Selected Aspects of the Natural History of the Desert Sucker

[ (Pantosteus)- clarkii]

by

Craig Stephen Ivanyi

A Thesis Submitted to the Faculty of the SCHOOL OF RENEWABLE NATURAL RESOURCES

In Partial Fulfillment of the Requirements

For the Degree of MASTERS OF SCIENCE WITH A MAJOR IN WILDLIFE AND FISHERIES SCIENCE

In the Graduate College THE UNIVERSITY OF

1989 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of the source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his/her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED:

APPROVAL BY THESIS COMMITTEE

This thesis has been approved on the date shown below:

Charles D. Ziebell, Thesis Director Assistant Unit Leader, Arizona Cooperative and Wildlife Research Unit

0. Eugene Maughan Unit Leader, Arizona Cooperative Fish and Wildlife Research Unit

William J. Matter Associate Professor of Fisheries Science iii ACKNOWLEDGEMENTS I wish to express my gratitude to Charles D. Ziebell for his guidence and suggestions throughout this study. I also thank William Matter and Gene Maughan for their help in the development of this project and preparation of thsi manuscript. My thanks also go to Carol Ivanyi, Hugh

McCrystal, and Lynn Ramsey for their ideas, field assistance as well as much needed mental support. Many others assisted with aspects of this study, and to them I owe many thanks; Field assistance: Cord Ivanyi, Marcy Owens, Don Davison, Laura Duckett, Rick Roy; Art and photography: Kelly Ivanyi and Ken Wintin; Advise: James Jarchow D.V.M. and Jeff Hill. This project was supported by the Arizona Cooperative

Fish and Wildlife Research Unit, which is maintained by The

University of Arizona, the Arizona Game and Fish Department, and the U. S. Fish and Wildlife Service. TABLE OF CONTENTS Page

LIST OF FIGURES ...... v

ABSTRACT ...... vi INTRODUCTION ...... 1

DESCRIPTION OF STUDY AREAS ...... 4

METHODS ...... 7

RESULTS ...... 9 DISCUSSION ...... 15 CONCLUSIONS/MANAGEMENT IMPLICATIONS .... 20

LITERATURE CITED ...... 23

APPENDIX A ...... 26 V

LIST OF FIGURES

Figure Page 1. Length-Weight Relationship Curve ...... 10 2. Length Frequency Histogram ...... 12 3. Catostomus (Pantosteus) clarkii Color Phases . 13 vI ABSTRACT

Selected aspects of the Desert sucker's [Catostomus (Pantosteus) clarkii] life history wereexamined in 4 S.E. Arizona streams. Habitat use, reproduction, age class structure, and diet were analyzed from field data obtained from April 1987 through October 1988. Dietary analyses showed that adults fed primarily on plant matter, while fry fed almost exclusively on diatoms. Aging of suckers by scales (Bass and specimens) was not possible. Length frequencies were too evenly distributed to determine age class structure for the populations studied. In 1988 ovary and teste development occurred late January through

April, with spawning commencing in May. Habitat availability and use were found to be important components of the sucker's life history; presumably having an impact on all other aspects of its existence. Deterioration or loss of suitable habitat is reducing the range of the desert sucker due to reductions in and manipulations of surface waters.

VI 1

INTRODUCTION Arizona's native ichthyofauna has been adversely influenced by increasing human demand on the environment.

As a result of introduction of exotic species and manipulation of available waters, many species face a tenuous existence and/or future (Minckley, 1973). Impoundments, diversion and pumping of underground aquifers have mediated or accelerated the threats to many of our native (Minckley, 1973; Hastings and Turner, 1965).

Habitat degradation in southwestern U.S. deserts and surrounding areas has reduced endemic fish populations resulting in extinctions and endangerment to those that survive (Naiman and Soltz, 1981). Currently 25 of 35 native species are listed by Arizona Game and Fish as threatened, 15 of these are federally listed as threatened or endangered (Hendrickson and Simons, 1983). Many of the smaller rivers and creeks of Arizona are now dry except during periods of high precipitation or snowmelt (Minckley, 1973). As a result dry, shifting washes with little or no fish habitat have replaced lush cienegas where fish were abundant (Hendrickson and Simons, 1983). According to the

United States Bureau of Reclamation (U.S.D.I. B. of R.,

1975), human demands for water do, and will continue to, exceed current supplies. Bureau figures show that demands are increasing as Arizona's population continues to grow.

This water depletion certainly will put additional pressure 2 on Arizona's remaining native fishes. Depleting the

available habitat before the specific biological requirements of these species are known further increases the chance of irreparable damage to native fish populations.

One of these native fishes is Catostomus (Pantosteus)

clarkiil, known commonly as the desert sucker (Eddy and

Underhill, 1978). This sucker is found in the drainage below the Grand Canyon, the system of Arizona (which includes Southern Arizona) and New Mexico, and the Virgin and the White Rivers of Utah and Nevada (Eddy and Underhill, 1978). This fish attains standard lengths up to 325 mm and can be identified by its subterminal mouth with large lips and small papillae on the

lower lip and oral face of the upper lip. A cartilaginous sheath on the lower jaw, which is used for scraping, and

darkening of the peritoneum are considered to be

adaptations associated with an herbivorous lifestyle; thus, the desert sucker is viewed as a highly specialized product

of Pantosteus evolution (Smith, 1966; Smith and Koehn, 1971). A limited amount of information is currently available on

1 1 I adopt the "ii" ending, for _(2,...„) clarkii, in accordance to the International Code of Zoological Nomenclature (1964), article 32, page 35, letter "a", regarding "original spelling" of scientific names. 3 the natural history of the sucker. Mpoame (1982) and Wier et al. (1983) examined its parasites in , Arizona. Lowe et al. (1967) studied tolerance to low oxygen tensions for the sucker and Siebert (1980), Meffe (1987), and Bestgen et al. (1987) documented movements in Arizona and New Mexico streams. Several authors have examined its distribution (Armantrout, 1983; Barber and Minckley, 1966; Cross, 1985; Deacon, 1983; Kepner, 1979; McNatt, 1983). Fisher et al. (1981) found the sucker to be herbivorous, feeding heavily on epipelic diatoms in Sycamore Creek, Arizona. They, along with Williams and Williams (1982) noted crepuscular peaks in the sucker's feeding behavior. These previous studies leave much to be learned about other life history aspects of the sucker. The purpose of this study was to obtain information on age class structure, length-weight relationships, reproduction and fecundity, and habitat use. This additional data will provide a better understanding of the species and hopefully increase the chance of ensuring its future. 4

DESCRIPTION OF STUDY AREAS The four streams in southeast Arizona studied were

O'Donnell Creek, the Babocomari River and Bass , all tributaries of the San Pedro River; Sonoita Creek, a tributary of the Santa Cruz River was the main

study site. These streams are all relatively small first or second order streams, with typical riparian zone trees

(cottonwoods, willows, ashes, etc.) O'Donnell Creek consists of shallow (7.5-15 cm deep), narrow (<1 m) riffles

and pools of various sizes (most <0.5 m deep and

1-2 m in diameter). Slow-moving water traverses smooth bedrock and fine sand and silt substrates. The creek flows northeast from to the Babocomari River (T21S,

R18E; to T21S, R19E). The sampling site was at an elevation of 1600m. Thick streamside vegetation is made up

of grasses, rushes and horsetail (Eguisgtum sp). The Babocomari River originates at an elevation of -1500 m in a grassy cienega. This very slow moving stream

is characterized by small riffles (7-15 cm deep, <0.5 m

wide) and small almost motionless pools (0.25-1 m deep, 1-2 m in diameter). A few pools of up to 3 or 4 m deep and 5 m

in diameter existed as well. Substrates consist mostly of

silty muddy sands and some small boulder/cobble areas. A man-made dam exists near the Babocomari Ranch House, which forms a pond approximately 20m in diameter. The pond is

surrounded by rushes and sedges. This perennial stream 5 flows east from near Elgin to Fairbank (T20S, R18E to T20S, R21E).

Bass Canyon Creek runs south froi the Galiuro Mountains to the Muleshoe Ranch (T11S, R21E to T12S, R21E) where it joins Hot Springs Creek at an elevation of 1300 m.

Substrates include cobbles and boulders with some sandy bottomed pools. Riffles vary from 3 cm to 0.5 in deep and

1-6 in wide. Large pools (0.5-1.75 m deep, and up to 5 or 6 in long) are quite common, many with undercut roots, fallen

tree limbs and trapped twigs and leaves lying above or at

the water surface (concealing much of the pool.) Bass Canyon Creek is the largest of the four streams sampled. Sonoita Creek originates in the Santa Rita Mountains near

the town of Sonoita (T20S, R16E) and flows southwest to the Santa Cruz River (T22S, R13E) via Patagonia Lake, a man- made reservoir. The perennial portion of the stream begins

at the town of Patagonia (T22S, R16E) and is made up of groundwater as well as treated municipal wastewater. These sources provide a mean discharge of 7300 cfs from 1965-67

(United States Geological Survey, 1975). The study site was located on the Circle Z Ranch at an elevation of 1350 in

and was over 1.1 km long. The upper creek was characterized by long shallow riffles and a number of pools (see Appendix A for pool descriptions.) Pools varied considerably in size and substrate composition, but

commonly had fallen tree limbs, twigs, leaves, etc. 6

(collectively referred to as debris from this point forward) at or above the water surface which concealed

large portions of the pools below. Streamside vegetation consisted of emergent grasses as well as some small

emergent broadleaf plants. The creek below the dam was characterized by slow-moving, murky water, silt/mud covered gravels, lack of pools and reduced riparian vegetation. 7 METHODS Field work began in May 1987 and was completed in October 1988. One or two trips per month were made except for mid summer 1988 when field trips were curtailed because of heavy precipitation and flooding. Water temperature and dissolved oxygen were measured with a Yellow Springs Model 54-A oxygen-temperature meter. Readings for pH were made using a portable VWR digital pH meter. Hydrogen-ion concentration (pH) water and air temperature, and weather conditions were measured on each trip, but dissolved oxygen was analyzed on an intermittent basis. Habitat use was based on fish observed or captured by electroshocking with a Smith-Root Mark VII backpack electroshocker. Most fish were observed and released, but an average of 10 fish per month were collected. The suckers were placed in a cooler, filled with chilled water from the stream and transported to the University of Arizona where they were weighed and measured. Total length was measured to the nearest millimeter with a measuring board and weights were recorded to the nearest gram using an OtHaus digital scale. Digestive tracts and reproductive organs were removed. Dissected organs and fish (from Sonoita Creek) were preserved and numbered for cross-reference. Fish from Bass Canyon Creek were frozen and later examined for dietary and reproductive analyses. Sonoita Creek suckers and dissected organs were preserved 8 in 10% formaldehyde solution for at least 24 hrs. and then transferred to either 70% ethyl alcohol or 70% Isopropyl alcohol. Sex was confirmed and gonad volume was measured using a graduated cylinder for large specimens and a 6 cc syringe for small ones. Fecundity was determined by counting a subsample of eggs from a known volume, from 11 fish collected during the spawning season (February through May), and estimating a total by multiplying the known

subsample by a factor to achieve the total volume for each fish. Stomachs were removed (esophagus to first loop of

intestine) from three groups of 10 fish, one each from

winter, spring and summer seasons. Contents were identified where possible by microscopic examination.

Scales were removed from the left dorsolateral side near

the lateral line, anterior to the dorsal fin. Scale

imprints from them were made on plastic slides with a scale

press. These imprints were then examined visually using a Model 60-A Bioscope. On July 15, 1988, 61 fish from Sonoita Creek were

collected, weighed, measured and released. This data was used for determining age class structure of the sucker

population. In addition, a Length-weight relationship curve was established with these suckers by graphing weight

(in grams) vs. total length

(in millimeters.) 9

RESULTS Preliminary data was taken from four streams but most of the data was obtained from upper Sonoita Creek. O'Donnell Creek and the Babocomari River had low numbers of fishes and Bass Canyon Creek could not be sampled adequately due to logistical complications. Water quality was acceptable for desert suckers in upper

Sonoita Creek throughout the study period. Water temperature reached a minimum of 9°C on December 14, 1987 and a maximum of 320C on July 15, 1988. Dissolved oxygen was at or near saturation and pH ranged from 6.5 to 8.6 during the study period. A total of 93 suckers were collected and preserved.

Stomach analysis of 30 of these fish (10 each from winter, spring, and summer) showed that the dominant food was unidentifiable plant matter (presumably algae), although significant numbers of diatoms were present (10-20%).

Young-of-year stomachs contained -70% diatoms and unidentifiable plant matter. A Length-weight relationship curve (Figure 1) from the 61 fish captured and released on

July 15, 1988 shows that the suckers ranged from 35 mm to 150 mm total length and 1 g to 37 g body weight. Most fish were between 95 mm to 125 mm (TL) ( 10 g to 22.5 g body weight.) Scales from 15 of the preserved suckers were examined by

Bioscope. No annuli were apparent on the scales examined 11

but (Figure 2) two size groups were evident: Suckers 31- 70 mm in length and individuals from 81-150 mm long.

In 1988, the spawning season began in May after a four month period of enlarged gonads (late January through April.) Males exhibited prominent caudal and anal fin tubercles as well as a horizontally striped color pattern

(Figure 3) February through mid April, 1988. Concurrently,

gonadal volume was an average of 0.33 ml (range 0.1 to 1.0 ml) dropping to an average of 0.036 ml (range 0.0 to

0.08 ml) in late April. Female gonadal volume was an average of 1.28 ml (range 0.1 to 4.2 ml) during the February-April, 1988 period and dropped to 0.096 ml (range 0.04 to 0.12 ml) in May. Gravid females yielded an average of 1,140 eggs (range 450-2,772)

1-2 mm in diameter during the reproductive season. Fry were first collected in June, 1988. Observations from the field study revealed that the smallest suckers had the same physical appearance as adult fish. Almost all (97.3%) suckers were located and captured in pools and rarely found in riffles (2.7%). This observation is interesting since pools represent only 3% of the study area . Of the total number of suckers captured, 68% were located in debris pools (those with overhanging limbs and collected twigs, leaves, etc.), 13.5% in under undercut banks, 11% in backwaters (almost all fry), and 4.5% in open, deeper pools. Pools that suckers occupied differed 13

Catostomus (Pantosteus) clarkii Color Phases

a.

b.

C.

Figure 3. (a) represents normal coloration for males and females. (b) and (c) depict two patterns that males exhibited during the breeding season. 4

markedly in size, varying from: 1.2-9.5 m in length, 0.3- 2.7 in in width, and 7.6-99.1 cm in depth. Pool substrate varied as well, from almost all sand to 30 or 40% cobble

mixed with sand and gravel. Pools inhabited by adults did

not have silt or mud substrates, but those used by fry did. 15 DISCUSSION

Habitat availability is an important aspect to sucker's and could be paramount in future survival of the species.

DIET Dietary analyses yielded limited information because stomach contents were not always recognizable. Microscopic examination confirmed that the desert sucker was primarily herbivorous and fed on diatoms. I observed suckers feeding off of rocks and gravel, apparently removing attached algae

and associated organisms, in both Bass Canyon and Sonoita Creeks. Usually numerous suckers fed as a group in the same area and sometimes on the surface of the same boulder. This observation agrees with Schrieber and Minckley (1981)

who reported that the sucker fed primarily on diatoms in

Aravaipa Creek. In Bass Canyon Creek, suckers were generally observed feeding off of larger rocks and

boulders, perhaps because it was easy to scrape diatoms from the large hard surfaces. None of the dissected suckers from Bass Canyon Creek had empty stomachs and only one sucker's stomach from Sonoita Creek was empty. Young fish fed heavily on diatoms. Adults probably ate proportionally fewer diatoms, however this conclusion is

speculative since a large percentage of adult stomach contents was unidentifiable plant matter. 16

AGE CLASS STRUCTURE Suckers could not be aged, because annuli were not

evident. In many cold-water areas, fish growth stops in winter and an annulus forms. Unfortunately, desert suckers

do not experience extreme differences in winter and summer temperatures in Southern Arizona, therefore growth is even

and scales do not show clear annuli. I attempted to identify age groups by length (Figure 2), but there were basically only two groups: young-of-year and everything else. The latter category contained fish ranging from 81

mm to 150 mm total length (TL). This group most likely

contained a number of age classes. REPRODUCTION Desert suckers apparently spawn in May and possibly into the month of June. Spawning was never actually observed, therefore the location (e.g. what part of the stream, what type of substrate eggs are laid in or on, what time of day,

etc.) was not defined. Male and female suckers had enlarged gonads as early as

February 1, 1988, well before spawning took place. observed color change, appearance of tubercles on both anal

and caudal fin rays and increased gonad size in males, and

presence of eggs in females (with a concurrent increase in 17 gonad volume) in February remaining so through April. At the same time, male coloration changed from the standard color to a horizontal striped appearance (Figure 3).

Concurrently females began to look very plump indicating the presence of many ova, which was confirmed via

dissection. Color changes or other secondary sexual characteristics were not observed in females throughout the study period. Most previous information concerning this fish's reproductive biology is of a general nature and largely anecdotal. Minckley stated (1973) that, "Spawning

is generally in late winter and early spring, on riffles and in a manner similar to other species of Catostomus." From the data obtained in this study, I know when desert suckers spawn, size of gonads, number of eggs females carried, and secondary sexual characteristics exhibited by males (in Sonoita Creek.) However, much remains to be learned regarding this sucker's reproductive habits.

Further field study (and perhaps laboratory as well) is necessary to obtain these missing pieces of information.

HABITAT USE Desert suckers were found almost exclusively in pools with -80% cover (e.g. visual obstruction from above the water surface) and high water flow in, around and/or through the pools. They seldom occurred in backwaters and rarely frequented riffles. Apparently in the streams studied backwaters and riffles do not provide optimal 18

habitat! Generally, the pools used by adult suckers had a high percentage of visual cover provided by dead, fallen trees with many branches and debris that had become lodged

against the tree. This limb/debris layer formed an upper

'"canopy" that completely hid the fish from view. Some pools lacking canopy but having undercut banks, large rock

piles, and depths of 1 to 1.2 in were also frequented by suckers; however, this type of habitat occurred less

frequently than the fallen tree "debris" type of cover. Therefore, the latter type of pool provided the bulk of

habitat for suckers. Adult suckers were very rarely found in shallow riffles or backwaters, even though some backwaters had a high

percentage of cover. Perhaps the missing constituent was sufficient depth or water flow. Pools with overhead cover

provided the type of habitat desert suckers used, and maintenance of such pools appears to be one key to their

future survival in Sonoita Creek. Fry on the other hand, were almost always found in backwaters or little puddles (water filled depressions 5 to

10 cm in diameter) adjacent to the main riffle. This may be due to many factors. Perhaps sucker fry cannot maintain

position in other parts of the stream due to the strong

current and their small size. Harvey (1987) found this to

be the case with young-of-the-year centrarchids and 19

cyprinids. A seasonal change in habitat use by adult suckers was not

apparent. Each pool sampled contained approximately the same number of fish throughout the year, thus my observations gave no indication of any "migration" or seasonal movement. 20

CONCLUSIONS AND MANAGEMENT IMPLICATIONS Many of the streams previously thought to support desert suckers do not contain high numbers of these fish. Attempts to col lect desert suckers in O'Donnell Creek, the Babocomari River and the Santa Cruz River produced few or no fish. O'Donnell Creek is small with narrow riffles, small pools and relatively slow-moving water. There are few pools with overhanging logs, branches and other debris. Desert suckers were present but in very low numbers. There appears to be little habitat for desert suckers. In three sampling trips to the Babocomari River I captured Smallmouth bass, Micropterus dolimieui; Bluegill, Lepomis macrochirus; Redear sunfish, Lepomis microlophus) but no suckers. These introduced fish can negatively effect native fish populations by predation. Furthermore, the very restricted size of the river, extremely slow flow rate, and silt/mud substrate may indicate that this river may no longer provide suitable habitat for desert suckers. The Santa Cruz River lacks good habitat because of lack of pools. Surface water may be ephemeral depending on the amount of rainfall. If desert suckers still exist in the Santa Cruz, the numbers are extremely low. Bass Canyon Creek contained many desert suckers and critical habitat features were present. Upper Sonoita Creek, although not as large as Bass Canyon Creek, also 21 contained numerous suckers and considerable suitable habitat. Both of these streams contain viable populations

of desert suckers. Unfortunately neither stream has direct or continuous flow nor access to downstream rivers. Therefore, groups of suckers that were formerly

interbreeding may become isolated thereby eliminating the

potential for interbreeding and opportunity for genetic exchange. Additionally, these isolated habitats may be reduced even further and a subsequent loss of habitat

quantity and/or quality could result. Protective measures may be required for long-term preservation of this species and its habitat. Desert

suckers withstood natural changes surprisingly well but did not appear to adjust to man-made changes such as the

damming of the Babocomari River or Sonoita Creek. Impoundments may change stream characteristics below dams

(Minckley, 1973). Perhaps slow water flow, settling of fine particulate matter, and changed temperature regimes are the results from impounding these two streams, thus

altering habitat. Man-made changes of our natural waters are a threat to

both quantity and quality of sucker habitat. Natural changes might allow suckers to adapt to them but man-

induced changes tend to affect natural waters very quickly

and radically. The rapidity of these changes preclude adaptation. We need to preserve and enhance this habitat 22 to ensure future survival of desert suckers. One might ask what difference does it make if we lose a species here or there. My answer is, I simply don't know...but perhaps not knowing the consequences is enough. As Leopold said, "The single most important part of being an intelligent tinkerer, is to save all of the pieces." 23 LITERATURE CITED

Armantrout, N.B. "1977" (1983). Additions to Cross' ecological distribution of the fishes of the . Proceedings of the Desert Fishes Council, 9:321-323. Barber, W.E. and W.L. Minckley. 1966. Fishes of Aravaipa Creek, Graham and Pinal Counties, Arizona. Southwestern Naturalist, 11:313-324. Bestgen, K.R., D.A. Hendrickson, D.M. Kubly, and D.L. Propst. 1987. Movements and growth of fishes in the Gila River drainage, Arizona and New Mexico. (In review).

Cross, J.N. 1985. Distribution of fish in the Virgin River, a tributary of the Lower Colorado. Environmental Biology of Fishes, 12:13-21.

Deacon, J.C. "1976" (1983). The native fishes of the Virgin River. Proceedings of the Desert Fishes Council, 8:290-291. Eddy, S. and J.C. Underhill. 1978. How to Know the Fresh- water Fishes. Wm. C. Brown Company Publ.

Fisher, S.G., D.E. Busch, and N.B. Grimm. 1981. Diel feeding chronologies in two Sonoran Desert stream fishes, AgosiA chrysogaster (Cyprinidae) and Pantosteus clarki () Harvey, B. C. 1987. Susceptibility of young-of-the-year fishes to downstream displacement by flooding. Transactions of the American Fisheries Society, 116:851- 855.

Hastings, J.R. and R.M. Turner. 1965. The Changing Mile. University of Arizona Press, Tucson, Arizona.

Hendrickson D.L. and Simons. 1983. The long hard swim. Wildlife Views, February, 1988:4-7.

Kepner, W.G. "1979" (1980). Fishes of the Upper Bill Williams drainage, Mohave and Yavapai Counties, Arizona. Proceedings of the Desert Fishes Council, 11:93

Lowe. C.H., D.S. Hinds, and E.A. Halpern. 1967. Experimental catastrophic selection and tolerances to low oxygen concentration in native Arizona freshwater fishes. Ecology, 48:1013-1017. 24 McNatt, R. "1973" (1983). Status of the native Arizona fishes of Aravaipa Creek. Proceedings of the Desert Fishes Council, 5:116-117. Meffe, F.K. and W.L. Minckley. (1987). Persistence of stream community assemblages: pattern bs. causality. Unpublished mimeographed report. Minckley, W.L. 1973. Fishes of Arizona. Sims Printing Company, Inc. Phoenix, Arizona. Mpoame, M. 1982. Ecological notes on parasites of fishes from Aravaipa Creek, Arizona. Journal of the Arizona- Nevada Academy of Science, 17:45-51. Naiman, R.J. and D.L. Soltz. 1981. Fishes in north american deserts. Wiley Publishers, New York. Schrieber, D.C. and W.L. Minckley. 1981. Feeding inter- relations of native fishes in a Sonoran Desert stream. Great Basin Naturalist, 41:409-426. Siebert, D.J. 1980. Movements of fishes in Aravaipa Creek, Arizona. M.S. Thesis, Arizona State University, Tempe, Arizona.

Smith, G.R. 1966. Distribution and evolution of the North American catostomid fishes of the subgenus Pantosteus, Genus Catostomus. Misc. Publ. Mus. Zool. University of Michigan, 29:1-132. • Smith, G.R. and R.K. Koehn. 1971. Phenetic and cladistic studies of biochemical and morphological characteristics of Catostomus. Systematic Zoology, 20:282-297.

United States Department of the Interior Bureau of Reclamation. 1975. Westwide Study Report on Critical Water Problems Facing the Eleven Western States. Reproduced by National Technical Information Service. U.S. Department of Commerce, Springfield, Virginia. United States Geological Survey. 1975. Surface water supply of the United States, 1966-70. Geological Survey Water Supply Paper 2126. Wier, W. 1983. Parasites of fishes in the Gila River drainage in Southwestern New Mexico. Journal of Wildlife Diseases, 19:59-60.

Williams, C.D. and J.E. Williams. 1982. Summer food habits of fishes from two springs in east-central Nevada. 25

Southwestern Naturalist, 27:437-445. Appendix A 26

Sonoita Creek Pool Description

Pool # Length Width Depth Substrate Type of Cover

1 4 m 3 In 1.3 in 20G80S* open

2 1 in 0.3 in 0.7 in 30G70S undercut bank

3 3.1 in 0.7 in 0.5 in 30G70S undercut bank

4 4 in 1 in 0.5 in 20C10G7OS undercut roots

5 8 in 1.1 in 0.7 in 40G60S debris,(bkwtr)

6 7 in 1 in 1 in 10C20G7OS debris

7 7 in 1.5 in 0.7 in 10B20C30G4OS debris,rocks

8 11 in 1 in 1 in 40G60S undercut bank

9 4 in 2 in 0.3 in 25G75S debris

10 1 in 0.7 in 0.2 in 40G60S debris

11 4 in 0.7 in 0.7 in 30G70S debris

12 7 m 2-2.5 in 0.5 in 10C20G7OS open (bkwtr)

13 12 in 1-2 in 0.3 in 10B20C20G50S debris

14 10 in 1-1.1 in 0.25 in 50G5OS debris

15 7 in 1-1.5m 0.12-0.4m 10B30C20G4OS debris

* Note-substrate numbers represent percentages; m=meters, B=boulder, C=cobble, G=gravel, S=sand, bkwtr=backwater. - (n) J- 10 g»

, L(00-4--

I

CR.,143 TOZTI„T;