tank downstream to join with Harshaw 

Canyon and from there into Sonoita Creek in the town of Patagonia. Other named stream 

courses within the watershed include Oak Grove Spring Canyon, Lampshire Canyon, and 

the Cott Tank drainage. Areas of perennial or semi-perennial water are located 

throughout the watershed in streams, cienegas, springs, and stock tanks. Stock tanks may 

occupy sites of former natural springs. Primary areas of water that will be referred to in 

this EA are West Redrock Exclosure,2 Falls and Falls Exclosure, Gate Spring and Gate 

Spring Exclosure, Cott Tank Exclosure (including Cott Tank drainage and Redrock 

Canyon proper below its confluence with Cott Tank drainage), and a developing semiperennial area referred to as “above Redrock Ranch” (Figure 2). A number of named and 

unnamed springs exist. Stock tanks, small dams, watering troughs, wells, and trick tanks 

are scattered throughout the watershed. These are used primarily for livestock water, but 

a few were constructed for wildlife purposes. The location and status of all stock tanks 

and dams are described in Chapter 3. 

Redrock Canyon is the largest of the Canelo Hills tributaries to Sonoita Creek. Sonoita 

Creek drains the east side of the Santa Rita Mountains, the north-central portion of the 

Patagonia Mountains, and the western side of the Canelo Hills before entering the Santa 

Cruz River near the town of Rio Rico. The Santa Cruz River is a north-flowing tributary 

of the Gila River and one of its major contributing systems. The Gila River basin is a 

complex watershed that is tributary to the Colorado River near the town of Yuma. It 

drains most of southern and central Arizona, southwestern New Mexico, and areas of 

northern Sonora, Mexico. 

 

1

 A watershed (also known as a basin or catchment) is the area above a specific point in a stream or stream 

system in which all water drains towards the stream. This includes all areas up to ridgelines, from where 

precipitation flows downhill to the stream. 

2

 Exclosures are fenced areas intended to exclude livestock. 

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6
Figure 2. Locations and major features in Redrock Canyon watershed. 

 

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1.2.2 Aquatic Fauna in the Redrock Canyon Watershed and Gila River Basin

Redrock Canyon watershed supports a subset of the Gila River basin native3 aquatic 

fauna (see Appendix A, Table A-1). Four species of native fish are known from the 

canyon, including longfin dace, speckled dace, desert sucker, and endangered Gila 

topminnow4

. Several native amphibians are present in the watershed, most notably the 

federally listed threatened Chiricahua leopard frog and endangered Sonora tiger 

salamander. Three aquatic or semi-aquatic reptiles occupy Redrock Canyon watershed: 

Sonora mud turtle, black-necked gartersnake, and possibly Mexican gartersnake. 

The aquatic ecosystems of the Gila River basin have been highly modified by humans, 

resulting in a significant decline in the native aquatic fauna (see Appendix B, Table B-1). 

Gila River basin native fishes are now among the most endangered species in the United 

States. Of the 21 species of fish native to the basin, one is extinct and six have been 

extirpated, although three have been repatriated with limited success. Eleven are 

federally listed as threatened or endangered, and one is formally recognized as warranted 

for Federal listing. The State of Arizona lists 14 as species of concern (AGFD 1996). Of 

the seven species not listed by the Federal or state government, all but two are identified 

as declining and in need of protection (Desert Fishes Team 2004). 

Many of the Gila River basin native amphibian populations are also declining, 

particularly those tied to perennial surface water. Of the native amphibians of the Gila 

River basin, two are federally listed as endangered or threatened (Chiricahua leopard frog 

and Sonora tiger salamander), and one is managed through a conservation agreement inlieu of listing. Seven are listed by the State of Arizona as species of concern (AGFD 

1996). In addition, two Gila River basin native gartersnakes (narrow-headed gartersnake 

and Mexican gartersnake) are in serious decline (Holycross et al. 2006). 

The decline in distribution and abundance of native aquatic species in the Gila River 

basin mirrors other declines throughout the Southwest; many of which have resulted from

more than 150 years of habitat modification and destruction, as well as the introduction 

and spread of nonnative species by humans. Major portions of Arizona’s surface waters 

have ceased flowing because of water diversion, draining, and ground-water pumping, 

while others have been converted from flowing streams and springs into impounded 

reservoirs, ponds, and stock tanks (Hendrickson and Minckley 1984; Rogge et al. 1995; 

Logan 2002; Mueller and Marsh 2003). These losses severed connectivity between 

streams and fragmented populations of fish and other aquatic species (Fagan et al. 2002). 

Water development and poor watershed practices dramatically altered riverine habitats, 

which also contributed to sharp declines in native fishes (Minckley et al. 1997). 

Accelerated erosion, sedimentation, channel downcutting, and other changes in channel 

 

3

 “Native” (also indigenous, endemic, and aboriginal) refers to organisms that occur, or formerly occurred, 

in a particular region as a result of evolutionary or ecological processes. This is as opposed to organisms 

that have been intentionally or accidentally introduced outside their natural historic ranges by human 

activity. Organisms translocated outside their natural range by human activities are referred to as 

“nonnative” (also exotic, alien, introduced, nonindigenous, and invasive). 

4

 For scientific names of all mentioned species, see Tables 1, 2, 6, and 7. 

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Native Fish Restoration in Redrock Canyon 8
morphology commonly resulted from grazing, mining, timber harvest, roads, and other 

land use practices, caused loss or degradation of aquatic habitats (Cooke and Reeves 

1976; Dobyns 1981; Bahre 1991). Physical and biological destabilization of riverine 

systems has led to a typical pattern in Arizona where native species tend to be restricted 

to the upper reaches of major drainage basins (FWS 2001b). 

While initial declines in fish and amphibian populations resulted primarily from habitat 

destruction and modification, the effects of nonnative species are now the major 

contributing factor to declines and are a substantial impediment to successful restoration 

actions (Minckley 1991; Clarkson et al. 2005; Marsh and Pacey 2005). Approximately 

40 nonnative fish species are established in the Gila River basin (see Appendix B, Table 

B-2). In addition, other nonnative aquatic species such as bullfrogs (Rana catesbeiana) 

and crayfish (primarily Orconectes virilis) have become major pests that seriously impact 

native fish, amphibians, and aquatic reptiles (Hayes and Jennings 1986; Rosen and 

Schwalbe 1995; Carpenter and McIvor 2000; Carpenter 2005). 

Introduction and spread of nonnative aquatic species in the Gila River basin have 

occurred for a variety of reasons (see FWS 2001b for a review of mechanisms). Some 

are purposefully introduced to increase the diversity of, or food for, the sport fishery; for 

biological control; or for ornamental use. Others are accidentally released as bait or 

aquaculture species or introduced as a result of human transfers of water. Regardless of 

their mode of arrival, nonnative fishes have had a drastic detrimental effect on native 

aquatic species. 

Direct impacts of nonnative fishes and other aquatic species to native forms include 

predation, competition, hybridization, habitat alteration, and parasite and pathogen 

transmission (Propst and Bestgen 1991; Minckley 1991; Douglas et al. 1994; Fernandez 

and Rosen 1996; Rosen and Schwalbe 2002; Bonar et al. 2004). Predation on early life 

stages (eggs, larvae, juveniles) is considered the primary avenue by which nonnative 

species depress and often eliminate what are considered predator-naive native species 

(Minckley 1991; Johnson et al. 1993; Kupferberg 1997; Snyder 2006). These effects are 

often exacerbated by habitat degradation. Yet, history shows that aquatic species as 

diverse as the “big river” razorback sucker, diminutive Gila topminnow, and Sonora tiger 

salamander can live and reproduce in degraded habitats as long as they are 

unaccompanied by nonnative fishes, but that they commonly wane or disappear when 

nonnatives become established (Minckley et al. 1977; Marsh et al. 1998; Pacey and 

Marsh 1998; Collins and Snyder 2002). 

In Redrock Canyon, five nonnative species have invaded to date: western mosquitofish, 

largemouth bass, green sunfish, bluegill, and bullfrogs. The most recent date of their 

documented occurrence in Redrock Canyon is shown in Appendix A. All of these 

nonnatives have been present since the late 1970s; however, while largemouth bass, 

green sunfish, and bluegill have declined and may be gone, mosquitofish and bullfrogs 

have multiplied and spread throughout the basin. 

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Native Fish Restoration in Redrock Canyon 9
All of the nonnative fishes appear to have originated as stockings into grazing stock tanks 

within the basin. These apparently were not authorized or recorded stockings, but by the 

late 1970s and early 1980s, most of the records for largemouth bass and all of the records 

of green sunfish, bluegill, and mosquitofish were from stock tanks. By 1985, mosquitofish were documented in streams in the center of the basin; and, by 1987, largemouth 

bass and green sunfish were common in the upper stream reaches. Largemouth bass 

became so abundant throughout the Cott Tank drainage that a mechanical removal effort 

was undertaken in 1989 to reduce adverse impacts to Gila topminnow (Stefferud 1989). 

The ongoing drought in the southwest exacerbates the nonnative impacts to native species 

of the Redrock Canyon basin. The declining amount of surface water available increases 

losses to predation as the prey loses the ability to avoid the predator. The Gila 

topminnow appears to be less tolerant of crowding than are mosquitofish, thus giving 

mosquitofish a competitive edge during drought conditions (Dean 1987). 

1.2.3 Biological Opinion for the Central Arizona Project (CAP)

Congress passed the Colorado River Basin Project Act (Act) in 1968. This Act 

authorized the Secretary of the Interior, through Reclamation, to construct the CAP to 

deliver Colorado River water for agricultural, industrial, and municipal uses in central 

and southern Arizona. The CAP, which was declared “substantially complete” in 1993, 

conveys Colorado River water through a 336-mile-long system of pumping plants, 

aqueducts, dams, and reservoirs. 

During the late 1980s, the issue of introduction and spread of nonnative aquatic species 

through the CAP began to receive serious consideration among fisheries biologists. 

Because the CAP is an interbasin water transfer system, concern was expressed by 

wildlife resource management agencies that the CAP could accelerate the rate at which 

nonnative species are spread across basins and invade habitats occupied by threatened or 

endangered native fishes. In 1991, Reclamation requested formal consultation with the 

FWS, pursuant to Section 7(a)(2) of the Endangered Species Act (ESA). In 1994 and 

2001, the FWS issued biological opinions on the delivery of CAP water to the majority of 

the Gila River basin (FWS 1994, 2001b). 

The FWS concluded that interbasin water transfer through the CAP seriously and 

adversely affects the endangered Gila topminnow and razorback sucker and the 

threatened spikedace, loach minnow, and bald eagle5. The FWS also determined that 

CAP operations adversely modify critical habitat of the razorback sucker, spikedace, and 

loach minnow. The potential for establishment of nonnative species within the CAP 

system, and their subsequent escape and invasion into habitats occupied by protected 

native fishes, were cited as reasons for these adverse effects. Canal systems using CAPsupplied water and associated irrigation releases to the rivers of the Gila River basin, 

were identified by the FWS as principal routes, among others, by which nonnative 

species could move from the CAP to the Gila River and its tributaries. 

 

5

 The bald eagle was delisted from the ESA on August 8, 2007. 

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Native Fish Restoration in Redrock Canyon 10
The conservation measures developed for the 2001 biological opinion and modified in an 

ongoing reconsultation with FWS regarding the CAP require the construction of droptype fish barriers for controlling spread into native fish habitats by nonnatives that could 

be introduced through the CAP. To date, four barriers have been completed on three 

streams in Arizona,6 and several others are in planning and design. The proposed 

Redrock Canyon aquatic ecosystem restoration project (which includes a fish barrier) 

would partially satisfy these required conservation measures. The ongoing reconsultation 

considers CAP effects to the newly listed Sonora tiger salamander, Chiricahua leopard 

frog, and Gila chub. Fish barriers built pursuant to the FWS biological opinions are all 

subject to NEPA compliance. In addition, the barrier proposed for Redrock Canyon is 

not yet part of a final biological opinion and would require Section 7 consultation, along 

with other elements of the proposed project. 

1.3 PURPOSE OF AND NEED FOR ACTION 

The purpose of the proposed project is to restore and protect populations of native fishes 

and amphibians throughout all appropriate areas of the Redrock Canyon basin. In order 

to achieve this goal, all nonnative fishes must be removed, and the basin must be 

managed to prevent their reinvasion. In addition, populations of nonnative bullfrogs must 

be significantly reduced or eliminated. The purpose of the proposed action is to establish 

self-sustaining populations of five fish species (Gila topminnow, Gila chub, desert 

sucker, speckled dace, and longfin dace), Chiricahua leopard frog, Sonora tiger 

salamander, and possibly other aquatic and semi-aquatic native species. 

Opportunities for restoration of native fishes and amphibians of the Gila River basin are 

limited because the physical changes that many rivers and streams have undergone make 

them unsuitable for native fish restoration (e.g., drying, damming). In addition, 

challenges to removing nonnatives and controlling their reinvasion and land ownership 

patterns preclude many areas from native fish and amphibian restoration. 

Redrock Canyon is a rare and outstanding example of an area with the potential for 

successful restoration of imperiled species throughout a drainage basin. This project is 

needed for the following reasons. 

• A decline of native fishes and amphibian populations in Redrock Canyon has 

continued despite habitat improvement, and it appears to be directly linked to the 

presence of nonnative fishes and bullfrogs. 

• The Forest Service, over the past 15 years, has devoted considerable effort to 

protection and enhancement of Redrock Canyon and its aquatic fauna. This effort 

may be negated unless control and removal of nonnative species occurs. 

• Present drought conditions concentrate nonnative fish and amphibians into small 

areas, which provide optimal conditions for their removal. 

 

6

 Fish barriers have been constructed on Aravaipa Creek, Fossil Creek, and Sonoita Creek. Construction of 

a fifth barrier is underway on Bonita Creek. 

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Native Fish Restoration in Redrock Canyon 11
• Nonnative fish originating from Sonoita Creek are capable of reinvading the 

Redrock Canyon watershed, and natural barriers to their reinvasion afford 

protection only to the upper watershed. A constructed drop-type fish barrier is 

needed in lower Redrock Canyon to prevent nonnative fish reinvasions from 

downstream. 

• Nonnative fish also are present in stock tanks within the Redrock Canyon basin 

and are sources of reinvasion to other aquatic habitats in the watershed. 

Therefore, removal of nonnative fishes from stock tanks is also needed. 

• The severe depletion or elimination of native fishes and amphibians from the 

Redrock Canyon basin will require transplantation from other populations in order 

to restore the full complement of native aquatic species originally present in the 

basin. 

1.4 SUMMARY OF PROPOSED ACTION 

The proposed action would be implemented by Reclamation, in cooperation with the 

Forest Service, the AGFD and the FWS, to meet the purpose and stated in Section 1.3. It 

would include construction of a fish barrier in Redrock Canyon; removal of nonnative 

fish and frogs using integrated methods, including application of a commercially 

available piscicide; and augmentation, transplant, or reintroduction of native fish and 

amphibians. 

With the exception of the first item (fish barrier), all elements of the project described 

below are common to the two action alternatives discussed in this EA. Removal and 

restoration actions would be a collective effort among the Forest Service, Reclamation, 

AGFD, and FWS. The AGFD would consider approval of all activities associated with 

native species capture, holding, and transplant. Additional details about the proposed 

action and alternatives are presented in Chapter 2. 

• Fish barrier – Reclamation would build a reinforced poured-concrete fish barrier 

in lower Redrock Canyon approximately 4.25 miles upstream of Sonoita Creek. 

The barrier is intended to create an effective impediment to upstream movement 

of fish. This would include fish from Sonoita Creek and Patagonia Lake, both 

now and in the future. It would also act as a control site for eradication of 

nonnative fishes upstream in the Redrock Canyon watershed, preventing their 

reinvasion after removal. 

• Native species salvage – Prior to stream renovation, Reclamation, Forest Service, 

AGFD, and FWS personnel would salvage a portion of the native fish, amphibian, 

Mexican gartersnake, and turtle populations from Redrock Canyon. These would 

be held temporarily on site or at other appropriate locations and returned to the 

stream following removal of nonnative species. 

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Native Fish Restoration in Redrock Canyon 12
• Nonnative fish and frog removal – Nonnative fish and bullfrogs would be 

removed from the Redrock Canyon watershed using an integrated control 

approach. All nonnative fish would be eradicated from the drainage using the 

piscicides rotenone and antimycin A. Various mechanical methods would be 

used to remove adult bullfrogs, including netting, gigging, shooting (firearms), 

and euthanization. Stock tanks and stream pools would be pumped to lower 

water levels to facilitate bullfrog removal. 

• Restoration of native fishes and amphibians – A suite of five native fish species 

and two rare amphibians potentially would be restored in all appropriate locations 

with suitable habitat within the Redrock Canyon watershed. These include 

longfin dace, speckled dace, desert sucker, Chiricahua leopard frog, Gila chub, 

Gila topminnow, and Sonora tiger salamander. In addition, Sonora mud turtle 

would be salvaged and restocked during treatment. The project may also benefit 

native Mexican gartersnake, a rare species that may inhabit Redrock Canyon. 

• Monitoring – Post-treatment monitoring would be conducted to assess the success 

of the nonnative removal and native species restoration. Monitoring would 

continue for a minimum of 5 years after the nonnative removal. Post-treatment 

monitoring would incorporate results of existing ongoing monitoring efforts in the 

Redrock Canyon watershed. Also, the Forest Service would assume 

responsibility for “first-line” inspection of the fish barrier following flood events. 

Long-term maintenance of the barrier would be performed by the Central Arizona 

Water Conservation District (CAWCD). 

1.5 DECISIONS TO BE MADE 

Reclamation must decide whether to implement the proposed action, another action 

alternative, or no action. The Forest Service (Coronado National Forest Supervisor) must 

decide whether or not to authorize the use of NFS lands for implementation of the 

project. If the Forest Service authorizes the proposed action, Reclamation would 

construct the fish barrier in Redrock Canyon on NFS land. 

In addition to approving the barrier, the Forest Service must decide whether to approve 

the mechanical and/or chemical treatment of surface waters in the watershed by AGFD, 

which may include (1) the application of piscicide (antimycin A and/or rotenone) to 

cienega pools, stream sections, and stock tanks; and (2) seining, netting, gigging, 

pumping, or other mechanical methods to remove bullfrogs from cienega pools, stream 

sections, and stock tanks. Removal and restoration actions would be a joint effort 

involving the Forest Service, Reclamation, AGFD, and FWS. The AGFD would consider 

approval of all activities associated with native species capture, holding, and transplant. 

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Native Fish Restoration in Redrock Canyon 13
1.6 CONSISTENCY WITH CORONADO NATIONAL FOREST PLAN 

The Coronado manages NFS land in the Redrock Canyon watershed in accordance with 

the Coronado National Forest Land and Resource Management Plan (LRMP) (LRMP; 

USFS 1986, as amended) and other national policy and direction, including the ESA. 

The proposed action was determined to be consistent with the goals, objectives, 

standards, and guidelines in the LRMP. The LRMP provides direction for the Coronado 

to allow the construction of fish habitat improvement structures as needed to support 

populations of threatened and endangered species. It also guides the transplanting of 

protected species into suitable habitat following guidelines or species recovery plans and 

memoranda of understanding. No amendments to the LRMP would be necessary to 

allow the proposed action to be implemented on NFS land. 

1.7 PUBLIC INVOLVEMENT 

The Council on Environmental Quality defines scoping as “...an early and open process 

for determining the scope of issues to be addressed and for identifying significant issues 

related to a proposed action” (40 CFR 1501.7). Scoping is an important underpinning of 

the NEPA process that encourages public input and helps focus the environmental impact 

analysis on relevant issues. Distribution of scoping information typically heralds the 

beginning of the public component of the NEPA process. 

The project was listed on the CNF web site (www.fs.fed.us/r3/coronado) in a Schedule of 

Proposed Actions on January 1, 2007. On January 18, 2007, Reclamation posted a 

scoping notice on its Phoenix Area Office web site (www.usbr.gov/lc/phoenix) and 

mailed scoping information on the proposal to 53 potentially interested individuals, 

organizations, and agencies. In addition, a scoping meeting was held in Sonoita on 

February 8, 2007, to discuss the project with grazing permittees who have allotments 

within the project area. Reclamation and CNF received 11 letters of comment (including 

electronic mail) during the 30-day scoping period which ended on February 16, 2007. 

Six commenters responded favorably, and four commenters expressed opposition to the 

project. One responder advised the agencies that the proposed fish barrier would require 

a Floodplain Use Permit prior to construction. 

The interdisciplinary team evaluated the issues raised during public scoping and 

categorized each according to possible significance or lack thereof. Relevant issues were 

defined as those that form the basis for alternative development, increased analysis, or the 

implementation of mitigation. Nonrelevant issues are those that are: (1) not within the 

scope of the project; (2) already decided/required by law, regulation, or other previous 

decisions; (3) unrelated to the decision being made; and, (4) conjectural and not 

supported by scientific or public interest. 

Based on comments received during public scoping, the Forest Service and Reclamation 

identified the following significant issues: 

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Native Fish Restoration in Redrock Canyon 14
• Effects of the project on nontarget species

• Effects of the project on water quality and quantity

• Effects of the project on visual aesthetics and scenery

• Effects of the project on livestock grazing

• Effects of the project on soils 

In accordance with Forest Service regulations codified at 36 CFR 215.6 and Reclamation 

guidelines, the public will be offered a 30-day period to review this pre-decisional EA. 

Persons who offer oral or written comments on the EA or who otherwise express an 

interest in the project during the period will have a right to appeal a subsequent decision 

on its implementation following legal notice of the decision, pursuant to 36 CFR 215.6. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 15
CHAPTER 2 -- DESCRIPTION OF THE ALTERNATIVES 

This chapter describes the alternatives considered for the restoration project in greater 

detail. These include two action alternatives and no action. Also described are three 

alternatives that were considered but eliminated from further evaluation. 

2.1 NO ACTION 

In accordance with CEQ regulations at 40 CFR 1502.14 (d), no action must be considered 

as an alternative in each NEPA review. No action provides the baseline for comparison 

of environmental effects of the action alternatives. If no action is taken, Reclamation 

would not construct the proposed fish barrier, there would be no stream renovation, and 

native fish and amphibian restoration would not occur. 

2.2 PROPOSED ACTION

The proposed action consists of five elements: (1) construct a barrier to prevent upstream 

incursion by nonnative fish; (2) salvage native fish, amphibians, and aquatic reptiles from 

waters of Redrock Canyon; (3) apply the piscicides antimycin A and rotenone and use 

mechanical methods to eradicate all nonnative fish in the watershed above the 

constructed barrier and reduce or eliminate bullfrog; (4) restore populations of native 

fish, frogs, salamanders, and semi-aquatic reptiles to all appropriate waters in the 

watershed; and, (5) monitor the aquatic fauna of the watershed following treatment and 

restoration actions. 

Prevention of nonnative fish reinvasion is critical to the long-term success of Redrock 

Canyon aquatic ecosystem restoration. The fish barrier is an important measure to secure 

the western end of the project area against nonnatives invading from downstream. Other 

potential routes of reinvasion, such as stock tanks, would be addressed by proposed 

piscicide and mechanical treatments and by the continuation of Forest Service land and 

water management practices, which incorporate the recommendations and requirements 

of several biological opinions and the CNF Stockpond and Aquatic Habitat Management 

and Maintenance Guidelines for the Chiricahua Leopard Frog. 

2.2.1 Fish Barrier 

Site Selection. Potential sites for a constructed barrier were identified during on-theground surveys by fishery biologists from Reclamation, the Forest Service, AGFD, FWS, 

and biologists knowledgeable of Redrock Canyon and its aquatic fauna. Only sites in the 

lower drainage were considered in order to maximize the length of stream protected and 

minimize fragmentation of the resident population of Gila topminnow. A site 

approximately 4.25 miles upstream of the confluence with Sonoita Creek and 1 mile 

upstream from the CNF boundary was determined by Reclamation to be geologically 

suitable for placement of a barrier (Figures 3 and 4). 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 16
Figure 3. Proposed fish barrier construction site and staging area. 

The proposed barrier would protect an estimated additional 7 miles of stream habitat 

from invasion by nonnatives compared to the area currently protected by natural barriers 

(see Alternative A). Approximately 1.5 miles of this additional habitat includes a nearperennial reach which historically has provided habitat for Gila topminnow and other 

native fishes (especially speckled dace and desert sucker). Protection of the more 

ephemeral stream reaches behind the barrier, which include short reaches of perennial 

water, would allow populations of Gila topminnow and other aquatic organisms to 

increase should a genetic bottleneck7

 occur, which is often the case during severe 

drought. Population expansion during favorable (wet) watershed conditions may prevent 

fixation of deleterious genetic variants that are often typical of small populations. Such 

“genetic rescue”8

 is an important element in the conservation of rare species (Hedrick 

1995, Ingvarsson 2001). The additional stream length protected behind the constructed 

barrier will enhance metapopulation9

 dynamics for all species, thereby benefitting 

population genetics and population persistence. 

Fish Barrier Construction. A reinforced poured-concrete drop structure would be 

constructed in a 10-foot-wide bedrock constriction of the channel located within the West 

Redrock Exclosure. The barrier would be anchored to abutment bedrock and keyed into 

 

7

 When population numbers are temporarily reduced to a level insufficient to maintain the genetic diversity 

in the population 

8

 An increase in population fitness owing to immigration of new alleles 

9

 A set of local populations within some larger area, where typically migration from one local population to 

another is possible 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 17
the channel alluvium to ensure stability against water-transported debris and erosive 

forces typically associated with high magnitude flows. Placement of the keys and rock 

gabions would require excavation of a temporary 7-foot-deep trench in the channel 

alluvium between the bedrock abutments. Stream flow, if present, would be diverted 

around the trench during construction. 

The proposed fish barrier would consist of five primary features (see Appendix C, Figure 

C-1 and C-2): (1) a 5-foot-high concrete drop structure to preclude upstream incursion of 

fishes; (2) secondary 1- to 3-foot-high concrete walls to fill low spots in bedrock along 

the left and right abutments; (3) a 10-foot-wide concrete apron spanning the length of the 

drop structure to prevent streambed scour and plunge pool development; (4) upstream 

and downstream keys to help anchor the barrier and prevent scour from undermining the 

structure; and, (5) gabion or riprap armoring across the entire width of the streambed 

along the upstream and downstream keys. 

Placement of the keys and gabions or riprap would require excavation of a temporary 

7-foot-deep trench in the channel alluvium between the bedrock abutments. Stream 

flows would be diverted around the trench, and one or two 10-foot-deep dewatering wells 

would be installed to keep the trench dry during construction. Construction would 

require minimal travel of small equipment, such as a backhoe and truck-mounted drill rig, 

over 0.7 miles of stream channel. A single vehicle would be parked at the barrier site 

during construction for emergency use in the event of injury, or for occasional transport 

of food, water, and construction supplies. Construction personnel would walk to the site 

from the existing road or staging area, and vehicles would not be used in the riparian 

corridor for routine transport of personnel. This area is presently used by vehicles only in 

its lower end on a sporadic basis. Earlier routes of Forest System Road (FSR) 138 

through Redrock Canyon have used all or part of this section of stream channel. 

Concrete would be hauled from commercial off-site batch plants and transported to the 

site by helicopter. At the completion of barrier construction, the channel would be 

rehabilitated by obliterating vehicle tracks and recontouring of some areas, if necessary. 

Primary staging of machinery and equipment would occur on one of two benches above 

the stream, adjacent to the FSR 138 low-water crossing (Figure 3). Staging activities 

would include unloading and storage of materials and supplies, equipment storage, and 

parking. The staging area would not exceed 1/2 acre in size. Temporary lay down of 

construction materials may occur on the terrace on the north side of the stream at the 

barrier site, but hazardous materials would not be stored there. Total disturbed area at the 

barrier site is expected to be approximately 0.12 acres. All reasonable efforts would be 

made to minimize removal of trees, and site rehabilitation would occur following project 

completion. The volume of construction traffic is expected to be low, and no disruption 

of public access is anticipated. Construction would require approximately 1.5 months. 

Inspection and maintenance of the fish barrier would be necessary on a periodic basis, 

particularly following significant flooding. The Forest Service would be responsible for 

first-line inspection following flood events, and CAWCD would be responsible for 

maintenance. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 18
2.2.2 Native Species Salvage 

The AGFD has statutory authority to manage fish and wildlife resources of Arizona and 

ultimately would approve and oversee activities associated with native species salvage, 

bullfrog control, and native fish, amphibian, and aquatic reptile transplant. Native 

species salvage would begin several days prior to application of antimycin and/or 

rotenone. 

Currently, there are three captive populations of Gila topminnow derived from 

individuals taken from the Cott Tank drainage and Falls area in 2002. Because of the 

strong resemblance between Gila topminnow and nonnative mosquitofish, any salvaged 

fish believed to be Gila topminnow would be quarantined in aquaria for absolute 

identification before being added to existing captive stocks. Identification of each 

individual Gila topminnow would be confirmed at both the salvage and release of 

quarantine stages by independent inspections by at least three biologists knowledgeable 

of, and with substantial experience in, discrimination of Gila topminnow from 

mosquitofish. Individuals would be released from quarantine only after they attain 

sufficient size for adequate identification (>40 mm). After the two-stage quarantine and 

identification process, salvaged Gila topminnow would be placed into captivity at a 

location(s) yet to be determined. Fish identifications would be confirmed by at least two 

biologists knowledgeable of, and experienced with, these species at the time of salvage 

and again before these fish are restocked into any natural habitat. 

Chiricahua leopard frog is the only native ranid frog known from the Redrock Canyon 

watershed. Before application of piscicides, efforts would be made to locate and salvage 

Chiricahua leopard frogs. Any individuals salvaged, of any life stage, would be removed 

to a temporary holding facility, either on site or at an appropriate AGFD-approved 

facility elsewhere. Identification upon salvage and upon release from quarantine would 

be confirmed by at least two biologists knowledgeable of, and experienced with, 

identification of these species and their discrimination from bullfrogs. 

Prior to application of piscicides, salamanders would be salvaged and placed into a 

temporary holding facility, either on site or at an appropriate location elsewhere. Any 

stock tank with water present would be sampled prior to piscicide application to test for 

salamander presence. Salamanders from each tank would be held separately because of 

the inability to make definitive identifications as to subspecies. No salamanders would 

be returned to the wild until their subspecific identification has been confirmed by 

genetic analysis. 

Sonora mud turtles are common native occupants of waters of Redrock Canyon. There is 

some indication that rotenone is toxic to freshwater turtles (Fontenot et al. 1994; McCoid 

and Bettoli 1996). During salvage operations for fish, frogs, and salamanders in Redrock 

Canyon, Sonora mud turtles would be salvaged and held in temporary holding facilities, 

either on site or at an appropriate location elsewhere. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 19
Mexican gartersnake is a possible, but unverified, inhabitant of the cienega-like habitats 

of upper Redrock Canyon and Cott Tank drainage. If individuals are found during 

project activities, they would be salvaged and placed into holding facility identified by 

AGFD. 

Salvaged native species would be captured using a combination of dip nets, seines, hoop 

nets, minnow traps, electrofishing, and other appropriate techniques. Fish, tadpoles, and 

larval or branchiate adult salamanders would be transported from the site of capture to 

holding tanks via 2- or 5-gallon buckets containing stream water and battery-powered air 

stones. Adult frogs, turtles, gartersnakes, and metamorphosed salamanders would be 

transported in buckets or other containers. Location of salvage holding facilities for 

longfin dace, desert sucker, speckled dace, and native amphibians cannot be specifically 

identified at this time. Temporary holding in aerated tanks or soft-sided swimming pools 

may occur on site. Although detoxification of the stream would occur within a week, not 

all salvaged fish and amphibians may be returned immediately, depending on water 

conditions and continued presence of bullfrogs or other nonnative animals in Redrock 

Canyon. If longer-term holding is required, stocks may be transferred to appropriate 

holding facilities. 

Water for temporary on-site holding facilities may be obtained from the stream, from 

water transported in from elsewhere, or from groundwater from an area well. All water 

placed into the holding facilities would be screened with fine mesh to ensure that no 

nonnative fish or amphibians are inadvertently introduced into the holding facilities. Any 

water transported from outside the basin would be from a source that is guaranteed free 

of nonnatives and pathogens, such as groundwater or treated water. All holding site 

facilities and equipment would be treated in accordance with protocols in the Chiricahua 

leopard frog recovery plan (FWS 2007) to prevent the spread of chytrid fungus and other 

diseases. 

2.2.3 Nonnative Fish and Frog Removal 

Nonnative fish and frogs would be eradicated from all surface waters in Redrock Canyon 

using an integrated approach (Dawson and Kolar 2003) that includes several removal 

techniques combined with invasion preventatives and management to reduce the risk of 

invasion. Two of the target nonnatives, mosquitofish and bullfrogs, have been known to 

move throughout the watershed using small, isolated, temporary waters; therefore, all 

surface waters, including stock tanks (Figure 4), located upstream of the constructed fish 

barrier would be subjected to nonnative removal efforts. 

Nonnative removal would also occur in two earthen stock tanks in Meadow Valley and 

any surface waters in the Meadow Valley drainage upstream of those tanks. Although 

the natural drainage of these tanks is a south trending tributary of the Santa Cruz River, 

they presently drain to Cott Tank in upper Redrock Canyon watershed via a constructed 

ditch and are thus an artificial “captured” portion of the Redrock Canyon watershed. 

This part of Meadow Valley would be in the treated area. Interbasin diversions from 

Meadow Valley to other pipelines and troughs or tanks within the Redrock watershed 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 20
would be inspected and a determination made as to whether or not they require treatment 

and nonnative removal. Other imports of water from outside the watershed (i.e. in upper 

Box Canyon and in Oak Grove Spring Canyon) would also be identified, inspected, and 

included in treatment, as necessary. 

Figure 4. Stock tanks in the Redrock Canyon watershed. 

Piscicide would be applied to all surface waters in accordance with the specifications of a 

Pesticide Use Proposal approved by the CNF Supervisor prior to application. Rotenone 

and antimycin A would both be used. Rotenone would be used in pools and tanks where 

it is more effective than antimycin A because it is less susceptible to detoxification by 

sediment, organic matter, aquatic vegetation, and light. Antimycin A would be used for 

areas of flowing water or in areas where piscicide may need to be applied in areas distant 

from a road. Antimycin A and rotenone are Environmental Protection Agency (EPA)-

registered piscicides that have been in widespread use in fisheries management (Meronek 

et al. 1996; Allen et al. 2006; also see Appendix D for annotated list of projects in 

Arizona that have used antimycin A). 

Total eradication of all nonnative fish is the objective. Some death of bullfrog tadpoles 

and eggs is expected, although because of their resistance to the piscicides, total 

eradication is not likely. Bullfrog tadpoles and eggs would be manually removed during 

salvage, piscicide application, and monitoring, then euthanized. Adult bullfrogs are not 

likely to be significantly affected by piscicides. Some would be captured by netting or 

gigging, while others would be dispatched mechanically, using firearms or other means. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 21
Both piscicides act at the cellular level to interrupt respiration in gill-breathing organisms 

ailable 

 certified pesticide applicator would be present during all piscicide applications. All 

ay 

contact 

s 

o ensure effectiveness of the treatment, a second piscicide application to all waters 

ars 

everal stock tanks known to support high density of bullfrogs would be pumped down 

. 

he project area is lightly used by the public but would be signed in English and Spanish 

o disposal of dead fish and frogs is expected to be necessary. The volume of carcasses 

 

and are nontoxic to humans and other non-gill-breathing organisms when applied at 

recommended concentrations. See Appendix E for detailed information on these 

piscicides. Rotenone would be used in the form of one of several commercially av

powdered or liquid formulations. Antimycin would be used in the commercial formula 

Fintrol® concentrate (liquid form of antimycin A) and Fintrol® 15 (antimycin A-coated

sand). 

A

product label requirements and safety precautions would be followed. Piscicides would

be applied using a variety of methods depending on surface water conditions. If areas of 

continuous flow are present, drip station applications would be used (Stefferud and 

Propst 1996; Weedman et al. 2005). In isolated pools and tanks, piscicide would be 

applied by backpack or shore-mounted sprayers or by bucket. Mechanical agitation m

be used to mix pooled water, where appropriate. Antimycin-coated sand would be spread 

over the water surface in deeper (>3 feet) areas. Concentrations of piscicide used would 

be within label directions, and application rates would be determined by estimates of 

pooled water volume or stream discharge in combination with bioassays that would 

determine the precise minimum dosages required to kill the target organisms. 

Application rates would be sufficient to maintain piscicide at toxic levels for a 

time of 8 hours for antimycin and 16 hours for rotenone (Gilderhus 1972). Effectivenes

would be monitored by use of live cages containing locally captured mosquitofish (and 

any other nonnative fish present at the site) and bullfrog tadpoles in each pool, tank, or 

area of flow. 

T

would occur within 2 weeks of the first treatment. Additional applications up to 4 ye

later may occur, depending on monitoring results. 

S

or dried completely, and all nonnative aquatic species found would be manually removed

These mechanical treatments to control bullfrogs would be repeated as necessary for up 

to 4 years. 

T

at key access points to notify users of considerations necessary to avoid exposure to 

treated waters. Reclamation and the Forest Service would work with permittees with

livestock on the four allotments within the project area (Seibold-Crittendon, Kunde, 

Papago, and San Rafael) to avoid any impacts to cattle or disruption to grazing 

operations. 

N

is anticipated to be small and would disappear within hours because of scavengers, 

desiccation, and decay. However, if necessary, disposal would be by on-site burial. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 22
No neutralization is expected to be necessary, unless needed to expedite return of 

salvaged Sonora tiger salamanders and Chiricahua leopard frogs. Potassium and sodium 

permanganate, which are acceptable chemicals for detoxifying rotenone and antimycin-A 

(Marking and Bills 1975), would be available on site during all piscicide application in 

case it is needed. Unless during application, surface water is flowing from inside the 

treatment area into other areas (i.e., downstream of the CNF boundary), no neutralization 

would be used. Detoxification would be allowed to occur through natural oxidation. 

Detoxification, either natural or chemical, would be determined using sentinel cages 

containing native fish and/or amphibians. 

2.2.4 Restoration of Native Fish and Amphibians 

Following successful nonnative removal, native fishes, Chiricahua leopard frog, Sonora 

tiger salamander, Sonora mud turtle, and Mexican gartersnake would be repatriated into 

Redrock Canyon. 

Gila topminnow. If any Gila topminnow are found during salvage they would be 

returned to the stream in the area of their capture following quarantine and a 

determination of treatment detoxification. Additional fish from captive populations of 

the species from Redrock Canyon would be restocked into Redrock Canyon watershed 

after the treatment area has been detoxified. If sufficient surface water to support Gila 

topminnow does not exist, the species would be stocked as soon as sufficient surface 

water becomes available. Population augmentation stocking would occur in all areas 

until a stable population has been established. 

Restocking would follow standard procedures of the ongoing Gila topminnow recovery 

program. 

Longfin dace. Longfin dace removed during salvage would be returned to the stream in 

the area of their capture following a determination of treatment detoxification. If less 

than 400 longfin dace are available from salvaged individuals, additional fish would be 

obtained from Harshaw Canyon, to which Redrock Canyon is confluent. Longfin dace 

taken from Harshaw Canyon would be quarantined and triple sorted by experienced 

individuals to ensure that no mosquitofish (which are present in Harshaw Canyon) are 

accidentally transported into Redrock Canyon. All transport water would be obtained 

from a guaranteed nonnative free source. Pathogen testing would not be necessary for 

Harshaw Canyon fish because they are from a source with frequent episodic connection 

with Redrock Canyon. Augmentation stockings may be repeated until a self-sustaining 

population is established 

Desert sucker. Desert sucker removed during salvage would be returned to the stream in 

the area of their capture following a determination of treatment detoxification. It is 

unlikely that many desert sucker would be found during salvage; therefore, reintroduction 

would be made from stocks obtained from Sonoita Creek (either above or below 

Patagonia Dam). Fish taken from Sonoita Creek would be quarantined and triple sorted 

by experienced individuals to ensure that no nonnative fish (several are present in Sonoita 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 23
Creek) are accidentally transported into Redrock Canyon. All water used to transport fish 

would be from a guaranteed nonnative-free source. Pathogen testing would be conducted 

on desert sucker if obtained below Patagonia Dam; and, if necessary, appropriate 

treatment would be given to ensure that the possibility of disease transmission is 

minimized. Augmentation stocking may occur until a self-sustaining population is 

established. 

Speckled dace. If any speckled dace are found during salvage, they would be returned to 

the stream in the area of capture following a determination of treatment detoxification. In 

addition, speckled dace would be restocked using fish obtained from Sonoita Creek 

above Patagonia Lake. Speckled dace taken from Sonoita Creek would be quarantined 

and triple sorted by experienced individuals to ensure that no nonnative fish (several are 

present in Sonoita Creek) are accidentally transported into Redrock Canyon. All water 

used in fish transport would be from a guaranteed nonnative-free source. Pathogen 

testing would not be necessary for Sonoita Creek fish obtained above Patagonia Lake, 

because they are from a source with frequent episodic connection with Redrock Canyon. 

Augmentation stocking may occur until a self-sustaining population is established. 

Gila chub. Although there no records of Gila chub in Redrock Canyon, cienega habitats 

in Cott Tank drainage are similar to those in other occupied locations, such as Sheehy 

Spring where Gila chub thrive and historically coexisted with Gila topminnow. Given 

completion of other required regulatory processes and dependent upon assessment of 

habitat suitability and feasibility, establishment of Gila chub into locations within the 

Redrock Canyon watershed may occur as part of this project. Provided that sufficient 

surface waters are present, Gila chub would be introduced into appropriate waters of 

Redrock Canyon, particularly the cienega pools in the Cott Tank drainage, following 

removal of nonnatives. The source and quantity of Gila chub to be reintroduced into 

Redrock Canyon would be determined as part of the recovery program for the species, 

but would be from within the Santa Cruz River subbasin. Because the chub is a federally 

listed species, ESA Section 7 consultation must be completed, and any subsequent 

provisions of the biological opinion would be incorporated into the proposed project. 

Chiricahua leopard frog. Chiricahua leopard frogs salvaged prior to treatment would be 

released back into the wild near the site of capture following a determination of 

detoxification and appropriate habitat conditions. Feasibility of augmentation of that 

population or restoration of Chiricahua leopard frog into other areas of the Redrock 

Canyon watershed has not yet been fully explored. Additional review is necessary to 

identify the highest priority sites and sources and mechanisms of transplant stock. Such 

efforts would be in accordance with the transportation and release protocols established 

in the recovery plan. Because the Chiricahua leopard frog is a federally listed species, 

ESA Section 7 consultation must be completed, and any subsequent provisions of the 

biological opinion would be incorporated into the proposed project. 

Sonora tiger salamander. Sonora tiger salamander salvaged prior to treatment would be 

released back into the wild near the site of the capture following a determination of 

detoxification and appropriate habitat conditions. Redrock Canyon is outside what was 

formerly thought to be the limits of its historic range, and recent confirmation of 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 24
salamanders discovered in Oak Tank as Ambystoma tigrinum stebbinsi has not yet been 

followed up with a thorough analysis of the potential for the species within the Redrock 

Canyon watershed. Expansion of Sonora tiger salamander into other areas of Redrock 

Canyon may occur as part of this project, depending upon assessment of habitat 

suitability and feasibility. These actions would be guided by the recovery plan. Because 

the Sonora tiger salamander is a federally listed species, ESA Section 7 consultation must 

be completed, and any subsequent provisions of the biological opinion would be 

incorporated into the proposed project. 

Sonora mud turtle. Sonora mud turtles salvaged during pre-treatment work would be 

returned to the wild near the site of capture following a determination of detoxification. 

Mexican gartersnake. Mexican gartersnakes that are salvaged during pre-treatment 

would either be returned to the wild near the site of capture or would be retained in 

captivity for breeding purposes. Upon attainment of sufficient captive stock, or using 

stock obtained from another appropriate source, Mexican gartersnake would be 

translocated into suitable habitats in Redrock Canyon watershed. 

2.2.5 Monitoring

Following the initial treatment, an intensive monitoring effort would target all waters 

within Redrock Canyon and Meadow Valley watersheds to which piscicide or other 

removal methods were applied. Methods would include visual observation, dip nets, 

minnow traps, seines, and other nets, electrofishing, and any other appropriate 

techniques. Monitoring would be conducted in cooperation with AGFD and FWS. The 

primary purpose of the monitoring would be to detect the presence or absence of 

nonnative fish and bullfrogs, but also to document presence/absence, relative abundance, 

reproduction, and recruitment of native fish, Chiricahua leopard frog, and Sonora tiger 

salamander. 

Following the initial 2 years’ post-treatment, fish monitoring would continue as spring or 

early summer monitoring conducted by AGFD as part of the Gila topminnow recovery 

program monitoring. Supplementing these existing efforts, additional monitoring of 

other surface waters of the basin and those of Meadow Valley drainage included in the 

treatment would occur at least once every other year when resources and funding are 

available. Monitoring of stock tanks within Redrock Canyon watershed and those in 

Meadow Valley that are presently diverted into Redrock Canyon also would be 

conducted to detect nonnatives. 

2.3 ALTERNATIVE A - NONNATIVE REMOVAL AND NATIVE 

RESTORATION WITHOUT BARRIER 

Under this alternative, no artificial barrier would be constructed. This would leave areas 

downstream of the natural barrier at the Falls open to invasion of nonnative fish from 

downstream in Sonoita Creek (Figure 4). Therefore, under this alternative, nonnative 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 25
aquatic species would be removed from the watershed only upstream of the existing 

natural barrier at the Falls and upstream of a set of natural barriers in upper Oak Grove 

Spring Canyon. The project area under Alternative A would differ from the Proposed 

Action in that about 1.6 miles of lower Redrock Canyon proper below the Falls, 2.2 miles 

of lower Oak Grove Spring Canyon, 1.8 miles of Oak Grove Spring Canyon tributaries, 

1.4 miles of an unnamed tributary to lower Redrock Canyon, and one stock tank (Dry 

Tank) would be omitted. Other than this difference in area to be included in the project, 

the parameters would be the same as those outlined in Sections 2.2.2 to 2.2.5 of the 

Proposed Action. 

Under Alternative A, native fish and amphibians would be restored into all suitable 

habitats in that portion of the watershed upstream of the Falls and in any suitable areas 

above the natural barriers in Oak Grove Spring Canyon. Restoration actions would 

follow the same parameters described in Section 2.2.4 of the Proposed Action, except that 

native species would not be restocked into any waters present in the 7 miles of Redrock 

Canyon and tributaries between the proposed artificial barrier site and existing natural 

barriers. 

Monitoring under Alternative A would have the same parameters as under the Proposed 

Action but would not include the omitted area. 

2.4 MITIGATION FOR ACTION ALTERNATIVES 

Mitigation measures are prescribed to avoid, reduce, or compensate for adverse effects of 

an action. The following measures will be implemented for the action alternatives, as 

noted: 

• Standard dust abatement best management practices (BMPs) will be used to 

minimize generation of airborne particulates during fish barrier construction 

(Proposed Action). 

• Sediment and erosion controls will be established where appropriate to protect 

water quality and soils during and after fish barrier construction (Proposed 

Action). 

• A Clean Water Act (CWA), Section 401, Water Quality Certification has been 

issued by the Arizona Department of Environmental Quality (ADEQ) for fish 

barrier construction. Terms and conditions of the certification will be integrated 

into the project (Proposed Action). 

• Reclamation received a programmatic CWA, Section 404, permit from the U.S. 

Army Corps of Engineers (COE) to construct fish barriers required under the CAP 

biological opinion. Terms and conditions of the 404 permit will be implemented 

to reduce adverse effects to water quality during construction. Mitigation for 

impacts to vegetation was previously implemented by Reclamation for Redrock 

Canyon and all other Arizona fish barriers proposed under the 2001 CAP 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 26
biological opinion. This mitigation consisted of acquisition of a Conservation 

Easement on 1,420 acres of land along the San Pedro River in southern Arizona, 

in cooperation with The Nature Conservancy. 

• A CWA, Section 402, Stormwater Pollution Prevention Plan, which specifies 

pollution-control BMPs has been prepared for fish barrier construction. Coverage 

under the Arizona Pollutant Discharge Elimination System (AZDPES) general 

permit for storm water discharges associated with fish barrier construction will be 

obtained (Proposed Action). 

• A Water Control Plan will be prepared with measures to protect water quality and 

care of the stream during fish barrier construction (Proposed Action). 

• Concrete used in barrier construction will be visually compatible with the colors 

of surrounding substrates (Proposed Action). 

• Signs of vehicle access to the barrier site will be obliterated following 

construction (Proposed Action). 

• All reasonable effort will be made to avoid the removal of any trees along the 

access route to the barrier site and at the staging area (Proposed Action). 

• Key public access points to Redrock Canyon will be posted in English and 

Spanish prior to application of the piscicide (both action alternatives). 

• The Forest Service’s Pesticide Use Proposal will clearly prescribe strict adherence 

to piscicide labels (both action alternatives). 

• Piscicide applications will be conducted only during periods of low stream flow 

by certified applicators (both action alternatives). 

• Stock pond treatments (pumping and piscicide applications) will be timed to 

avoid impacting livestock (both action alternatives). 

• Alternative water sources will be provided, as appropriate, for livestock affected 

by pumping of stock tanks or pools or stock tank reconfiguration (both action 

alternatives). 

• All construction equipment will be periodically inspected for leaks, which will be 

promptly corrected (Proposed Action). 

• Hazardous substances and fuels will be stored outside the 100-year floodplain of 

Redrock Canyon (Proposed Action). 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 27
2.5 ALTERNATIVES CONSIDERED BUT ELIMINATED FROM DETAILED 

ANALYSIS

Three alternatives were considered but eliminated from detailed analysis for various 

reasons. 

• Other fish barrier locations -- To be effective, a fish barrier on Redrock Canyon 

must be located as far downstream as feasible to maximize the area protected and 

avoid leaving significant portions of Redrock Canyon available to harbor 

nonnatives, thus giving them a higher probability for successful reinvasion. 

Important native species habitat is located in the stream reach in the West 

Redrock Exclosure, the reach below Pig Camp Spring, and the central portion of 

Oak Grove Spring Canyon (see Figure 2). To protect those areas, the barrier must 

be located downstream near the CNF boundary. Failure to protect those areas of 

stream would not fully meet the purpose and need. 

Reconnaissance-level field investigations of possible barrier sites in Redrock 

Canyon were conducted by fishery biologists from Reclamation, the Forest 

Service, AGFD, FWS, and biologists knowledgeable of Redrock Canyon and its 

fishes. No technically suitable barrier sites occur downstream of where the 

canyon widens considerably near the CNF boundary. Selection criteria for barrier 

sites between that point and the existing natural barrier at the Falls were: (1) the 

presence of a narrow bedrock channel in which to solidly anchor the barrier and 

minimize site impacts, (2) access that minimizes adverse impacts to the stream, 

and (3) proximity to the lowermost end of known native fish habitat to provide the 

maximum benefit. No sites meeting those criteria were found other than the site 

in the Proposed Action. 

• Fish barrier without nonnative removal and native species restoration -- This 

alternative would provide for construction of a fish barrier but would not remove 

the nonnative species present upstream from the barrier and would not restore 

populations of native fish and amphibians either through repatriation of extirpated 

species or expansion of existing populations of extant species. This alternative 

was not considered in detail because it fails to meet the purpose and need of this 

project. The continued presence of nonnative species within Redrock Canyon 

carries a high probability of complete extirpation of the only remaining native 

fish (Gila topminnow), Chiricahua leopard frog, and Sonora tiger salamander. 

Construction of a barrier without removing the existing nonnatives make the 

barrier essentially purposeless, as it would function only to prevent incursion of 

additional nonnative species and would do nothing to reverse negative impacts of 

nonnatives already present within the watershed. 

This alternative would not fulfill Reclamation’s commitments under the 2001 

revised and 1999 draft CAP biological opinions. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 28
Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 29

 

• Stock tank breaching -- Stock tanks are usually accessible by road and invite 

human use. They are an attractive nuisance10 that provides the opportunity for 

people to stock nonnative fish or amphibians they find desirable or to dump 

unwanted pets or ornamental animals. Artificial waters such as these also provide 

stepping stones that enable nonnative species, such as bullfrogs, to move across 

an otherwise dry landscape between natural surface waters (FWS 2007). When 

stock tanks are deemed necessary for other management objectives, such as 

livestock grazing, they can be managed both to meet the needs of the livestock 

operator and concurrently provide useful habitat, albeit artificial, for some native 

aquatic species. Because the stock tanks in the Redrock Canyon watershed are 

currently managed to minimize the risk of reinvasion by nonnatives, breaching 

was considered unnecessary at this time and eliminated from further 

consideration as an element of the proposed project. 

10 “Attractive nuisance” is a legal term referring to a potential harmful situation that is sufficiently inviting 

or interesting; it attracts a person who does not understand the risk (usually referring to a child) into taking 

dangerous actions. 
ish Restoration in Redrock Canyon 

2.6 COMPARISON OF ALTERNATIVES Table 4. Summary of environmental consequences by alternative. 

ALTERNATIVES RESOURCE NO ACTION PROPOSED ACTION ALT

Water Resources No effect. Short-term sediment increases during 

barrier construction. Short-term impact to surface waters scattered throughout about 30 miles of stream channel from piscicide application. 

Short-term impscattered throustream channeapplication. 

Vegetation No effect. Short-term, minimal effects to 0.02 acres of 

riparian vegetation at barrier site. Shortterm effects to 0.1 acre of previously disturbed vegetation at staging area. 

Long-term benselected stock 

Terrestrial Wildlife No effect. Short-term disturbance and possible 

incidental death at barrier and staging areas. Long-term improvement in riparian community at barrier site. Minor disturbance during other activities. Possible loss of public access to water at selected stock tanks. 

Minor disturbaPossible loss oselected stock 

Fish and Aquatic Wildlife Continued negative impacts to all 

aquatic wildlife from nonnatives. Potential for future invasion of additional nonnative species. Probably extirpation of longfin dace, speckled dace, and desert sucker and preclusion of their recovery in project area. Continued high risk from introduction and spread of nonnatives through stock tanks. 

Expansion of populations of five native fishes in scattered habitats throughout about 30 miles of stream channel. Stabilization or improvement of populations of canyon treefrog, black-necked gartersnake, Mexican gartersnake, and Sonora mud turtle. Mortality of some native fish, amphibians, and turtles from piscicide use. Protection of these populations against nonnative reinvasion. 

Expansion of pfishes throughostream channeimprovement otreefrog, blackMexican garterturtle. Mortaliamphibians, anuse. Protection against nonnat

Special Status Species Continued negative impacts to 

federally listed and sensitive aquatic wildlife from nonnatives. Potential for future invasion of additional nonnative species. Gila topminnow, Chiricahua leopard frog, and Sonora tiger salamander likely to be extirpated from Redrock Canyon. 

Implementation of recovery plan recommendations for three species. Shortterm adverse effects at barrier, including possible incidental take of Gila topminnow. Some mortality of all aquatic species because of piscicide use. Expansion of populations of Gila topminnow, Chiricahua leopard frog, and Sonora tiger salamander 

Partial implemrecommendatioSome mortality from piscicide populations of Chiricahua leosalamander pohabitats throug

Draft Environmental Assessment Native F
Gila chub is not restored to 

watershed. 

populations in appropriate habitats throughout watershed. Protection of these populations against nonnative reinvasion. . 

watershed. Propopulations ag

Cultural Resources No effect. No effect. No effect. Livestock Grazing No effect. No effect. No effect. Recreation and Visual Resources 

No effect. With the proposed mitigation, the project 

would have minimal effects to recreation and would meet Visual Quality Objectives. 

No effect. 

Soils No effect. Approximately 0.12 acres of alluvial soils 

affected during construction of the fish barrier. Post construction sediment deposition on 1,475 feet of channel unpstream of the barrier. Low impact from foot traffic associated with stream renovation 

Low impact frowith stream ren

Air Quality No effect. Highly localized minor effect during 

construction resulting from fugitive dust and engine emissions. 

No disturbance 

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
CHAPTER 3 – ENVIRONMENTAL CONSEQUENCES

This chapter presents the existing conditions in the project area and the environmental 

consequences that would result from no action and from implementation of either the 

proposed action or alternative A. The description of the affected environment and the 

impact analyses that follow are based on the best scientific information available. 

3.1 WATER RESOURCES

3.1.1 Affected Environment 

Average annual precipitation in the area of the project is 18 inches; however, daily 

precipitation is highly variable and can be greater than 4 inches (Sellers and Hill 1974). 

Precipitation is primarily rain, but some snow may occur at the higher elevations. The 

precipitation pattern is a bimodal monsoonal pattern, with winter storms originating in 

the northern Pacific Ocean and summer storms resulting from convective thunderstorms 

that form from moisture drawn into the region from the Gulf of Mexico and the Gulf of 

California. 

Hydrology and Geomorphology. Redrock Canyon is a major tributary of Sonoita Creek, 

comprising approximately 15% of the drainage area above the Sonoita Creek gaging 

station (USGS gage #09481500), which is located 8 miles downstream of Patagonia. 

There is no discharge gage in Redrock Canyon. The collection of daily stream flow data 

at the Sonoita Creek gage was discontinued in 1972, although peak flows were recorded 

at this gage in 1977 and 1983. Peak flow for the period of record11 was 16,000 cubic feet 

per second (cfs), recorded in October 1983. Mean annual discharge for the period of 

record was 8 cfs. Flood reoccurrence estimates are 3,130 cfs for a 2-year event, 7,190 cfs 

for a 10-year event, and 15,100 cfs for a 100-year event (Pope et al. 1998). 

The Redrock Canyon watershed is approximately 8 miles long and 5 miles wide 

(Figure 2). It is bounded on the north and east by the Canelo Hills, on the south by the 

Patagonia Mountains, and the north edge of the San Rafael escarpment. The expansive 

interior supports a moderately complex network of drainages among moderate to steeply 

sloping ridges. The mainstem of Redrock Canyon proper is approximately 12 miles in 

length. There are two major tributaries inflowing from the south: Cott Tank drainage, 

which is about 1.75 miles long, and the unnamed tributary containing Kennedy Spring, 

which is approximately 3 miles long. Two major northern tributaries originate on the 

slope of the Canelo Hills, then run on a northwest/southeast axis behind a subsidiary 

ridge of the Canelo crest before turning abruptly to drop through short bedrock canyons 

into the main basin. The most upstream of these is Lampshire Canyon, with about 4.5 

miles of mainstem and several tributaries, including Box Canyon, about 2.25 miles long. 

The second is Oak Grove Spring Canyon, with a mainstem of about 2.25 miles below the 

bedrock canyon and about 3 miles upstream in two main forks. Oak Grove Spring 

 

11 The period of record for gage #09481500 is 1930-1933, 1935-1972, 1977, and 1983. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 32
Canyon has two main tributaries downstream of the bedrock canyon, both unnamed, one 

about 2 miles in length and the other about 1.25 miles. 

Most of the stream channels within the Redrock watershed are of low to moderate 

gradient. In the reach of Redrock Canyon that includes the barrier, the gradient is 

approximately 0.6%. The stream channel in that location is a bedrock sill with a braided 

channel through coarse sediment (gravel, cobble, boulder) upstream (Figure 5). A few 

streamside terraces with deposited soils exist in this reach of Redrock Canyon, but most 

of the channel is spatially unstable and reestablishes a new channel with each significant 

flood event. 

Figure 5. Downstream view of proposed fish barrier site (photo courtesy of S.E. 

Stefferud). 

Water Quantity and Quality. Anecdotal information from local ranchers indicates that 

Redrock Canyon historically supported more surface water and perennial streamflow than 

at present. Draining of the large cienega at the confluence of Harshaw, Redrock, and 

Sonoita creeks in the mid-1800s likely contributed to depletion of surface water in 

Redrock Canyon and downcutting of the channel (Hendrickson and Minckley 1984; 

Davis 1986). Agricultural activity may have played a role in destabilization of the 

terraces, removal of riparian vegetation, channel erosion, and subsequent reduction of 

perennial flow. Perennial surface water is now restricted to a few isolated areas. The 

size of these areas has constricted considerably since the mid-1990s because of extended 

drought in the area. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 33
Over the past 15 years, perennial water has been found at Falls, Gate Spring, Cott Tank 

drainage, and Pig Camp Spring. As a result of increased bank storage in Cott Tank 

drainage following exclosure from livestock grazing in 1992, water is now perennially 

present in Redrock Canyon below its confluence with Cott Tank drainage. Surface water 

has usually also been present in the West Redrock Exclosure and in the springs/bedrock 

canyon area of Oak Grove Spring Canyon. After livestock were removed from the 

Kunde allotment in 1997, riparian vegetation developed along some reaches, and a new 

area of semi-perennial flow arose about 0.25 miles upstream of Redrock Ranch on the 

border of Sections 7 and 12 (Figure 2). By June 2001, there was 850 feet of surface flow, 

gradually diminishing to only 150 feet in October 2005 and disappearing by October 

2006. Surface water is also usually found at several springs within the watershed. 

The drought that began in the Southwest about 1995 has substantially reduced the amount 

of surface water in Redrock Canyon watershed. Some areas that had water year-round in 

the early 1990s may now occasionally be dry; and, where surface water persists, it is 

significantly reduced in extent. Despite good precipitation in 2000-2001, which 

prompted long periods of continuous flow through the mainstem, accumulating effects of 

the drought have resulted in loss of most of the water that supported native fish during the 

late 1970s to early 1990s when the majority of existing fish data were being gathered. 

The presence of native fish above barriers in Redrock Canyon and Cott Tank drainage 

indicates these areas have always retained enough surface water to support aquatic life 

even during earlier extended droughts, such as the late 1800s or the 1950s. 

In June 2006, significant surface water existed in Redrock Canyon only in a few stock 

tanks, in Cott Tank drainage, and in Redrock Canyon within the Cott Tank exclosure 

downstream of the confluence with Cott Tank drainage. Table 2 depicts water conditions 

in the stream in June 2006. Strong summer rains in July through September 2006 likely 

increased the presence of surface water to some extent; but, in general, summer 

precipitation does not result in long-term enhancement of base flows. 

Complex water systems have been constructed within the Redrock Canyon watershed to 

transport water long distances to service livestock. In addition to the 17 stock tanks, 

approximately 20 wells exist, although some may no longer be in use. Approximately 

15 miles of pipeline feed water to many troughs throughout the drainage. About half a 

dozen trick tanks capture water in various locations. Some water is imported into the 

Redrock Canyon watershed from wells in the Meadow Valley, Cienega Creek, and 

Babocomari watersheds to serve livestock troughs in upper Redrock Canyon, portions of 

Oak Grove Spring Canyon, and upper Box Canyons. The Forest Service reports that 

imported water all originates from groundwater with no contact with surface water 

outside of Redrock Canyon, thus eliminating any potential for transport of nonnative 

aquatic vertebrates (pers. comm., Bill Edwards, Coronado National Forest, Sierra Vista 

Ranger District, September 2006). 

Although the present scarcity of surface water is a major detriment to native fish and 

amphibians, it provides optimum conditions for removal of nonnative fishes. Reduced 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 34
volume of water and elimination of marshy areas substantially reduces the complexity of 

application of piscicides and other control methods. 

Table 2. Water conditions in Redrock Canyon stream and springs (excluding stock 

tanks), June 2006 (All data from unpub. data of J.A. & S.E. Stefferud, except as noted). 

AREA WATER 

PRESENT 2006 

TYPE/EXTENT OF WATER 

West Redrock Exclosure No Damp ground at barrier site 

Pig Camp Spring Yes 18-inches diameter 

<2-inches deep 

Redrock Canyon between West 

Redrock Exclosure and Falls 

Exclosure (inc. USFS named Redrock 

Spring 

No 

Falls Exclosure Yes At base of falls 

12 x 15 feet, 4-feet deep 

Redrock Canyon between Falls 

Exclosure and Gate Spring Exclosure 

No 

Gate Spring Exclosure Yes Only in salt spring perched on channel 

side near lower end of exclosure 

Redrock Canyon between Gate Spring 

Exclosure and Cott Tank Exclosure 

No 

Redrock Canyon in Cott Tank 

Exclosure 

Yes Two pools 

5x2 feet, 1-foot deep 

4x3 feet, 0.5-feet deep 

Redrock Canyon above junction with 

Cott Tank drainage 

No 

Cott Tank drainage below barrier Yes Five pools 

15x4 feet, 2-feet deep 

5x3 feet, 0.8-feet deep 

13x40 feet, 2.5-feet deep 

55x4 feet, 2-feet deep 

20x6 feet, 2.5-feet deep 

“Camp” Spring in side tributary to 

Cott Tank drainage (Sec. 21) 

Yes Wet marsh 40 x 3 feet 

Cott Tank drainage above barrier Yes Two pools 

2x3 feet, 0.5-feet deep 

15x10 feet, 1-foot deep plus 20 feet of 

marsh flow above and 34 feet of 

shallow open flow over bedrock below 

Unnamed tributary to Cott Tank 

drainage in Sec. 22 

Not surveyed June 2003 – flow 15-feet long, shallow 

Unnamed tributary to Redrock west of 

Oak Grove Spring Canyon (including 

USFS-named G&F Horizontal 

Well/Spring) 

Not surveyed June 2002 – pools <1% of area 

surveyed, ave. width 5 feet, ave. 

length 8.3 feet, ave depth, 5 inches 

(Mitchell 2002) 

Oak Grove Spring Canyon springs 

(including North and Southeast Forks 

and USFS-named Oak Spring) 

No 

Unnamed tributary to Oak Grove 

Spring Canyon in east 1⁄2 Sec. 35 

No Surveyed only up to bedrock and 

trough in lower end 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 35
Table 2 – Continued. 

AREA WATER 

PRESENT 2006 

TYPE/EXTENT OF WATER 

 Unnamed tributary to Oak Grove 

Spring Canyon in west 1⁄2 Sec. 35 

(including three springs – USFSnamed North and Richard Hale 

Springs and an unnamed spring) 

Not surveyed June 2003 --slight seepage at upper 

spring, pool 3x4 feet, 2-inches deep. 

Below barrier near mouth, 30 feet of 

orange water 2-4-inches deep 

Lampshire Canyon (including 

Cottonwood Spring) 

No 

Rock and Turtle Springs Not surveyed 

Spring in unnamed tributary to 

Redrock just east of Lampshire 

Canyon 

Not surveyed 

Box Canyon Not surveyed June 2003 – stagnant pool 4-feet 

diameter at small bedrock drop at 

about 4,900-foot elevation 

Kennedy Spring drainage (including 

Kennedy Spring) 

Not surveyed October 2002 – downstream about 1⁄2 

mile from unnamed tank in Sec. 21 

short areas of water up to 10 x 5 feet 

and 2-3-inches deep. At Kennedy 

Spring, flow 20-feet long up to 5- 

inches deep. 

The ADEQ sets narrative and numeric standards for water quality based on the uses 

people and wildlife make of the water. For Redrock Canyon, uses are classified as live 

aquatic life, warm water, full body contact, and fish consumption. The 2004 Integrated 

305(b) Water Quality Assessment and 303(d) Listing Report indicated that surface water 

in Redrock Canyon was in attainment of water quality standards for all designated uses. 

There are no streams in the project area that are either Congressionally designated as or 

eligible for Wild and Scenic River status (http://www.rivers.gov/wildriverslist.html#az). 

3.1.2 Environmental Consequences 

No Action 

Hydrology, geomorphology, and surface water quantity and quality would not change if 

no action is taken. 

Proposed Action

Direct and indirect impacts to water resources in the project area may result during 

barrier construction, barrier presence, and mechanical and chemical treatments to remove 

nonnative species. 

Waters of the U.S. The COE regulates discharges of fill material to waters of the U.S., 

pursuant to Section 404 of the CWA, and issues permits for actions proposed within such 

waters. Jurisdictional, non-tidal waters of the U.S. regulated by the COE are defined in 

33 CFR 328.4 (c) as those that comprise the area of a water course that extends up to the 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 36
ordinary high-water mark (OHWM), in the absence of wetlands. Based on Reclamation’s 

delineation of the OHWM, less than 0.01 acre of jurisdictional waters would be affected 

by the discharge of 55 cubic yards of fill material during construction of the concrete 

barrier. The fill material would consist of structural concrete, gabions or riprap, and 

excavated channel alluvium redeposited as backfill at the barrier. A COE 404 permit has 

been issued for barrier construction (see Chapter 5 for additional CWA information). 

Removal of nonnative species would have no impact on those attributes of jurisdictional 

waters of the U.S. regulated by the COE. 

Hydrology and Geomorphology. Shortly after completion, the constructed barrier 

would trap bedload material behind it, causing a zone of sediment deposition upstream 

(Figure 6). Aggradation of the streambed from sediment deposition would slightly flatten 

the channel gradient and permanently raise the water surface profile along a 1,475-foot 

segment of stream, affecting 1.4 acres of channel. The higher stream profile would be 

most noticeable where water overtops the barrier (i.e., where there is a 5-foot elevation 

change) and would disappear altogether upstream at the point where the aggraded zone 

converges with the normal level of the streambed. 

No long-term impact on sediment transport, siltation, or deposition patterns within the 

stream would occur. The raised water profile is expected to have a minimal erosive 

effect on the integrity of the channel banks, because they are armored with bedrock, 

boulders, and cobbles. Pool development on the upstream side of the barrier would be 

minimized to the maximum extent practicable by backfilling the area with surplus 

alluvium excavated to accommodate the barrier foundation and gabion trench. Bedload 

sediment that would be deposited during flooding and high seasonal flow is expected to 

displace any remaining pools within 2 to 3 years. 

Changes in channel morphology in the construction area would have minimal effects on 

flow and erosion patterns at the downstream toe of the barrier, because gabion or riprap 

bedding would be placed along the apron. 

Removal of nonnative species by chemical and mechanical treatments would have no 

impact on hydrology or geomorphology. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 37
Figure 6. Post-construction sediment deposition upstream of the barrier. 

Water Quantity and Quality. Construction of the barrier would have a negligible effect 

on surface and subsurface flows. The reach of stream encompassing the barrier site is on 

a shallow bedrock sill that forces groundwater to the surface, so any subsurface flow that 

might be cut off by the barrier foundation would become surface flow that spills over the 

top of the structure. In addition, the barrier foundation would be situated on an alluvial 

base above this sill, allowing a portion of the subsurface flow to pass under the structure. 

At the barrier site, a greater quantity of subsurface water is likely to be retained in the 

stored sediments behind the barrier than at present. However, once this sediment is 

saturated, the volume of surface and subsurface water conveyed downstream beyond the 

barrier would approximate pre-construction conditions. 

Barrier construction is planned to occur during the dry season. If atypical heavy 

precipitation should occur, there is a potential for runoff to transport fine sediment into 

the stream and increase its turbidity. In this location, however, the amount of fine 

sediment is minimal because of the coarse substrate of the floodplain (Figure 5). Further, 

floodwaters in this reach tend to be quite turbid anyway because of upstream channel 

instability. Therefore, no substantial change in the stream’s turbidity is anticipated if 

runoff were to occur during barrier construction. 

Pumping of stock tanks and possibly cienega pools to facilitate nonnative removal may 

affect surface water availability in the short term. Water removed from tanks and pools 

would be spread onto adjacent terraces and hillsides and would not be placed into the 

stream channel due to the risk of spreading nonnative species. Water availability for 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 38
livestock would be affected if livestock are present during or shortly after pumping. In 

that case, effects would be mitigated by providing alternative sources of water for 

livestock use. Water availability for terrestrial wildlife would be adversely affected for 

the short-term. Current below-normal precipitation patterns provide insufficient runoff 

and base flow to keep most tanks and in-channel pools filled. Water removed by 

pumping may not be replaced for weeks or months depending on weather conditions. 

This could impact native fish restoration following nonnative removal. To avoid this, 

stock tanks and in-channel pools would not be pumped dry unless it is the only means 

available to ensure total eradication of nonnative fish and/or bullfrogs. 

Effects to water quality from application of piscicides and neutralization compounds 

would be short term and restricted to the project area (see Appendix E). Piscicides would 

not be applied during periods of precipitation and runoff to avoid downstream water 

quality impacts. If, however, unexpected heavy precipitation and runoff occur after

application has begun, piscicide in the downstream flow from the project area would 

detoxify rapidly because of dilution in floodwaters and the effects of turbulence, 

sediment, and organic material (Schnick 1974; Dawson et al. 1991; Lee et al. 1971). In 

the event of any potential movement of toxic amounts of piscicides downstream of the 

project area, detoxification with potassium or sodium permanganate would be undertaken 

at the constructed barrier site. 

Alternative A

If Alternative A is implemented, the impacts to hydrology, geomorphology, groundwater, 

and water quality and quantity reported for the Proposed Action would not occur. 

Impacts to water quality from nonnative species removal (chemical and mechanical 

treatments) would occur over a smaller project area, because the area that would be 

treated under Alternative A comprises approximately 23 miles of stream channel in the 

mainstem and major tributaries, which is about 7 miles less than the area that would be 

treated under the Proposed Action. 

Cumulative Effects – Water Resources

Sources of cumulative effects to water resources in the project area include historic 

human activities such as road construction, use of the area by undocumented immigrants, 

wildland fire, and livestock grazing. 

Erosion remains a concern within the watershed, and the Forest Service has undertaken 

several projects to control specific sites of channel erosion. Neither action alternative 

includes plans for construction of additional roads nor would either be expected to 

substantially increase erosion or sediment production within the Redrock Canyon 

watershed. 

Transitory use of the Redrock Canyon watershed by undocumented immigrants has 

created many user-built trails, where foot-traffic contributes to erosion and increases the 

probability of wildand fire occurrence because of unextinguished or uncontrolled 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 39
campfires and signal fires. Wildland fire increases erosion, and subsequent runoff carries 

sediment and toxic ash into surface waters. The duration and extent of these effects are 

dependent on the size of the fire and the quantity and type of vegetation that burns. 

Historic use of the watershed for grazing has reduced cover and destabilized soils, which 

contributed to sedimentation and adverse water quality effects. Current grazing 

management practices (see Section 3.4) have improved range conditions and reduced 

impacts to water quality. 

Neither of the action alternatives would contribute cumulative, long-term effects to water 

resources. 

3.2 BIOLOGICAL RESOURCES 

3.2.1 Affected Environment -- Vegetation 

Following is a general discussion of vegetation in the project area. Vegetation that 

comprises Forest Service-designated sensitive plant species in the Redrock Canyon 

watershed is addressed in Sections 3.2.7 and 3.2.9. 

Redrock Canyon lies in the upper Sonoran life zone (Lowe 1964). Dominant vegetation 

types are broadleaf woodland (evergreen), with an overstory of Madrean oaks, 

predominantly Emory, Mexican blue, and Arizona white (Quercus emoryi, Q. 

oblongifolia, and Q. arizonica), and alligator juniper (Juniperus deppeana). Semi-desert 

grassland (Brown 1994) is also present in the watershed, with mesquite (Prosopis 

velutina) and catclaw acacia (Acacia greggii) the predominant overstory species and 

curly mesquite (Hilaria belangeri), gramma grasses (Bouteloua spp.), and lovegrass 

(Eragrostis spp.) the common understory species (USFS 2003). 

Riparian vegetation is found discontinuously along Redrock Canyon proper and many of 

its tributaries (Danzer et al. 2001; Stefferud and Stefferud 2004). Well-developed 

riparian areas are found primarily within livestock exclosures, although they have also 

developed in the central portion on the Kunde allotment, which has not been grazed 

under permit since 1996. Fremont cottonwood (Populus fremontii) and Goodding and 

yew-leaf willow (Salix gooddingii and S. taxifolia) are a major component of these 

riparian areas, with an understory of deergrass (Muhlenbergia rigens), seepwillow 

(Baccharis salicifolia), and a variety of sedges (Carex spp.) and rushes (Juncus spp.). 

Outside of these areas, Arizona ash (Fraxinus velutina), Arizona walnut (Juglans major), 

and Arizona sycamore (Plantanus wrightii) are the primary tree species, with an 

understory of seepwillow, deergrass, and upland grasses. Small areas of mesquite bosque 

and sacaton (Sporobolus wrightii) are present on terraces. 

In the stream channel, submergent and emergent vegetation in areas of surface flow 

includes a variety of algae, duckweed (Lemna minor), cattails (Typha latifolia), and 

spike-rushes (Eleocharis spp.). Nonnative vegetation in the riparian area includes tree of 

heaven (Ailanthus altissima), tamarisk (Tamarix pentandra), Johnson grass (Sorghum 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 40
halepense), rabbit-foot grass (Polypogon monseliensis), Bermuda grass (Cynodon 

dactylon), and watercress (Rorippa nasturtium-aquaticum). 

3.2.2 Environmental Consequences -- Vegetation 

No Action 

If no action is taken, vegetation would not be impacted. 

Proposed Action 

Sources of potential impact to vegetation include clearing of areas for a staging area and 

for fish barrier construction and introduction of nonnative plant seeds on vehicles and 

heavy equipment. 

A staging area less than 0.1 acre in size would be located alongside FSR 138. Ground 

cover is sparse except during late summer, when annual grasses and forbs appear after 

monsoon precipitation. Vegetation that would be cleared or otherwise disturbed includes 

shrubs and herbaceous plants. The staging site has been disturbed repeatedly over many 

years by road maintenance, dispersed recreational camping, livestock grazing, and offroad vehicle travel. Impacts to vegetation from clearing during barrier construction are 

considered minimal because of the small area that would be disturbed, the type of 

vegetation present in that area (i.e., mostly seepwillow and scattered mesquite), and the 

high probability for regrowth of the area in a short period of time after the barrier is 

constructed. 

Most of the proposed barrier construction site is unvegetated sand, gravel, and cobble 

(Figure 5). Vehicle trips into the construction area would be infrequent, and off-road 

travel would mostly be limited to the usually dry streambed between the FSR 138 lowwater crossing and the barrier site. An estimated 0.02 acres of vegetation would be 

disturbed along a pre-existing vehicle corridor from FSR 138 upstream to the barrier site. 

Removal or trimming of seepwillow and deergrass may be required to allow construction 

vehicle access. These riparian species are both adapted to periodic disturbance and grow 

back rapidly from the ground level. 

Vehicles and heavy equipment would be powersprayed before entering the construction 

site to lower the risk of nonnative plant spread. 

No disturbance of riparian or upland vegetation would occur during removal of nonnative 

fauna and native species restoration. Effects to aquatic vegetation would be localized and 

minimal. Aquatic vegetation may be removed during salvage and piscicide treatment to 

allow for adequate distribution of the chemicals. Emergent vegetation, such as cattails, 

may be cut off below the water line but would grow back quickly after treatment. 

Duckweed may be scraped from the ponds and watercress from streams and springs to 

allow access to the water but would quickly recover following treatment. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 41
Alternative A

Effects to vegetation under Alternative A would be similar to those described for the 

Proposed Action but without effects of barrier construction. Localized and ephemeral 

effects would occur to aquatic vegetation during salvage and piscicide application. 

Cumulative Effects - Vegetation

Effects to vegetation are ongoing from other human activities in the area. Impacts to 

vegetation from livestock grazing in the watershed have been fully explored in the EA 

completed by the Forest Service on livestock management (USFS 2003). 

Incremental effects on vegetation from either action alternative would be discountable. 

Vehicle use inside the West Redrock Exclosure at the proposed barrier site has the 

potential to cause a short-term interruption in the recovery of the riparian area that has 

developed since the exclosure was created in 2002. 

3.2.3 Affected Environment -- Terrestrial Wildlife 

Redrock Canyon provides a corridor for wildlife movement between Sonoita Creek and 

Canelo Hills. A wide variety of wildlife occupies the watershed. Habitat diversity is 

provided by high-elevation oak woodlands to low-elevation desert grasslands. The 

presence of surface water and riparian vegetation support a diversity and abundance of 

species that would not otherwise be found in these arid lands. 

This section discusses terrestrial wildlife in the Redrock Canyon watershed. Ten 

federally listed species are considered in Section 3.2.7. Twenty-one animal species on 

the Forest Service’s Region 3 sensitive species list and 13 on the CNF list of 

Management Indicator Species (MIS) are considered in Section 3.2.9. 

3.2.4 Environmental Consequences -- Terrestrial Wildlife

No Action

If no action is taken, terrestrial wildlife would not be impacted. 

Proposed Action

Terrestrial wildlife in the immediate vicinity of the barrier and staging area would be 

disturbed in the short-term by vehicle and equipment activity and human presence. 

Direct injury or mortality of slow-moving animals may occur during vehicle or 

equipment operation. Losses are expected to be minimal, as most species would be 

temporarily displaced from the area shortly after the onset of construction. 

Temporary noise and habitat disturbance would occur in both areas. In the long-term, the 

barrier is expected to locally improve the quality of riparian habitat by creating a small 

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Native Fish Restoration in Redrock Canyon 42
area of fine-sediment deposition and water retention upstream, which would encourage a 

denser growth of riparian vegetation. The fish barrier is not expected to prevent 

movement of terrestrial species. Side slopes in the area are sufficient to allow terrestrial 

wildlife to easily move around the barrier. 

Removal and restocking of native aquatic wildlife would not affect terrestrial wildlife. 

Movement of project personnel throughout the canyon could result in a few days of 

disturbance of wildlife. 

During piscicide application, terrestrial wildlife may drink or have body contact with 

waters containing rotenone or antimycin A and may consume fish killed by the piscicide. 

Terrestrial vertebrates do not uptake either of the piscicides through body contact, and 

neither piscicide is toxic to vertebrate animals when applied at levels and formulations in 

accordance with the labels. The effects of rotenone and antimycin A on terrestrial 

vertebrates are reported in detail in Appendix E. 

Cattle, which may be in the watershed during the project, are not expected to be affected 

by either piscicide. Rotenone was used as a control for grub on dairy and beef cattle for 

many years with no adverse effects, and the EPA has reported that there is no need to 

restrict livestock consumption of treated waters (Finlayson et al. 2000). However, 

alternative water sources for livestock would be provided, as necessary, to prevent 

disruption of cattle access to water or to draw cattle away from areas where their 

presence may disrupt project implementation. 

Alternative A

 

Implementation of Alternative A would have minimal effects on terrestrial wildlife, 

which would be similar to those of the Proposed Action. Effects at the barrier site from 

construction and vehicle traffic would not occur. Minor, temporary, and localized 

disturbance of terrestrial species may result from nonnative removal and native 

restocking operations. No effect from piscicide application would result (see Proposed 

Action). 

Cumulative Effects – Terrestrial Wildlife

Historical and ongoing livestock operations within the Redrock Canyon watershed have 

previously impacted terrestrial wildlife as a result of changes in vegetation and forage 

availability, roads, and water development. Recreation in the watershed is light, with 

some hunting and minimal effects to terrestrial wildlife. Activities associated with 

undocumented migration and efforts at its control have increased human activity within 

the watershed. Neither of the two action alternatives would incrementally contribute to 

these cumulative effects. 

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Native Fish Restoration in Redrock Canyon 43
3.2.5 Affected Environment -- Fish and Aquatic Wildlife 

Redrock Canyon historically supported a diverse aquatic vertebrate fauna, including the 

five species of fish proposed for restoration12, Chiricahua leopard frog, canyon treefrog, 

Sonora tiger salamander, Sonora mud turtle, black-necked gartersnake, and possibly 

Mexican gartersnake (Appendix A). Two federally listed fish (Gila topminnow and Gila 

chub), the leopard frog, and the salamander are discussed in Section 3.2.7. The desert 

sucker is a Forest Service-sensitive species (FSS), but is discussed here because of the 

similarity of effects with longfin and speckled dace. The other species to be discussed in 

this section include longfin dace, speckled dace, canyon tree frog, Sonora mud turtle, and 

black-necked and Mexican gartersnakes. Aquatic invertebrate fauna exist in Redrock 

Canyon surface waters; however, little is known about the individual species of that 

assemblage. No rare aquatic invertebrates are known from the Redrock Canyon 

watershed (see discussion of Huachuca springsnail in Section 3.2.7). 

Longfin dace. Until the mid-1990s, longfin dace were common throughout the mainstem 

of Redrock Canyon from above Camp Spring downstream to below the Forest Service 

boundary, and in Lampshire Canyon below Lampshire Dam and in the lower half of Oak 

Grove Spring Canyon and its two main tributaries (Stefferud unpub. data). Their 

abundance and distribution expanded and contracted according to seasonal and annual 

water conditions. They were the only fish regularly occupying open areas of temporally 

intermittent flow (Figure 7). By 1994, they had disappeared from the watershed 

upstream of Gate Spring, by 2001 they disappeared from the reach between the Falls and 

Gate Spring, and the last longfin dace below the Falls was recorded in 2003 (Appendix 

A). The reason for their disappearance is unsubstantiated but is likely related to the 

adverse effects of nonnatives and to the gradual drying of the stream channels in the 

watershed. 

By 2003, the drought had dried major areas that had supported longfin dace. Although 

water was still present most of the time at Gate Spring, there are now periods of no water. 

In the Cott Tank exclosure, while water still exists, it is isolated in pools, which are not 

preferred habitat for longfin dace and are occupied by mosquitofish. Stream areas 

between pools that existed prior to 1996 are now totally dry. Mosquitofish are thought to 

have little effect on longfin dace under normal conditions. Longfin dace are usually 

found in relatively fast, shallow water on riffles and runs, whereas mosquitofish cannot 

maintain in fast current and prefer pools, stream margins, and backwaters. However, 

when pushed by drought into the remaining pools, mosquitofish may have a substantial 

negative effect on longfin dace survival. Longfin dace are still common in Sonoita Creek 

downstream of Patagonia (Foster and Mitchell 2005; Killeen 2005) and in Harshaw 

Creek (Stefferud and Stefferud 2004). 

 

12 Gila topminnow, longfin dace, speckled dace, desert sucker, and Gila chub 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 44
Figure 7. Longfin dace habitat in temporally intermittent flows, June 2001 (photo 

courtesy of J.A. Stefferud). 

Speckled dace. Speckled dace have occurred for decades in Sonoita Creek near its 

junction with Redrock Canyon (Minckley 1969). Although it was once a common 

species throughout the Gila River basin and remains relatively widespread in the northern 

part of the basin, only this small speckled dace population remains in the southern part of 

the basin (Desert Fishes Team 2004). 

Speckled dace prefer fast water and coarse substrates and are most often found in riffles. 

No early records of speckled dace exist in Redrock Canyon; the first record did not occur 

until the 1970s. By that time, substantial anthropogenic changes had occurred in the 

Redrock Canyon watershed, and the availability of water and suitable habitat had likely 

changed dramatically. In November 2001, following good summer rains, speckled dace 

was found occupying Redrock Canyon in the vicinity of the proposed barrier site 

(Stefferud and Stefferud 2004). Despite sampling, no additional sightings of speckled 

dace have occurred in Redrock Canyon. It is presumed speckled dace move upstream 

from adjacent Sonoita Creek during periods of strong flow, such as in 2001. 

Desert sucker. Desert sucker are periodically found in Redrock Canyon below the Falls. 

They apparently move upstream from Sonoita Creek during times of good surface water 

flow but, despite the presence of suitable water upstream, cannot move beyond the barrier 

presented by the Falls. Records are from 1987, 2001, and 2002, but this lower reach was 

seldom sampled prior to 1999 (Simons 1987a; AGFD files; Stefferud unpub. data). 

Desert sucker is one of the most persistent native fish species in the Gila River basin, but 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 45
populations are declining throughout its range (Desert Fishes Team 2004). They are able 

to use small waters and a rather wide range of habitat types but require at least some riffle 

or run habitat in which to reproduce (Minckley 1973). 

Canyon tree frog. Based on incidental sightings during fish sampling, canyon tree frog is 

common in the lower portion of Redrock Canyon, including Oak Grove Spring Canyon 

(Stefferud unpub. data). However, given its nocturnal nature and the presence of suitable 

habitat, it is likely that the species is found at water sources throughout the watershed. 

Tadpoles are aquatic herbivores, while adults feed on small invertebrates, both aquatic 

and terrestrial. 

Sonora mud turtle. The Sonora mud turtle is an opportunistic predator that prefers pools 

and slow-moving waters. It is found throughout Redrock Canyon. It is common within 

the Cott Tank exclosure and has been seen at Gate Spring, Falls, several miles upstream 

in Lampshire Canyon, in tributaries of Oak Grove Spring Canyon above the springs, and 

in Down Under and Martin Tanks (Stefferud unpub. data; Mitchell 2002). Given that 

most surveys have been by biologists looking for fish, only a small proportion of mud 

turtles observations are likely recorded. 

Black-necked gartersnake. The black-necked gartersnake has been observed at Gate 

Spring, near Red Bank Well, and there was a probable sighting in upper Lampshire 

Canyon (Stefferud unpub. data). These records were taken during fish surveys, and other 

records of the species in the watershed may exist. Black-necked gartersnakes feed 

primarily on frogs. 

 

Mexican gartersnake. In September 2006, in response to a petition requesting Federal 

listing of the northern subspecies of Mexican gartersnake (T. e. megalops), the FWS 

concluded that listing was not warranted because of uncertainty regarding its status in 

Mexico. The finding concluded that the subspecies has been extirpated in 85-90% of its 

historical range in the United States. 

The Mexican gartersnake is a riparian obligate species and uses cienegas, stock tanks, 

rivers, streams, and springs. It preys on frogs (both tadpoles and adults), native fish, and 

occasionally lizards, mice, and invertebrates (Rosen and Schwalbe 1988). The presence 

of native anurans and fish appears to be necessary to support Mexican gartersnake. Many 

nonnative fish in Arizona have spines in their fin rays, making them unsuitable prey for 

Mexican gartersnakes (Holycross et al. 2006). Predation by nonnative fish, bullfrogs, and 

crayfish is a major cause of the substantial declines that have occurred in the distribution 

and abundance of Mexican gartersnake (Fernandez and Rosen 1996; Degenhardt et al. 

1996; Rosen et al. 2001; Holycross et al. 2006). 

There are no verified records of Mexican gartersnake in the Redrock Canyon watershed. 

Mexican garter snakes are extant in O’Donnell Creek and the San Rafael Valley and were 

formerly in Bog Hole, only 2 miles from Cott Tank drainage. Habitat appears to exist for 

Mexican gartersnake in Redrock Canyon. While much of the drainage is drier and 

rockier than preferred by Mexican gartersnake, the cienega habitat in the Cott Tank 

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Native Fish Restoration in Redrock Canyon 46
exclosure appears to offer suitable habitat. Developing herbaceous cover within the Gate 

Spring exclosure may also provide suitable habitat, but the failure of perennial surface 

water and consequent loss of fish and frog prey in recent years may prevent its use by 

gartersnakes. 

Nonnative Species. Five nonnative aquatic species are known to have invaded Redrock 

Canyon: largemouth bass, green sunfish, bluegill, mosquitofish, and bullfrogs. The 

adverse effects of these species have already been discussed in Section 1.2, and the date 

of their most recent occurrence in areas of Redrock Canyon and their distribution are 

shown in Appendix A (Table A-1 and Figures A-1 to A-3). Removal of these species has 

long been discussed among biologists and agencies with interest in Redrock Canyon. A 

mechanical removal of largemouth bass in Cott Tank drainage was carried out in 1989 

but did not succeed in eradicating that species from the area. 

Stefferud and Stefferud (1994) discussed the potential to use piscicides for mosquitofish 

removal. They cited Desert Fishes Recovery Team deliberations concluding that 

mosquitofish removal attempts should not be made as long as survey data showed Gila 

topminnow continuing to be more predominant than mosquitofish, but that if data showed 

mosquitofish gaining dominance, then steps should be taken to immediately remove the 

mosquitofish. Data from the Stefferud autumn surveys show mosquitofish gaining 

dominance in 2002 (Figure 8). In 2000 and 2001, mosquitofish made up only three and 

13% of fish sampled. In 2002, they comprised 66%, rising to 97% by 2005. 

The largemouth bass is an aggressive predator; adults feed almost exclusively on fish, 

tadpoles, and crayfish (Moyle 2002). It has been shown to prey on native Gila basin 

fishes with adverse impacts to their populations and may completely extirpate some 

natives in small habitats (Minckley 1969; Minckley et al. 2002; Bonar et al. 2004). 

Largemouth bass is primarily a species of ponds and slower waters, which limits its 

potential distribution within Redrock Canyon (Appendix 3, Figure A-3). Cienega pool 

systems present in the Cott Tank drainage provide suitable habitat for largemouth bass. 

In addition to populations in stock tanks, largemouth bass established a reproducing 

population within the Cott Tank drainage during the late 1980s and early 1990s, declining 

only as the pools shrank with the onset of drought. 

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Native Fish Restoration in Redrock Canyon 47
0

250

500

750

1000

1988 1992 1996 2000 2004

Year

Total abundance 

Topminnow

Mosquitofish

Figure 8. Gila topminnow and mosquitofish relative abundance in Redrock Canyon 

1988-2005 (Stefferud and Stefferud 1994 and unpub. data). 

Green sunfish and bluegill records are limited to Redrock Canyon and Cott Tank 

drainage from Down Under and Cott tanks downstream to just beyond the confluence of 

the two channels (Appendix A, Table A-1 and Figure A-3). These two species are 

aggressive invaders in the Gila River basin and are well adapted to small waters. They 

easily establish reproducing populations, even in spatially intermittent streams such as 

Redrock Canyon (Capone and Kushlan 1991). Green sunfish and bluegill are 

opportunistic predators, consuming eggs, larvae, and small adult fish, as well as frog eggs 

and tadpoles and salamander eggs and young, with adverse effects to native fish, frog, 

and salamander populations (Lemly 1985; Rosen et al. 1995; Dudley and Matter 2000). 

The presence of these two sunfishes may have contributed to establishment of the 

nonnative bullfrog population. Bullfrog invasion has been shown to be facilitated by the 

presence of bluegill, through the reduction of predation on bullfrog tadpoles by predatory 

macroinvertebrates (Adams et al. 2003). Because of the substantial similarities between 

bluegill and sunfish food habits, it likely that green sunfish may play the same role in 

bullfrog invasion. Green sunfish and bluegill have been recorded in Redrock Canyon 

only in the upper end, including both the Redrock Canyon proper and Cott Tank 

drainages. 

Although a small-bodied species, mosquitofish has been implicated in declines of many 

native fish and amphibians (Grubb 1972; Casterlin and Reynolds 1977; Courtenay and 

Meffe 1989). They are highly aggressive, preying on fish eggs and larvae in addition to 

invertebrate foods. They are effective predators even in heavily vegetated and shallow 

areas that otherwise act as safe harbors from larger predators (Baber and Babbitt 2004). 

Mosquitofish also harass and nip individuals larger than themselves, leading to damage, 

disease, exhaustion, and death (Hurlbert et al. 1972; Fuller et al. 1999; Lawler et al. 

1999). This behavior may also result in non-lethal interactions that have signficant longDraft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 48
term adverse consequences to the harassed individuals and populations (Lima 1998). In 

Redrock Canyon, Gila topminnows show a high incidence of fin damage when 

mosquitofish are present (Dean 1987). Snyder (2006) found that although Sonora tiger 

salamander can persist in the presence of mosquitofish, they cannot establish a population 

where mosquitofish are present. Mosquitofish may also present substantial competition 

to native species, particularly during times of severe habitat constriction (Meffe 1983) 

such as the present drought. Mosquitofish are abundant in the Cott Tank livestock 

exclosure and readily colonize other areas of the canyon when surface waters are present. 

They have been recorded widely throughout the watershed (Appendix A, Table A-1 and 

Figure A-2). 

Bullfrogs are predatory in both tadpole and adult stages and reach high densities in 

southwestern waters (Kane et al. 1992; Rosen and Schwalbe 1995; Mueller et al. 2006). 

Bullfrog tadpoles are also known to produce chemicals that inhibit growth in tadpoles of 

other species and inhibit reproduction in guppies (Poecilia reticulata), a live-bearer 

similar to Gila topminnow (Boyd 1975; Kupferberg 1997). They have been implicated in 

the decline of several native fish and amphibian species (Lawler et al. 1999; Rosen and 

Schwalbe 2002; Bradford et al. 2004). Bullfrogs need permanent water but can migrate 

long distances over dry land to find a new water source, and it is not unusual to find them 

occupying small areas of isolated water. They have been present in Redrock Canyon 

since at least 1988 but did not become abundant until mid-1990s. Their spread appears to 

be associated with stock tanks in the drainage, and at least five tanks in the drainage have 

been recorded to support bullfrogs (Appendix A, Table A-1 and Figure A-1). Bullfrogs 

are common to abundant in Cott Tank drainage and at some of the stock tanks. Records 

from elsewhere in the basin are sporadic. 

3.2.6 Environmental Consequences -- Fish and Aquatic Wildlife 

No Action 

If no action is taken, nonnative aquatic species in the Redrock Canyon watershed would 

likely continue to expand in distribution and quantity, which may result in the extirpation 

of most native aquatic species. Although persistent drought will cause populations of all 

aquatic species to remain low until it subsides, it is not expected to eliminate 

mosquitofish or bullfrogs. Green sunfish and bluegill, if still present in the basin, may 

survive extended drought. Only largemouth bass, if still present, could likely to be 

eliminated by drought conditions because of its requirement for relatively large pools. 

Neither adult longfin nor speckled dace are believed to be particularly susceptible to 

mosquitofish predation and harassment or adverse impacts from bullfrogs because of 

differences in preferred habitat use. Adult desert suckers are often found in pools where 

sunfishes, largemouth bass, mosquitofish, and bullfrogs congregate. While predation by 

sunfishes and bullfrogs may be limited to eggs, larvae, and juvenile suckers, even large 

adults may be harassed and killed by relentless biting by mosquitofish (Baber and Babbitt 

2004). Larval stages of both daces and desert sucker use backwater and vegetated stream 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 49
edge habitats extensively where they are preyed upon by mosquitofish, sunfish, and 

perhaps bullfrogs. 

A significant portion of the habitat for these three fish species is located downstream of 

the natural barrier at the Falls. Without a constructed barrier, there is no mechanism to 

prevent future invasion of lower Redrock Canyon (including Oak Grove Spring Canyon) 

by additional nonnative aquatic species. 

Without human intervention, longfin and speckled dace and desert sucker cannot move 

into the large portion of the Redrock Canyon watershed above the Falls nor to areas of 

Oak Grove Spring Canyon above its natural barriers. If no action is taken, these species 

would be limited to that portion of Redrock Canyon below the Falls and lower Oak 

Grove Spring Canyon. This limited range increases their vulnerability to predation, 

drought, fire, and other negative factors. 

Under the no action alternative, longfin dace will continue to decline and perhaps become 

extirpated in Redrock Canyon as a self-sustaining population. Below the Falls, longfin 

dace, speckled dace, and desert sucker may be able to retain a periodic colonization 

pattern from Sonoita Creek but will not be able to expand their occupation of Redrock 

Canyon nor establish self-sustaining populations there. 

With no action, ongoing predation of canyon tree frog, black-necked gartersnake, and 

Sonora mud turtle by nonnative fish and bullfrogs would continue. However, adult 

populations of the Sonora mud turtle should not be impacted to a great extent because of 

its size and shell (van Loben Sels et al. 1994). Bullfrogs, as well as nonnative fishes, 

may compete for food resources of all three native herptiles (reptiles or amphibians). 

With the limited amount of surface water in the Redrock Canyon watershed, the prey 

base of fish, frogs, and aquatic invertebrates is limited. A large predator like largemouth 

bass or a small but abundant predator like mosquitofish may usurp food resources of 

other organisms. Bullfrog tadpoles are unpalatable to many fish, giving them a 

competitive advantage over native leopard frog tadpoles (Kruse and Francis 1977). 

Proposed Action

The Proposed Action would be beneficial to longfin and speckled dace, desert sucker, 

canyon treefrog, black-necked and Mexican gartersnake, and Sonora mud turtle. The 

three fish species would be restored into Redrock Canyon, and, with removal of predation 

by mosquitofish and reduced predation from bullfrogs, the three repatriated species could 

be expected to expand into all suitable areas and establish self-sustaining populations. 

The tree frog, gartersnake, and mud turtle would be released from predation and 

competition by nonnative aquatic species, allowing their populations to potentially 

expand in numbers and distribution within the watershed. Mexican gartersnake would 

also be restored to the watershed through salvage and/or stocking. 

 

The fish barrier particularly would benefit longfin and speckled daces and desert sucker. 

Longfin dace is now restricted to the 1.5-mile reach below the natural barrier at the Falls 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 50
and about 2.5 miles of the lower portion of Oak Grove Spring Canyon below the barriers 

on its mainstem and tributaries. The only records of speckled dace and desert sucker 

from Redrock canyon are in this lower reach of mainstem Redrock. Confinement to this 

small, intermittently flowing area makes both species vulnerable to any incursion by 

additional species of nonnatives, such as yellow bullhead (Ameiurus natalis) which are 

found downstream in Sonoita Creek (Killeen 2005). The construction of the proposed 

fish barrier would prevent such future invasions and would permit the removal of existing 

nonnatives in the area. The Proposed Action would assist in re-establishing longfin and 

speckled daces and desert sucker upstream of the Falls, providing them with the 

opportunity to establish larger, more widely distributed populations, thus making them 

less vulnerable to threats from all sources. 

The constructed fish barrier would work in conjunction with existing natural barriers 

within the canyon to achieve the benefits of a multiple-barrier system. Multiple-barrier 

systems confer advantages in controlling possible future nonnative incursions and are 

recommended (Carpenter and Terrell 2006). Only one natural barrier, the Falls, exists in 

the central portion of Redrock Canyon (Figure 4), approximately 1.5 miles upstream of 

the barrier site in the Proposed Action. Other natural barriers exist in the upper reaches 

of most of the tributaries but, because of their headwater locations, only a few are useful 

as parts of a multi-barrier system for the watershed as a whole. Constructed barriers also 

exist in at least two locations: Lampshire Dam and an old cement dam downstream of 

Down Under Tank. All stock tanks form barriers, but none have known habitat upstream 

for aquatic fauna. 

 

Placing a fish barrier in lower Redrock Canyon also has the potential to adversely impact 

native fish and other aquatic species. Loss of gene flow, inbreeding, and fragmentation 

are all possible adverse effects of barriers to fish movement (Sloat 1999). However, the 

species that occupy Redrock Canyon have already undergone substantial fragmentation 

and blockage of genetic exchange, and the addition of a constructed barrier would not 

add substantially to this blockage. 

Although it may not have existed as a barrier prior to downcutting in the late 1800s or 

early 1900s, the present barrier at the Falls effectively prevents any upstream gene flow 

in fish populations in Redrock Canyon. Genetic information indicates that Gila 

topminnow in Redrock Canyon are a part of the larger Sonoita Creek management unit 

but show small variations that indicate some degree of fragmentation, both between 

Redrock Canyon and Sonoita Creek and between Falls and Cott Tank drainage (Hedrick 

et al. 2001). If at a future time, enhanced genetic interchange is deemed desirable, it can 

be accomplished by periodically moving individuals from the five native fish species 

from the downstream segment of Redrock Canyon into upper segments (Waite et al. 

2005). 

Another potential adverse effect of a constructed barrier is the possible loss of larvae of 

native fishes through downstream drift over the barrier. Any larvae that did drift over the 

barrier would be unable to return upstream and would likely die as the reach of stream 

below the barrier regularly becomes dry. It is unlikely that downstream drift of larvae 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 51
below the barrier site has played any significant role in survival of the native fish of 

Redrock Canyon since the loss of the cienega at Patagonia in the late 1890s. The portion 

of the stream downstream of the proposed barrier site is dry most of the year; and, rather 

than moving back upstream, it appears that fish in that stretch tend to become isolated in 

pools which eventually dry resulting in their loss. 

Removal of nonnatives and prevention of downstream reinvasion and new invasions 

would benefit all aquatic wildlife. Nonnative predation effects to canyon tree frog, blacknecked and Mexican gartersnakes, and Sonora mud turtle were discussed earlier. While 

that discussion refers to the adverse effects of continuation of nonnative predation, under 

the Proposed Action, the effects would be reversed. Release from nonnative predation 

would benefit all three species, likely allowing them to expand their numbers and 

distribution within Redrock Canyon watershed. 

Some loss of gill-breathing nonnative aquatic wildlife would occur as a result of the use 

of piscicides in the surface waters of the Redrock Canyon watershed. All fish not 

salvaged would be killed by the piscicide. However, the restocking of salvaged fish 

following nonnative removal, with possible augmentation stocking from captive or 

nearest-neighbor stocks, is expected to result in increased abundance and distribution of 

longfin and speckled dace and desert sucker, for a long-term gain for both species. 

Little data exists on effects of the piscicides to amphibians. Lesser (1970) found that 

antimycin was not toxic to northern leopard frog tadpoles in fish-killing concentrations. 

Rotenone, however, is toxic to northern and southern leopard frog tadpoles at piscicide 

application levels (Hamilton 1941, as reported in Fontenot et al. 1994; Chandler and 

Marking 1982, as reported in Fontenot et al. 1994; Burress 1982). Adult leopard frogs 

were much less sensitive. It is likely that the proposed application of rotenone may result 

in some mortality of canyon tree frog tadpoles. Adults should not be affected because 

they primarily are air-breathers and because they detect and avoid rotenone by leaving 

the water (Fontenot et al. 1994). The effects of rotenone are reversible if the animal is 

removed from exposure soon enough (Finlayson et al. 2000). The common tree frog 

(Hyla arborea) not only survived treatment of a pond with rotenone, but established a 

reproducing population (Bronmark and Edenhamn 1994). Mortality of canyon tree frog 

during treatment may be limited by the higher likelihood of their presence in the areas to 

be treated with antimycin and lower likelihood in areas to be treated with rotenone, 

because of differences in habitat. Nonnative bullfrog tadpoles may be affected by the 

piscicide, but mortality of all larval bullfrogs is unlikely. Adult bullfrogs would not 

likely be affected. Mechanical methods would be used to capture and kill adult bullfrogs, 

including netting, gigging, firearms, and euthanization. 

No studies of effects of either antimycin A or rotenone on reptiles have been done. 

Black-necked and Mexican gartersnakes are not expected to be affected by either 

antimycin A or rotenone because they are air-breathers (Fontenot et al. 1994). Sonora 

mud turtles could be affected by both piscicides because of their use of aquatic 

respiration (absorption of oxygen through the buccopharyngea, skin, and/or cloaca) 

(Fontenot et al. 1994). Use of rotenone in Lake Conroe in Texas resulted in mortality of 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 52
many mud turtle (Kinosternon subrubrum) at levels within rotenone label levels for 

piscicide use (McCoid and Bettoli 1996). No data is available regarding antimycin A 

toxicity, but in Fossil Creek where an extensive nonnative removal project using high 

concentrations of antimycin A occurred in 2004 (with no turtle salvage), Sonora mud 

turtles were commonly found during post-treatment monitoring in 2005 (Marsh et al. 

2006). To prevent mortalities, Sonora mud turtles would be salvaged prior to piscicide 

application and returned after detoxification. However, not all turtles would be salvaged, 

and some of those remaining in the stream may fail to leave the water before receiving a 

potentially lethal dose of piscicide. 

Macroinvertebrates could suffer some adverse effects from use of piscicides, and those 

effects could differ in areas treated with antimycin A versus rotenone. Effects of 

antimycin A on aquatic invertebrates are variable. Any effects on aquatic insect 

populations are usually short-term, as mortality is incomplete (Minckley and Mihalick 

1981) and recolonization is rapid (Gray 1981; Gray and Fisher 1981). Stefferud (1977) 

found short-term increases in invertebrate drift in high-elevation streams but no change in 

species composition following treatment. Kiner et al. (2000) found no signficant 

differences in species abundance for pre- and post-treatment sites but found significant 

differences in relative abundances of some invertebrate groups. In Arizona, Minckley 

and Mihalik (1981) concluded that long-term changes in the aquatic invertebrate fauna 

resulting from antimycin A treatment of Ord Creek were minimal but that a few taxa may 

have been locally eliminated. Others (Walker et al. 1964; Vezina 1967; Gilderhus et al. 

1969; Lennon and Berger 1970; Snow 1974; Houf and Campbell 1977; Morrison 1979) 

failed to discern adverse effects of antimycin A on invertebrates in general. 

Rotenone is commonly sold in different formulations for use as an insecticide and so has 

a higher potential for adverse effects to the invertebrate community than antimycin. 

Burress (1982) found that piscicide level applications of rotenone caused reductions in 

benthic pond invertebrates and zooplankton but that the populations rebounded rapidly. 

They also found substantial increases in phytoplankton because of released nutrients and 

reduction of plankton-feeding animals. No effects of species diversity, emergence, 

seasonal dynamics, abundance, or relative numbers of taxa were found by Houf and 

Campbell (1977). 

Adverse effects to black-necked and Mexican gartersnake could occur as a result of 

temporary removal of the fish and frog food source. While the major prey of the 

Mexican gartersnake is native fish and frogs, it is known to eat mosquitofish and bullfrog 

tadpoles (Holycross et al. 2006). During the period between the time fish are totally 

removed from the system and the time they are restocked, the prey base of both garter 

snakes would be substantially reduced. However, some frogs would remain, as adult 

frogs would not be killed by the piscicide, and some tadpoles are also expected to 

survive. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 53
Alternative A

The area of effect from implementation of Alternative A is smaller than that of the 

Proposed Action. Because of this, aquatic species and their habitat in approximately 7 

miles of stream would not receive the benefits of nonnative removal and native species 

restoration. Potential adverse effects of a barrier through loss of gene flow, 

fragmentation, and larval drift (discussed under the Proposed Action) would not occur if 

Alternative A is implemented. 

Without a constructed barrier, this alternative may result in the long-term loss of all 

native fish populations from the reach of Redrock Canyon below the natural barrier of the 

Falls. This would include Oak Grove Spring Canyon and its tributaries below the natural 

barriers on those streams (Figure 4). Other native aquatic species would also likely be 

excluded from this reach over time, as existing nonnatives and others moving upstream 

from Sonoita Creek (e.g., yellow bullhead, green sunfish) become dominant. 

Benefits to the native aquatic wildlife would be similar in nature to those discussed for 

the Proposed Action, but to a lesser extent. Removal of nonnatives without blocking 

their route of reinvasion (i.e., a barrier) has little long-term value. Therefore, portions of 

the watershed that lie downstream from the natural barrier at the Falls would not be 

included in the project area. Nonnative removal and native fish restoration would be 

implemented only in those areas upstream of the Falls and upstream of the natural 

barriers on upper Oak Grove Spring Canyon, Redrock Canyon proper below the Falls, 

and in Oak Grove Spring Canyon and its tributaries below their natural barriers. 

Mortality of aquatic species during piscicide application would be slightly less than that 

resulting from implementation of the Proposed Action because of the reduced area to 

which treatment would be applied. 

Cumulative Effects – Fish and Aquatic Wildlife

Effects to aquatic wildlife from either of the two action alternatives are cumulative to the 

ongoing impacts from livestock grazing, roads, and other human uses in the watershed. 

See the cumulative effects discussion in Section 3.1.2 for more detail on cumulative 

effects to water quantity, quality, and channel geomorphology. Either of the two action 

alternatives would reduce stress on native aquatic species populations from nonnative 

species. This would make the native species able to better withstand the stresses 

resulting from livestock grazing. 

3.2.7 Affected Environment -- Federally listed Species 

The FWS identifies nine species with potential to occur in the project vicinity (Table 3). 

Four of them would not be affected by the project because either they are not known to 

occur in the Redrock Canyon watershed, and/or there is no suitable habitat for them in the 

project area: Huachuca water umbel, Canelo Hills ladies tresses, Mexican spotted owl, 

and jaguar. Effects to the remaining five listed species in Table 3 were reported in a 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 54
Biological Assessment prepared for this project (USFS and Reclamation 2007). A 

discussion of these species follows below. 

Table 3. Federally listed or candidate species addressed in this EA. 

COMMON NAME SCIENTIFIC NAME STATUS OCCURRENCE 

Plants 

Huachuca water 

umbel 

Lilaeopsis schaffneriana var. 

recurva 

Endangered Not recorded in project area 

Canelo Hills ladies 

tresses 

Spiranthes delitescens Endangered Closest known population is 

at O’Donnell Creek 

Amphibians 

Sonora tiger 

salamander 

Ambystoma tigrinum stebbinsi Endangered Recorded in project area 

Chiricahua leopard 

frog 

Rana chiricahuensis Threatened Recorded in project area 

Fish 

Gila topminnow Poeciliopsis occidentalis Endangered Recorded in project area 

Gila chub Gila intermedia Endangered Suitable habitat but no 

records 

Birds 

Mexican spotted owl Strix occidentalis lucida Threatened Nearest Protected Activity 

Center is 1 mile south 

Mammals 

Lesser long-nosed 

bat 

Leptonycteris curasoae 

yerbabuenae 

Endangered Foraging habitat in project 

area 

Jaguar Panthera onca Endangered Nearest recent record is in the 

Huachuca Mountains 

Source: FWS web site at “www.fws.gov/southwest/es/arizona/documents/countylists/santacruz.pdf”” 

Sonora tiger salamander. Listed as endangered in 1997, the salamander was only 

recently discovered in the Redrock Canyon watershed. In February 2003, Sonora tiger 

salamanders were found in Oak Tank in the east fork of the north fork of Oak Grove 

Spring Canyon (AGFD records – the record is referred to Kunde Tank, as synonym for 

Oak Tank). Earlier reports of salamanders in Sink Hole Tank in the upper reaches of an 

unnamed tributary to Lampshire Canyon have not been verified. Eggs and larvae of this 

salamander are completely aquatic. Adults may remain gilled (branchiate) or may 

metamorphose to an air-breathing form. As larvae or branchiate adults, they feed on 

zooplankton and macroinvertebrates; and, as terrestrial adults, they eat terrestrial and 

aquatic macroinvertebrates (Collins and Snyder 2002). They prefer soft substrates and 

perennial water. The 2002 Recovery Plan for Sonora tiger salamander does not 

specifically mention Redrock Canyon, because that population was unknown at the time 

the plan was completed. However, it calls for removal of nonnatives from any ponds that 

contain Sonora tiger salamander (Collins and Snyder 2002). 

Chiricahua leopard frog. This species was listed as endangered in 2002. It is known 

from the Oak Grove Spring Canyon tributary of Redrock Canyon since 1995 (Scott 

1995). There are earlier anecdotal records of probable leopard frogs in Redrock Canyon, 

but the identity of those individuals cannot be confirmed. In 2003, Chiricahua leopard 

frogs were found inhabiting Oak Tank, the same stock tank in Oak Grove Spring Canyon 

where Sonora tiger salamanders were found. Chiricahua leopard frog has experienced 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 55
severe declines throughout its range due, in part, to predation and competition by 

nonnative fishes, bullfrogs, tiger salamanders, and crayfish (FWS 2007). It is likely the 

species historically occupied much of the surface water within the Redrock Canyon 

watershed but was reduced by loss of surface water due to human activities, the arrival of 

nonnative fishes by the 1970s, and the 1980s’ invasion of bullfrog. Chiricahua leopard 

frog tadpoles are primarily herbivorous and occupy still to moderately flowing waters in 

springs, streams, and ponds. Adult frogs are opportunistic and eat terrestrial and aquatic 

invertebrates, fish, frogs, toads, and other animals. The Recovery Plan for Chiricahua 

leopard frog calls for elimination of nonnative predators at or near Chiricahua leopard 

frog populations, measures to prevent their reinvasion, and establishment of new or 

reestablishment of former populations (FWS 2007). 

Gila topminnow. This species has been recognized as an endangered species since 1967. 

Although the population in Redrock Canyon was not known until 1978, it was known 

from Sonoita Creek, and there were earlier unverified reports of it from Redrock Canyon 

(Rinne et al. 1980). At the time of its discovery, it was one of only two natural 

populations on Federal lands. Since that time, the other natural population (Cocio Wash 

on Bureau of Land Management (BLM) lands) has been extirpated, but an additional 

natural population (Cienega Creek) has been acquired by BLM. Although Gila 

topminnow was probably historically widespread on Forest Service lands in the Gila 

River basin, Redrock Canyon contains the only natural Gila topminnow population 

surviving on any National Forest (FWS 1998). 

The Cienega Creek population of Gila topminnow on BLM lands is vulnerable to adverse 

effects from upstream water and land uses because a large part of the upper watershed is 

in private ownership and supports significant urban, suburban, and rural growth. An 

important advantage Redrock Canyon possesses as a recovery area for Gila topminnow 

and four other native fishes is Federal ownership of >99% of the watershed above the 

National Forest boundary, thus eliminating many potential threats from upstream land 

and water use. Only two small private inholdings exist in Redrock Canyon (Figure 2). 

One, of approximately 60 acres, is located in upper Cott Tank drainage and is the site of 

Cott Tank. At present, it is used only for livestock grazing. The other is a 160-acre 

parcel located in the heart of Redrock Canyon just upstream from the Falls. It was 

originally a homestead and the headquarters of a livestock ranch but is currently 

unoccupied. 

Despite efforts for recovery of Gila topminnow through introduction of new populations, 

its status continues to be poor (Desert Fishes Team 2003). Natural populations continue 

to decline and disappear, and introductions meet with limited success. Loss of natural 

populations within the past 20 years is almost exclusively associated with establishment 

or expansion of populations of nonnative species, particularly mosquitofish (Minckley 

1999). 

The Revised Recovery Plan for Gila topminnow calls for building and maintaining 

barriers against nonnative fishes, removal of nonnatives present in Gila topminnow 

occupied habitats, and protection and enhancement of existing populations (FWS 1998). 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 56
The 2000 draft revision of the Recovery Plan specifically calls for a barrier and nonnative 

fish removal at Redrock Canyon (Weedman 2000). Repatriation into historic habitats is a 

major element of the recovery program. However, the recent dramatic decline of Gila 

topminnow in Redrock Canyon was not foreseen in the plan, and it does not address 

restocking of the Redrock population. 

Gila chub. This fish was listed in 2005 and does not yet have a recovery plan. It has 

never been recorded from Redrock Canyon but was known from Monkey Spring to the 

northwest (Minckley 1969) of Redrock Canyon and still exists in O’Donnell Canyon and 

Sheehy Spring to the northeast and south (Weedman et al. 1996). Cienega habitat, such 

as is present in Cott Tank drainage and may once have been present in other portions of 

the canyon, provides suitable habitat for Gila chub. Downcutting and other changes to 

channel geomorphology, human use of the water, nonnative predation, and earlier 

droughts may have alone or in combination extirpated Gila chub from Redrock Canyon 

before fish sampling began in the early 1970s. Gila chub and Gila topminnow were both 

historically found in Monkey Spring, O’Donnell Creek, and Sheehy Spring, indicating 

that they are co-evolved species capable of long-term coexistence. Gila chub are 

opportunistic carnivores and feed on macroinvertebrates, small fish, and tadpoles 

(Weedman et al. 1996). 

Lesser long-nosed bat. The lesser long-nosed bat was listed in 1988. This species 

overwinters in Mexico and moves north in the spring to maternity colonies and lower 

elevations near blooming columnar cacti. Three known post-maternity bat roosts of 

greater than 250 bats occur in the vicinity of the proposed project (USFS 2003). The 

closest roost is at Patagonia Bat Cave, which is typically occupied from mid-July through 

mid-September (Fleming 1997). Lesser long-nosed bats from these roosts likely forage 

in the Redrock Canyon watershed. The two cacti used by the bats are not present in 

Redrock Canyon, but both paniculate agaves are present. The extent to which lesser 

long-nosed bats use the most common agave in Redrock Canyon, Scott agave, or amole 

(Agave schottii) is unknown (FWS 2002). 

3.2.8 Environmental Consequences -- Federally listed Species 

No Action

With no action, nonnative species would continue to pose a threat to federally listed 

aquatic species in the Redrock Canyon watershed, and future invasions, via upstream 

migration and through upstream stock tanks, are likely. Because of natural barriers, 

extirpated federally listed fish are not likely to recolonize Redrock Canyon without 

human intervention. 

If no action is taken, populations of Gila topminnow, Chiricahua leopard frog, and 

Sonora tiger salamander would likely continue to decline in the Redrock Canyon 

watershed. Restoration of Gila chub into Redrock Canyon would not occur. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 57
Declining water availability in the presence of mosquitofish and bullfrogs is likely to 

result in extirpation of the native fish and frogs but is unlikely to completely exterminate 

nonnatives. Once areas become rewatered, mosquitofish will move out to recolonize 

available water. Bullfrogs would likely be more vulnerable than mosquitofish to the 

effects of drought; Snyder (2006) found that bullfrogs are eliminated from stock tanks 

that dry completely. 

Proposed Action

The Proposed Action is intended to have an overall benefit on federally listed amphibians 

and fish. The project would assist in the attainment of the objectives of the Gila 

topminnow, Sonora tiger salamander, and Chiricahua leopard frog recovery plans. It 

would also implement recommendations for conservation of Gila chub. The constructed 

barrier would provide a reinvasion-prevention mechanism to allow successful removal of 

nonnatives in the reach of Redrock Canyon below the Falls and in lower Oak Grove 

Spring Canyon. Other benefits to listed species would be similar to those described for 

non-listed amphibians and fish in Section 3.2.6. 

Barrier construction would not likely adversely affect federally listed fish species in the 

short-term, because few are likely to be at or near the barrier site during construction. 

Gila topminnows have been found near the construction site in years of good surface 

water (Stefferud unpub. data). If topminnows are observed during construction, every 

attempt would be made to salvage individuals and move them to existing captive 

populations using the quarantine procedure described in Section 2.3. Nevertheless, there 

is a very low probability that a few individuals may be injured and/or killed by 

construction activities or by vehicle traffic in the stream corridor below the barrier. This 

possible negative effect would be minor in comparison with the substantial benefit to 

Gila topminnow from exclusion of nonnative species moving upstream. No federally 

listed amphibian species, or suitable habitat, exist at or near the site of the proposed 

barrier or at the staging area. 

Beneficial effects to listed fish and amphibian species from removal of nonnatives would 

be long-term. Release of existing populations from the pressure of nonnative predation 

would allow them to reoccupy all available habitats, subject to the constraints of 

precipitation and surface water availability. Removal of nonnatives will allow a good 

likelihood for successful restoration of the three federally listed fish and amphibians 

through restocking, an activity with a very low probability of success in the presence of 

mosquitofish and bullfrogs (Lydeard and Belk 1993). 

Piscicide application to remove nonnative species has the potential to concurrently kill 

individuals of federally listed native species not removed during salvage activities. 

Revival of natives affected by rotentone has been reported (Finlayson et al. 2000). This 

technique was effective for recent rotenone treatments in Sonora tiger salamanderoccupied tanks in the San Rafael Valley (J. Rorabaugh, FWS, pers. com, August 2006). 

It may also be effective for Chiricahua leopard frog adults, if any are affected by the 

rotenone. However, the close physical resemblance of Chiricahua leopard frog tadpoles 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 58
and Gila topminnow to similar nonnatives make this type of rescue operation difficult 

and risky. The loss of a few individuals of these two species would be acceptable when 

compared with the substantial improvement in the long-term status of their populations in 

the Redrock Canyon watershed that would be afforded by the Proposed Action. 

Restoration of native listed species in the Redrock Canyon watershed through restocking 

of salvaged and captive-bred, or translocated individuals would increase the abundance 

and distribution of Gila topminnow, Chiricahua leopard frog, and Sonora tiger 

salamander in this watershed. This, in turn, would contribute substantially toward 

recovery of these species. The ultimate goal of the Proposed Action is the removal of 

nonnatives, prevention of their reinvasion, and restocking of native aquatic species, 

including the entire suite of native fishes, which would result in a self-sustaining aquatic 

species assemblage in Redrock Canyon. 

No adverse effect on lesser long-nosed bat is anticipated because implementation 

activities (construction and piscicide application) would not affect any appreciable 

numbers of agave potentially used for foraging, nor would these activities occur during 

the period when lesser long-nosed bat is expected to use nearby roosts. 

Alternative A

With implementation of Alternative A, renovation would occur, but an important 

mechanism for preventing reinvasion would be omitted. Further, a portion of the 

watershed would be omitted from restoration actions if this alternative is implemented. 

Without a downstream barrier, the restocking of native fish or amphibians into the lower 

reach where nonnatives still exist offers little probability of successful enhancement or 

even survival of the native species. Stocking fish is a well-used method to increase their 

abundance and distribution and is commonly used in recovery activities. However, 

Minckley (1995) pointed out that unless the reason for extirpation is removed, the 

likelihood of success is low. In Redrock Canyon, considerable effort has been made to 

remove some of the reasons for decline of native aquatic species, including exclusion of 

livestock grazing from certain areas, road closures, and localized erosion control. 

Despite this, the effect of nonnative presence has been sufficient to preclude reversal of 

native population declines. When past water flow has been good, some natives, such as 

the Gila topminnow, have been able to maintain the status quo, but the recent addition of 

drought has caused Gila topminnow populations to decline significantly despite these 

inititatives. 

Given the smaller project area, the benefits of Alternative A realized by nonnative 

removal would be commensurately smaller than those to be realized by implementation 

of the Proposed Action. The type and mechanism of benefits from nonnative removal are 

similar to those already discussed for the proposed action. For the same reason, mortality 

to individuals of federally listed species missed during salvage operations would be less. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 59
Cumulative Effects – Federally listed Species

Livestock grazing and management, including development of stock tanks, ground-water 

pumping, and transport of water from streams, springs, and aquifers have cumulatively 

caused adverse impacts on Gila topminnow, Chiricahua leopard frog, and Sonora tiger 

salamander in the Redrock Canyon watershed. Although distribution of waters to the 

uplands through creation of stock tanks serves to reduce impacts of cattle on riparian 

areas by providing better forage-use distribution throughout the watershed, negative 

effects of livestock grazing to fish and their habitats include: (1) increases in summer 

stream temperatures resulting from loss of overhanging vegetation that are less suited to 

fish physiologies; (2) increased sedimentation from bank and upland erosion that traps 

and suffocates eggs and fry; (3) increased channel width because of hoof-induced bank 

sloughing and consequent erosion that reduces stream cover and decreases winter stream 

temperatures; (4) stream channel trenching or braiding that degrades instream habitats 

and increases the streams’ susceptibility to catastrophic floods; and, (5) plant community 

alteration and vegetation loss that reduce bank cohesiveness, cover attributes, and 

terrestrial food inputs (Kauffman and Krueger 1984, Platts and Raleigh 1984, Armour et 

al. 1991, Platts 1991, Belsky et al. 1999). Substantial effort has been made to alleviate 

direct effects of livestock on the perennial waters of Redrock Canyon through exclusion 

of cattle from the riparian areas and an upland buffer. 

Taking no action would not contribute to these cumulative adverse effects to federally 

listed species but would also not have a beneficial effect on the decline of their respective 

populations. Both of the action alternatives may contribute to the loss of a few 

individuals of federally listed species, but the degree of this loss would be discountable 

relative to the much greater impacts on these species from livestock grazing and 

management in the watershed. 

3.2.9 Affected Environment -- Forest Service Special Status Species (FSS) 

FSS and MIS that may occur in the project area are identified in Tables 4 and 5, along 

with species protected by Arizona Native Plant Law (NPL). 

Forest Service Sensitive (FSS) Species. These species are unique to each Region of the 

Forest Service; the Forest Service Region 3 FSS list United States Department of 

Agriculture (USDA) (USDA 1999) applies to the CNF. FSS are listed by the Regional 

Forester as “sensitive” because there is concern for population viability across their 

range, and all occurrences contribute significantly to the conservation of the species. 

Forest Service Manual (FSM) 2670.32 directs that a biological evaluation be prepared to 

determine potential effects on species designated as “sensitive” by the Regional Forester. 

USDA Regulation 9500-4 directs the Forest Service to avoid actions that may cause a 

sensitive species to become threatened or endangered (FSM 2670.12). Populations of all 

FSS wildlife, fish, and plants must be maintained at viable levels in habitats distributed 

throughout their geographic range on NFS lands (FSM 2670.22). The population 

viability of FSS species becomes a concern when downward trends in or habitat 

capability are predicted. Whenever the Forest Service undertakes or approves an activity 

on NFS lands, the agency seeks to avoid or minimize impacts to FSS. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 60
Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 61
Table 4. FSS on the Coronado National Forest. 

COMMON NAME SCIENTIFIC NAME

Mammals 

Arizona shrew Sorex arizonae 

Huachuca Mountains pocket gopher Thomomys umbrinus intermedius 

Birds 

Gould’s turkey Meleagris gallopavo mexicana 

Apache goshawk Accipiter gentilis apache 

Northern gray hawk Asturina nitida maxima 

Baird’s sparrow Ammodramus bairdii 

Chihuahua savannah sparrow Passerculus sandwichensis 

Amphibians 

Western barking frog Eleutherodactylus augusti cactorum 

Reptiles

Mexican gartersnake Thamnophis eques megalops 

Fish 

Desert sucker Pantosteus clarki 

Sonora sucker Catostomus insignis 

Invertebrates 

Giant aryxna skipper Agathymus aryxna 

Brigadier skipper Agathymus evansii 

Poling’s giant skipper Agathymus polingi 

Pima orange tip Anthocharis pima 

Crescent metalmark Apodemia phyciodoides 

Arizona metalmark Calephelis arizonenesis 

Obsolete viceroy butterfly Limenitis archippus obsoleta 

Ursine giant skipper Megathymus ursus 

Spotted skipperling Piruna polingii 

Mexican meadowfly Sympetrum signiferum 

Plants 

Santa Cruz agave* Agave parviflora var. parviflora 

Saiya* Amoreuxia gonazlezii 

Large-flowered blue star Amsonia grandiflora 

Lemmon milkweed Asclepias lemmonii 

Greene milkweed Asclepias uncialis 

Huachuca milk vetch* Astragalus hypoxylus 

No common name Browallia eludens 

Chiltepin Capsicum annuum 

Sedge Carex chihuahensis 

Sedge Carex ultra 

Santa Cruz beehive cactus* Coryphantha recurvata 

No common name Coursetia glabella 

No common name Erigeron arsolius 

Bartram’s stonecrop* Graptopetalum bartramii 

Mock pennyroyal Hedoma dentatum 

Huachuca golden aster Heterotheca rutteri 

Arizona alum root Heuchera glomerulata 

No common name Hexalectris revoluta 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 62
Table 4. Continued. 

COMMON NAME SCIENTIFIC NAME

Texas purple spike* Hexalectris warnockii 

Huachuca morning glory Ipomoea plummerae var. cuneifolia 

Lemmon’s morning glory Ipomoea tenuiloba var. lemmonii 

Thurbers’s morning glory Ipomoea thurberi 

Wooly fleabane Laennecia eriophylla 

Supine bean* Macroptilum supinum 

Escoba Marina diffusa 

Wiggins milkweed vine Metastelma mexicanum 

Box Canyon muhly Muhlenbergia dubioides 

Beardless chinch weed Pectis imberbis

Superb beardtongue Penstemon superbus 

Chiricahua brookweed Samolus vagans 

Nodding blue-eyed grass Sisyrinchium cernuum 

Lumholtz nightshade Solanum lumholtzianum 

Lemmon’s stevia Stevia lemmonii 

Pinos Altos flame flower* Talinum humile 

Tepic flame flower* Talinum marginatum 

Thurber hoary pea Tephrosia thurberi 

Sonora noseburn Tragia laciniata 

* Protected under Arizona Native Plant Law. 

Source: Forest Service, Southwestern Region Sensitive Species List, Regional Forester memorandum to 

Forest Supervisors, July 21, 1999. 

Management Indicator Species (MIS). MIS are selected as representative of many other 

species. As such, they provide a basis for overall Forest management based, in part, on 

the effects on these species and their habitats. National Forest Management Act (NFMA) 

implementing regulations (36 CFR 219.19) and FSM 2600 guidelines require that Forest 

Plans identify certain vertebrate and/or invertebrate species as MIS, and that these species 

be monitored “in order to assess the effects of management activities on their populations 

and the populations of other species with similar habitat needs which they represent 

(FSM 2620.5). 

MIS species and habitat are monitored to observe trends in resources, evaluate 

management actions, and provide a timely warning of problems or undesirable conditions 

affecting the resource. MIS were designated during the development of each Forest Plan 

based on the following criteria: threatened or endangered, requiring of special habitat 

needs, or in high public demand. The analysis of impacts to MIS as part of the NEPA 

process contributes to the identification of trends, which may necessitate development of 

mitigation or new alternatives when a proposed action is under consideration. 

Table 5. MIS on the Coronado National Forest. 

COMMON NAME SCIENTIFIC NAME

Cavity-nesting birds* 

Northern gray hawk Asturina nitida maxima

Arizona tree frog Hyla eximia

Peregrine falcon Falco peregrinus

Mearn’s quail Crytonyx montezumae mearnsi

White-tailed deer Odocoileus virginianus

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 63
Table 5. Continued. 

COMMON NAME SCIENTIFIC NAME

Black bear Ursus americanus

Rose-throated becard Pachyramphus aglaiae

Thick-billed kingbird Tyrannus crassirostris

Sulphur-bellied flycatcher Myiodynastes luteiventris

Northern beardless tyrannulet Camptostoma imberbe

Bell’s vireo Vireo bellii

Five-striped sparrow Amphispiza quinquestriata

*Primary cavity nesters: ladder-backed, Arizona, Gila, acorn, and hairy woodpeckers, northern flicker 

*Secondary cavity-nesters: American kestrel; elf, flammulated, whiskered screech, western screech, and 

northern pygmy owls; brown-crested, ash-throated, dusky, and Cordilleran flycatchers; violet green 

swallow, juniper and bridled titmice, white-breasted nuthatch, house and Bewick’s wren, eastern bluebird, 

European starling, and Lucy’s warbler. 

3.2.10 Environmental Consequences -- Forest Service Special Status Species 

There would be no net loss of habitat for the species listed in Tables 4 and 5 as a result of 

this action. The two action alternatives would have no effect on populations or trends 

toward Federal listing of most FSS and MIS (USFS and Reclamation 2007). The 

exceptions are the desert sucker, Sonora sucker, western barking frog, Mexican 

gartersnake, and the two sedges because of their proximity to stream bottoms where the 

activities of the two action alternatives would occur. But, Sonora sucker has never been 

recorded from Redrock Canyon and is not presently found in Sonoita Creek upstream of 

Patagonia Lake (Rodgeveller 2000; Foster and Mitchell 2005; Killeen 2005). Western 

barking frog has been found in mountains both to the east (Huachuca Mountains) and 

west (Santa Rita Mountains) but has never been recorded from the Redrock Canyon 

watershed. Potential effects to Mexican gartersnake and desert sucker are discussed in 

Section 3.2.6 because of the similarity of issues and effects to other non-listed fish and 

aquatic wildlife. Several species birds on the FSS and MIS lists use riparian vegetation 

and are discussed below. 

No Action

The No Action alternative would affect only those species that would benefit from a 

barrier, aquatic nonnative removal, native fish restoration, and management changes to 

minimize risks of aquatic nonnative reinvasions. The effect would be negative because 

of a loss of the conservation that would accrue as a result of those actions. In the list of 

FSS and MIS, only desert sucker meets those criteria. Effects to this species were 

discussed in Section 3.2.6. 

Proposed Action

The population of northern gray hawk is apparently stable (Csargo 2002). It uses riparian 

woodland with large trees, usually near mesquite forests, and forages on lizards and small 

mammals. It is only present in the area from mid-March to mid-autumn. Although gray 

hawk may be present in areas where Proposed Action activities occur, the only activity 

that has a potential to disturb the hawk is barrier construction. Because no large riparian 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 64
trees would be removed, no adverse effects on the gray hawk are expected from the 

Proposed Action. 

The blue-throated hummingbird, rose-throated becard, sulphur-bellied flycatcher, thickbilled kingbird, northern beardless tyrannulet, and Bell’s vireo are birds recorded in or 

near the Redrock Canyon watershed and that use riparian or mesquite bosque habitats. 

Primary threats to these species are from destruction of riparian areas. No riparian loss 

would occur as a result of the Proposed Action, and no other effects are expected to the 

vegetation used as habitat for these birds or to the insects that comprise their food. 

The closest known population of the sedge Carex ultra is in the Huachuca Mountains, 

and the closest known population of Carex chihuahensis is in the Santa Rita Mountains. 

There is a potential for either of the two species to exist in Redrock Canyon. Because 

they are associated with wetted areas, if present in Redrock Canyon, they could 

potentially occur in areas affected by the action alternatives. The barrier site is not 

typical habitat for most Carex, and it is unlikely either species is present. Nonnative 

removal and native species restoration activities are unlikely to affect either species, if 

present. Although there would be foot traffic along areas of surface water, it would not 

be of sufficient volume or intensity to destroy sedges. Temporary dewatering of stock 

tanks has the greatest potential for effects to the two sedges. However, the immediate 

vicinity of stock tanks tends to be largely unvegetated because of heavy livestock use and 

periodic use of heavy equipment to dredge and repair the tanks. Vegetation that occurs 

tends toward disturbance and weedy species, not species more associated with stable 

riparian areas, such as sedges. Prior to any dewatering of stock tanks, surveys for these 

sedges would be conducted. 

Alternative A

The alternative of renovating and restoring native species without barrier construction 

would have a lesser effect on FSS and MIS than the proposed action. Without barrier 

construction, the slight possibility of injury or mortality during construction would be 

eliminated. Otherwise the effects of this alternative would be the same as those described 

for the Proposed Action. 

Cumulative Effects - Forest Service Special Status Species

The primary activity affecting habitat for FSS and MIS in the Redrock Canyon watershed 

is livestock grazing. Roads, water developments associated with livestock grazing, and 

immigration and border control activities also have adverse effects. Careless use of 

backcountry fires by immigrants are an important cause of wildfire. Neither of the two 

action alternatives is expected to add to the cumulative impacts of these activities. 

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Native Fish Restoration in Redrock Canyon 65
3.3 CULTURAL RESOURCES 

3.3.1 Affected Environment 

 

Southern Arizona was occupied by small mobile bands of hunter-gathers from the 

beginning of the Paleoindian period about 11,000 B.C. to the end of the Archaic period 

around 1200 B.C. By the end of the Archaic, pithouse villages were established near 

agricultural fields along the larger streams, while procurement and camp sites continued 

to be located away from major river valleys. Probable Archaic sites are represented by 

lithic scatters and possible camp sites on ridge tops and near water sources in and around 

the Patagonia Mountains. 

An agricultural economy, combined with hunting and wild plant collecting, continued to 

be followed throughout the rest of the Early Agricultural and Ceramic period (ending ca. 

AD 1450) in southern Arizona. Ceramic period occupation in the Redrock Canyon area 

is indicated by scattered habitation sites along major drainages as well as smaller, 

probable special use sites. Ceramics and other artifacts from identified sites suggest 

interaction with the Trincheras Culture to the south as well as the Hohokam to the north. 

The O’odham occupied the area around Redrock Canyon and nearby Sonoita Creek when 

the Spanish first visited the area in the 1690s. After settling in the Santa Cruz Valley, 

Spanish settlers also used the area for limited mining, charcoal production, and grazing 

until increased Apache hostilities forced its abandonment in the mid to late 1700s. The 

Patagonia area was used intermittently by the O’odham, Mexicans, and Americans after 

the Gadsden Purchase (1854) when southern Arizona became a territory of the United 

States. Mining and grazing became better established after Apache hostilities declined in 

the 1880s, and grazing continues to be the major land use in the area today. 

Most archaeological surveys in the project area have been conducted by the Forest 

Service in association with a number of range management projects, including fencelines, 

riparian exclosures, and stock tanks. Four previously identified archaeological sites are 

located within a mile of the project area, but none are close enough to be affected by the 

fish barrier construction or related activities. All four represent prehistoric ceramic period 

occupations. The closest site is situated on the north bank of Redrock Creek less than 1⁄4 

of a mile above the fish barrier. This habitation site’s location on a high terrace above the 

stream precludes any impact from possible sedimentation behind the barrier. 

The project scoping letter was sent to 12 Native American tribes with traditional ties to 

southeastern Arizona; no comments were received. Archaeologists from Reclamation 

and CNF conducted a Class III Survey of the areas that would undergo ground-disturbing 

activities, including the access route, fish barrier locale, temporary laydown area, and 

staging area. No cultural resources were identified within the footprint of the proposed 

construction area. A finding of “no historic properties affected” was made by 

Reclamation following the survey. The CNF concurred with this finding in an Inventory 

Standards and Accounting form, signed by Forest Archaeologist Mary Farrell and Forest 

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Native Fish Restoration in Redrock Canyon 66
Supervisor Jeanine Derby on December 8, 2006. The State Historic Preservation Office 

concurred with this determination on January 11, 2007. 

3.3.2 Environmental Consequences 

No Action

There would be no change in existing conditions. Environmental factors, including 

surface and channel erosion as well as cattle grazing, would continue to affect any 

resources in the area. It is assumed that current land use and management practices 

would continue, as would Federal protections to cultural properties now in place. 

Minimal impact to cultural resources would be anticipated as the result of not 

implementing the Redrock Canyon fish restoration project. 

Proposed Action

For the most part, ground-disturbing activities would be limited to fish barrier 

construction and related tasks. The proposed fish restoration activities (native salvage, 

nonnative removal, native restoration, monitoring) would have minimal to no impact to 

any potential cultural resources in the area. 

Construction of the fish barrier, including temporary access up the streambed, a laydown 

area, and staging area along the road would not impact any known cultural resources or 

archaeological sites within the project area. While the addition of a barrier may result in 

upstream sediment buildup within the channel, the closest archaeological site is located 

on a high terrace over 1,000 feet upstream and would not be affected by increased 

sedimentation. 

Nonnative species removal and native fish restoration would not involve any grounddisturbing activities and would largely take place in the immediate vicinity of water 

resources with margins previously disturbed by flooding or tank construction. These 

activities would have no effect on cultural resources within the fish restoration area. 

 

Alternative A

This alternative would have no potential to affect cultural resources. With Alternative A, 

there would be no ground-disturbing activities from the fish barrier construction. The 

impact of the activities related to the fish restoration would be minimal.

Cumulative Effects – Cultural Resources

Livestock grazing is the major ongoing use of the project area, with human impacts 

introduced by ranchers, recreational enthusiasts, and other foot and vehicle traffic 

through the area. Because cultural resources would not be affected by either no action or 

the action alternatives, cumulative impacts would not occur. 

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Native Fish Restoration in Redrock Canyon 67
3.4 SOCIOECONOMIC EFFECTS - LIVESTOCK GRAZING 

3.4.1 Affected Environment 

The Redrock Canyon watershed encompasses all or portions of four livestock grazing 

allotments administered by the Forest Service. These allotments are Seibold-Crittenden, 

Kunde, Papago, and San Rafael. Livestock management on each of these allotments is 

guided by an allotment management plan (AMP). Implementation of the AMP is 

documented in the Annual Operating Instructions (AOI). The AOI sets forth the 

maximum permissible grazing use authorized for the upcoming grazing season, the 

planned sequence of grazing, improvements to be constructed, reconstructed or 

maintained; allowable use or other standards to be followed by the permittee; and 

required monitoring for the grazing season. Management of the four allotments is 

described below.

Seibold-Crittenden Allotment. The allotment was created by combination of the 

Crittenden and Seibold Allotments in 2005. The allotment contains ten pastures, of 

which the following six occur within the Redrock Canyon watershed: Corral Canyon 

(small part), Red Bear, Oak Grove, Moonshine, and East Redrock and West Redrock 

Pastures. The first four are grazed by the main herd as part of a six-pasture rotation. The 

East and West Red Rock Pastures are grazed with 30 head of heifers and/or cows for up 

to 90 days (90 Animal Unit Months (AUMs)13) during the winter (November-April), 

except that once every 3 to 5 years the entire herd may graze these two pastures for 

1 month (130 AUMs) in the winter. 

Livestock exclosures were constructed around Pig Camp Spring (0.1 mile) and Gate 

Spring (0.3 mile) in the 1990s on behalf of Gila Topminnow. Oak Grove Spring was 

fenced in 2001 with the expectation that excluding livestock grazing would develop 

habitat for Gila topminnow; however, the habitat did not develop in the last 6 years. The 

stream in the West Redrock pasture was fenced to exclude livestock in 2002. All of these 

exclosures are maintained and monitored by the grazing permittee and/or Forest personel 

at least once a year to ensure the fences are functional. 

Kunde Allotment. The Kunde Allotment occupies the middle portion of the drainage and 

consists of four pastures: Holding, Lower Lampshire, Upper Lampshire, and Redrock. 

Redrock Canyon passes through the Redrock Pasture. Historically, one of the greatest 

challenges to successful management of the Kunde Allotment has been poor water 

availability in the rougher pastures and adherence to the grazing rotation schedule. This 

would often result in overuse of the lower pasture where reliable water was available. 

Livestock management was changed in 1991 to require winter use only in pastures along 

Redrock Creek. Permitted numbers were reduced from 100 Cattle Yearlong (CYL)14 to 

53 CYL. The Falls exclosure (0.5 mile) and Gate Springs exclosure (0.3 mile) were 

constructed to protect two of the wettest sections of the creek. Further reductions 

occurred in 2004 when the Forest issued a decision to exclude grazing from the Redrock 

 

13 One AUM is equivalent to enough forage to support one adult cow without a calf for 1 month’s time. 

14 CYL represents the number of adult cattle that are being raised year-round. 

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Native Fish Restoration in Redrock Canyon 68
Pasture to reduce grazing impacts to the Gila topminnow and to improve riparian and 

watershed condition. Permitted numbers of cattle were reduced to 31 CYL to reflect the 

reduction in available capable acres. The AMP established a three-pasture rotational 

grazing schedule using Upper Lampshire, Lower Lampshire, and Holding pastures to 

allow growing season rest in all pastures, at least every other year. The permit was 

waived to a new permittee and has been in non-use for resource protection purposes since 

then. 

Papago Allotment. The allotment consists of a 14-pasture deferred rotation grazing 

system, of which Lampshire pasture is the only one within the Redrock Canyon 

watershed. Lampshire Pasture is grazed annually during December-January or FebruaryMarch. The main feature in this pasture is Box Canyon, a tributary to Lampshire Canyon 

which flows into Redrock Canyon. Riparian vegetation is limited in Box Canyon, and 

there is no potential for fisheries or amphibians. 

San Rafael Allotment. The upper part of the drainage is included in the San Rafael 

allotment, which is part of the Vaca Ranch headquartered in the San Rafael Valley. 

There are 23 pastures on the Vaca Ranch but only two are within the Redrock Canyon 

watershed: North Redrock and South Redrock. These two pastures are grazed in rotation 

during winter from October through March. Cott Tank (1.9 miles) exclosure was 

constructed in the mid-1990s and extended downstream into Redrock Canyon about 1⁄4 

mile in the early 2000s. 

3.4.2 Environmental Consequences 

No Action

There would be no effect to livestock grazing under this alternative. 

Proposed Action

Barrier Construction and Maintenance. The fish barrier would be constructed in the 

West Redrock pasture on the Seibold-Crittenden Allotment. This pasture is grazed 

during winter once every 3 to 5 years. The proposed barrier site is located within the 

West Redrock Exclosure. This site consists mostly of exposed bedrock and provides 

little if any forage used by livestock. All reasonable efforts would be made to minimize 

removal of trees, and site rehabilitation would occur following project completion. The 

volume of construction traffic is expected to be low and would not disrupt access for the 

livestock grazing permittee. Similarly, periodic operation and maintenance of the fish 

barrier are not anticipated to impact the grazing operation. 

Nonnative Species Removal. Nonnative removal from stock tanks and surface waters 

would occur on all four of the allotments within the project area. Reclamation and the 

Forest Service would cooperate with permittees to avoid disruption of grazing operations. 

Pumping of stock tanks and possibly cienega pools to facilitate nonnative removal may 

affect surface water availability in the short term for livestock if livestock are present 

during or shortly after pumping. If cattle are in the pastures where the tanks are located 

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Native Fish Restoration in Redrock Canyon 69
during treatment, sufficient water would be made available for cattle, including refilling 

tanks or providing an alternative water source if necessary until the stock tanks refill with 

the summer rains. 

Piscicides would be applied in accordance with a Forest Supervisor-approved Pesticide 

Use Proposal during periods of low stream flow. There are approximately 13 stock tanks 

in the watershed, although most are not perennial. Three reaches of Redrock Canyon 

have perennial surface water: Falls, Gate Spring, and Cott Tank drainage. Surface water 

has usually also been present in the West Redrock pasture, at Pig Spring, and Oak Grove 

Spring, and approximately 0.25 miles upstream of Redrock Ranch on the border of 

Sections 7 and 12. Livestock are excluded from these areas and would not have access to 

the water during treatment with piscicides. 

Piscicides would also be applied to surface water outside of livestock exclosures, such as 

stock ponds. Cattle are not expected to be affected by either rotenone or antimycin A. 

Rotenone has been used as a control for grub on dairy and beef cattle for many years with 

no adverse effects, and the EPA has reported that there is no need to restrict livestock 

consumption of treated waters (Finlayson et al. 2000). However, alternative water 

sources for livestock would be provided as appropriate during the project, to prevent 

disruption of cattle access to water or to draw cattle away from areas of project activity 

where their presence may disrupt project implementation. 

 

Native Species Transplants 

Gila topminnow. Gila topminnow has been documented in Redrock Canyon since at 

least 1979 (Rinne et al. 1980). The importance of Redrock Canyon to recovery of Gila 

topminnow is well-established (Recovery Plan). Consultation with FWS since 1990 has 

resulted in four biological opinions that specifically address management in Redrock 

Canyon: the Redrock Canyon Action Plan (2-21-90-F-169b), the Canelo Pass to 

Patagonia Segment of the Arizona Trail (2-21-92-F-350), and the 1998 and 2002 

supplemental Biological Assessment of Ongoing and Long-term Grazing on the 

Coronado National Forest (AESO/SE 2-21-98-F-399 and 2-21-98-F-399-R1). The terms 

and conditions of the biological opinion include several actions necessary to minimize the 

take of Gila topminnow in Redrock Canyon under current management. These actions 

include the construction and maintenance of livestock exclosures, continued monitoring 

of fish and aquatic habitats, and reporting data to the FWS. As a result, about 2.8 miles 

of the Redrock Creek and Cott Tank drainage valley bottom are fenced to exclude 

domestic livestock; livestock are permitted on the unprotected reaches of Redrock Creek 

during winter only; and water tanks, drinkers, and salting areas are on the uplands to 

draw livestock away from the stream and gain better distribution patterns. 

As documented by photo points and data, projects completed during the past decade are 

improving riparian conditions in Redrock Canyon. A series of photos taken at 1,000-foot 

intervals through Redrock Canyon in 1989 and repeated in 1996 and 2001 generally show 

the channel becoming narrower with increased definition of channel banks, substrate 

particle size increasing (as fine sediments are either captured by streambanks vegetation 

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Native Fish Restoration in Redrock Canyon 70
or passed through the system), and recruitment and growth of woody and herbaceous 

riparian plants (Stefferud 2001). In the exclosures, aquatic habitats dramatically 

improved with increases in overhanging vegetation, establishment of defined 

streambanks, and a trend towards enhanced channel stability and higher diversity of 

aquatic habitats. The extent of surface water in time and space and the length of the 

“green line” vegetation have expanded a considerable distance beyond the exclosures. In 

some reaches, herbaceous vegetation is beginning to catch and retain fine sediments 

during over bank flows. 

The proposed augmentation of Gila topminnow, ultimately to establish a self-sustaining 

population, is not anticipated to cause any additional limitations or restrictions for 

livestock grazing. Permittees would continue to be required to adhere to Forest standards 

and guidelines for grazing and the approved AMP, and the Forest Service must ensure all 

terms and conditions for incidental take statements are followed. 

Gila chub. Gila chub has not been recorded in Redrock Canyon. Apparently suitable 

habitat exists in few locations, most notably in Cott Tank drainage. Given completion of 

other required regulatory processes, Gila chub would be reintroduced into this area 

following removal of nonnatives, providing that sufficient surface waters are present. 

Because Gila chub would occupy the same areas as Gila topminnow, management for 

Gila chub is not anticipated to be substantially different than that for Gila topminnow. 

It is anticipated that transplant of Gila chub would not necessitate any additional 

requirements or restrictions for livestock grazing than are already in place for Gila 

topminnow. Specifically, the permittee would be required to inspect and maintain 

livestock exclosure fences and ensure livestock use remains within allowable levels, as 

specified in the AMP. The Forest would be required to monitor the fisheries and stream 

habitat in cooperation with AGFD. 

Chiricahua leopard frog. All four allotments contain potential habitat for Chiricahua 

leopard frogs, but the most likely site for a transplant is historically occupied habitat on 

the Seibold-Crittenden allotment. Grazing occurs in or near most habitats occupied by 

the frogs, and maintenance of viable populations appears to be compatible with wellmanaged livestock grazing. The 2002 biological opinion specifies terms and conditions 

for livestock management activities on the Seibold allotment that are necessary to 

minimize the take of Chiricahua leopard frog. These measures include requirements to 

survey for and salvage frogs during stock pond cleaning activities; measures designed to 

minimize the introduction of nonnative species or chytrid contamination into occupied 

sites; measures to reduce direct mortality and damage to aquatic cover as a result of 

livestock impacts; and the requirement to monitor and report incidental take. In 2005, the 

Forest developed aquatic habitat guidelines for Chiricahua leopard frogs that are intended 

to implement the terms and conditions of the biological opinion. Permittees are notified 

of these terms and conditions in their AOIs. 

It is anticipated that transplant of Chiricahua leopard frog would not trigger any 

additional limitations or restrictions for livestock grazing than are currently in place. 

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Native Fish Restoration in Redrock Canyon 71
Sonora tiger salamander. In an effort to minimize the take of Sonora tiger salamanders 

as a result of routine stockpond maintenance, the Forest has adopted stockpond 

management and maintenance guidelines that are in effect on allotments in the San 

Rafael Valley and surrounding areas. The Forest Service anticipates no additional 

restrictions or changes in livestock management as a result of transplanting Sonora tiger 

salamanders. If management is adequate to maintain stock tanks as they are, the 

populations of Sonora tiger salamander would persist and expand as a result of the 

removal of nonnative species. Cattle ranching and Sonora tiger salamanders have 

coexisted for many decades in Arizona. There is no reason to believe they could not 

continue to coexist. 

Cumulative Effects – Livestock Grazing

Neither action alternative is expected to alter existing livestock grazing practices within 

the watershed. Therefore, the proposed project would not have incremental or additive 

socioeconomic effects on grazing operations. 

3.5 RECREATION AND VISUAL QUALITY 

3.5.1 Affected Environment 

Visual Quality. Landscape character in the project area is comprised of rolling 

topography covered with a mosaic of vegetation that includes semi-desert grassland, 

evergreen oak woodland, and mesquite-prickly pear. Along the creek through Redrock 

Canyon is riparian vegetation comprising of cottonwood, willow, and lush grasses. 

Existing condition of visual quality in the area is generally good. 

Visual Quality Objectives (VQOs) established for National Forest lands provide 

standards that govern proposed alteration of the landscape. The CNF Plan designates the 

project area with a VQO of “Modification,” which means that while management 

activities may visually dominate the characteristic landscape, they must utilize naturally 

established form, line, color, and texture. According to the VQO inventory, the nearest 

visually sensitive travel ways in the project area include Highway 82 (Sensitivity Level 1: 

High) and FSR 58 (Sensitivity Level 2: Average). In addition, a project-level review 

reveals that the Arizona Trail passes through the project area, and this route would 

qualify as a Sensitivity Level 1 travel way. 

Recreation. There are no developed recreation sites in the project area. Dispersed uses 

throughout this part of the forest include scenic driving, hiking, birdwatching, camping, 

and hunting. In the project area, Arizona Trail use (including hiking, horseback riding, 

and mountain biking) and exploration of backroads on off-highway vehicles are popular 

recreation activities. However, there is poor access and rugged terrain in the Redrock 

Canyon watershed, so most recreational use occurs on existing roads and trails. The 

Arizona Trail bisects the upper watershed, but avoids the proposed barrier site. Access 

for high clearance four-wheel drive vehicles is provided by Forest roads. 

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Native Fish Restoration in Redrock Canyon 72
3.5.2 Environmental Consequences 

No Action

There would be no effect to visual quality or recreational use under this alternative. 

Proposed Action

Visual Quality. Many of the proposed activities have little or no impact to visual quality, 

including removal of fish/amphibians/turtles, application of piscicide, reintroduction of 

native fish and amphibians, and monitoring. Construction of a permanent, concrete fish 

barrier impacts visual quality, but when mitigated, the barrier will meet the area’s VQO. 

Mitigation would include: (1) using colored concrete to match adjacent natural rock 

colors for the entire fish barrier (all exposed surfaces including walls and apron); (2) 

minimizing removal of trees and damage to other vegetation; (3) restoring the stream 

channel, staging areas, and vehicle tracks as needed following construction; and (4) 

selecting riprap rock type and color to match native rock. 

Recreation. Most of the proposed activities would have little impact on recreation, and 

construction of the fish barrier is not expected to affect recreational use. Because the 

barrier includes a 5-foot-high, concrete drop structure, there is a potential risk of injury to 

visitors. However, because there are no recreation trails or roads that access the barrier 

site, this risk is minimal. There may be a slight disturbance to recreational users in areas 

where piscicide applications and bullfrog eradication activities are being conducted. 

Mitigation would include: (1) posting cautionary signage (construction and piscicide 

treatment areas) in both English and Spanish, and (2) restoring all disturbed ground 

created by this project, especially tracks or trails that might encourage visitors to access 

the fish barrier, and other areas that might encourage heavier dispersed uses (parking, 

camping, etc.). 

Alternative A

There would be no effect to visual quality under this alternative. Effects to recreation 

would be similar to those described under the Proposed Action for piscicide applications. 

Cumulative Effects -- Recreation and Visual Quality

Proposed project activities, including construction of a fish barrier, would have minor and 

highly localized impacts on the visual quality and recreation. The CNF’s Schedule of 

Proposed Actions currently lists several other activities in or near the proposed project 

area, including grazing allotment management plans, mineral exploration, road 

maintenance, and fuels management. None of these projects will have major impacts to 

visual quality or recreation. Therefore, the cumulative effects from the proposed project 

would be minimal. 

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Native Fish Restoration in Redrock Canyon 73
3.6 SOILS AND GEOLOGY 

3.6.1 Affected Environment 

Geologic units within the Redrock Canyon watershed include surficial alluvium, 

volcanics, metamorphic, and sedimentary rock. Nearly 85 percent of upland soils are 

grouped within the Lampshire-Graham-Rock Outcrop and Chiricahua-Lampshire 

associations (NRCS 2007). These soils consist of cobbly or heavy clay loam and very 

cobbly loam formed on hillsides. Alluvial deposits eroded from upland areas fill the 

canyon bottom and underlie stream terraces. 

Moderately to steeply sloping canyon walls entrench the stream throughout the project 

area. The fish barrier would be located in a narrow cut in a low ridge of basalt that trends 

nearly perpendicular to the canyon walls. At the fish barrier site, the top of the rock 

abutments are approximately 6 feet above the surface of the alluvium. Channel width 

through this rock cut is approximately 10 feet at the surface of the alluvium. 

The channel alluvium consists of fine sand, gravel, and cobbles. Boulders and bedrock 

are present along the channel and occur at various depths within the alluvium. An 

outcrop of basalt forms the channel bed approximately 40-feet upstream of the barrier 

site. At the rock cut, the alluvial deposits extend beyond 7 feet to an unknown depth. 

3.6.2 Environmental Consequences 

No Action

Existing conditions would prevail into the foreseeable future. Unnatural rates of erosion 

and sedimentation would continue as a result of human-induced disturbances within the 

watershed. 

Proposed Action

Construction would directly affect less than 0.1 acre of channel and floodplain substrates 

at the barrier site. Excavation for the barrier foundation would displace an estimated 55 

cubic yards of alluvium, which would be replaced by approximately 5 cubic yards of 

concrete, 8 cubic yards of gabions, and 42 cubic yards of backfill. Surplus material 

excavated from the foundation trench would used as backfill along the upstream side of 

the barrier to minimize temporary pool development following construction. 

A backhoe, drill rig, and pickup truck needed for construction would be “walked” up the 

channel from FSR 138. This would result in a minor disturbance to alluvial soils on a 

3,500-foot segment of normally dry streambed. All other equipment and imported 

material would be transported to the barrier site by helicopter. 

Construction staging would affect approximately 0.1 acre of alluvial soils on a floodplain 

bence at the FSR 138 low-water crossing downstream of the barrier. Approximately 0.02 

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Native Fish Restoration in Redrock Canyon 74
acre of alluvial soils would be affected by construction material lay down on a floodplain 

terrace adjacent to the barrier site. Appropriate post-construction stabilization of these 

areas would be required to minimize potential erosion. 

In the short-term following construction, stream-transported coarse material would be 

immobilized by the barrier, forming a new layer of bedload deposits over existing 

channel substrates. Deposition of this material would be accelerated by seasonal high 

flows and floods. Localized effects include a reduction in gradient and aggradation of the 

active stream channel for approximately 1,475 feet (1.4 acres) upstream of the barrier 

(Figure 6). 

Short-term capture of bedload sediment at the barrier is expected to have minimal impact 

on stream balance downstream. Redrock Canyon carries high coarse sediment loads 

during floods, and the amount of bedload that would be immobilized at the barrier 

relative to the total volume transported within the stream is small. Total sediment yield 

downstream would be consistent with pre-project conditions once streambed aggradation 

at the barrier has stabilized. No long-term impact on sediment transport within the 

stream would occur. 

The proposed action would have a low impact on soils from pedestrian traffic associated 

with stream renovation and native fish and amphibian restoration. 

Alternative A

This alternative would have minimal impact on soils from pedestrian traffic associated 

with stream renovation and native fish and amphibian restoration. 

Cumulative Effects -- Soils and Geology

The effects of project activities on channel features and sedimentation would be 

incremental to historic and ongoing uses of the watershed. During the 20th century, 

livestock grazing, trails (both authorized and unauthorized), and roads were the primary 

human-induced sources of sedimentation. Recreational use was and is a minor 

contributor to sedimentation. Changes in grazing practices have reduced erosion in 

riparian areas and other portions of the watershed, although grazing continues to be a 

source of sedimentation. The proposed native fish restoration project would not add 

substantially to the cumulative impacts of other past, present, or reasonably foreseeable 

actions on soils because of the limited scope of the proposal (short duration and relatively 

small area impacted) and use of appropriate erosion control practices to mitigate soil 

impacts. 

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Native Fish Restoration in Redrock Canyon 75
3.7 AIR QUALITY 

3.7.1 Affected Environment 

Air quality is determined by the ambient concentrations of pollutants that are known to 

have detrimental effects on human health. The U.S. Environmental Protection Agency 

(EPA) has promulgated National Ambient Air Quality Standards (NAAQS) for six 

criteria pollutants: carbon monoxide, nitrogen dioxide, particulate matter (PM10 and 

PM2.5), ozone, sulfur dioxide, and lead. Areas with air quality that do not meet the 

standards are designated as “nonattainment areas.” Designation of nonattainment 

submits an area to regulatory control of pollutant emissions so that attainment of the 

NAAQS can be achieved within a designated time period. The Redrock Canyon 

watershed is located in an attainment area for all regulated NAAQS (EPA 2007). 

Ambient air quality in the area is excellent. 

The Clean Air Act (CAA) provides special protection for visibility and other air quality 

values in specially designated Class I areas where the cleanest and most stringent 

protection from air quality degradation is considered important. These areas include 

National Parks and Wilderness Areas which have been specifically designated Class I 

under Section 162(a) of the CAA. There are no Class I areas near Redrock Canyon. 

The primary sources of air pollutants (PM10) affecting the watershed include traffic on 

unpaved roads, fire (both wildland fire and prescribed burning), and natural events such 

as windstorms. 

3.7.2 Environmental Consequences 

No Action

No change in air quality would result from taking no action. 

Proposed Action

Fugitive dust emissions could result from excavation and grading of alluvium within the 

stream channel at the barrier construction site. Dust emissions could be expected to vary 

depending on the level of activity, specific operation, and level of moisture encountered 

in floodplain soils. A direct effect to air quality would result from construction vehicles 

transporting employees and equipment over the unpaved FSR 138. Integration of ADEQ, 

Reclamation, and Forest Service BMPs for dust suppression would minimize the impact 

of particulate emissions on air quality. 

In addition, the operation of construction vehicles and equipment would produce tailpipe 

combustion products such as nitrogen oxides, carbon monoxide, sulfur oxides, and 

reactive organic gases which would locally degrade ambient air quality for very short 

periods of time. These emissions would not result in measurable changes in ambient 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 76
concentrations of regulated pollutants and a change in attainment status for the air quality 

region. 

Alternative A

Implementation of this alternative would not result in the fugitive dust emissions 

associated with the proposed construction of a fish barrier. Vehicle traffic during 

nonnative species removal and restocking of native species would be negligible. 

Cumulative Effects – Air Quality

Sources of atmospheric emissions from the action alternatives include vehicle traffic and 

equipment operation, both of which would release particulates and gaseous exhaust 

emissions to the atmosphere. The very small quantities of pollutants released would have 

negligible effect on local air quality for a very short period of time. Therefore, changes 

in ambient concentrations of regulated atmospheric pollutants would be unnoticeable, and 

cumulative impacts with other sources of pollutants in the airshed would not result. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 77
CHAPTER 4 – AGENCIES AND PERSONS CONSULTED 

List of Preparers 

Rob Clarkson, Bureau of Reclamation, Biologist 

Marci Donaldson, Bureau of Reclamation, Archaeologist 

John McGlothlen, Bureau of Reclamation, NEPA Specialist 

Andrea Campbell, USDA Forest Service, Coronado National Forest, NEPA Coordinator 

Bill Edwards, USDA Forest Service, Coronado National Forest, Range Conservationist 

Glenn Frederick, USDA Forest Service, Coronado National Forest, Biologist 

William Gillespie, USDA Forest Service, Coronado National Forest, Archaeologist 

Debby Kriegel, USDA Forest Service, Coronado National Forest, Landscape Architect 

Bob Lefevre, USDA Forest Service, Hydrologist 

Don Mitchell, Arizona Game and Fish Department, Biologist 

Sally Stefferud, Marsh & Associates, LLC, Biologist 

Other Contributors 

Ron Maes, USDA Forest Service, Southwestern Region, Biologist 

Tom Skinner, USDA Forest Service, Coronado National Forest, Biologist 

Amy Unthank, USDA Forest Service, Southwestern Region, Biologist 

Doug Duncan, U.S. Fish and Wildlife Service, Biologist 

Mima Falk, U.S. Fish and Wildlife Service, Botanist 

Mike Martinez, U.S. Fish and Wildlife Service, Biologist 

Jim Rorabaugh, U.S. Fish and Wildlife Service, Biologist 

Jeff Servoss, U.S. Fish and Wildlife Service, Biologist 

Abe Karam, Arizona State University, Biologist 

Paul Marsh, Arizona State University, Biologist 

Phil Rosen, University of Arizona, Biologist 

Jerome Stefferud, Biologist 

Henry Messing, Bureau of Reclamation, Biologist 

Jeff Riley, Bureau of Reclamation, Engineer 

Tom Jones, Arizona Game and Fish Department, Biologist 

Mike Sredl, Arizona Game and Fish Department, Biologist 

Ross Timmons, Arizona Game and Fish Department, Biologist 

Matt Killeen, The Nature Conservancy, Preserve Manager 

List of Agencies and Persons Contacted 

Libraries: 

Patagonia Public Library 

Chamber of Commerce: 

Nogales/Santa Cruz County Chamber of Commerce 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 78
Indian Communities: 

Ak-Chin Indian Community 

Fort Sill Apache Tribe 

Gila River Indian Community 

Mescalero Apache Tribe 

Salt River Pima-Maricopa Indian Community 

San Carlos Apache Tribe 

The Hopi Tribe 

Tohono O’odham Nation 

Pascua Yaqui Tribe 

Pueblo of Zuni 

White Mountain Apache Tribe 

Yavapai Apache Nation 

County Agencies: 

Santa Cruz County Board of Supervisors 

Santa Cruz County Health Services 

State Agencies: 

Arizona Department of Agriculture 

Arizona Department of Environmental Quality 

Arizona Department of Water Resources 

Arizona Game and Fish Department 

Arizona State Historic Preservation Office 

Federal Agencies: 

U.S. Fish and Wildlife Service 

U.S. Army Corps of Engineers 

U.S. Geological Survey 

Conservation and Environmental Organizations: 

American Rivers 

Arizona Riparian Council 

Center for Biological Diversity 

Desert Fishes Council 

Friends of Arizona Rivers 

Forest Guardians 

Sierra Club 

Sky Island Alliance 

The Nature Conservancy 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 79
Grazing Organizations: 

Arizona Cattle Growers Association 

Canelo Hills Coalition 

Other Organizations

Arizona Cooperative Extension Service 

Arizona People for the American Way 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 80
CHAPTER 5 - RELATED ENVIRONMENTAL LAWS/DIRECTIVES 

The following is a list of Federal laws, Executive Orders, and other directives that apply 

to the action alternatives discussed in this EA: 

The National Environmental Policy Act (NEPA) of 1969, as amended requires Federal 

agencies to evaluate the potential environmental consequences of major Federal actions. 

An action becomes “federalized” when it is implemented, wholly or partially funded, or 

requires authorization by a Federal agency. The intent of NEPA is to promote 

consideration of environmental impacts in the planning and decision-making process 

prior to project implementation. NEPA also encourages full public disclosure of the 

proposed action, accompanying alternatives, potential environmental effects, and 

mitigation. 

Scoping information was distributed to more than 53 individuals, organizations, and 

agencies on January 18, 2007. In addition, information on the proposed project was 

posted on CNF’s Schedule of Proposed Actions and Reclamation’s Phoenix Area Office 

web site in January 2007. 

The EA was prepared and distributed for 30-day public review in accordance with 

Reclamation guidelines and Forest Service regulations at 36 CFR 215. 

The National Forest Management Act (NFMA) of 1976, as amended requires the Forest 

Service, acting on behalf of the Secretary of Agriculture, to assess Forest lands and 

develop management plans based on multiple-use, sustained-yield principles for each unit 

of the Forest Service. The statute also requires the Forest Service to provide for the 

biological diversity of National Forests consistent with overall multiple-use objectives of 

the planning area and to maintain viable populations in the planning area. 

The Coronado Land and Resource Management Plan (LRMP) was adopted on August 4, 

1986, and has been amended 11 times. Forest planning is guided by the Code of Federal 

Regulations (CFR) at 36 CFR 219, which states that projects implemented after the 

LRMP is in place must be “consistent with the plan” (36 CFR 219.8(e)). The project was 

designed in conformance with the Coronado LRMP long-term goals and objectives on 

public lands for maintainenance of viable populations of native fishes and amphibians 

and work toward recovery of federally listed species. 

Forest Sensitive Species and Management Indicator Species (MIS) for the proposed 

project are identified in Section 3.2.9 of this document. Effects to these species are 

disclosed in this EA and in the Biological Evaluation and MIS Analysis prepared by the 

District Biologist. This analysis meets NFMA obligations for MIS under 36 CFR 

219.14(f). 

The Fish and Wildlife Coordination Act (FWCA) of 1958, as amended provides a 

procedural framework for the consideration of fish and wildlife conservation measures in 

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Native Fish Restoration in Redrock Canyon 81
Federal water resource development projects. Coordination with the FWS and State 

wildlife management agencies are required on all Federal water development projects. 

The barrier element of the proposed project is the result of ESA Section 7(a)(2) 

consultation between Reclamation and FWS. Coordination among Reclamation, FWS, 

and AGFD has been ongoing since the project’s inception. The FWS concluded that the 

current level of coordination among the agencies is sufficient to meet any regulatory 

needs required by the FWCA. 

The Endangered Species Act (ESA) of 1973, as amended provides protection for plants 

and animals that are currently in danger of extinction (endangered) and those that may 

become so in the foreseeable future (threatened). Section 7 of this law requires Federal 

agencies to ensure that their activities do not jeopardize the continued existence of 

threatened or endangered species or adversely modify designated critical habitat. 

Construction of a fish barrier in Redrock Canyon is part of the conservation measures 

being considered in an in-progress formal Section 7 consultation between Reclamation 

and the FWS. Recovery actions are a part of Reclamation’s fund transfer program under 

the 2001 biological opinion, and nonnative removal, native fish restoration, and stock 

tank management changes are, in part, terms and conditions of the incidental take 

statements of a 2002 biological opinion to the Forest Service. Possible effects to 

proposed and listed species and critical habitat resulting from project implementation 

were examined in a Biological Assessment prepared by Reclamation and the Forest 

Service and submitted to the FWS in August 2007. The Biological Assessment 

concluded the project may affect, and is likely to adversely affect, Gila topminnow, Gila 

chub, Sonora tiger salamander, and Chirichua leopard frog because some may be harmed 

by chemical and mechanical treatments of aquatic habitat, despite salvage efforts prior to 

the treatments. The proposed action may affect, but is unlikely to adversely affect, the 

lesser long-nosed bat. Despite possible adverse effects during implementation, the 

project is expected to have long-term, net benefits to native fish and amphibians by 

removing nonnative predatory fish and bullfrogs and preventing nonnative fish from 

reinvading stream habitat in Redrock Canyon. 

The Migratory Bird Treaty Act (MBTA) of 1918, as amended implements various 

treaties and conventions between the United States and Canada, Japan, Mexico, and the 

former Soviet Union for the protection of migratory birds. The MBTA prohibits the take, 

possession, import, export, transport, selling or purchase of any migratory bird, their 

eggs, parts or nests. 

Implementation of this project would not violate provisions of the MBTA. 

The Clean Air Act (CAA) of 1963, as amended requires any Federal entity engaged in an 

activity that may result in the discharge of air pollutants must comply with all applicable 

air pollution control laws and regulations (Federal, State, or local). It also directs the 

attainment and maintenance of National Ambient Air Quality Standards (NAAQS) for six 

different criteria pollutants including carbon monoxide, ozone, particulate matter, sulfur 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 82
oxides, oxides of nitrogen, and lead. Air quality in the project area is in attainment of 

NAAQS. 

Short-term construction emissions (particulate matter) associated with the proposed 

project would have localized and minor effects on air quality in the Redrock Canyon 

watershed. 

The Clean Water Act (CWA) of 1977, as amended strives to restore and maintain the 

chemical, physical, and biological integrity of the nation's waters by controlling discharge 

of pollutants. The basic means to achieve the goals of the CWA is through a system of 

water quality standards, discharge limitations, and permits. Section 404 of the CWA 

identifies conditions under which a permit is required for actions that result in placement 

of fill or dredged material into waters of the United States. In addition, a 401 water 

quality certification and 402 National Pollutant Discharge Elimination System (NDPES) 

permit are required for activities that discharge pollutants to waters of the U.S. The EPA 

has delegated responsibility to administer water quality certification and NPDES 

programs in Arizona to ADEQ. 

The discharge of dredged and fill material resulting from construction of the barrier 

requires a CWA Section 404 permit from the COE. Reclamation submitted an 

application to the COE for 404 permit coverage of all barriers that would be constructed 

pursuant to the 2001 CAP biological opinion. Reclamation received a conditional 401 

water quality certification and a 404 permit for these barriers on June 24 and October 30, 

2003, respectively. All special conditions of the 401 certification and 404 permit would 

be implemented. Coverage under the Section 402 Arizona Pollutant Discharge 

Elimination System General Permit for construction activities would be obtained prior to 

construction. 

The National Historic Preservation Act (NHPA) of 1966, as amended mandates all 

federally funded undertakings that have the potential to affect historic properties are 

subject to Section 106 of the NHPA. Federal agencies are responsible for the 

identification, management, and nomination to the National Register of Historic Places of 

cultural resources that could be affected by Federal actions. Consultation with the 

Advisory Council on Historic Preservation and the State Historic Preservation Office 

(SHPO) (or Tribal Historic Preservation Office) is required when a Federal action may 

affect cultural resources on, or eligible for inclusion on, the National Register. 

Archaeologists from Reclamation and CNF conducted a Class III Survey of the areas that 

would undergo ground-disturbing activities, including the access route, fish barrier 

locale, temporary laydown area, and staging area. No cultural resources were identified 

within the footprint of the proposed construction area. A finding of no historic properties 

affected was determined by Reclamation following the survey. Coronado National Forest 

indicated concurrence with the finding in an Inventory Standards and Accounting form, 

signed by Forest Archaeologist Mary Farrell and Forest Supervisor Jeanine Derby on 

December 8, 2006. The SHPO concurred with this determination on January 11, 2007. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 83
The Resource Conservation and Recovery Act (RCRA), as amended establishes 

thresholds and protocols for managing and disposing of solid waste. Solid wastes that 

exhibit the characteristic of hazardous waste, or are listed by regulation as hazardous 

waste, are subject to strict accumulation, treatment, storage, and disposal controls. 

The proposed project is not expected to generate hazardous waste as defined and 

regulated under RCRA. To minimize the possible impact of hazardous materials 

(petroleum, oil, and lubricants) used during construction, all equipment would be 

periodically inspected for leaks. Any significant leaks would be promptly corrected. 

Nonhazardous solid waste would be disposed of in accordance with State and Federal 

regulations at an approved landfill. Spills and disposal of contaminated media would be 

managed in accordance with State and Federal requirements. 

The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as amended requires 

all persons who apply pesticides classified as restricted use be certified, or that they work 

under the direct supervision of a certified applicator. Aquatic applicators must 

demonstrate a practical knowledge of the secondary effects that can be caused by 

improper application rates, incorrect formulations, and faulty application of restricted 

pesticides. Applicators must have a practical knowledge concerning potential effects on 

plants, birds, beneficial insects, and other organisms that may be present in aquatic 

environments. 

Piscicides have been used by fisheries managers in National Forests for stream and lake 

renovation projects since the 1930s. The U.S. Department of Agriculture Policy 

Regulation 9500-4 provides broad policy direction for fish and wildlife management in 

National Forests, including use of piscicides. Antimycin A is registered under the 

product name Fintrol. Antimycin A and rotenone are approved for use on Forest Service 

lands. Application of Antimycin A and rotenone in Redrock Canyon would be under the 

direction of a certified applicator in accordance with a Forest Service approved Safety 

Plan. The applicator would be charged with ensuring that all label and safety 

requirements are met. Piscicide applications would be consistent with relevant 

requirements of FIFRA. 

Executive Order 11988 (Floodplain Management) requires Federal agencies to avoid, 

where practicable alternatives exist, the short- and long-term adverse impacts associated 

with floodplain development. Federal agencies are required to reduce the risk of flood 

loss; minimize the impacts of floods on human safety, health, and welfare; and restore 

and preserve the natural and beneficial values served by floodplains in carrying out 

agency responsibility. 

The proposed project is necessary for the protection of the existing native fish community 

and potential recovery of listed species. Because the nature of the project requires minor 

construction in an active channel, no practicable alternative exists. Floodplain effects 

would be highly localized and minor. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 84
Executive Order 11990 (Wetlands) requires Federal agencies, in carrying out their land 

management responsibilities, to take action that would minimize the destruction, loss, or 

degradation of wetlands and take action to preserve and enhance the natural and 

beneficial values of wetlands. 

The proposed project would not adversely affect wetland functions or values. No 

physical loss of wetland habitat would occur. 

Executive Order 12898 (Environmental Justice) requires Federal agencies to identify and 

address, as appropriate, disproportionately high and adverse human health and 

environmental effects of their programs, policies, and activities on minority and lowincome populations. 

The proposed project area encompasses uninhabited National Forest land and potentially 

a minor portion of two private inholdings. No impact on low income or minority 

populations as defined by Executive Order 12898 would result. 

Secretarial Order 3175 (incorporated into Departmental Manual at 512 DM 2) requires 

that if any Department of the Interior agency actions might impact Indian trust assets, the 

agency must explicitly address those impacts in planning and decision documents, and 

the agency must consult with the tribal government whose trust resources are potentially 

affected by the Federal action. 

The proposed project would affect CNF land and potentially two private (non-Indian) 

inholdings. No Indian trust assets would be affected. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 85
CHAPTER 6 – LITERATURE CITED 

Adams, M.J., C.A. Pearl, and B.R. Bury. 2003. Indirect facilitation of an anuran 

invasion by nonnative fishes. Ecology Letters 6:343-351. 

AGFD (Arizona Game and Fish Department). 1996 (in prep). Wildlife of special 

concern in Arizona. Phoenix, AZ. 

Allen, Y., S. Kirby, G.H. Copp, and M. Brazier. 2006. Toxicity of rotenone to topmouth 

gudgeon Pseudorasbora parva for eradication of this nonnative species from a 

tarn in Cumbria, England. Fisheries Management and Ecology 13:337-340. 

Armour, C.L., D.A. Duff, and W. Elmore. 1991. The effects of livestock grazing on 

riparian and stream ecosystems. Fisheries 16(1):7-11. 

Baber, M.J. and K.J. Babbitt. 2004. Influence of habitat complexity on predator-prey 

interactions between the fish (Gambusia holbrooki) and tadpoles of Hyla squirella

and Gastrophryne carolinensis. Copeia 2004(1):173-177. 

Bagley, B.E., D.A. Hendrickson, F.J. Abarca, and S.D. Hart. 1991. Status of the 

Sonoran topminnow (Poeciliopsis occidentalis) and desert pupfish (Cyprinodon 

macularius) in Arizona. Arizona Game and Fish Department, Phoenix, AZ. 

Bahre, C.J. 1991. A legacy of change: historic human impact on vegetation in the 

Arizona borderlands. University of Arizona Press, Tucson, AZ. 

Belsky, A.J., A. Matzke, and S. Uselman. 1999. Survey of livestock influences on 

stream and riparian ecosystems in the western United States. Journal of Soil and 

Water Conservation 54:419-431. 

Bonar, S.A., L.L. Leslie, and C.E. Velez. 2004. Influence of species, size class, 

environment, and season on introduced fish predation on native fishes in the 

Verde River system, Arizona. University of Arizona, U.S. Geological Survey 

Cooperative Fish and Wildlife Research Unit,Tucson, AZ. 

Boyd, S.H. 1975. Inhibition of fish reproduction by Rana catesbeiana larvae. 

Physiological Zoology 48(3):225-234. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 86
Bradford, D.F., J.R. Jaeger, and R.D. Jennings. 2004. Population status and distribution 

of a decimated amphibian, the relict leopard frog (Rana onca). The Southwestern 

Naturalist 49(2):218-228. 

Bronmark, C., and P. Edenhamn. 1994. Does the presence of fish affect the distribution 

of tree frogs (Hyla arborea)? Conservation Biology 8(3):841-845. 

Brooks, J.E. 1986. Status of natural and introduced Sonoran topminnow (Poeciliopsis o. 

occidentalis) populations in Arizona through 1985. U.S. Fish and Wildlife 

Service, Albuquerque, NM. 

Brown, D.E. 1994. Biotic communities, southwestern United States and northwestern 

Mexico. University of Utah Press, Salt Lake City, UT. 

Burress, R.M. 1982. Effects of synergized rotenone on nontarget organisms in ponds. 

U.S. Fish and Wildlife Service Investigations in Fish Control 91:1-7. 

Capone, T.A., and J.A. Kushlan. 1991. Fish community structure in dry-season stream 

pools. Ecology 72(3):983-992. 

Carpenter, J. 2005. Competition for food between an introduced crayfish and two fishes 

endemic to the Colorado River basin. Environmental Biology of Fishes 72:335-

342. 

Carpenter, J., and C.C. McIvor. 2000. Effect of introduced crayfish on growth of two 

native fishes of the Colorado River basin. Proceedings of the Desert Fishes 

Council 32:24-25. 

Carpenter, J., and J.W. Terrell. 2006. Effectiveness of fish barriers and renovations for 

maintaining and enhancing populations of native southwestern fishes. Final 

Report to U.S. Fish and Wildlife Service, Arizona Ecological Service, Phoenix. 

Interagency Agreement 201814N756. 

Casterlin, M.E., and W.W. Reynolds. 1977. Aspects of habitat selection in the 

mosquitofish, Gambusia affinis. Hydrobiologia 55(2):125-127. 

Clarkson, R.W., P.C. Marsh, S.E. Stefferud, and J.A. Stefferud. 2005. Conflicts between 

native fish and nonnative sport fish management in the southwestern United 

States. Fisheries 30(9):20-27. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 87
Collins, J.P., and J. Snyder. 2002. Sonora tiger salamander (Ambystoma tigrinum 

stebbinsi) recovery plan. U.S. Fish and Wildlife Service, Albuquerque, NM. 

Cooke, R.U., and R.W. Reeves. 1976. Arroyos and environmental change in the 

American South-west. Clarendon Press, Oxford, England. 

Courtenay, W.R., Jr., and G.K. Meffe. 1989. Small fishes in strange places: a review of 

introduced poeciliids. Pp. 319-331 in Meffe, G.K. and F.F. Snelson, Jr., editors. 

Ecology and evolution of livebearing fishes (Poeciliidae). Prentice Hall, 

Engelwood Cliffs, NJ. 

Csargo, R. 2002. Management indicator species, analysis of effects. Redrock allotments 

allotment management plan (Seibold, Kunde, Crittenden, and Papago). In: Sierra 

Vista Ranger District. Environmental Assessment, 

Seibold/Kunde/Crittendon/Papago allotment management plans. U.S. Forest 

Service, Tucson, AZ. 

Danzer, S.J., R. Jemison, and D.P. Guertin. 2001. Riparian plant communities in the 

mountains of southeastern Arizona. The Southwestern Naturalist 46(2):191-199. 

Davis, G.P., Jr. 1986. Man and wildlife in Arizona. Arizona Game and Fish 

Department, Phoenix, AZ. 

Dawson, V.K., W.H. Gingerich, R.A. Davis, and P.A Gilderhus. 1991. Rotenone 

persistence in freshwater ponds: effects of temperature and sediment 

adsorption. North American Journal of Fisheries Management 11:226-231. 

Dawson, V.K., and C.S. Kolar. 2003. Integrated management techniques to control 

nonnative fishes. Final Report to U.S. Bureau of Reclamation, Phoenix Area 

Office, Interagency Agreement 01-AA-32-0040. U.S. Geological Survey, Upper 

Midwest Environmental Sciences Center, LaCrosse, WI. 

Dean, S.A. 1987. The Sonoran topminnow (Poeciliopsis occidentalis) and the 

mosquitofish (Gambusia affinis): a test of emigratory behavior. Unpublished 

Master’s Thesis, University of Arizona, Tucson. 

Degenhardt, W.G., C.W. Painter, and A.H. Price. 1996. Amphibians and reptiles of New 

Mexico. University of New Mexico Press, Albuquerque, NM. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 88
Desert Fishes Team. 2003. Report Number 1: Status of Federal and State listed warm 

water fishes of the Gila River basin, with recommendations for management. 

Desert Fishes Team, Phoenix, AZ. 

Desert Fishes Team. 2004. Report Number 2: Status of unlisted native fishes of the Gila 

River basin, with recommendations for management. Desert Fishes Team, 

Phoenix, AZ. 

Diamond, J.M. 1987. Extant unless proven extinct? Or, extinct unless proven extant? 

Conservation Biology 1(1):77-79. 

Dobyns, H.F. 1981. From fire to flood: historic human destruction of Sonoran Desert 

riverine oases. Ballena Press Anthropological Papers No. 20. 

Douglas, M.E., P.C. Marsh, and W.L. Minckley. 1994. Indigenous fishes of western 

North America and the hypothesis of competitive displacement: Meda fulgida

(Cyprinidae) as a case study. Copeia 1994(1):9-19. 

Dudley, R.K., and W.J. Matter. 2000. Effects of small green sunfish (Lepomis 

cyanellus) on recruitment of Gila chub (Gila intermedia) in Sabino Canyon, 

Arizona. The Southwestern Naturalist 45(1):24-29. 

EPA (U.S. Environmental Protection Agency). 2007. Attainment status information 

available at http://epa.gov/oar/oaqps/greenbk/ancl3.html. 

Fagan, W.F., P.J. Unmack, C. Burgess, and W.L. Minckley. 2002. Rarity, 

fragmentation, and extinction risk in desert fishes. Ecology 83(12):3250-3256. 

Fernandez, P.J., and P.C. Rosen. 1996. Effects of the introduced crayfish Oronectes 

virilis on native aquatic herpetofauna in Arizona. Arizona Game and Fish 

Department, Phoenix, AZ. 

Finlayson, B.J., R.A. Schnick, R.L. Cailteux, L. DeMong, W.D. Horton, W. McClary, 

C.W. Thompson, and G.J. Tichacek. 2000. Rotenone use in fisheries 

management. American Fisheries Society, Bethesda, MD. 

Fleming, T.H. 1997. Lesser long-nosed bat Leptonycteris curasoae yerbavuenae

recovery plan. U.S. Fish and Wildlife Service. Albuquerque, NM. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 89
Fonseca, J. 2002. Email of November 12, 2002, to Doug Duncan, U.S. Fish and Wildlife 

Service, re: notes from Redrock Canyon and Meadow Valley Wash. Tucson, AZ. 

Fontenot, L.W., G.P. Noblet, and S.G. Platt. 1994. Rotenone hazards to amphibians and 

reptiles. Herpetological Review 25(4):150-156. 

Foster, D. and D. Mitchell. 2005. Sonoita Creek fish surveys at Circle Z Ranch -- March 

19th, 2005. Arizona Game and Fish Department, Tucson, AZ. 

Frederick, G. 2005. Memo of July 19, 2005, to Bill Edwards re: removal of sediment 

from tanks on the San Rafael, O'Donnell, and Lone Mountain allotments. U.S. 

Forest Service, Sierra Vista, AZ. 

Fuller, P.L., L.G. Nico, and J.D. Williams. 1999. Nonindigenous fishes introduced into 

inland waters of the United States. American Fisheries Society Special 

Publication 27, Bethesda, MD. 

FWS (U.S. Fish and Wildlife Service). 1994. Final biological opinion on the 

transportation and delivery of Central Arizona Project water to the Gila River 

basin (Hassayampa, Agua Fria, Salt, Verde, San Pedro, middle and upper Gila 

rivers, and associated tributaries) in Arizona and New Mexico. 2-21-90-F-119. 

April 20, 1994, as amended June 22, 1995, May 6, 1998, July 15, 1998, January 

13, 2000, and June 30, 2000. Albuquerque, NM. 

FWS (U.S. Fish and Wildlife Service). 1998. Gila topminnow, Poeciliopsis occidentalis 

occidentalis, revised recovery plan. Albuquerque, NM. 

FWS (U.S. Fish and Wildlife Service). 2001a. 12-month finding for a petition to list the 

yellow-billed cuckoo (Coccyzus americanus) in the western continental United 

States. Federal Register 66(143):38611-38626. 

FWS (U.S. Fish and Wildlife Service). 2001b. Revised biological opinion on 

transportation and delivery of Central Arizona Project water to the Gila River 

basin (Hassayampa, Agua Fria, Salt, Verde, San Pedro, Middle and Upper Gila 

rivers, and associated tributaries) in Arizona and New Mexico and its potential to 

introduce and spread nonnative aquatic species. With April 2001 background 

information on the Central Arizona Project and nonnative aquatic species in the 

Gila River basin (excluding the Santa Cruz River subbasin). April 17, 2001. 

Phoenix, AZ. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 90
FWS (U.S. Fish and Wildlife Service). 2002. Biological opinion and conference opinion 

on continuation of livestock grazing on the Coronado National Forest 2-21-98-F399R1. USFWS. Phoenix, AZ. 

FWS (U.S. Fish and Wildlife Service). 2006a. Rana chiricahuensis localities - AZ (05 

Dec. 06). Phoenix, AZ. 

FWS (U.S. Fish and Wildlife Service). 2006b. Final environmental assessment: small 

scale exotic species removal in the San Rafael Valley, Arizona. Phoenix, AZ. 

FWS (U.S. Fish and Wildlife Service). 2007. Chiricahua leopard frog (Rana 

chiricahuensis) recovery plan. Albuquerque, NM. 

Gilderhus, P.A. 1972. Exposure times necessary for antimycin and rotenone to eliminate 

certain freshwater fish. Journal of the Fisheries Research Board of Canada 

29(2):199-202. 

Gilderhus, P.A., B.L. Berger, and R.E. Lennon. 1969. Field trials of antimycin A as a 

fish toxicant. FWS Investigations in Fish Control 27:1-21. 

Gray, L.J. 1981. Species composition and life histories of aquatic insects in a lowland 

Sonoran desert stream. The American Midland Naturalist 106(2):229-242. 

Gray, L.J., and S.G. Fisher. 1981. Postflood recolonization pathways of 

macroinvertebrates in a lowland Sonoran desert stream. The American Midland 

Naturalist 106:249-257. 

Grubb, J.C. 1972. Differential predation by Gambusia affinis on the eggs of seven 

species of anuran amphibians. The American Midland Naturalist 88(1):102-108. 

Hayes, M.P., and M.R. Jennings. 1986. Decline of ranid frog species in western North 

America: are bullfrogs (Rana catesbeiana) responsible? Journal of Herpetology 

20(4):490-509. 

Hedrick, P.W. 1995. Gene flow and genetic restoration: the Florida panther as a case 

study. Conservation Biology 9:996-1007. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 91
Hedrick, P.W., K.M. Parker, and R.N. Lee. 2001. Using microsatellite and MHC 

variation to identify species, ESUs and MUs in the endangered Sonoran 

topminnow. Molecular Ecology 10:1399-1412. 

Hendrickson, D.A., and W.L. Minckley. 1984. Cienegas -- vanishing climax 

communities of the American southwest. Desert Plants 6(3):131-175. 

Holycross, A.T., W.P. Burger, E.J. Nigro, and T.C. Brennan. 2006. Surveys for 

Thamnophis eques and Thamnophis rufipunctatus in the Gila River watershed of 

Arizona and New Mexico. Arizona Game and Fish Department, Mesa, AZ. 

Houf, L.J., and R.S. Campbell. 1977. Effects of antimycin A and rotenone on 

macrobenthos in ponds. U.S. Fish and Wildlife Service, Investigations in Fish 

Control No. 80. Washington, D.C. 

Hurlbert, S.H., J. Zedler, and D. Fairbanks. 1972. Ecosystem alteration by mosquitofish 

(Gambusia affinis) predation. Science 175:639-641. 

Ingvarsson, P.K. 2001. Restoration of genetic variation lost – the genetic rescue 

hypothesis. Trends in Ecology and Evolution 16:62-63. 

Johnson, J.E., M.G. Pardew, and M.M. Lyttle. 1993. Predator recognition and avoidance 

by larval razorback sucker and northern hog sucker. Transactions of the 

American Fisheries Society 122(6):1139-1145. 

Kane, A.S., R. Reimschuessel, and M.M. Lipsky. 1992. Effect of tadpoles on 

warmwater fish pond production. Fisheries 17(2):36-39. 

Kauffman, J.B., and W.C. Krueger. 1984. Livestock impacts on riparian ecosystems and 

streamside management implications...a review. Journal of Range Management 

37:430-438. 

Killeen, M. 2005. Monitoring report for native fish, Patagonia-Sonoita Creek Preserve, 

1991-2005. The Nature Conservancy, Patagonia, AZ. 

Kiner, L., A.A. Echelle, and W. Fisher. 2000. Effects of a chemical restoration project 

using antimycin-A on the fauna of Diamond Creek, Pecos County, Texas: year 

2000. Abstract No. 948742402-25. American Fisheries Society Annual Meeting, 

August 20-24, St. Louis, MO. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 92
Kruse, K.C., and M.G. Francis. 1977. A predation deterrent in larvae of the bullfrog, 

Rana catesbeiana. Transactions of the American Fisheries Society 106:248-252. 

Kupferberg, S.J. 1997. Bullfrog (Rana catesbeiana) invasion of a California river: the 

role of larval competition. Ecology 78:1736-1751. 

Lawler, S.P., D. Dritz, T. Strange, and M. Holyoak. 1999. Effects of introduced 

mosquitofish and bullfrogs on the threatened California red-legged frog. 

Conservation Biology 13(3):613-622. 

Lee, T.H., P.H. Derse, and S.D. Morton. 1971. Effects of physical and chemical 

conditions on the detoxification of antimycin. Transactions of the American 

Fisheries Society 100:13-17. 

Lemly, A.D. 1985. Suppression of native fish populations by green sunfish in first-order 

streams of Piedmont North Carolina. Transactions of the American Fisheries 

Society 114(5):705-712. 

Lennon, R.E., and B.L. Berger. 1970. A resume of field applications of antimycin A to 

control fish. U.S. Bureau of Sport Fisheries and Wildlife, Investigations in Fish 

Control No. 40, Washington, D.C. 

Lesser, B.R. 1970. The actue toxicities of antimycin A and juglone to selected aquatic 

organisms. Unpublished Master’s Thesis, University of Wisconsin, LaCrosse, 

WI. 

Lima, S.L. 1998. Nonlethal effects in the ecology of predator-prey interactions. 

BioScience 48:25-34. 

Logan, M.F. 2002. The lessening stream: an environmental history of the Santa Cruz 

River. University of Arizona Press, Tucson, AZ. 

Lowe, C.H. 1964. The vertebrates of Arizona, with a major section on Arizona habitats. 

University of Arizona Press, Tucson, AZ. 

Lydeard, C., and M.C. Belk. 1993. Management of indigenous fish species impacted by 

introduced mosquitofish: an experimental approach. The Southwestern Naturalist 

38(4):370-373. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 93
Marking, L.L., and T.D. Bills. 1975. Toxicity of potassium permanganate to fish and its 

effectiveness for detoxifying antimycin. Transactions of the American Fisheries 

Society 1975(3):579-583. 

Marsh, P.C., C.A. Pacey. 2005. Immiscibility of native and nonnative species. Pp. 59-

63. In: Restoring native fish to the lower Colorado River: interactions of native 

and nonnative fishes. U.S. Fish and Wildlife Service, Phoenix, AZ, and U.S. 

Bureau of Reclamation, Boulder City, NV. 

Marsh, P.C., C.A. Pacey, and W.L. Minckley. 1998. Resource use attributes of Colorado 

River fishes and implications for management of native and nonnative species. 

Proceedings of the Desert Fishes Council XXX:24. 

Marsh, P.C., J.A. Stefferud, and S.E. Stefferud. 2006. Fossil Creek fish monitoring. 

Annual report to U.S. Bureau of Reclamation, Phoenix Area Office, Contract 05-

CS-32-0180, May 8, 2006. 

McCoid, M.J., and P.W. Bettoli. 1996. Additional evidence for rotenone hazards to 

turtles and amphibians. Herpetological Review 27(2):70-71. 

Meffe, G.K. 1983. Ecology of species replacement in the Sonoran topminnow 

(Poeciliopsis occidentalis) and the mosquitofish (Gambusia affinis) in Arizona. 

Arizona State University, Tempe, AZ. 

Meffe, G.K., D.A. Hendrickson, W.L. Minckley, and J.N. Rinne. 1983. Factors resulting 

in decline of the endangered Sonoran topminnow Poeciliopsis occidentalis

(Atheriniformes: Poeciliidae) in the United States. Biological Conservation 

25(1983):135-159. 

Meronek, T.G., P.M. Bouchard, E.R. Buckner, T.M. Burri, K.K. Demmerly, D.C. Hatleli, 

R.A. Klumb, S.H. Schmidt, and D.W. Coble. 1996. A review of fish control 

projects. North American Journal of Fisheries Management 16(1):63-74. 

Minckley, W.L. 1969. Aquatic biota of the Sonoita Creek basin, Santa Cruz County, 

Arizona. The Nature Conservancy, Ecological Studies Leaflet No. 15. 

Washington, D.C. 

Minckley, W.L. 1973. Fishes of Arizona. Arizona Game and Fish Department, 

Phoenix, AZ. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 94
Minckley, W.L. 1991. Native fishes of the Grand Canyon region: an obituary? Pp. 124-

177 in Colorado River ecology and dam management. Proceedings of a 

symposium May 24-25, 1990, Santa Fe, New Mexico. National Academy Press, 

Washington, D.C. 

Minckley, W.L. 1995. Translocation as a tool for conserving imperiled fishes: 

experiences in western United States. Biological Conservation 72(1995):297-309. 

Minckley, W.L. 1999. Ecological review and management recommendations for 

recovery of the endangered Gila topminnow. Great Basin Naturalist 59(3):230-

244. 

Minckley, W.L., J.E. Deacon, P.C. Marsh, W.J. Matthews and P.B. Moyle. 1997. 

Sustainability of western native fish resources. Pp. 63-79 in W.L.Minckley, 

editor. Aquatic ecosystems symposium: a report to the Western Water Policy 

Review Advisory Committee. Tempe, AZ. 

Minckley, W.L., and P. Mihalick. 1981. Effects of chemical treatment for fish 

eradication on stream-dwelling invertebrates. Journal of the Arizona-Nevada 

Academy of Science 16:79-82. 

Minckley, W.L., R.R. Miller, and S.M. Norris. 2002. Three new pupfish species, 

Cyprinodon (Teleostei, Cyprinodontidae), from Chihuahua, Mexico, and Arizona, 

USA. Copeia 2002(3):687-705. 

Minckley, W.L., J.N. Rinne, and J.E. Johnson. 1977. Status of the Gila topminnow and 

its co-occurrence with mosquitofish. USDA Forest Service Research Paper RM198. Ft. Collins, CO. 

Mitchell, D. 2002. Redrock Canyon stock tank and stream survey. Final Report, 

September 2002. Arizona Game and Fish Department, Tucson. 

Morrison, B.R.S. 1979. An investigation into the efects of the piscicide antimycin A on 

the fish and invertebrates of a Scottish stream. Fisheries Management 10:111-

122. 

Moyle, P.B. 2002. Inland fishes of California. University of California Press, Berkeley. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 95
Mueller, G., J. Carpenter, and D. Thornbrugh. 2006. Bullfrog tadpole (Rana 

catesbeiana) and red swamp crayfish (Procambarus clarki) predation on early life 

stages of endangered razorback sucker. The Southwestern Naturalist 51(2):258-

261. 

Mueller, G.A., and P.C. Marsh. 2003. Lost, a desert river and its native fishes: a 

historical perspective of the lower Colorado River. U.S. Geological Survey 

Information and Technology Report USGS/BRD/ITR--2002-0010, Denver, CO. 

NRCS (Natural Resources Conservation Service). 2007. Web soil survey available at 

http://websoilsurvey.nrcs.usda.gov/app/. 

Pacey, C.A., and P.C. Marsh. 1998. Resource use by native and nonnative fishes of the 

lower Colorado River: literature review, summary, and assessment of relative 

roles of biotic and abiotic factors in management of an imperiled indigenous 

ichthyofauna. Final report to U.S. Bureau of Reclamation, Lower Colorado 

Regional Office, Agreement No. 7-MT-30-R0012. Arizona State University, 

Tempe. 

Platts, W.S. 1991. Livestock grazing. Pages 389-423 in W.R. Meehan, editor. 

Influences of forest and rangeland management. American Fisheries Society 

Special Publication 19. 

Platts, W.S., and R.F. Raleigh. 1984. Impacts of grazing on wetlands and riparian 

habitat. Pages 1105-1117 in Developing strategies for rangeland management. 

Westview Press, Boulder, Colorado. 

Pope, G.L., P.D. Rigas, and C.F. Smith. 1998. Statistical summaries of streamflow data 

and characteristics of drainage basins for selected streamflow-gauging stations in 

Arizona through water year 1996. U.S. Geological Survey, Water Resources 

Investigations Report 98-4225. Tucson, AZ. 

Propst, D.L., and K.R. Bestgen. 1991. Habitat and biology of the loach minnow, 

Tiaroga cobitis, in New Mexico. Copeia 1991(1):29-38. 

Rinne, J.N., B. Rickel, and D.A. Hendrickson. 1980. A new Gila topminnow locality in 

southern Arizona. USDA Forest Service, Research Note RM-382. Ft. Collins, 

CO. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 96
Rodgeveller, C. 2000. Portions of a report by Cara Rodgevell for Dr. Peter Reinthal re: 

sampling of Sonoita Creek above Patagonia Dam. University of Arizona, Tucson. 

Rogge, A.E., D.L. McWatters, and M.E.R.P. Keane. 1995. Raising Arizona's dams: 

daily life, danger, and discrimination in the dam construction camps of central 

Arizona, 1890s-1940s. University of Arizona, Tucson. 

Rosen, P.C., and C.R. Schwalbe. 1988. Status of the Mexican and narrow-headed 

gartersnake (Thamnophis eques megalops) and (Thamnophis rufipunctatus 

rufipunctatus) in Arizona. Report to U.S. Fish and Wildlife Service. Arizona 

Game and Fish Department, Phoenix. 

Rosen, P.C., C.R. Schwalbe. 1995. Bullfrogs: introduced predators in southwestern 

wetlands. Pp. 452-453 in LaRoe, E.T., Farris: G.S., C.E. Puckett, P.D. Doran, 

and M.J. Mac, editors. Our living resources: a report to the nation on the 

distribution, abundance, and health of U.S. plants, animals, and ecosystems. U.S. 

Department of the Interior, National Biological Service, Washington, D.C. 

Rosen, P.C., and C.R. Schwalbe. 2002. Widespread effects of introduced species on 

reptiles and amphibians in the Sonoran Desert region. Pp. 220-240. In: B.

Tellman, editor. Invasive exotic species in the Sonoran region. University of 

Arizona Press, Tucson. 

Rosen, P.C., C.R. Schwalbe, D.A. Parizek, Jr., P.A. Holm, and C.H. Lowe. 1995. 

Introduced aquatic vertebrates in the Chiricahua region: effects on declining 

native ranid frogs. Pp. 251-261 in DeBano, L.F., G.J. Gottfried, R.H. Hamre, 

C.B. Edminster, P.F. Ffolliott, and A. Ortega-Rubio, editors. Biodiversity and 

management of the Madrean archipelago: the sky islands of southwestern United 

States and northwestern Mexico. September 19-23, 1994, Tucson, AZ. US Forest 

Service Rocky Mountain Forest and Range Experiment Station General Technical 

Report RM-GTR-264. Ft. Collins, CO. 

Rosen, P.C., J.E. Wallace, and C.R. Schwalbe. 2001. Resurvey of the Mexican 

gartersnake (Thamnophis eques) in southeastern Arizona. University of Arizona, 

Tucson. 

Schnick, R. A. 1974. A review of the literature on the use of rotenone in fisheries. 

USDI Fish and Wildlife. La Crosse, WI. 

Scott, J.E. 1995. Memo: Location of frogs, possibly leopard frogs. Arizona Game and 

Fish Department, Tucson. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 97
Sellers, W.D., and R.H. Hill. 1974. Arizona climate. University of Arizona Press, 

Tucson. 

Simons, L.H. 1987a. Field Notes May 1986-Dec. 1987. Arizona Game and Fish 

Department, Phoenix. 

Simons, L.H. 1987b. Status of the Gila topminnow (Poeciliopsis occidentalis 

occidentalis) in the United States. Arizona Game and Fish Department, Phoenix. 

Sloat, M.R. 1999. The use of artificial migration barriers in the conservation of resident 

stream salmonids. Montana Cooperative Fishery Research Unit, Montana State 

University, Bozeman. 

Snow, H.E. 1974. Notes on the zooplankton and benthos of Rush Lake, Douglas 

County, six years after application of antimycin. Wisconsin Department of 

Natural Resources, Technical Bulletin No. 79, Madison. 

Snyder, J.D. 2006. Ecology, management, and intellectual history of native and 

introduced species. Unpublished Master’s Thesis, Arizona State University, 

Tempe. 

Stefferud, J.A. 1989. Memo: Gila topminnow, Redrock Canyon. U.S. Forest Service. 

Phoenix, AZ. 

Stefferud, J.A. and D.L. Propst. 1996. A lightweight, constant-flow device for 

dispensing liquid piscicides into streams in remote areas. North American Journal 

of Fisheries Management 16(1):228-230. 

Stefferud, J.A., and S.E. Stefferud. 1994. Status of Gila topminnow and results of 

monitoring the fish community in Redrock Canyon, Coronado National Forest, 

1979-1993. Pp. 361-369 in P.F. Ffolliott, editor. Biodiversity and management 

of the Madrean Archipelago: the sky islands of southwestern United States and 

Northwestern Mexico. Sept. 19-23, 1994. Tucson, AZ. U.S. Forest Service 

Rocky Mountain Forest and Range Experiment Stateion, General Technical 

Report Rm-GTR264. Ft. Collins, CO. 

Stefferud, J.A., and S.E. Stefferud. 2004. Aquatic and riparian surveys of selected 

stream courses on Sierra Vista and Nogales Ranger Districts, Coronado National 

Forest, Cochise and Santa Cruz Counties, Arizona. Final Report to U.S. Forest 

Service, Agreement 11CS110305-17-032. Arizona State University, Tempe. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 98
Stefferud, S.E. 1977. Aquatic invertebrate monitoring: brown trout control program, 

South Fork Kern River, September 1976. California Fish and Game Department, 

Bishop. 

Stringer, J.E. Brooks, and W. Hayes. 1985. Gila topminnow survey form, Redrock 

Canyon, August 1, 1985. Arizona Game and Fish Department, Phoenix. 

USFS (Forest Service). 1986. Coronado National Forest Plan. Southwestern Region, 

Albuquerque, NM. 

USFS (Forest Service). 1999. Southwestern Region Sensitive Species List, Regional 

Forester memorandum to Forest Supervisors, Albuquerque, NM. 

USFS (Forest Service). 2003. Environmental assessment: Seibold/Kunde/Crittendon, 

Papago allotment management plans. Coronado National Forest. Tucson, AZ. 

USFS (Forest Service). 2006. Livestock management and Chiricahua leopard frog and 

stockpond and aquatic habitat management and maintenance guidelines for the 

Chiricahua leopard frog on the Coronado National Forest. Tucson, AZ. 

USFS (Forest Service) and Reclamation. 2007. Biological Assessment. Redrock 

Canyon native fish restoration project. Sierra Vista Ranger District, Coronado 

National Forest, and Bureau of Reclamation, Phoenix Area Office. Tucson and 

Phoenix, AZ. 

van Loben Sels, R.C., J.D. Congdon, and J.T. Austin. 1994. Aspects of the life history 

and ecology of the Sonoran mud turtle in southeastern Arizona. Pp. 262-266. In: 

Biodiversity and Management of the Madrean Archipelago: the sky islands of the 

southwestern United States and northwestern Mexico. September 19-23, 1994. 

U.S. Forest Service Rocky Mountain Forest and Range Experiment Station 

General Technical Report RM-GTR-264. Tucson, AZ. 

Vezina, C. 1967. Antimycin A, a teleocidal antibiotic. Chemotherapy 1966:757-766. 

Voeltz, J.B., and R.H. Bettaso. 2003. 2003 status of the Gila topminnow and desert 

pupfish in Arizona. Arizona Game and Fish Department, Phoenix. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 99
Waite, T.E., J. Vucetich, T. Saurer, M. Kroninger, E. Vaughn, K. Field, and S. Ibarguen. 

2005. Minimizing extinction risk through genetic rescue. Animal Biodiversity 

and Conservation 28(2):121-130. 

Walker, C.R., R.E. Lennon, and B.L. Berger. 1964. Preliminary observations on the 

toxicity of antimycin A to fish and other aquatic animals. Bureau of Sport 

Fisheries and Wildlife Circular 186 Investigations in Fish Control. Washington, 

D.C. 

Weedman, D.A. 1994. Memo to Kirk Young re: Bog Hole watershed survey results. 

Arizona Game and Fish Department. Phoenix. 

Weedman, D.A. 2000. Gila topminnow, Poeciliopsis occidentalis occidentalis, revised 

recovery plan. June 2002. U.S. Fish and Wildlife Service, Albuquerque, NM. 

Weedman, D.A., A.L. Girmendonk, and K.L. Young. 1996. Status review of Gila chub, 

Gila intermedia, in the United States and Mexico. Technical Report 91, Arizona 

Game and Fish Department, Phoenix. 

Weedman, D.A., P.J. Sponholtz, and S. Hedwall. 2005. Fossil Creek native fish 

restoration project. Final project report, November 2005. U.S. Bureau of 

Reclamation, Arizona Game and Fish Department, U.S. Fish and Wildlife 

Service. Phoenix, AZ. 

Weedman, D.A., and K.L. Young. 1997. Status of the Gila topminnow and desert 

pupfish in Arizona. Arizona Game and Fish Department, Phoenix. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 100
Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 101

APPENDIX A 

Location Records for Native and Nonnative Aquatic Vertebrates 

in the Redrock Canyon Watershed and Vicinity 
Table A-1. Location records for native and nonnative species. 

SPECIES LOCATION IN PROJECT AREA? LATEST RECORD 

Unnamed tributary from north to Oak Grove Spring Canyon in west 1/2 Sec. 35 

yes 1997 

Unnamed tank in north fork Oak Grove Spring Canyon (Oak Tank) 

yes 2003 

Meadow Valley Tank & unnamed tank downstream (Hudson Tank) 

yes 1982 

Harshaw Creek near Harshaw town site no 1998 Sonoita Creek near Patagonia no 1945 Monkey Spring no 2000 Flower Tank in Western Canyon no 1979 O’Donnell Canyon no 2000 

Chiricahua leopard frog Rana chiricahuensis 

San Rafael Valley tanks no 1999 Unnamed tank in unnamed tributary to Lampshire Canyon (Sink Hole Tank) 

yes possible 

record in 2002 

Unnamed tank in north fork Oak Grove Spring Canyon (Oak Tank) 

yes 2003 

Meadow Valley Tank & unnamed tank downstream (Hudson Tank) 

yes 1996 

Bog Hole no 1996 

Sonora tiger salamander Ambystoma tigrinum stebbinsi

San Rafael Valley no 2006 Lampshire yes 2001 Oak Grove Spring Canyon yes 2002 Redrock Canyon Lampshire to Red Bank Well (inc. Gate Spring) 

yes 2001 

Redrock Canyon in Cott Tank Exclosure yes 2003 Cott Tank drainage below barriers yes 2005 Cott Tank drainage above barriers Martin Tank yes 2002 Down Under Tank yes 2002 Santa Cruz River in San Rafael Valley (US only) no 2005 

Sonora mud turtle Kinosternon sonoriense

Sheehy Spring no 2005 

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
SPECIES LOCATION IN PROJECT AREA? LATEST RECORD 

Gate Spring yes 1989 Red Bank Well yes 1990 

Black-necked gartersnake Thamnophis cyrtopsis 

Lampshire Canyon yes 2001 Redrock Canyon – Cott Tank drainage Yes Questionable 

records 1989, 2006 

O’Donnell Creek at Finley Tank no 2000 Bog Hole No 1986 Sheehy Spring no 2000 

Mexican gartersnake Thamnophis eques

Santa Cruz River in San Rafael Valley no 2000 Redrock Canyon below Falls yes 2002 Sonoita Creek near Patagonia no 2005 

Desert sucker Pantosteus clark

Santa Cruz River in the San Rafael Valley no 1995 Redrock Canyon below Falls yes 2003 Pig Camp Spring yes 2001 Oak Grove Spring Canyon yes 1987 Unnamed tributary from north to Oak Grove Spring Canyon in (west side Sec. 35) 

yes 1987 

Lampshire Canyon yes 2001 Redrock Canyon, Falls to Lampshire Canyon yes 2001 Redrock Canyon Lampshire to Red Bank Well (inc. Gate Spring) 

yes 2001 

Redrock Canyon in Cott Tank Exclosure yes 2002 Cott Tank drainage below barriers yes 2005 Cott Tank drainage above barriers yes 1995 Santa Cruz River in San Rafael Valley (US only) no 1993 Sheehy Spring no 1987 Monkey Spring no 2005 Sonoita Creek near Patagonia no 2005 Harshaw Creek no Reintro, 1982 

Gila topminnow Poeciliopsis occidentalis 

O’Donnell Canyon no 2004 

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
SPECIES LOCATION IN PROJECT AREA? LATEST RECORD 

O’Donnell Canyon no 2004 Monkey Spring no 1969 

Gila chub Gila intermedia

Sheehy Spring no 2005 

Speckled dace Redrock Canyon below Falls yes 2001 Rhinichthys osculus Sonoita Creek near Patagonia no 2005 

Redrock Canyon below Falls yes 2003 Pig Camp Spring yes 2002 Oak Grove Spring Canyon yes 2001 Unnamed tributary from north to Oak Grove Spring Canyon in (west side Sec. 35) 

yes 2002 

Lampshire Canyon yes 1992 Redrock Canyon Falls to Lampshire Canyon yes 2001 Redrock Canyon Lampshire to Red Bank Well (inc. Gate Spring) 

yes 2001 

Redrock Canyon in Cott Tank Exclosure yes 1993 Redrock Canyon above Cott Tank drainage yes 1989 Cott Tank drainage below barriers yes 1994 Harshaw Canyon no 2002 Cottonwood Spring no 2001 Sonoita Creek near Patagonia no 2005 O’Donnell Canyon No 2004 

Longfin dace Agosia chrysogaster

Santa Cruz River in the San Rafael Valley No 2002 Oak Grove Spring Canyon, SE Fork yes 2002 MOak Grove Spring Canyon, middle tributary to North Fork yes 2002 MLampshire Canyon yes 2001 SRedrock Canyon, Gate Spring yes 2004 SRedrock Canyon below confluence with Cott Tank drainage yes 2000 SCott Tank drainage below barriers yes 2006 SCott Tank drainage above barriers yes 2004 S

Bullfrog Rana catesbeiana 

Down Under Tank yes 1996 S

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
SPECIES LOCATION IN PROJECT AREA? LATEST RECORD 

Unnamed tank in east fork of Kennedy Spring tributary to Redrock Canyon (First Tank) 

yes 2006 S

Unnamed tank in unnamed tributary to Lampshire Canyon (Sink Hole Tank) 

yes 2002 M

Unnamed tank in unnamed tributary to Oak Grove Spring Canyon in east 1⁄2 Sec. 35 = Dry Tank 

yes 2002 M

Meadow Valley Tank & unnamed tank downstream (Hudson Tank) 

yes 2002 M

Bog Hole yes 2002 FSonoita Creek near Patagonia yes 2006 K

c

Redrock Canyon below Falls yes 2002 SOak Grove Spring Canyon yes 1990 SLampshire Canyon yes 1987 SRedrock Canyon, Falls to Lampshire Canyon yes 2001 SRedrock Canyon, Lampshire to Red Bank Well (inc. Gate Spring) 

yes 2001 S

Redrock Canyon in Cott Tank Exclosure yes 2006 SCott Tank drainage below barriers yes 2006 SCott Tank drainage above barriers yes 2002 SRedrock Canyon above confluence with Cott Tank drainage yes 1988 SDown Under Tank yes 1996 SUnnamed tank in east fork of Kennedy Spring tributary to Redrock Canyon (First Tank) 

yes 2006 G

c

Cott Tank yes 1986 SLampshire Tank yes 1985 SSonoita Creek near Patagonia no 2000 RHarshaw Canyon no 2002 S

2

Bog Hole no 1997 SSanta Cruz River in San Rafael Valley no 2005 S

Mosquitofish Gambusia affinis 

Sheehy Spring no 2005 S

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
ish Restoration in Redrock Canyon 

SPECIES LOCATION IN PROJECT 

AREA? 

LATEST RECORD 

S

Redrock Canyon in Cott Tank exclosure yes 1987 SRedrock Canyon above confluence with Cott Tank drainage yes 1987 SCott Tank drainage above barrier yes 1996 SLampshire Tank yes 1985 BDown Under Tank yes 1987 SO’Donnell Canyon no 2002 

(renovated) 

S2

Sonoita Creek near Patagonia no 2005 KBog Hole no 1997 S

Green sunfish Lepomis cyanellus 

Santa Cruz River in San Rafael Valley no 2005 SRedrock Canyon Lampshire to Red Bank Well (inc. Gate Spring) 

yes 1985 B

Redrock Canyon above confluence with Cott Tank drainage yes 1987 SRedrock Canyon below confluence with Cott Tank drainage yes 1987 SCott Tank drainage below barriers yes 1995 WCott Tank drainage above barriers yes 1993 SDown Under Tank yes 1987 SMeadow Valley Tank yes 1988 SBog Hole yes 1994 WSonoita Creek near Patagonia no 1994 G

Largemouth bass Micropterus salmoides 

Santa Cruz River in San Rafael Valley no 2000 SRedrock Canyon upstream of Redrock Well yes 1990 SCott Tank drainage below barrier yes 1993 SCott Tank drainage above barrier yes 1996 SUnnamed tank in east fork of Kennedy Spring tributary to Redrock Canyon (First Tank) 

yes 1987 S

Cott Tank yes 1985 SDown Under Tank yes 1986 SLampshire Tank yes 1985 B

Bluegill 

Lepomis macrochirus 

Bog Hole no 1994 W

Draft Environmental Assessment Native F
Figure A-1. Locations of bullfrog. 

Figure A-2. Locations of mosquitofish 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 107
Figure A-3. Locations of largemouth bass, green sunfish, and bluegill. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 108
APPENDIX B 

Distribution of Native and Nonnative Fishes in the Gila River Basin 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 109
Table B-1. Historical distributions, known extirpated populations, known occupied streams, and 

recommended replication sites for Federal- or State-listed fishes of the Gila River basin, 

excluding trouts. 

Species Historical Distribution

Known Extirpated 

Populations

Known Occupied Streams 

(exclusive of restoration sites)

Cyprinodon arcuatus (Ex) 

Santa Cruz (Monkey 

Spring) pupfish 

Low-elevation streams, springs, 

cienegas, backwaters, and 

margins of larger rivers in the 

Santa Cruz River basin 

Santa Cruz River 

Monkey Spring (Santa Cruz) 

Sonoita Creek (Santa Cruz) 

Species is extinct 

Cyprinodon macularius (E) 

Desert pupfish 

Low-elevation streams, springs, 

cienegas, backwaters, and 

margins of larger rivers in the 

Gila River basin, including all 

major subbasins except the 

Santa Cruz River basin

Agua Fria River 

Gila River 

Hassayampa River 

Salt River 

San Pedro River 

Verde River

Gila River basin populations 

extirpated 

Gila elegans (E) 

Bonytail 

Low-intermediate elevation 

mainstem reaches of the Gila 

and Salt rivers 

Gila River 

Salt River 

Gila River basin populations 

extirpated 

 

Gila intermedia (PE) 

Gila chub 

Upper reaches of small-middlesized streams of the Gila River 

basin, including all major 

subbasins 

Agua Fria River (Gila) 

Queen/Arnett creeks (Gila) 

San Simon River (Gila) 

Cave Creek/Seven Springs (Salt) 

Fish Creek (Salt) 

San Pedro River 

Binghampton Pond (San Pedro) 

Garden Canyon (San Pedro) 

Turkey Creek (San Pedro) 

Santa Cruz River 

Monkey Spring (Santa Cruz) 

Big Chino Wash (Verde) 

Indian Creek (Agua Fria) 

Larry Creek (Agua Fria) 

Little Sycamore Creek (Agua Fria) 

Lousy Canyon (Agua Fria) 

Silver Creek (Agua Fria) 

Sycamore Creek (Agua Fria) 

Bonita Creek (Gila) 

Eagle/East Eagle Creek (Gila) 

Mineral Creek/Devil’s Canyon (Gila) 

Turkey Creek, NM (Gila) 

San Carlos River 

Blue River (San Carlos) 

Dix Creek (San Francisco) 

Harden Cienega (San Francisco) 

San Pedro River, Mexico 

Babocomari River (San Pedro) 

Hot Springs/Bass Canyon (San 

Pedro) 

Los Fresnos River, Mexico (San 

Pedro) 

O’Donnell Creek (San Pedro) 

Post/Freeman canyons (San Pedro) 

Redfield Canyon (San Pedro) 

Cienega Creek (Santa Cruz) 

Empire Gulch (Santa Cruz) 

Mattie Canyon (Santa Cruz) 

Sabino Canyon (Santa Cruz) 

Sheehy Spring (Santa Cruz) 

Red Tank Draw (Verde) 

Spring Creek (Verde) 

Walker Creek (Verde) 

Williamson Valley Wash (Verde) 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 110
Species Historical Distribution Known Extirpated 

Populations

Known Occupied Streams 

(exclusive of restoration sites)

Gila nigra (W/P, S) 

Headwater chub 

Middle to headwater reaches of 

middle-sized tributary streams in 

the Verde, Tonto, San Carlos, 

and upper Gila River (NM) 

subbasins 

Beaver Creek (E Fk Gila River) 

Taylor Creek (E Fk Gila River) 

Christopher Creek (Tonto) 

Horton Creek (Tonto) 

Sharp Creek (Tonto) 

Rye Creek (Tonto) 

Dry Beaver Creek (Wet Beaver) 

Gila River, upper 

San Carlos River 

Ash Creek (San Carlos) 

Tonto Creek 

Buzzard Roost (Tonto) 

Gordon Creek (Tonto) 

Gunn Creek (Tonto) 

Haigler Creek (Tonto) 

Marsh Creek (Tonto) 

Rock Creek (Tonto) 

Spring Creek (Tonto) 

Deadman Creek (Verde) 

East Verde River (Verde) 

Fossil Creek (Verde) 

Webber Creek (Verde) 

Wet Bottom Creek (Verde) 

Gila robusta (S) 

Roundtail chub 

Middle-sized to larger streams 

of the Gila River basin, 

including all major subbasins 

except the Santa Cruz River 

basin 

Boneyard Creek (E Fk Black) 

Gila River, middle reach (AZ) 

Salt River, upper reach 

San Francisco River (Gila) 

Blue River (San Francisco) 

San Pedro River 

N Fk White River (White) ? 

Gila River, upper 

Eagle Creek (Gila) 

Salt River, lower reach 

Salt River Project canals 

Black River (Salt) 

Canyon Creek (Salt) 

Carrizzo Creek (Salt) 

Cedar Creek (Salt) 

Cherry Creek (Salt) 

Cibeque Creek (Salt) 

Corduroy Creek (Salt) 

Salome Creek (Salt) 

White River (Salt) ? 

Aravaipa Creek and tributaries (San 

Pedro) 

Verde River 

Fossil Creek (Verde) 

Oak Creek (Verde) 

West Clear Creek (Verde) 

Wet Beaver Creek (Verde) 

Meda fulgida (T) 

Spikedace 

Low-intermediate elevation 

streams in the Gila River basin, 

including all major subbasins 

except the Santa Cruz River 

basin 

Agua Fria River 

Salt River 

San Francisco River 

San Pedro River, US and 

Mexico 

Eagle Creek (Gila) 

Gila River, Middle Fork 

Gila River, West Fork 

Gila River, East Fork 

Gila River, middle reach (AZ) 

Mangus Creek (Gila) 

Aravaipa Creek (San Pedro) 

Verde River 

Plagopterus argentissimus 

(E) 

Woundfin 

Low-elevation streams in the 

Gila River basin, including all 

major subbasins except the 

Santa Cruz River basin 

Gila River 

Salt River 

Verde River 

Gila River basin populations 

extirpated 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 111
Species Historical Distribution Known Extirpated 

Populations

Known Occupied Streams 

(exclusive of restoration sites)

Poeciliopsis occidentalis (E) 

Gila topminnow 

Low-intermediate elevation 

streams, springs, cienegas, 

backwaters, and margins of 

larger rivers in the Gila River 

basin, including all major 

subbasins 

Gila River 

Ash Creek, North Fork (Gila) 

Salt Creek (Gila) 

San Simon River (Gila) 

San Carlos River (Gila) 

Salt River 

Tonto Creek (Salt) 

Frisco Hot Spring (San 

Francisco) 

San Pedro River 

Arivaca Creek (San Pedro) 

Cocio Wash (Santa Cruz) 

Potrero Creek (Santa Cruz) 

Sabino Canyon (Santa Cruz) 

Sheehy Spring (Santa Cruz) 

Tanque Verde Creek (Santa 

Cruz) 

Verde River 

Other unnamed waters 

Bylas Springs (Gila) 

Santa Cruz River, upper reach (US 

and Mexico) 

Cienega Creek (Santa Cruz) 

Cottonwood Spring (Santa Cruz) 

Monkey Spring (Santa Cruz) 

Sharp Spring (Santa Cruz) 

Sonita Creek complex (Santa Cruz) 

 Redrock Canyon 

 Fresno Canyon 

 Coal Mine Canyon 

 Sonoita Creek 

Ptychocheilus lucius (E) 

Colorado squawfish 

Low-intermediate elevation 

streams in the Gila River 

basin, including all major 

subbasins except the Santa 

Cruz River basin 

Gila River 

Salt River 

San Pedro River 

Verde River 

Gila River basin populations 

extirpated 

Tiaroga cobitis (T) 

Loach minnow 

Low-high elevation streams 

in the Gila River basin, 

including all major subbasins 

except the Santa Cruz River 

basin 

Gila River (AZ portion) 

Salt River 

San Pedro River, US and 

Mexico 

Verde River 

Aravaipa Creek and tributaries (San 

Pedro) 

Black River, North Fork of East Fork 

(Salt) 

Blue River, and tributaries (San 

Francisco) 

Eagle Creek (Gila) 

Gila River, Middle Fork 

Gila River, West Fork 

Gila River, East Fork 

San Francisco River and NM 

tributaries 

White River, North Fork (Salt) 

White River (Salt) 

White River, East Fork (Salt) 

Xyrauchen texanus (E) 

Razorback sucker 

Low-intermediate elevation 

streams in the Gila River 

basin, including all major 

subbasins except the Santa 

Cruz River basin 

Gila River 

Salt River 

San Pedro River 

Verde River 

Gila River basin populations 

extirpated 

T = threatened, E = endangered, S = State listed, Ex = Extinct, PE = proposed endangered; W/P = warranted but 

precluded finding on petition to list. Parentheticals denote major subdrainage affiliations, question marks denote 

uncertain status. 

 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 112
Table B-2. Partial list of established15 nonnative fishes in the Gila River basin. 

STATUS SPECIES DISTRIBUTION TREND 

Family Atherinidae - 

silversides 

Inland silverside, Menidia 

beryllina

L R 

Threadfin shad, Dorosoma 

petenense 

Family Clupeidae – herrings L S 

Gizzard shad, Dorosoma 

cepedianum

L R 

Common carp, Cyprinus 

carpio 

W E 

Fathead minnow, Pimephales 

promelas 

W E 

Golden shiner, Notemigonus 

crysoleucus 

L R 

Goldfish, Carassius auratus L S 

Grass Carp, 

Ctenopharyngodon idella 

L E 

Family Cyprinidae – 

minnows 

Red shiner, Cyprinella 

lutrensis 

W E 

Bigmouth buffalo, Ictiobus 

cyprinellus 

L S 

Black buffalo, Ictiobus niger L S 

Family Catostomidae – 

suckers 

Smallmouth buffalo, Ictiobus 

bubalus 

L S 

Black bullhead, Ameiurus 

melas 

W E 

Channel catfish, Italurus 

punctatus 

W E 

Flathead catfish, Pylodictis 

olivaris 

W E 

Family Ictaluridae – catfishes 

Yellow bullhead, Ameiurus 

natalis 

W E 

Family Esocidae – pikes Northern pike, Esox lucius L R 

Arctic grayling, Thymallus 

arcticus16

L S 

Brook trout, Salmo trutta W S 

Brown trout, Salvelinus 

fontinalis 

W S 

Family Salmonidae – trouts 

Rainbow trout, Oncorhynchus 

mykiss1

W S 

Guppy, Poecilia reticulata L S 

Sailfin molly, Poecilia 

latipinna 

L S 

Family Poecilidae - 

livebearers 

Western mosquitofish, 

Gambusia affinis 

W E 

Striped bass, Morone saxatilis L E 

White bass, Morone chrysops L E 

Family Moronidae – 

temperate bass 

Yellow bass, Morone 

mississippiensis 

L S 

 

15 Established = reproducing population on a multigeneration timeframe. 

16 Routinely stocked 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 113
STATUS SPECIES DISTRIBUTION TREND 

Black crappie, Pomoxis 

nigromaculatus 

W S 

Bluegill, Lepomis macrochirus W E 

Green sunfish, Lepomis 

cyanellus 

W E 

Largemouth bass, Micropterus 

salmoides 

W E 

Redear sunfish, Micropterus 

microlophus 

W S 

Smallmouth bass, Micropterus 

dolomieu 

W E 

Family Centrarchidae – 

sunfishes and black bass 

White crappie, Pomoxis 

annularis 

L S 

Family Percidae – perches Walleye, Stizostedion vitreum L S 

Yellow perch, Perca 

flavescens 

L R 

Family Cichlidae - ciclids African cichlids, Tilapia and 

Oreochromis spp. 

L E 

Distribution acronyms are W = widespread, L = localized, R = rare. Trend acronyms are E = expanding distribution, 

S = stable distribution, R = recently introduced, trend uncertain. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 114
APPENDIX C 

Fish Barrier Design 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 115
Figure C-1. Profile view of fish barrier. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 116
Figure C-2. Cross section view of channel and floodplain with fish barrier.

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 117
Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 118

APPENDIX D 

List of Stream Renovation Projects in the Lower Colorado River Basin 
Table D-1. Annotated list of stream renovation projects using antimycin in the lower Colorado River basin, and 

Yaqui drainages in Arizona. 

STATE/ COUNTY 

STREAM DATE OF 

PROJECT 

PURPOSE OF PROJECT (primary species targeted for benefit) 

NO. OF 

TREATMENTS 

DID PROJECT ACHIEVE PURPOSE? 

RE

AZ/Pinal Arnett Creek 1996 remove nonnative fish for conservation of 

native fish (longfin dace, desert sucker, Gila topminnow) 

1 yes Biz

AZ/Apache Bearwallow Creek 1981 

1987 

remove nonnative fish for conservation of native fish (Apache trout) 

2 1981 yes* 

1987 yes 

RinAGrec

AZ/Graham Bylas Springs 

complex 

1982 1984 1996 1997 2000 

remove nonnative fish for native fish conservation (Gila topminnow) 

3 1982 no 

1984 yes* 1996-2000 yes 

MaMeRinSchSch

NM/Catron Dry Creek 1984 

1985 

remove nonnative fish for conservation of native fish (Gila trout) 

2 yes Pro

FW

Yavapai, Gila Fossil Creek 2004 remove nonnative fish for conservation of 

native fish (spikedace, loach minnow) 

2 yes We

AZ/Apache Hay Creek 1989 remove nonnative fish for conservation of 

native fish (Apache trout) 

1 yes* AG

AZ/Apache, Greenlee 

Home Creek 1987 remove nonnative fish for conservation of 

native fish (Apache trout) 

1 yes Rin

AG

NM/Catron Iron Creek 1981 remove nonnative fish for conservation of 

native fish (Gila trout) 

? no Pro

FWCom

AZ/Apache Lee Valley Creek 1982 

1987 2002 

remove nonnative fish for conservation of native fish (Apache trout) 

3 1982 yes* 

1987 yes* 2002 not yet known 

RinAG

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
NM/Catron Little Creek 1982 remove nonnative fish for conservation of 

native fish (Gila trout) 

? ? Pro

FW

NM/Catron, Grant 

Mogollon Creek 1987 

1988 1989 

remove nonnative fish for conservation of native fish (Gila trout) 

3 yes Pro

FW

AZ/Santa Cruz O’Donnell Creek 2002 remove nonnative fish for conservation of 

native fish (Gila chub) 

3 yes H. 

July 

AZ/Apache Ord Creek 1977 

1978 1980 

removal of nonnative fish for conservation of native fish (Apache trout) 

2 no (1977, 

78,80) 

RinMinRin

AZ/Pima Sabino Canyon 1999 remove nonnative fish for conservation of 

native fish (Gila chub) 

2 yes Hay

AZ/Santa Cruz San Rafael Valley 

stock tanks 

2006 remove nonnative fish and bullfrogs for 

conservation of Sonora tiger salamander 

1 not yet known US

AZ/Greenlee Snake Creek 2002 remove nonnative fish for conservation of 

native fish (Apache trout) 

1 not yet known AG

AZ/Apache Stinky Creek 1994 

2002 

remove nonnative fish for conservation of native fish (Apache trout) 

2 1994 yes* 

2002 not yet known 

AGrec

NM/Catron Trail Canyon 1986 

1987 

remove nonnative fish for conservation of native fish (Gila trout) 

2 yes Pro

FW

AZ/Apache West Fork Black 

River, including Burro Creek and Thompson Creek 

1996 remove nonnative fish for native fish 

conservation (Apache trout) 

1 yes AG

rec

AZ/Cochise West Turkey Creek 1999 remove nonnative fish for conservation of 

native fish (Yaqui catfish, longfin dace) 

2 yes Co

NM/Catron White Creek 1991 remove nonnative fish for conservation of 

native fish (Gila trout) 

? yes Ste

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
AZ/Apache Wildcat Creek 1988 remove nonnative fish for conservation of 

native fish (Apache trout) 

1 yes Rin

AGrec

NM/Catron Woodrow Canyon 1987 

1988 

remove nonnative fish for conservation of native fish (Gila trout) 

2 yes Pro

FW

* Treatment was apparently successful, but reinvasion occurred, either from adjacent waters or by illegal introduction by humans. 

Bizios, L. 1997. Final report for the Arnett Creek native fish re-establishment project, phase II. September 1997. U. S

Phoenix, AZ. 

Coleman, S.M., and W.L. Minckley. 1999. Management of Yaqui chub and longfin dace in West Turkey Creek, Arizon

the Desert Fishes Council 31:40-41. 

Coman, C.H. 1981. Gila trout management and recovery activities with emphasis on Iron Creek recovery efforts. U.S. 

City, NM. 

Hayes, W. 1999. Memo submitting input for Region V fourth quarter 1998/99 Arizona Game and Fish Department Th

Endangered species report to the Governor. AGFD, Phoenix, AZ. 3 pp. 

Marsh, P.C., and W.L. Minckley. 1990. Management of endangered Sonoran topminnow at Bylas Springs, Arizona: de

and recommendations. Great Basin Naturalist 50(3):265-272. 

Meffe, G. 1983. Attempted chemical renovation of an Arizona springbrook for management of the endangered Sonoran 

American Journal of Fisheries Management 3:315-321. 

Minckley, W.L., and P. Mihalick. 1981. Effects of chemical treatment for fish eradication on stream-dwelling invertebr

Arizona-Nevada Academy of Science 16:79-82. 

Propst, D.L, J.A. Stefferud, and P.R. Turner. 1992. Conservation and status of Gila trout Oncorhynchus gilae. The Sou

37(2):117-125. 

Rinne, J.N., W.L. Minckley, and J.N. Hanson. 1981. Chemical treatment of Ord Creek, Apache County, Arizona, to re-

trout. Journal of the Arizona-Nevada Academy of Science 16:74-78. 

Draft Environmental Assessment Native Fish Restoration in Redrock Canyon 
ish Restoration in Redrock Canyon 

Rinne, J.N., and P.R. Turner. 1991. Reclamation and alteration as management techniques, and a review of methodolog

renovation. Pp. 219-244 in: W.L. Minckley and J.E. Deacon, eds. Battle against extinction. University of Arizona 

Schleusner, C. 2000a. Renovation and habitat restoration for Gila topminnow, Poeciliopsis o. occidentalis, in the Bylas 

Proceedings of the Desert Fishes Council 32:58. 

Schleusner, C. 2000b. Tusidugihalen, “Hot Spring” (S1) and the endangered Gila topminnow habitat improvement and 

Document No. FWS-AZFRO-SC-00-007, June 28, 2000, U.S. Fish and Wildlife Service, Peridot, AZ. 7 pp. 

Stefferud, J.A., D.L. Propst, and G.L. Burton. 1991. Use of antimycin to remove rainbow trout from White Creek, New 

Proceedings of the Desert Fishes Council 23:55-66. 

U.S. Fish and Wildlife Service. 1993. Gila trout recovery plan (revised). FWS, Albuquerque, NM. U.S. Fish and Wildlife Service. 2006c. Final environmental assessment. Small scale exotic species removal in the San 

Arizona. FWS. Phoenix, AZ. 

Weedman, D.A., and P. Sponholtz. 2005. Fossil Creek native fish restoration project. Final Project Report, November 

Reclamation, Arizona Game and Fish Department, U.S. Fish and Wildlife Service, Phoenix, AZ. 

Draft Environmental Assessment Native F
APPENDIX E 

Use of Piscicides and Neutralization Compounds

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 123
Historic Use of Piscicides to Manage Fisheries

Fisheries managers rely on a variety of tools to manage and assess fish populations. 

Historically, these have included the use of piscicides. Two piscicides, rotenone and 

antimycin A, are currently registered by EPA for general use in the United States under 

the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). By law, the EPA is 

authorized to register a pesticide only if it will not cause unreasonable adverse effects on 

human health or the environment. 

Originally, piscicides were mainly used to control out-of-balance or undesirable fish 

populations so that sport fish could be stocked for recreational purposes. Today, 

antimycin and rotenone are used in fisheries management for a variety of purposes, 

including (Finlayson et al. 2000): 

• Eradication of nonnative fish, 

• Restoration of threatened and endangered fish, 

• Support of recreational fisheries by controlling undesirable fish, 

• Eradication of fish to control disease, 

• Quantification of populations of aquatic organisms, 

• Eradication of competing fish in rearing facilities or ponds prior to restocking. 

Although physical removal methods (e.g., nets, traps, seines, electrofishing, dewatering, 

and combinations of physical control techniques) are available for reducing or controlling 

fish communities, they are generally incapable of eradicating fish (Finlayson et al. 2000). 

Meronek et al. (1996) review of fish control projects found that success rates for physical 

removal methods ranged from 33 percent to 57 percent. In most streams, only piscicide 

applications or complete dewatering can eradicate entire populations of undesirable fish 

(Schnick 1974). 

Rotenone

Rotenone has been used in the United States to manage fish populations since the 1930s 

and is the piscicide of choice for application in ponds and lakes. According to the 

American Fisheries Society (Finlayson et al. 2000), rotenone has been routinely used for 

management of fish populations in 34 states and several Canadian provinces. 

Formulations of rotenone are manufactured (under the brand names Pro-Noxfish®, 

Nusyn-Noxfish®, Prenfish®, and others) and shipped in either a powdered or liquid form. 

In addition to applicability as a piscicide, other formulations of rotenone are registered in 

the United States as an insecticide for domesticated pets (dogs and cats), cattle, sheep, 

ornamental plants, trees, and turf; and foliar preharvest application to vegetables, berries, 

tree fruit, nuts, forage crops, and sugar cane. 

Rotenone is a naturally occurring compound extracted from the roots of certain species of 

the bean family that has been used for centuries to capture fish (Finlayson et al. 2000). 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 124
As a piscicide, rotenone interrupts cellular respiration in gill-breathing animals by 

blocking the transfer of electrons in the mitochondria. Acute exposure to toxic levels 

reduces cellular uptake of blood oxygen, resulting in increased cellular anaerobic 

metabolism and associated production of lactic acid causes blood acidosis (Fajt and 

Grizzle 1998). Death results from tissue anoxia, which typically produces cardiac and 

respiratory failure (Ling 2003). Scientists believe that fish are more sensitive to rotenone 

because it is rapidly absorbed into the bloodstream from water flowing across the gill 

membrane. Although both fish and aquatic macroinvertebrates are highly susceptible to 

rotenone (Skaar 2001), most macroinvertebrate populations quickly recover to pretreatment levels (Lennon 1971, Schnick 1974b). Gill-breathing amphibians (i.e., frog and 

toad tadpoles and larval salamanders) are also adversely affected (Hamilton 1941). 

Amphibian adults and reptiles are less sensitive than fish and should not be harmed when 

rotenone is applied at concentrations typically used in fisheries management (Farringer 

1972). Fall applications of rotenone reduce or eliminate impacts on amphibians because 

most species are in the adult stage of development. 

When applied at recommended doses for fish control (0.005 to 0.250 mg/L), rotenone has 

low toxicity to non-aquatic organisms. Extensive research has demonstrated that 

rotenone does not cause birth defects (Hazelton 1982), reproductive dysfunction (Spencer 

and Sing 1992), gene mutations (Biotech 1981, Goethem et al. 1981, NAS 1983) or 

cancer (EPA 1981, Tisdel 1985). The results of chronic feeding studies in which rats and 

dogs that were fed forms of rotenone as part of their diet for 6 months to 2 years resulted 

in non-lethal effects such as diarrhea, decreased food consumption, and weight loss 

(Skaar 2001). No adverse chronic effect was reported when rats where given 100 mg/L 

Pro-Noxfish® (2.5 percent rotenone) in drinking water for 70 weeks (Brooks and Price 

1961). Ellis et al. (1980) found that 10 mg/kg/day rotenone administered orally to 

beagles for 26 weeks had no adverse chronic effect. Skaar (2001) reported that a 20- 

pound dog would have to consume 660,000 pounds of rotenone-tainted fish to receive a 

lethal dose, and bird mortality would require 1,000 to 10,000 times greater rotenone 

levels than used in piscicide applications (Skaar 2001). A bird weighing a quarter of a 

pound would have to eat more than 40 pounds of fish and invertebrates killed by rotenone 

within 24 hours before receiving a lethal dose (Finlayson et al. 2000). Studies that 

examined avian exposure report that a 1,000 to 10,000-fold increase in levels normally 

used for fisheries management would be required for lethality (Skaar 2001). 

Several hazard assessments for human health have also been conducted. Simulated lethal 

oral dosage for a human is variously estimated between 300 to 500 mg/kg (Ray 1991, 

Gosselin et al. 1984). Gleason et al. (1969) estimated the lowest dose for lethality would 

require a 60-kg person to consume 180,000 liters of water containing 0.1 mg/L rotenone, 

or eat 180 kg of rotenone–killed fish at one sitting. Although ingestion of rotenone-killed 

fish is not recommended, the rotenone level in fish considered safe for human 

consumption has been estimated at 10 ppm (Lehman 1950). Skaar (2001) notes that the 

National Academy of Sciences established in 1983 a “suggested no-adverse response 

level” of rotenone in drinking water of 0.014 mg/L, assuming a 70-kg person drinks 2 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 125
liters of water per day for a lifetime. In 1997, the EPA established a human ingestion risk 

value (reference dose for chronic exposure) of 0.004 mg/kg/day.17 

An Emory University study (Betarbet et al. 2000) reported finding anatomical, 

neurochemical, and behavioral symptoms characteristic of Parkinson’s disease in 

laboratory rats when rotenone was administered chronically and intravenously. However, 

several researchers in Parkinson’s disease (including J. Langston, Director of the 

Parkinson’s Institute) have stated the Emory University does not show evidence that 

exposure to rotenone causes Parkinson’s disease. The continuous jugular vein infusion of 

rotenone lead to continuously high levels of rotenone in the bloodstream and included 

dimethyl sulfoxide to enhance tissue penetration. This mode of administration to 

laboratory rats was unnatural and cannot be used as a model for any environmental 

exposure to rotenone. The normal exposure to rotenone in humans from its use in 

fisheries management would be ingestion, inhalation, or through the skin. Rotenone that 

is ingested by mammals (and birds) is rapidly broken down by enzymatic action in the 

gut and excreted by the liver and kidney. Approximately 20 percent of the oral dose (and 

probably most of the absorbed dose) is excreted within 24 hours (Ray 1991). In the 

Emory University study, Betarbet et al. (2000) concluded that “rotenone seems to have 

little toxicity when administered orally.” 

Rotenone is very unstable in the environment (half-life measured in days) and completely 

breaks down within 1 to 4 weeks depending on pH, alkalinity, temperature, dilution, and 

exposure to sunlight (Schnick 1974b). It also adsorbs strongly to organic matter in 

sediment and is rapidly degraded (Dawson et al. 1991). Rapid neutralization (oxidation) 

occurs when rotenone is mixed with potassium permanganate or sodium permanganate 

(Engstrom-Heg 1971, 1972, 1973; Finlayson et al. 2000). Inert ingredients in the liquid 

formulation of rotenone consist of petroleum hydrocarbons as solvents and emulsifiers 

(primarily naphthaline, methylnaphthalenes, trichloroethylene, and xylenes). Studies of 

residual concentrations in water treated with liquid formulations indicate that solvent 

levels are below toxic thresholds (Ling 2003). In a study of rotenone-treated streams and 

lakes in Californian, concentrations of trichloroethylene never exceeded the Federal 

drinking water standard (Maximum Contaminant Level) of 5 ug/L and similarly the 

concentrations of xylene never exceeded the drinking water standard (Health Advisory) 

of 620 ug/L (Finlayson et al. 2001). Drinking water standards for naphthalenes and 

methynaphthtalenes have not been established. Finlayson et al. (2001) noted that all the 

volatile and semivolatile organic compounds disappeared before rotenone dissipated from 

the treated waters. There are no Federal or Arizona water quality standards for rotenone. 

Rotenone does not easily enter groundwater because of its tendency to bind rapidly with 

organic material in soil and surface water (DOE 2004). In a California groundwater 

study, no trace of rotenone (including any of the compounds in the formulated product) 

was detected in 26 wells that were placed in aquifers adjacent to and downstream of nine 

rotenone-treated water bodies (CDFG 1994). A similar study at Tetrault Lake, Montana, 

failed to detect rotenone in a nearby domestic well that was sampled 2 and 4 weeks after 

 

17 A reference dose is an estimate of a daily exposure to the human population (including sensitive 

subgroups) that is likely to be without an appreciable risk of deleterious effects during a lifetime. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 126
treatment of the lake with 90 ug/L of the piscicide (DOE 2004). The Tetrault Lake well 

site was studied because it was downgradient from the lake and drew water from the 

same aquifer that fed and drained the lake. In another study, water from a well located 65 

feet from a rotenone-treated pond near Kalispell, Montana, was analyzed and showed no 

sign of piscicide contamination (DOE 2004). 

The major risks to human health from rotenone come from exposure during application. 

This is the only time when humans (applicators) are exposed to high concentrations of the 

piscicide. Personal protective equipment is required by the product label and material 

safety data sheet to reduce respiratory and dermal exposure. For liquid and powder 

rotenone formulation application, personnel must wear approved air purifying respirators, 

goggles, rubber gloves, and protective clothing. 

Any threat to recreational users during treatment can be readily mitigated through 

cautionary signing at access points, temporary closures, and posting agency personnel 

within the treatment area. 

Antimycin A 

The only other piscicide registered for general use in the United States is antimycin A 

(Finlayson et al. 2000). Antimycin A was first patented for piscicide use in 1964. It is 

also approved for use in commercial catfish farms by the Food and Drug Administration. 

Formulations of antimycin A are registered under the brand name Fintrol®. 

Like rotenone, antimycin inhibits cellular respiration in gill-breathing animals (Schnick 

1974a). When used in appropriate concentrations for fisheries management, antimycin is 

often less harmful to non-target aquatic organisms than rotenone. Some studies have 

shown effects on aquatic insects vary according to species and stream setting. Cerreto et 

al. (2003) found that antimycin had little to no effect on aquatic macroinvertebrates in 

high elevation (approximately 7,900 feet) streams in Bridger-Teton National Forest in 

Wyoming. Lennon et al. (1971) stated that antimycin is the ideal piscicide because of its 

selective effects and effectiveness at low concentrations in a wide range of water 

qualities, it is not repulsive to fish, and it leaves no toxic residue. 

Antimycin A is an organic compound that was isolated from the bacterium Streptomyces 

girseus at University of Wisconsin in 1945 (Leben and Keitt 1948, Dunshee, et al. 1949). 

The chemical formula of antimycin is C28H40N2O9 (Rinne and Turner 1991:237), and it 

inhibits growth of some fungi but does not affect most bacteria. The formulations often 

used for fish control in streams are Fintrol-Concentrate (liquid form antimycin A) and 

Fintrol 15 (antimycin A coated sand). Antimycin A consists of 10 percent antimycin and 

inert constituent components (soy lipds, Diethyl phthalate, Nonoxyl-9 detergent [or 

nonylphenol polyglycol ether], and acetone). 

Degradation of antimycin is by the following pathway (Hussain 1969): 

antimycin A1 → blastmycic acid + antimycin lactone → fatty acids 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 127
Temperature and pH strongly influence the efficacy and rate of degradation of antimycin 

(Chapman et al. 2003). Antimycin degrades slower in lower temperature water, but it is 

also less effective, probably because at lower temperatures the metabolism and 

respiration rate in fish decrease, thereby affecting the rate of toxicant uptake (Berry and 

Larkin 1954). Marking and Dawson (1972) reported the following half lifes of antimycin 

based on pH: pH 6 to 6.5 = 310 hours, pH 7.5 = 120 hours, and pH 8 = 100 hours. 

Degradation of antimycin occurs quickly under natural stream conditions because of 

dilution, adsorption to organic material and sediments, and oxidation created by sunlight 

and water turbulence (Lee et al. 1971). Other compounds that will readily bind with 

antimycin to detoxify it include leafy vegetation and water plants (Grisak 2003). Rapid 

neutralization occurs when antimycin is mixed with potassium permanganate or sodium 

permanganate (Marking and Bills 1975). The degradation compounds have very low 

toxicity for either fish or mammals (Herr et al. 1967). Drinking water standards have not 

been established for the commercial piscicide formulation of antimycin A. There are no 

Federal or Arizona water quality standards for antimycin A. 

A review of toxicity studies relating to antimycin indicates that vertebrate animals must 

ingest high dosages before any adverse effect is apparent (Schnick 1974a). In laboratory 

tests, oral LD50 values for mammals ranged from 1.0 mg/kg for lambs to 55 mg/kg for 

mice (Herr et al. 1967). Oral LD50 is defined as the amount of antimycin administered 

orally over a specified period of time that causes the death of 50 percent of the group of 

test animals. For example, if a person weighing 70 kg consumed 1.5 liters from a stream 

treated with 200 ug/L antimycin (recommended concentrations typically range from 5 to 

25 ug/L), that person would ingest 300 ug of antimycin, or 0.0042 mg/kg of body weight. 

A 154 pound person would have to drink about 167 gallons of treated water during the 

period that antimycin is active to ingest the amount required to achieve the LD50 for the 

most sensitive mammal tested (Guinea pig, LD50 = 1.8 mg antimycin/kg body weight). 

This translates to a water consumption rate of about 28 gallons per hour during an active 

treatment period lasting 6 hours. Similarly, an 800-pound horse would have to ingest 

about 860 gallons of water with levels similar to piscicide treatment before there could be 

a significant chance of death (Herr et al. 1967). 

Consumption of antimycin in water was alleged to have caused organ abnormalities and 

stillbirth of two lambs in northern New Mexico in 1998 (Begel 2001). However, no 

evidence implicating antimycin in the stillbirth of the two lambs was produced, and no 

adverse effects on animals in the surrounding area were reported (AFSFMCS et al. 2001). 

In addition, an independent medical microbiologist contracted by Grant and Catron 

counties in New Mexico to review the potential public health hazards of antimycin 

concluded that it was an effective and safe fish control agent for removal of fishes from 

streams with no potential for public health issues when applied at recommended 

concentrations (Brooks and Propst 2001). Vezina (1967) reported that antimycin is not 

hazardous to humans, livestock, and wildlife when applied at concentrations appropriate 

for fisheries management. 

The potential effects of consuming dead fish produced by stream renovation are poorly 

studied, but there have never been any reports of negative effects to humans or wildlife 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 128
from ingestion of antimycin-killed fish (Berger et al. 1967, Gilderhus et al. 1969). Ritter 

and Strong (1966) reported that 21 humans who consumed between one and five 4-ounce 

servings of fish killed by antimycin suffered no ill effects. Schnick (1974) reported that 

antimycin is not hazardous to humans whether it is consumed in food or water. In a study 

on waterfowl, Vezina (1967) found that consumption of 2,900 mg antimycin/kg body 

weight was required to cause mortality of 50 percent of test mallard ducks in the 

laboratory. Similar tests on 4.5 kg domestic dogs required consumption of 5,000 mg/kg 

antimycin to cause mortality of 50 percent of the test population. In another laboratory 

study, trout killed with 10 ug/L antimycin contained 76 to 388 ug/kg antimycin in their 

tissues (Ritter and Strong 1966). 

The major risks to human health from antimycin come from exposure during application. 

This is the only time when humans (applicators) are potentially exposed to high 

concentrations of the piscicide. Personal protective equipment is required by the product 

label and material safety data sheet to reduce respiratory and dermal exposure. For liquid 

and powder antimycin formulation application, personnel must wear approved air 

purifying respirators, goggles, rubber gloves, and protective clothing. 

Any threat to recreational users during treatment can be readily mitigated through 

cautionary signing at access points, temporary closures, and posting agency personnel 

within the treatment area. 

Potassium Permanganate and Sodium Permanganate 

Potassium permanganate (KMnO4) is the chemical most often used to quickly neutralize 

(oxidize) rotenone and antimycin, and recently sodium permanganate (NaMnO2) has also 

been used for this purpose. Since permanganate itself may be toxic to aquatic organisms 

at high dosages, detoxification procedures would utilize calibrated equipment to achieve 

minimum effective concentration of permanganate to neutralize the piscicide. 

Monitoring stations consisting of caged live fish would be placed at the downstream limit 

of the treatment area to verify detoxification of the piscicide and permanganate. 

Potassium Permanganate. Potassium permanganate reduces the half-life of antimycin to 

7 to 11 minutes in a laboratory setting. Horton (1997) recommends a 20-minute 

neutralization period for rotenone in non-alpine streams. Potassium permanganate is a 

strong oxidizing agent that quickly breaks down to naturally occurring compounds 

(Archer 2001). Kemp et al. (1966) and Marking and Bills (1975) found that organic 

material and inorganic oxidation substances rapidly decrease the activity of potassium 

permanganate. 

Potassium permanganate can be toxic to fish (Tucker and Boyd 1977, Archer 2001, 

Grisak et al. 2002). In the laboratory, exposure to 2 mg/L KMnO4 was lethal to rainbow 

trout (Archer 2001). When applied at 1.5 mg/L in the absence of readily oxidizable 

substances, potassium permanganate achieved lethality in westslope cutthroat trout after 

16 to 24 hours of exposure (Grisak et al. 2002). Potassium permanganate is quickly 

broken down when it reacts to organic material and antimycin or rotenone in stream 

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Native Fish Restoration in Redrock Canyon 129
water. Breakdown components of potassium permanganate (potassium, manganese, and 

water) are common in nature and have no deleterious environmental effects at 

concentrations used for neutralization of piscicides (Finlayson et al. 2000). 

Potassium permanganate is also one of the most widely used inorganic chemicals for the 

treatment of municipal drinking and wastewater. According to the American Waterworks 

Association’s Water Industry Data Base, potassium permanganate is listed as the second 

most widely used chemical for predisinfection and oxidation by treatment plants 

processing surface waters. Hundreds of drinking water treatment plants use this chemical 

to oxidize iron, manganese, and arsenic; to remove color; and to treat for biofilm in raw 

water intake pipes. 

Potassium permanganate is also used in fish farming to prevent or alleviate oxygen 

shortages in rearing ponds. The chemical works by oxidizing decaying plant matter and 

other organics so that they consume less oxygen, thereby relieving oxygen depletions that 

otherwise could result in fish kills. 

Sodium Permanganate. Sodium permanganate is another strong oxidizing agent that can 

be used to neutralize rotenone and antimycin. Like potassium permanganate, this 

permanganate compound has a low estimated lifetime in the environment and is readily 

degraded by organic material and inorganic oxidation substances (Sino-American 2002). 

In a stream, sodium permanganate will quickly degrade as it neutralizes the piscicide and 

reacts to any organic material. The breakdown components of sodium permanganate are 

sodium, manganese, and water. 

Sodium permanganate is also used for in situ chemical oxidation of chlorinated organic 

contaminants in soil and groundwater. Liquid sodium permanganate is injected into the 

soil or groundwater and allowed to disperse through the contaminated media. In situ 

chemical oxidation using sodium permanganate is an effective and environmentally 

acceptable method of remediating contaminated soil and groundwater. 

Piscicide Use and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 

FIFRA requires that all persons who apply pesticides classified as restricted use (such as 

piscicides) be certified according to the provisions of the Act, or that they work under the 

supervisions of a certified applicator. Commercial and public applicators must 

demonstrate a practical knowledge of the principles and practices of pest control and safe 

use of pesticides. In addition, applicators using or supervising the use of any restricteduse pesticides purposefully applied to standing or running water are required to pass an 

exam (Aquatic Pest Control) to demonstrate competency as described in the Code of 

Federal Regulations (40 CFR 171.4), as follows: 

Aquatic applicators shall demonstrate practical knowledge of the secondary 

effects which can be caused by improper application rates, incorrect 

formulations, and faulty application of restricted pesticides used in the category. 

They shall demonstrate practical knowledge of various water use situations and 

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Native Fish Restoration in Redrock Canyon 130
the potential for downstream effects. Further, they must have practical 

knowledge concerning potential pesticide effects on plants, fish, birds, beneficial 

insects, and other organisms which may be present in aquatic environments. 

Applicants in this category must demonstrate practical knowledge of the 

principles of limited area application. 

Piscicide Use and the Clean Water Act 

Under FIFRA, EPA is charged to consider the effects of pesticides on the environment by 

determining whether a pesticide will perform its intended function without unreasonable 

adverse effects. In an agency guidance letter dated July, 11, 2003, EPA recognized the 

inherent value of pesticide applications to control nonnative species and stated that when 

a pesticide is applied directly to waters of the United States according to its “intended 

purpose” as allowed under FIFRA, it is not a pollutant under the Clean Water Act. The 

EPA further noted that the application of a pesticide in compliance with FIFRA 

requirements does not require an NPDES permit under the Clean Water Act when the 

pesticide is applied to water to control pests. A decision by the United States Court of 

Appeals for the Ninth Circuit (Fairhurst vs. Hagener) reaffirmed EPA’s decision that a 

pesticide applied to a river for the purpose of “eliminating pestilent fish species is not a 

pollutant for the purposes of the Clean Water Act...and thus not subject to the Act’s 

permit requirements.” 

Literature Cited 

AFSFMCS (American Fisheries Society Fish Management Chemicals Subcommittee) 

and eight coauthors. 2001. Fisheries forum opinion: response to Begel (2001). 

Fisheries (Bethesda) 26(8):40. 

Archer, D.L. 2001. Rotenone neutralization methods, pp 5-8. In: R.L. Cailteux, L. 

DeMong, B.J. Finlayson, W. Horton, W. McClay, R.A. Schnick, and C. Tompson, 

(eds). Rotenone in fisheries: are the rewards worth the risks? American Fisheries 

Society, Trends in Fisheries Science Management. Bethesda, MD. 

Begel, D. 2001. Debate rages over fish poisoning. High Country News 33(9):5. 

Berger, B.L., P.A. Gilderhus, and R.E. Lennon. 1967. Attempted reclamation of 

Whitewater Lake, Valentine National Wildlife Refuge, Nebraska. Unpublished 

report, U.S. Fish and Wildlife Service, Fish Control Laboratory, La Crosse, WI. 

Berry, G. and P.A. Larkin. 1954. Field trials with “Fish-Tox” in streams. Canadian Fish 

Culturist 15:10-15. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 131
Biotech Research. 1981. Analytical studies for detection of chromosomal aberrations in 

fruit flies, rats, mice, and horse bean. Report to U.S. Geological Survey. Upper 

Midwest Environmental Sciences Center (FWS Study 14-16-990-80-54). La 

Crosse, WI. 

Brooks, I.C., and R.W. Price. 1961. Studies on the chronic toxicity of Pro-Noxfish, a 

proprietary synergized rotenone fish-toxicant. Toxicol. Appl. Pharmacol. 3:49-

56. 

Brooks, J.E., and D.L. Propst. 2001. Use of antimycin-A in Gila trout recovery: 

response to public concerns. Pages 15-16 in Practical approaches for conserving 

native inland fishes of the west: a symposium. Missoula, MT, June 6-8, 2001. 

Cerreto K.M., R.O. Hall, Jr., and H. Sexauer. 2003. Short-term effects of antimycin and 

rotenone on invertebrates in first-order, high-elevation streams. Paper presented 

at the North American Benthological Society annual meeting, Athens, GA, 2003. 

Chapman, D., J. Fairchild, B. Carollo, J. Deters, K. Feltz, and C. Witte. 2003. An 

examination of the sensitivity of bighead carp and silver carp to antimycin A and 

rotenone. U.S. Geological Survey. Columbia, MO. 

Ellis, H.V., S. Unwin, J. Cox, I.S. Elwood, E.A. Castillo, and J. Carter. 1980. 

Subchronic oral dosing study for safety evaluation of rotenone using dogs. 

Midwest Research Institute Project No. 4853-B. La Crosse, WI. 

Engstrom-Heg, R. 1971. Direct measure of potassium permanganate demand and 

residual potassium permanganate. New York Fish and Game Journal, vol. 18, 

2:117-122. 

Engstrom-Heg, R. 1972. Kinetics of rotenone-potassium permanganate reactions as 

applied to the protection of trout streams. New York Fish and Game Journal, 

vol. 19, 1:47-58. 

Engstrom-Heg, R. 1976. Potassium permanganate demand of a stream bottom. New 

York Fish and Game Journal, vol. 23, 2:155-159. 

Dawson, V.K., W.H. Gingerich, R.A. Davis, and P.A Gilderhus. 1991. Rotenone 

persistence in freshwater ponds: effects of temperature and sediment 

adsorption. North American Journal of Fisheries Management 11:226-231. 

Department of Energy (DOE). 2004. South fork flathead watershed westslope cutthroat 

trout conservation program. Draft environmental impact statement. DOE/EIS0353. Bonneville Power Administration. Portland, OR. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 132
Dunshee, B.R., C. Leben, G.W. Keitt, and F.M. Strong. 1949. The isolation and 

properties of antimycin A. Journal of the American Chemical Society 71:2436-

2437. 

Environmental Protection Agency (EPA). 1981. Completion of pre-RPAR review of 

rotenone. EPA, Office of Toxic Substances. EPA Report 540/RS-89-039. 

Washington, D.C. 

Fajt, J.R., and J.M. Grizzle. 1998. Blood respiratory changes in common carp exposed 

to a lethal concentration of rotenone. Transactions of the American Fisheries 

Society 127:512-516. 

Farringer, J.E. 1972. The determination of the aquatic toxicity of rotenone and Bayer 73 

to selected aquatic organisms. University of Wisconsin. Lacrosse, WI. 

Finlayson, B.J., and seven coauthors. 2000. Rotenone use in fisheries management: 

administrative and technical guidelines manual. American Fisheries Society, 

Bethesda, MD. 

Gilderhus, P.A., B.L. Berger, and R.E. Lennon. 1969. Field trials of antimycin A as a 

fish toxicant. U.S. Bureau of Sport Fisheries and Wildlife, Investigations in Fish 

Control No. 27. Washington, D.C. 

Goethem, D., B. Barnhart, and S. Fotopoulos. 1981. Mutagenicity studies on rotenone. 

Report to the U.S. Geological Society (FWS Study 14-16-009-80-076). La Cross, 

WI. 

Gosselin, R.E., R.P. Smith, and H.C. Hodge. 1984. Clinical toxicology of commercial 

products. Fifth Edition. Williams and Wilkins. Baltimore/London. 

Grisak, G. 2003. South Fork Flathead watershed westslope cutthroat trout conservation 

program. Specialist report for environmental impact statement. Montana Fish, 

Wildlife and Parks. 

Grisak, G., G. Michael. J. Cavigi, and D. Skaar. 2002. Determination of lethal doses of 

rotenone and potassium permanganate to westslope cutthroat trout, and ability of 

potassium permanganate to neutralize rotenone in the presence of fish. Draft 

report. Montana Fish, Wildlife and Parks. 

Haag, H.B. 1931. Toxicological studies of Derris elliptica and its constituents. I. 

Rotenone. Journal of Pharmacology and Experimental Therapeutics 43:193-208. 

Hamilton, H.L. 1941. The biological action on freshwater animals. Proceedings of the 

Iowa Academy of Science 48:467-479. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 133
Hazelton Raltech Laboratories. 1982. Teratology studies with rotenone in rats. Report 

to U.S. Geological Survey. Upper Midwst Environmental Sciences Center (FWS 

Study 81-178). La Crosse, WI. 

Herr, F., E. Greselin, and C. Chappel. 1967. Toxicology studies of antimycin, a fish 

eradicant. Transactions of the American Fisheries Society 96:320-326. 

Horton, W.D. 1997. Federal aide in sport restoration fishery management program, lake 

renovation manual. Idaho Department of Fish and Game. Boise, ID. 

Hussain, A. 1969. Kinetics and mechanism of hydrolysis of antimycin A in solution. 

Journal of Pharmaceutical Sciences 58:316-320. 

Kemp, H.T., R.G. Fuller, and R.S. Davidson. 1966. Potassium permanganate as an 

algaecide. Journal of the American Water Works Association. 58:225-263. 

Leben, C., and G.W. Keitt. 1948. An antibiotic substance active against certain 

phytopathogens. Phyopathology 38:899-906. 

Lee, T.H., P.H. Derse, and S.D. Morton. 1971. Effects of physical and chemical 

conditions on the detoxification of antimycin. Transactions of the American 

Fisheries Society 100:13-17. 

Lehman, A.J. 1950. Some toxicological reasons why certain chemicals may or may not 

be permitted as food additives. Quarterly Bulletin of the Association of Food and 

Drug Officials of the United States 14:82. 

Lennon R.E. 1970. Control of freshwater fish with chemicals. Proceedings of the 

Vertebrate Pest Conference, Sacramento, CA 4:129-137. 

Ling, N. 2003. Rotenone – a review of its toxicity and use for fisheries management. 

Science for Conservation. Department of Conservation. Wellington, New 

Zealand. 

Marking, L.L., and V.K. Dawson. 1972. The half-life of biological activity of antimycin 

determined by fish bioassay. Transactions of the American Fisheries Society 

101:100-105. 

Marking, L.L., and T.D. Bills. 1975. Toxicity of potassium permanganate to fish and its 

effectiveness in detoxifying antimycin. Transactions of the American Fisheries 

Society, 3:579-583. 

Meronek, T.G. and eight other authors. 1996. A review of fish control projects. North 

American Journal of Fisheries Management 16:63-74. 

Draft Environmental Assessment 

Native Fish Restoration in Redrock Canyon 134
National Academy of Sciences (NAS). 1983. Drinking water and health, Volume 5. 

Safe Drinking Water Committee Board of Toxicology and Environmental Health 

Hazards. Commission on Life Sciences. National Research Council. National 

Academy Press. Washington, D.C. 

Potter, V.R., and A.E. Reiff. 1952. Inhibition of an electron transfer component by 

Antimycin A. The Journal of Biological Chemistry 194:287-297. 

Ray, D.E. 1991. Pesticides derived from plants and other organisms. Handbook of 

Pesticide Toxicology. Academic Press. NY. 

Rinne, J.N., and P.R. Turner. 1991. Reclamation and alteration as management 

techniques, and a review of methodology in stream renovation. Pages 219-244 in 

W.L. Minckley and J.E. Deacon, editors. Battle against extinction: native fish 

management in the American West. The University of Arizona Press, Tucson, 

AZ. 

Ritter, P.O., and F.M. Strong. 1966. Residues in tissues of fish killed by antimycin. 

Journal of Agriculture and Food Chemistry 14:403-407. 

Schnick, R. A. 1974a. A review of the literature on the use of antimycin in fisheries. 

U.S. Fish and Wildlife, Bureau of Sport Fisheries, Fish Control Laboratory, La 

Crosse, WI. 

Schnick, R. A. 1974b. A review of the literature on the use of rotenone in fisheries. 

USDI Fish and Wildlife. La Crosse, WI. 

Sino-American Pigment Systems, Inc. 2002. Material safety data sheet for sodium 

permanganate. 

Skaar, D. 2001. Summary of persistence and toxic effects of rotenone. Status report. 

Montana Fish, Wildlife and Parks. Helena, MT. 

Tiffan, K.E., and E.P. Bergersen. 1996. Performance of antimycin in high-gradient 

streams. North American Journal of Fisheries Management, 16:465-468. 

Tisdale, M. 1985. Chronic toxicicty study of rotenone in rats. Report to the U.S. 

Geological Survey. Upper Midwest Environmental Sciences Center (FWS Study 

No. 6005-100). La Crosse, WI. 

Tucker, C.S., and C.E. Boyd 1997. Relationships between potassium permanganate 

treatment and water quality. Trans. Amer. Fish. Soc. 106:481-488. 

Vezina, C. 1967. Antimycin A, a teleocidal antibiotic. Ant. Agents Chemo. 1966: 757-

766. 

 

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