U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2016–1112

Relative Distribution and Abundance of Fishes and Crayfish 

in 2010 and 2014 Prior to Saltcedar (Tamarix ssp.) Removal in 

the Amargosa River Canyon, Southeastern California

U.S. Department of the Interior

U.S. Geological Survey

Relative Distribution and Abundance of Fishes and 

Crayfish in 2010 and 2014 Prior to Saltcedar (Tamarix ssp.) 

Removal in the Amargosa River Canyon, Southeastern 

California

By Mark E. Hereford

Open-File Report 2016–1112
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Director

U.S. Geological Survey, Reston, Virginia: 2016

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Suggested citation:

Hereford, M.E., 2016, Relative distribution and abundance of fishes and crayfish in 2010 and 2014 prior to 

saltcedar (Tamarix ssp.) removal in the Amargosa River Canyon, southeastern California: U.S. Geological Survey 

Open-File Report 2016–1112, 18 p., http://dx.doi.org/10.3133/ofr20161112. 

ISSN 2331-1258 (online)
iii

Contents

Abstract ...................................................................................................................................................................... 1

Introduction................................................................................................................................................................. 2

Methods...................................................................................................................................................................... 5

Results and Discussion .............................................................................................................................................. 5

Management Implications......................................................................................................................................... 14

Acknowledgments..................................................................................................................................................... 14

References Cited...................................................................................................................................................... 14

Appendix A. Dominant Vegetation Type, Vegetation Percentage of Cover (2014 only), and Stream Characteristics 

(2014 only) from the 2010 and 2014 Fish and Crayfish Surveys of the Treatment Reach in the Amargosa River, 

California. ................................................................................................................................................................. 16

Figures

Figure 1. Map depicting the location of the surveyed treatment reach located on the Amargosa River within the 

Bureau of Land Management Area of Critical Environmental Concern (ACEC) in California..................................... 4

Figure 2. Length histograms of Amargosa River pupfish (Cyprinodon nevadensis amargosae) captured in the 

treatment reach of the Amargosa River, California during the 2010 and 2014 surveys ............................................. 7

Figure 3. Length histograms of speckled dace (Rhinichthys osculus spp.) captured in the treatment reach of the 

Amargosa River, California during the 2010 and 2014 surveys ................................................................................. 7

Figure 4. Relative distribution and abundance of Amargosa River pupfish (Cyprinodon nevadensis amargosae) 

along the treatment reach of the Amargosa River, California surveyed in 2010 and 2014 ........................................ 9

Figure 5. Relative distribution and abundance of speckled dace (Rhinichthys osculus spp.) along the treatment 

reach of the Amargosa River, California surveyed in 2010 and 2014 ...................................................................... 10

Figure 6. Relative distribution and abundance of western mosquitofish (Gambusia affins) along the treatment 

reach of the Amargosa River, California surveyed in 2010 and 2014 ...................................................................... 11

Figure 7. Relative distribution and abundance of red swamp crayfish (Procambarus clarkii) along the treatment 

reach of the Amargosa River, California surveyed in 2010 and 2014 ...................................................................... 12

Figure 8. Dominant riparian vegetation present at sample sites during the 2010 and 2014 fish and crayfish 

surveys along the treatment reach of the Amargosa River, California. Each dot represents an individual trap 

location .................................................................................................................................................................... 13

Table

Table 1. Total captures and catch per unit effort (CPUE) of fishes and crayfish in the treatment reach of the 

Amargosa River Canyon, California surveyed in 2010 and 2014............................................................................... 6
iv

Conversions Factors

Inch/Pound to International System of Units

Multiply By To obtain

Area

acre 0.40470 hectare (ha)

Flow rate

cubic foot per second (ft3/s) 0.02832 cubic meter per second (m

3

/s)

Length

millimeter (mm) 0.03937 inch (in.)

meter (m) 3.28 foot

kilometer (km) 0.621 mile

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as °F = (1.8 × °C) + 32.

Datum

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).
1 

Relative Distribution and Abundance of Fishes and 

Crayfish in 2010 and 2014 Prior to Removal of Saltcedar 

(Tamarix ssp.) in the Amargosa River Canyon, 

Southeastern California 

By Mark E. Hereford

Abstract

The Amargosa River Canyon, located in the Mojave Desert of southeastern California, contains 

the longest perennial reach of the Amargosa River. Because of its diverse flora and fauna, it has been 

designated as an Area of Critical Environmental Concern and a Wild and Scenic River by the Bureau of 

Land Management. A survey of fishes conducted in summer 2010 indicated that endemic Amargosa 

River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were 

abundant and occurred throughout the Amargosa River Canyon. The 2010 survey reported non-native 

red swamp crayfish (Procambarus clarkii) and western mosquitofish (Gambusia affinis) captures were 

significantly higher, whereas pupfish captures were lower, in areas dominated by non-native saltcedar 

(Tamarix ssp.). Based on the 2010 survey, it was hypothesized that the invasion of saltcedar could result 

in a decrease in native species. In an effort to maintain and enhance native fish populations, the Bureau 

of Land Management removed saltcedar from a 1,550 meter reach of stream on the Amargosa River in 

autumn 2014 and autumn 2015. Prior to the removal of saltcedar, a survey of fishes and crayfish using 

baited minnow traps was conducted in the treatment reach to serve as a baseline for future comparisons 

with post-saltcedar removal surveys. During the 2014 survey, 1,073 pupfish and 960 speckled dace were 

captured within the treatment reach. Catch per unit effort of pupfish and speckled dace in the treatment 

reach was less in 2014 than in 2010, although differences could be owing to seasonal variation in 

capture probability. Non-native mosquitofish catch per unit effort decreased from 2010 to 2014; 

however, the catch per unit effort of crayfish increased from 2010 to 2014. Future monitoring efforts of 

this reach should be conducted at the same time period to account for potential seasonal fluctuations of 

abundance and distribution of fishes and crayfish. A more robust study design that accounts for 

variation in capture probability could be implemented to quantify the effects of habitat modifications on 

abundance of fishes and crayfish. 
2 

Introduction

Almost one-half of the described vertebrate species on Earth are fishes, 700 of which are found 

in the freshwater ecosystems of North America (Allan and Flecker, 1993). Geologic and biologic 

processes have influenced this diversity. Geologic processes can isolate hydrologic drainages, isolating 

fish populations from each other, resulting in genetic dissimilarity between populations and different 

evolutionary trajectories. This has resulted in an extraordinary amount of diversity of different species 

and subspecies of fishes (Allan and Flecker, 1993). However, freshwater fishes and their ecosystems are 

among the most threatened fishes and ecosystems in the World (Ward, 1998; Malmqvist and Rundle, 

2002; Dudgeon and others, 2006). There are many causes for the decrease in biodiversity of freshwater 

fishes, including habitat loss and degradation, invasive species, overexploitation, secondary extinctions, 

chemical and organic pollution, and climate change (Allan and Flecker, 1993). 

One of the major threats to endemic biodiversity of aquatic ecosystems is the invasion of nonnative species (Dudgeon and others, 2006). Non-native saltcedar (Tamarix spp.) has proliferated 

throughout aquatic habitats in the Southwestern United States since its cultivation in the early 1900s (Di 

Tomaso, 1998). Saltcedar can change the dynamics of aquatic ecosystems by lowering the groundwater 

table, altering organic matter inputs, decreasing the amount of sunlight available, and reducing algae 

abundance for aquatic herbivores (Kennedy and Hobbie, 2004; Kennedy and others, 2005). Invasions of 

non-native western mosquitofish (Gambusia affinis), and red swamp crayfish (Procambarus clarkii) also 

pose a major threat to the biodiversity of these unique ecosystems through competition and predation on 

native fishes (Guan and Wiles, 1997; Caiola and de Sostoa, 2005). Removal of saltcedar from aquatic 

ecosystems is a popular management strategy that has a positive effect on the abundance of native fishes 

while also decreasing non-native crayfish, and is a high priority in managing aquatic ecosystems 

throughout the arid Southwest (Kennedy and others, 2005; Shafroth and others, 2005). 

The Amargosa River is an ephemeral stream in the Mojave Desert of southeastern California. 

During the late Pleistocene epoch, it traveled its entire course from southeastern Nevada to what is now 

known as the Badwaters of Death Valley, California (Hubbs and Miller, 1948). Perennial aquatic habitat 

is located where springs and seeps separate long stretches of arid desert. This unique combination of 

arid desert dotted with areas of surface water containing perennial riparian vegetation has allowed for a 

diverse set of aquatic biota, most of which are endemic. Endemic aquatic biota of the Amargosa River 

watershed include the Devils Hole pupfish, eight other subspecies of pupfish, speckled dace, spring 

snails, aquatic beetles, and the very rare Amargosa toad (Anaxyrus nelsoni; Williams and others, 1984; 

Deacon and Deacon-Williams, 1991). Within the Amargosa River watershed, the Amargosa River 

pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) are two 

fishes endemic to the Amargosa River Canyon. 
3 

The Amargosa River Canyon contains the longest perennial reach of the Amargosa River and is 

located in Inyo and San Bernardino Counties, California. Because of the biological importance, 

historical and cultural values, and scenic beauty of the Amargosa River, the Bureau of Land 

Management (hereinafter, BLM) designated 21,552 acres surrounding the river as an Area of Critical 

Environmental Concern (Bureau of Land Management, 2006). Segments of the Amargosa River were 

designated by Congress as Wild and Scenic under provisions of the Omnibus Public Lands Management 

Act of 2009 (Public Law 111-11). In summer 2010, a survey was conducted to determine the relative 

distribution and abundance of Amargosa River pupfish (hereinafter, pupfish) and speckled dace 

throughout the entire 16.75-km perennial reach of the Amargosa River Canyon (Scoppettone and others, 

2011). During the 2010 survey, it was noted that saltcedar had invaded a large part of the Amargosa 

River Canyon. In 2010, pupfish (n=8,558) and speckled dace (n=3,429) were distributed throughout the 

stream in relatively large numbers. However, pupfish captures were substantially less in stream reaches 

dominated by saltcedar. Red swamp crayfish (n=195) and mosquitofish (n=1,095) were relatively rare 

but widespread in distribution, and likely pose a threat to native fishes (Scoppettone and others, 2011). 

In October 2014, a second survey of fishes and crayfish was conducted in the Amargosa River 

Canyon prior to saltcedar removal. Saltcedar was removed in autumn 2014 and autumn 2015 along a 

stream reach (hereinafter, treatment reach) 1.5 river kilometers south of the Old Spanish Trail Highway 

and 1,550 m in length (fig. 1). To facilitate comparison of relative distribution and abundance of fishes 

and crayfish and provide a pre-treatment baseline for saltcedar removal, sampling locations for the fish 

and crayfish survey in 2014 were identical to locations in 2010 in the treatment reach, with the 

exception of a 500-m reach where traps were set at a greater density. 

The objectives of this study are to (1) compare the relative abundance and distribution of 

pupfish, speckled dace, mosquitofish, and crayfish in 2010 and 2014 in the treatment reach, and (2) 

describe the relative abundance and distribution of these species and the surrounding riparian vegetation 

prior to the removal of saltcedar. 
4 

Figure 1. Map showing location of surveyed treatment reach on Amargosa River in Bureau of Land Management 

Area of Critical Environmental Concern (ACEC), southeastern California.
5 

Methods

Sampling for fishes in the treatment reach in 2010 occurred between June 21 and July 29, and 

sampling in 2014 occurred between October 6 and 8. The treatment reach begins 1.5 river kilometers 

downstream of the Old Spanish Trail Highway (OSTH) near the town of Tecopa, California, and ends 

3.05 river kilometers downstream of OSTH. The total stream reach was 1.55 river kilometers in length 

(fig. 1). We used Geographic Information System (GIS) tools in ArcGISTM 10 (Environmental Systems 

Research Institute, 2010) and the National Agricultural Imagery Program (NAIP) to trace stream 

channels and to determine sampling locations. In 2010, there were 32 sample locations 50 m apart in the 

treatment reach. In 2014, the treatment reach was resampled at the same locations as in 2010; however, 

a 500-m section in the middle of the reach (beginning 2.05 river kilometers downstream of the OSTH) 

was sampled every 12.5 m. A total of 62 locations were sampled in 2014. Because of the different 

sample regimes conducted in 2014, the sampled reach was divided into three sections: (1) upper (total 

distance 550 m, 50 m apart, 11 locations in 2010 and 2014), (2) middle (total distance 500 m, 12.5 m 

apart in 2014, 11 locations in 2010 and 41 locations in 2014), and (3) lower (total distance 500 m, 50 m 

apart, 10 locations in 2010 and 2014). Standard Gee minnow traps with 3.3-mm mesh were baited with 

dry dog food and fished overnight (18–22 h) at each sampling location one time during each survey. 

Fish captured were identified to species and enumerated. Ten fish of each species (if available) per trap 

were measured to fork length (speckled dace) or total length (pupfish and mosquitofish). Red swamp 

crayfish also were enumerated and measured from the tip of the rostrum to the tip of the uropods. Fish 

and crayfish captured in traps were placed in a container with regional water until enumerated and 

measured and then returned to the stream in the location where they were captured. Stream depth, width, 

and temperature were recorded at each sample location in 2014. Dominant riparian vegetation type 

(native sedge/non-native Typha spp. or Phragmites australis) based on visual interpretation was 

recorded at each sample location. The 2014 survey of riparian vegetation type was more detailed in that 

it consisted of more categories and percentage of cover for two dominant riparian vegetation types. 

Results and Discussion

Total number of pupfish captured in the treatment reach were similar in 2010 (1,207) and 2014 

(1,073); however, the catch per unit effort (CPUE, catch per trap), was much higher in 2010 (37.72) 

than in 2014 (17.31). Total number of speckled dace captured in the treatment reach were lower in 2010 

(572) than in 2014 (960); however, the CPUE was higher in 2010 (17.88) than in 2014 (15.48). 

Mosquitofish captures were similar in 2010 (137) and 2014 (121) and CPUE was higher in 2010 (4.28) 

than in 2014 (1.95). Crayfish captures were lower in 2010 (73) than in 2014 (226), and CPUE was lower 

in 2010 (2.28) than in 2014 (3.65) (table 1). 

During the 2010 survey, a total of 201 (female=103, male=98) pupfish were measured (total 

length), with a mean length of 45.6 mm (standard deviation [SD]=5.8). During the 2014 survey, a total 

of 270 (female=175, male=85, juvenile=10) pupfish were measured, with a mean length of 41.5 mm 

(SD=7.4). Mean lengths of males (47.4 mm in 2010 and 46.6 mm in 2014) were larger than mean 

lengths of females (43.5 mm in 2010 and 40.3 mm in 2014). Length histograms of pupfish were similar 

in 2010 and 2014, with the exception that in 2014, 10 juveniles were measured ranging from 18 to 26 

mm in length, most likely contributing to the differences in mean lengths between 2010 and 2014 (fig. 

2). More juvenile pupfish were captured in the 2014 survey (taken in autumn) than in the 2010 survey 

(taken in summer), indicating that juveniles in this system do not reach trapping size until autumn. 
6 

During the 2010 survey, a total of 215 speckled dace were measured (fork length), with a mean length 

of 53.4 mm (SD=13.7). During the 2014 survey, a total of 395 speckled dace were measured, with a 

mean length of 47.7 mm (SD=11.6). The length histograms of speckled dace differ between years; in 

2014, there is a clear distinction between two groups of speckled dace (fig. 3). This distinction in 

lengths could be owing to different cohorts present in the population and (or) differences in lengths 

between males and females, which cannot be determined in the field. Mean length of crayfish was 62.4 

mm (SD=8.8, n=73) in 2010 and 61.6 mm (SD = 14.0, n = 143) in 2014. Mean length (total length) of 

mosquitofish was 34.0 mm (SD=8.9, n =67) in 2010 and 30.7 (SD=6.2, n=88) in 2014. 

Table 1. Total captures and catch per unit effort (CPUE) of fishes and 

crayfish in the treatment reach of the Amargosa River Canyon, California, 

surveyed in 2010 and 2014.

Reach Species Capture CPUE

2010 2014 2010 2014

Upper

Pupfish 68 11 6.18 1.00

Speckled dace 344 383 31.27 34.82

Mosquitofish 105 33 9.55 3.00

Crayfish 35 104 3.18 9.45

Middle

Pupfish 652 957 59.27 23.34

Speckled dace 169 457 15.36 11.15

Mosquitofish 24 79 2.18 1.93

Crayfish 24 119 2.18 2.90

Lower

Pupfish 487 105 48.70 10.50

Speckled dace 59 120 5.90 12.00

Mosquitofish 8 9 0.80 0.90

Crayfish 14 3 1.40 0.30

TOTAL

Pupfish 1,207 1,073 37.72 17.31

Speckled dace 572 960 17.88 15.48

Mosquitofish 137 121 4.28 1.95

Crayfish 73 226 2.28 3.65
7 

Figure 2. Length histograms (in millimeters [mm]) of Amargosa River pupfish (Cyprinodon nevadensis amargosae) 

captured in the treatment reach of the Amargosa River, California, during the 2010 and 2014 surveys. Sample size 

of pupfish measured (total length) was 201 (female=103, male=98) in 2010, and 270 (female=175, male=85, 

juvenile=10) in 2014. 

Figure 3. Length histograms (in millimeters [mm]) of speckled dace (Rhinichthys osculus spp.) captured in the 

treatment reach of the Amargosa River, California, during the 2010 and 2014 surveys. Sample size of speckled 

dace measured (fork length) was 215 in 2010 and 395 in 2014. 
8 

The distribution of pupfish in 2010 and 2014 was similar in that most of the large captures 

occurred in the middle reach. In 2010 and 2014, the fewest captures occurred in the upper reach. 

However, pupfish captures (total and CPUE) were lower throughout the entire surveyed area in 2014 

than in 2010, most notably in the upper and lower reaches (fig. 4). Speckled dace captures were higher 

in 2014 than in 2010 in the upper and lower reaches, but lower in the middle reach (fig. 5). Mosquitofish 

distribution was similar in both years, with the exception of the upper reach where captures were lower 

in 2014 (fig. 6). Crayfish captures increased in 2014 in the upper and middle reaches, most notably in 

the upper reach, and decreased in 2014 in the lower reach (fig. 7). Total captures and CPUE for each 

reach and year are shown in table 1. 

In 2010, the riparian vegetation in the upper reach was dominated by cattail (Typha spp.) and 

common reed (Phragmites australis), whereas the middle and lower reaches were dominated by native 

sedges (fig. 8). The 2014 survey consisted of a more detailed survey with more riparian plant 

community descriptions; therefore, a complete comparison across years could not be conducted. 

However, the 2014 survey of riparian vegetation indicated that the middle reach was dominated by 

cattail, whereas the lower reach consisted mostly of sites dominated by sedge. Based on the 2014 

survey, it appears that common reed is spreading throughout the entire study reach (fig. 8). A 

description of the percentage of riparian vegetation cover, stream width, stream depth, and temperature 

for each site is available in appendix A. 

The decrease in pupfish captures in 2014 could be owing to a number of factors other than a 

change in abundance. The timing of sampling was different in 2010 and 2014 so observed differences 

in fish populations could be owing to seasonal changes in recruitment and (or) movement. Streamflows 

in the Amargosa River Canyon are consistent (average 2.21 ft3/s; U.S. Geological Survey, 1995) 

because they originate from springs associated with an alluvial aquifer in contact with bedrock. This 

system, however, is subject to flash flood events. The maximum instantaneous discharge was measured 

at 1,500 ft3/s in February 1969 (Anderson, 2005). A similar event occurred in December 2010 when 

stream discharge peaked at 1,050 ft3/s on the Amargosa River downstream of the OSTH at U.S. 

Geological Survey streamgage 10251300 (U.S. Geological Survey, 2016). This flash flood occurred 

between the two surveys and could have affected the assemblage and abundance of fishes in the 

Amargosa River Canyon, resulting in the lower captures in the 2014 survey (Labbe and Fausch, 2000; 

Dexter and others, 2014; Bond and others, 2015). Changes in riparian vegetation could also contribute 

to changes in fish populations. The vegetation survey conducted in 2014 indicated that the middle reach 

was dominated by cattail and common reed, which have the potential to decrease streamflows creating 

habitat less suitable for species such as pupfish and speckled dace (Scoppettone and others, 2005). 
9 

Figure 4. Relative distribution and abundance of Amargosa River pupfish (Cyprinodon nevadensis amargosae) 

along the treatment reach of the Amargosa River, California, surveyed in 2010 and 2014. Each dot represents an 

individual trap location. Base imagery from National Agriculture Imagery Program (NAIP), 2014.
10 

Figure 5. Relative distribution and abundance of speckled dace (Rhinichthys osculus spp.) along the treatment 

reach of the Amargosa River, California, surveyed in 2010 and 2014. Each dot represents an individual trap 

location. Base imagery from National Agriculture Imagery Program (NAIP), 2014.
11 

Figure 6. Relative distribution and abundance of western mosquitofish (Gambusia affinis) along the treatment 

reach of the Amargosa River, California, surveyed in 2010 and 2014. Each dot represents an individual trap 

location. Base imagery from National Agriculture Imagery Program (NAIP), 2014.
12 

Figure 7. Relative distribution and abundance of red swamp crayfish (Procambarus clarkii) along the treatment 

reach of the Amargosa River, California, surveyed in 2010 and 2014. Each dot represents an individual trap 

location. Base imagery from National Agriculture Imagery Program (NAIP), 2014. 
13 

Figure 8. Dominant riparian vegetation present at sample sites during fish and crayfish surveys along the 

treatment reach of the Amargosa River, California, 2010 and 2014. Each dot represents an individual trap location.

Base imagery from National Agriculture Imagery Program (NAIP), 2014.
14 

Management Implications

The decrease in pupfish CPUE from 2010 to 2014 in this surveyed reach is concerning, although 

this could be an artifact of seasonal variation or a natural response after a flash flood. A survey of this 

reach in the summer months could determine whether this decrease is seasonal or an actual decrease in 

pupfish abundance. Future monitoring efforts of fishes in the Amargosa River Canyon should be 

conducted in the same month to account for seasonal changes in abundance and distribution. A 

quantitative study design that does not rely on the assumption that capture probability remains constant 

over time and space could be more useful as more reaches of stream are treated for removal of saltcedar. 

Although the population of non-native mosquitofish does not appear to be increasing in this reach, the 

red swamp crayfish CPUE has increased. Although saltcedar is an invasive species of concern in the 

Amargosa River Canyon, restoration efforts should consider monitoring and removal of other aquatic 

invasive species such as cattail and common reed as a priority, as these species are becoming more 

prevalent and could negatively affect native fish species by decreasing stream velocities to favor nonnative species. Past fish surveys of the Amargosa River Canyon have indicated that red swamp crayfish 

occur in higher densities in areas dominated by saltcedar (Scoppettone and others, 2011). Kennedy and 

others (2005) showed that removal of saltcedar in a desert stream similar to the Amargosa River 

increased native fish abundance and decreased the abundance of crayfish. The 2010 and 2014 fish and 

crayfish surveys can be used as a baseline to determine the effects of saltcedar removal as a 

management strategy in the Amargosa River Canyon Area of Critical Environmental Concern to 

maintain and enhance the Amargosa River pupfish and speckled dace populations. 

Acknowledgments

Data for this study were collected in 2014 by U.S. Geological Survey Western Fisheries 

Research Center, Reno, Nevada, field station staff Mark Fabes, Pete Rissler, with help from Eric 

Miskow of the Nevada Natural Heritage Program. Gary Scoppettone, Danielle Hereford, Antonio 

Salgado, Mark Fabes, and Pete Rissler of the U.S. Geological Survey Western Fisheries Research 

Center, Reno, Nevada Field station collected data in 2010. 

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U.S. Geological Survey, 2016, National Water Information System—Web interface (USGS water data 

for the Nation), accessed January 27, 2016, at 

http://waterdata.usgs.gov/ca/nwis/uv?site_no=10251300. 
16 

Appendix A. Dominant Vegetation Type, Vegetation Percentage of Cover (2014 only), and Stream 

Characteristics (2014 only) from the 2010 and 2014 Fish and Crayfish Surveys of the Treatment 

Reach in the Amargosa River, California.

[Temp: temperature. Veg 1: first dominant vegetation. Veg 2: second dominant vegetation. Abbreviations: m, meter; mm, millimeter; na, not collected;

°C, degrees Celsius; -, zero observed] 

Dominant vegetation type 2014 vegetation percentage of cover

2014 stream 

characteristics

Reach Station Latitude Longitude 2010 2014 Veg 1 Density 1 Veg 2 Density 2

Depth 

(mm)

Width 

(m)

Temp 

(°C)

Upper AR01500 35.838806 -116.223352 Typha/Phragmites Typha Typha 100 - - 165 10 21.1

Upper AR01550 35.838139 -116.223207 Typha/Phragmites Typha/Phragmites Typha 50 Phragmites 50 300 10 21.7

Upper AR01600 35.837524 -116.223169 Typha/Phragmites Typha/Phragmites Typha 50 Phragmites 50 290 5 21.1

Upper AR01650 35.837126 -116.223373 Typha/Phragmites Typha/Phragmites Typha 50 Phragmites 50 330 5 21.1

Upper AR01700 35.836786 -116.223597 Typha/Phragmites Sedge Sedge 100 - - 220 5 21.1

Upper AR01750 35.836433 -116.22362 Typha/Phragmites Sedge Sedge 100 - - 195 5 21.1

Upper AR01800 35.83587 -116.223552 Typha/Phragmites Phragmites Phragmites 100 - - 325 3 20.6

Upper AR01850 35.835616 -116.224032 Typha/Phragmites Typha Typha 90 - - 570 5 20.0

Upper AR01900 35.835393 -116.22437 Typha/Phragmites Phragmites Phragmites 100 - - 315 3 20.6

Upper AR01950 35.83485 -116.224598 Typha/Phragmites Typha Typha 100 - - 330 10 21.1

Upper AR02000 35.834571 -116.224219 Typha/Phragmites Typha Typha 50 - - 295 2.2 20.6

Middle AR02050 35.834401 -116.223924 Typha/Phragmites Sedge Sedge 5 - - 330 2.5 20.0

Middle AR02063 35.834363 -116.223732 na Typha Typha 25 - - 175 3.4 20.0

Middle AR02075 35.834259 -116.223611 na Typha Typha 50 - - 470 2.6 20.0

Middle AR02088 35.834161 -116.223584 na Typha Typha 50 - - 245 4.1 20.0

Middle AR02100 35.834069 -116.223522 Typha/Phragmites Typha Typha 5 - - 430 4.7 20.6

Middle AR02113 35.833968 -116.223482 na Typha Typha 5 - - 185 2.2 20.6

Middle AR02125 35.833887 -116.223375 na Typha Typha 10 - - 160 2.2 20.6

Middle AR02138 35.833782 -116.223226 na Typha Typha 5 - - 205 2 20.6

Middle AR02150 35.833667 -116.223131 Sedge Sedge Sedge 5 - - 245 2.1 20.6

Middle AR02163 35.833645 -116.222998 na Sedge Sedge 15 - - 375 2.2 21.1
17 

Dominant vegetation type 2014 vegetation percentage of cover

2014 stream 

characteristics

Reach Station Latitude Longitude 2010 2014 Veg 1 Density 1 Veg 2 Density 2

Depth 

(mm)

Width 

(m)

Temp 

(°C)

Middle AR02175 35.833538 -116.223035 na Open Open 0 - - 280 3.1 21.1

Middle AR02188 35.83343 -116.223091 na Phragmites Phragmites 2 - - 175 3.3 21.1

Middle AR02200 35.833354 -116.223155 Sedge Sedge Sedge 75 - - 300 2.6 20.6

Middle AR02213 35.833251 -116.223205 na Sedge Sedge 50 - - 390 3.9 20.6

Middle AR02225 35.833147 -116.223251 na Phragmites/Sedge Phragmites 10 Sedge 10 235 2.4 21.7

Middle AR02238 35.833026 -116.223254 na Typha Typha 5 - - 250 4.8 21.1

Middle AR02250 35.832929 -116.223165 Sedge Typha Typha 15 - - 250 5.2 21.1

Middle AR02263 35.832832 -116.223253 na Typha Typha 2 - - 170 3.9 21.1

Middle AR02275 35.832715 -116.223256 na Open Open 0 - - 160 3.8 21.1

Middle AR02288 35.832616 -116.223248 na Open Open 0 - - 145 3.4 21.7

Middle AR02300 35.832489 -116.223206 Sedge Open Open 0 - - 140 5.7 21.7

Middle AR02313 35.832521 -116.223267 na Open Open 0 - - 150 2.2 21.7

Middle AR02325 35.832393 -116.223312 na Phragmites Phragmites 20 - - 40 2.4 21.7

Middle AR02338 35.83226 -116.223289 na Phragmites/Sedge Phragmites 25 Sedge 25 145 3.1 21.7

Middle AR02350 35.832077 -116.223264 Sedge Phragmites/Sedge Phragmites 10 Sedge 10 195 4.2 21.1

Middle AR02363 35.831973 -116.223246 na Phragmites/Sedge Phragmites 75 Sedge 75 310 3.6 21.7

Middle AR02375 35.831852 -116.223236 na Phragmites Phragmites 10 - - 250 2 21.7

Middle AR02388 35.831749 -116.22317 na Phragmites/Sedge Phragmites 15 Sedge 15 155 3.9 22.2

Middle AR02400 35.831633 -116.223114 Sedge Typha Typha 5 - - 140 3.7 22.2

Middle AR02413 35.831507 -116.223234 na Phragmites Phragmites 10 - - 145 1.9 21.7

Middle AR02425 35.831406 -116.223258 na Phragmites Phragmites 15 - - 210 2.9 21.7

Middle AR02438 35.831294 -116.223233 na Sedge Sedge 90 - - 200 3.6 21.1

Middle AR02450 35.831196 -116.223315 Sedge Phragmites Phragmites 25 - - 145 3.5 21.7

Middle AR02463 35.831074 -116.22329 na Typha/Phragmites Typha 25 Phragmites 25 255 3.8 21.7

Middle AR02475 35.830973 -116.223313 na Typha Typha 20 - - 175 5.7 21.7

Middle AR02488 35.830888 -116.223255 na Typha Typha 50 - - 475 2.8 22.2

Middle AR02500 35.830753 -116.223266 Sedge Phragmites Phragmites 5 - - 250 5.7 21.1

Middle AR02513 35.830594 -116.223275 na Typha Typha 30 - - 185 2.2 21.7

Middle AR02525 35.83049 -116.223342 na Sedge Sedge 50 - - 190 3.3 22.2
18 

Dominant vegetation type 2014 vegetation percentage of cover

2014 stream 

characteristics

Reach Station Latitude Longitude 2010 2014 Veg 1 Density 1 Veg 2 Density 2

Depth 

(mm)

Width 

(m)

Temp 

(°C)

Middle AR02550 35.830335 -116.223534 Sedge Sedge Sedge 50 - - 395 2.7 21.7

Lower AR02600 35.829833 -116.22344 Sedge Phragmites/Sedge Phragmites 50 Sedge 50 340 2.4 21.7

Lower AR02650 35.82938 -116.223378 Sedge Sedge Sedge 15 - - 215 4.6 21.1

Lower AR02700 35.829081 -116.222939 Sedge Phragmites/Sedge Sedge 15 Phragmites 15 335 4.7 21.1

Lower AR02750 35.828843 -116.222487 Sedge Phragmites Phragmites 10 - - 130 4.8 21.1

Lower AR02800 35.828506 -116.222212 Sedge Sedge Sedge 15 - - 150 5 21.1

Lower AR02850 35.828213 -116.221797 Sedge Phragmites Phragmites 90 - - 320 1.8 20.0

Lower AR02900 35.827933 -116.221378 Sedge Sedge Sedge 90 - - 168 1.7 20.0

Lower AR02950 35.827814 -116.220805 Sedge Sedge Sedge 100 - - 148 2.3 18.9

Lower AR03000 35.827416 -116.2203 Sedge Sedge Sedge 90 - - 152 4.3 18.9

Lower AR03050 35.827172 -116.220044 Sedge Sedge Sedge 30 - - 140 1.7 18.3
Publishing support provided by the U.S. Geological Survey

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For more information concerning the research in this report, contact the

 Director, Western Fisheries Research Center

U.S. Geological Survey

6505 NE 65th Street

Seattle, Washington 98115 

http://wfrc.usgs.gov/
Hereford—Relative Distribution and Abundance of Fishes and Crayfish in 2010 and 2014 Prior to Saltcedar Removal, Amargosa River Canyon, California—Open–File Report 2016–1112

ISSN 2331-1258 (online)

http://dx.doi.org/10.3133/ofr20161112