THE UNIVERSITY OF ARIZONA

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1 PRESENCE OF FISH IN IRRIGATION DIVERSIONS FROM THE VERDE RIVER AND WET BEAVER CREEK, ARIZONA by Richard Roger Roy A Thesis Submitted to the Faculty of the SCHOOL OF RENEWABLE NATURAL RESOURCES In partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE WITH A MAJOR IN WILDLIFE and FISHERIES SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 1989

2 2 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 acknowledgement 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: +(_ta)c( APPROVAL BY THESIS COMMITTEE This esis has been pproved on the date shown below: (--\\ CHARLE D. ZIEBELL, hesis Director Date Assistant Unit Leader, Arizona Cooperative Fish and Wildlife Research Unit O. EUGENQ MAUGHAN Unit Leader, Arizona Cooperative Fish and Wildlife Research Unit,// gie 9 Date (11-)/ _ WILLIAM J. MATTER( Associate Professor of Fisheries Science / - Date

3 3 ACRNOWLDEGEMENTS I would like to thank my advisor Charles D. Ziebell, and my committee Dr. O. Eugene Maughan, and Dr. William J. Matter for their guidance, patience, and advice during the field and writing portions of my research. I would also like to acknowledge the following people for their assistance in the field: Julie Urman, Greg Taylor, Brent Bibles, Paul Barret, Marty Jakle, and Selso Villegas. Their hard work and enthusiasm was invaluable in making this project a success. Special and sincere thanks go to Stacey Copley for the long hours she spent typing drafts of the thesis. Enough cannot be said of my deep appreciation. Finally, I thank my parents who's support, moral and otherwise, helped me reach a personal goal. Project of Arizona Cooperative Fish and Wildlife Research Unit - cooperatively sponsored by, Arizona Game and Fish, University of Arizona, and the U.S. Fish and Wildlife Service.

4 4 TABLE OF CONTENTS ABSTRACT page 7 INTRODUCTION page 8 DESCRIPTION OF STUDY AREA page 11 MATERIALS AND METHODS page 17 RESULTS page 20 DISCUSSION page 28 LITERATURE CITED page 36

5 5 LIST OF ILLUSTRATIONS Figure 1. Diagram of RS Diversion and Wet Beaver Creek. Figure 2. Diagram of OK Diversion and the Verde River.

6 6 LIST OF TABLES Table 1. Relative Abundance of Fish Captured in RS Diversion and Wet Beaver Creek. Table 2. Length Frequencies of Fish Captured in RS Diversion and for Smallmouth Bass in Wet Beaver Creek. Table 3. Relative Abundance of Fish Captured in OK Diversion and Verde River. Table 4. Length Frequencies of Fish Captured in OK Diversion.

7 7 ABSTRACT Large amounts of water are diverted from the Verde River and Wet Beaver Creek for agricultural irrigation in the Verde Valley. Fish populations in two irrigation diversions were sampled and fish were collected during a one year period to determine habitat suitability, the relative abundance, and fate of fishes. The most abundant species found in these diversions were red shiners and smallmouth bass. Irrigation diversions generally did not provide habitat suitable for fish and did not support large fish communities. Frequent drawdowns and irrigation of fields limited the amounts of suitable habitat in the diversions. Most fish present in the diversions during drawdowns became stranded in shallow pools and were subject to predation by raccoons, herons, kingfishers and man.

8 8 INTRODUCTION There is concern over the effect of irrigation diversions (e.g. channels, ditches) on fish populations. Clothier (1953, 1954) studied fish losses associated with irrigation diversions of the West Gallatin River, Montana and determined that large populations of salmonids, catostomids and cottids were present in diversions. Clothier (1953) estimated that in 1951, 2,835 legal gamefish weighing 1,186 pounds (trout 7 inches or larger) were lost in 11 irrigation diversions. Hallock and Van Woert (1959) found that in the Sacramento and San Joaquin Rivers of California, few juvenile salmon entered diversions because migrations occurred before the irrigation season began, but that some adult fish did enter diversions on upstream migrations. In the arid southwest, some irrigation diversions may offer valuable aquatic habitat and contain substantial populations of desirable gamefish as well as several endemic species, some of which are on the Endangered Species List or are Species of Special Concern (Marsh and Minckley, 1982). For example, Brooks (1984) showed that survival of an introduced population of the endangered Gila topminnow (Poeciliopsis o. occidentalis) in Seven Springs, Arizona was dependent upon the use of a diversion to escape floods.

9 9 The Verde River is the major stream that drains the area between the Mogollon Rim and the Black Hills (Owen- Joyce and Bell, 1983). This river originates in the Big Chino Valley, north of Prescott, Arizona, and is a tributary of the Salt River (Verde River EIS, 1981). The Verde River and its tributaries, including Wet Beaver Creek, are used as a source for the irrigation of 778 acres in the Verde Valley (Northern Arizona Council of Governments, 1979). There are at least eight major irrigation diversions on the Verde River (M. Jakle, B.O.R., personal communication). The Verde River contains substantial populations of smallmouth bass (Micropterus dolomieui), channel catfish (Ictalurus punctatus) and flathead catfish (Pvlodictis olivarus). The roundtail chub (Gila r.robusta) is endemic to the Verde River and reproducing populations exist in the headwaters. Native fish enthusiasts view the Verde as important for native fish preservation, but it is also important for sport fishing. Anglers interviewed during the study indicated that they preferred to fish for catfish and smallmouth bass. Wet Beaver Creek is primarily managed as a trout fishery. Rainbow trout (Oncorhvnchus mvkiss) are stocked by Arizona Game and Fish. Smallmouth bass are abundant and roundtail chub are common. Wet Beaver Creek is an

10 1 0 important recreational area and fishing is a major activity. Little is known if the irrigation diversions on the Verde River and Wet Beaver Creek are providing habitat for game and nongame fish, or if they are contributing to the decline of fish populations. The purpose of this study is to document the occurrence of fish species within two irrigation diversions; to determine if they offer suitable habitat for fish; and to determine the fate of fish that enter and remain in the diversions. This information will help determine if practical management procedures and maintenance activities can be used to enhance fish populations, or to protect existing fish populations.

11 1 1 DESCRIPTION OF STUDY AREA The Beaver Creek drainage basin is divided into two major sub-basins, Wet Beaver Creek and Dry Beaver Creek. Wet Beaver Creek originates from springs in Sec 14, T 15N, R 7E, (Figure 1). The two creeks join at McGuireville, Arizona and form Beaver Creek, a tributary of the Verde River. The flow in Beaver Creek is fully or partially diverted for irrigation in the vicinity of Montezuma Castle National Monument (Owen-Joyce and Bell, 1983). Ranger Station (R.S. Diversion) The area studied is approximately 12.8 km north of Montezuma Castle National Monument at the Beaver Creek Ranger District of the Coconino National Forest. The Ranger Station (RS) irrigation diversion from Wet Beaver Creek is 1.6 km long. The water is used to irrigate three pastures and to fill stock tanks at the Ranger Headquarters. The banks of the RS diversion are typically lined with grasses (Gramineae) with an overhead canopy of ash (Fraxinus spp.), sycamore (Platanus occidentalis) and cottonwood (Populus deltoides). Unmodified regions of Wet Beaver Creek near the diversion have a gravel-boulder- bedrock substrate. The habitat consists mainly of pools and riffles.

12 Figure 1. Diagram of RS Diversion and Wet Beaver Creek 1?

13 13 The banks are lined with large cottonwoods and sycamores. Maximum depth recorded was 60 cm and maximum width was 10 m. A dam, 15 m long and up to 60 cm high, diverts water into the RS diversion. The dam is constructed of boulders and gravel from the stream bed. Winter rains and heavy run-off produce high stream flows which usually breach the dam (Bill Stafford, U.S. Forest Service, personal communication). After the dam is breached water does not flow into the diversion until repairs are made. The dam also creates a diversion pool 110 m long, up to 22 m wide and 1 to 2 meters deep. The substrates found in the pool are mostly sand, gravel and boulders. Root wads, undercut banks and overhanging trees are found along the shore of the pool. The entrance of the RS Diversion is 6.5 m wide and 30 cm deep. The first 110 m of the diversion contains three habitat types. Pool-riffle habitat constitutes the first 35 in with depths near 30 cm and width of up to 5 m. A pool 35 in long, 5 in wide and up to 1 in deep, follows the pool- riffle habitat. This pool contains boulders, undercut banks and root wads. The remaining 35 in is similar to the majority of RS diversion, run habitat, up to 1 in wide, 30 cm deep. Water column velocities usually were < 1 ft/sec, and there was little instream cover.

14 14 O.K. Diversion OK Diversion is located about 1 km below the confluence of Oak Creek and the Verde River and is about 4 km long (Figure 2). The water is used to irrigate crops for several ranches and the Yavapai-Apache Indian Reservation. The banks are 1-3 m high and steep with few undercuts. The diversion is lined with large and sapling willow (Salix spp.), cottonwood, some sycamore and ash, and overhanging grasses. A diversion pool, approximatly 1 km long, about 100 m wide and from 0.3 to 2 m deep is created by the diversion dam. The banks of the pool in some areas are steep 1 to 2 in high, unstable with few large trees. Upstream of the diversion pool, the Verde River has a sand-gravel subsrate. The habitat consists of deep pools, riffles and runs. The maximum depth recorded was 2.5 m, with a width of 30 m. The banks are a mix of sand, grasses and willow sprouts. The diversion dam is approximately 100 m long and 1.5 in high diverts water into the canal. The dam is constructed of large boulders and cobble. Winter rains and heavy run-off produce high stream flows that causes extensive damage to the dam. The entrance of the diversion is 12 in wide and 2 in deep. The first 100 in of the diversion is 1-2 m deep. The left bank is steep, at least

15 Figure 2. Diagram of OK Diversion and the Verde River 15

16 16 2 in high, and unstable; the right bank is a conglomeration of boulders, logs and other material added for reinforcement. Below the first 100 in the diversion is composed of run habitat, 2-3 m wide and up to 1 m deep. Water velocities vary slightly but are usually < 1 ft/sec. There is little instream cover. The substrate varies from silt to gravel. Usually in late fall, water flow is deliberately reduced in the diversion with a headgate and unused water is returned to the river. Only enough water is allowed to flow to support livestock and minor irrigating (G. Kavochovich, rancher, personal communication). The headgate is located approximately 300 in below the mouth of the diversion. Therefore, the first 300 m of the diversion almost always has flowing water. During mid-february water flow is completely halted for at least two weeks. After this period, bulldozers and backhoes are used to remove accumulated sediments and debris from the diversion and the dam is also repaired. When maintenance is complete, water is again allowed into the diversion. During the growing season, sections of the diversion are partially de-watered on a weekly basis because the water is turned out into the fields. Also, if repairs are necessary, portions of the diversion will be drawndown.

17 17 MATERIALS AND METHODS The Ranger Station and OK diversion were sampled once during each of the five periods from October 1987 to August These periods, October 1 to November 31, December 1 to February 28, March 1 to April 30, May 1 to June 30 and July 1 to September 30, coincided with climatological patterns and agricultural practices rather than calendar season. An attempt was made to relate the relative abundance of fish in diversions with season but water manipulation made it impossible to use the same sampling techniques from season to season. Ranger Station (R.S. Diversion) Four 100 m long stations were established along the length of the diversion; Station I, the first 100 m of the diversion, Station II, 0.3 km downstream of Station I, Station III, 0.8 km below Station I, and Station IV, the last 100 in of the diversion. A 0.6 cm mesh seine was used to block the escape of fish and a Smith-Root backpack shocker was used to collect fish. Each station was sampled with a single pass of seine or electrofishing. Captured fish were identified, measured to the nearest millimeter and released in the vicinity of capture. Species composition and relative abundance were determined for each period, and for the entire study.

18 18 In August of 1988, The diversion pool and the unmodified stream were sampled to determine fish species present in the vicinity of the diversion. Electrofishing was conducted along 120 in of shoreline. Trammel netting (20 in x 1.86 in x 3.8 cm mesh) was conducted for a 12 hr nighttime period in the deepest section of the pool. A 100 in section of the creek, 50 in upstream from the diversion pool was blocked with seines and electrofished in a similar manner to that used in the diversion. O.K. Diversion Six stations, 100 in long, were established in OK Diversion. Station I, the first 100 in of the diversion. Station II was approximately 300 in below Station I, at the first headgate. Station III on the Kavochovich Ranch, was about 1.6 km below Station I. Stations IV and V, were 0.5 and 1 km respectively from Station III. Station VI, was 1.6 km below Station V, ( Medicine Man Ranch). During periods of full flow, stations were sampled with 2 hr evening trammel net sets, seining or shocking. During periods of reduced or no flow, either seining or shocking was used. The stations were blocked with seines during electroshocking. The diversion pool was sampled twice at night during August 1988 with two 46.5 m x 1.86 in six-panel experimental gill nets set for 12 hrs. Each panel was

19 m, and mesh sizes were 2.6 cm, 4 cm, 5.2 cm, 6.5 cm, 7.8 cm and 9.1 cm. The nets were anchored to shore, one with the smallest mesh near shore, the other with largest mesh near shore, and placed at approximately 45 degree angles across the current. Two areas of the river upstream from the diversion pool were sampled with trammel nets, seines and electrofishing. One area was Bignotti Beach, 1.6 km above the confluence of Oak Creek. The other area was at the confluence of Oak Creek, 300 in upstream of the diversion pool. Verbal descriptions of habitat and environmental factors in the latest editions of several Habitat Suitability Indices (HSI) were used to evaluate the habitat quality of the diversions. Qualitative comparisons were made between habitat requirements at 50% - 100% of optimal and measured habitats in the diversion during full flow.

20 20 RESULTS The results are given seperately by diversion because of differences in physical features and flow periodicity. RS Diversion Smallmouth bass were the most abundant species in the RS diversion (76%) of all fish captured (Table 1). The majority of bass encountered in the diversion were < 100 mm TL (Table 2). Some individuals > 100 mm TL were found but they were restricted to Station I. In the river in the immediate vicinity (diversion pool and upstream) of RS diversion, smallmouth bass were also the most abundant species (86%) most of these fish were also < 100 mm TL (Table 1,2). Rainbow trout were commonly found in the diversion, (10%) of all fish captured. however only at Station I. The trout, which are regularly stocked by Arizona Game and Fish, ranged in length from mm TL (Table 2). Only a few rainbow trout were collected in the river in the vicinity of the diversion (Table 1). Sonora sucker (Catostomus insicnis) were the second most abundant fish species (12%) found in the diversion. However, they were abundant only during the fall 1987 when both large adults (> 351 mm TL) and juveniles were captured (Table 2). Adult suckers were restricted to

21 21 Table 1. Relative abundance (X) of fish captured in Ranger Station Diversion and Wet Beaver Creek. RANGER STATION DIVERSION SPECIESn Rainbow trout Smallmouth bass Sonora sucker Desert sucker Speckled dace TOTAL WET BEAVER CREEK SPECIES % Rainbow trout Smallmouth bass Sonora sucker Desert sucker Roundtail chub TOTAL

22 9-1 o k ra GJ 0> a) o O - 4J >, 3 en H

23 23 station I but juvenile suckers, when present, were collected throughout the diversion.

24 24 O.K. Diversion Red shiners (Notropis lutrensis) were the most abundant species (69% and 46%) respectively in OK diversion and the Verde River (diversion pool and upstream) (Table 3). Both adult and juveniles were common and could be found throughout the diversion during all times of the year. Smallmouth bass were the second most abundant (10%) fish in the OK diversion (Table 3). However, they were not common in the Verde River near the diversion (Table 3). Most bass were < 100 mm TL (Table 4). Channel catfish occurred in the diversion but the majority were juveniles; only one adult channel catfish was captured. In the river, adult and juvenile channel catfish, made up 9% of the fish captured (Table 3). Adults could were found in the diversion pool near the mouth of the diversion and in pools and riffles upstream of the diversion pool. Flathead catfish were rare in the diversion, (0.7%) of the total number of fish captured (Table 3). However, three of the five flathead catfish encountered were adults, one was > 301 mm TL and the other two were > 451 mm TL. The two remaining fish were < 100 mm TL (Table 4). Flatheads, especially juveniles, were much more common in the river than in the diversion (Table 3).

25 Table 3. Relative abundance (%) of fish captured in OK Diversion and Verde River. 25 OK DIVERSION SPECIES _ n Smallmouth bass Red shiner Mosquitofish Carp Green sunfish Channel catfish Yellow bullhead Flathead catfish Sonora sucker Desert sucker Squawfish Roundtail chub TOTAL VERDE RIVER SPECIES n_ Smallmouth bass Red shiner Carp Green sunfish Channel catfish Flathead catfish Sonora sucker Desert sucker Largemouth bass TOTAL

26 o '0 0 O)o n.? $4-4' 0 1 N itt Pn4o crt 04 0 CO en to 4-1 n n n n. nn CO 0 N rni, ,.."... 0 en Q) 1 N N N E.-4 ("I cs% 4-4 4; 0,-.1 I. N u -n A ei... 1 C4 ezs r n n , H (iei i 4..e 1..e 0.-4 Ch NO N A ta..., n n..1...% 1.4 IN n W N %.0 e.....n ::1 U In 4-4 N N.-.1 N n7),..1 N N N N 4.0 N ' O I 43 a% -4' V:, N in 0 co 0 ".../ -s ill 4.) ' G f t C.14 C.0 cn a 4.1

27 27 Roundtail chubs were not common in the diversion. Most of the chubs were juveniles, but two adults were captured at Station I (Table, 4). No roundtail chubs were found in the river.

28 28 DISCUSSION The two irrigation diversions contained only a small portion of habitat that was suitable far several of the fish species present. Fish were usually found concentrated in isolated areas with undercut banks, rootwads, aquatic vegetation or structures that furnished cover. Clothier (1954) found fish concentrated in similar areas in his study. Ranger Station (RS) Diversion Smallmouth Bass: Optimal smallmouth bass habitat includes but is not restricted to gravel, rubble or boulder substrates, pools >1 in deep and velocities <1ft/sec; and cover in the form of stumps, trees, boulders, and crevices (Edwards et al, 1983). Smallmouth bass occupied this type of habitat in the creek. The first 100 m of RS diversion also had components of optimal smallmouth bass habitat, although much of the habitat in the diversion was unsuitable. Bass, in the diversion inhabited areas beneath undercut banks, or near root "wads" boulders, or overhanging vegetation. The water velocity varied somewhat but was usually <1 ft/sec. Suitable habitat in the diversion may have caused smallmouth bass to remain in these areas and not return to the creek.

29 29 Smallmouth Bass Pools with boulders, logs, undercut banks, trees, and stumps that provide important forms of cover for smallmouth bass (Edwards et al, 1983) were limited in OK Diversion. However, juvenile smallmouth bass were collected near the banks, overhanging and aquatic vegetation. Smallmouth bass habitat was limited throughout OK Diversion. The lack of cover may be one reason larger numbers of smallmouth bass were not found in the diversion. Smallmouth bass were also uncommon in the Verde River in the vicinity of the diversion (especially in the diversion pool). Low bass numbers in the river may have resulted in a lack of pressure to colonize the diversion. Channel Catfish Suitable riverine habitat for channel catfish consists of, but is not restricted to approximately 50% pools, > 20% cover in the form of logs, boulders, cavities, brush, aquatic vegetation, substrates with rubble, gravel, and boulders in riffles (McMahon and Terrell, 1982). Few of these criteria were met in OK Diversion. Channel catfish were not abundant in the diversion. However, a few fry and juveniles were found at nearly all stations. Catfish occupied areas along the banks and under overhanging vegetation.

30 30 Both adult and juvenile channel catfish, were collected in the mainstem of the Verde River and in the diversion pool in habitats similar to those described in the HSI. Flathead Catfish Suitable riverine flathead catfish habitat consists of but is not restricted to: velocities of < 1.5 ft/sec, approximately 10 to 60% riffles (which is important juvenile habitat), areas not dominated by runs, and 25 to 75% pools (Lee and Terrell, 1987). These authors also mentioned that cover in the form of logs, brush piles and undercut banks are important adult cover. Where they occurred in the diversion, adults were found associated with boulders and undercut banks. Juveniles were found near overhanging vegetation along the banks. The relative scarcity of flathead catfish in the diversion is related to the scarcity of their preferred habitats. Flathead catfish were common in the Verde River near the diversion and occupied very similar habitats to those described in the HSI. Roundtail Chub In the headwaters of the Verde River, adult roundtail chubs required deep pools, > 1.5 m, undercut banks, boulders, logs, for cover, eddies with varying

31 31 velocities. Fry and juveniles occupied pools and riffles, and backwaters < 1 in in depth, over silt to cobble substrates, with cover in the form of submerged and overhanging vegetation, and boulders. This type of habitat is found in small isolated portions of the diversion, however much of the diversion is not suitable for roundtail chub. Roundtail chub were uncommon in the diversion and the majority captured were juveniles. However, an adult male in prime spawning condition was captured over a sand and gravel bar (Station I). During later samples juveniles were found in this area. Vanicek and Kramer (1969) found that roundtail chubs spawned over clean sand and gravel substrates. The presence of the adult and juvenile chubs indicates that the chubs may use a portion of the diversion for spawning. However, Cross (1975) stated that roundtail chubs in the Virgin River, Nevada, were rarely associated with irrigation withdrawals. Despite the apparent occurrence of suitable habitat in OK diversion few fish utilized it. Low numbers in the diversion may be the result of roundtail chubs being uncommon in this section of the Verde River. Factors Affecting Habitat Limitations: The major limiting factors relative to habitat within the diversions were the frequent drawdowns brought

32 32 about for winter maintenance, headgate repairs, irrigation of fields and pastures, and water loss because of ocassional vandalism. During a period of reduced or halted flow, the fish present in the diversion retreated to isolated pools. However, many fish perished. Clothier (1953, 1954) found similar responses to drawdowns by fishes in irrigation diversions on the West Gallatin River, Montana. The only fishes he found attempting to go "upstream" during flow reductions were salmonids. Samples from below headgates in the OK Diversion showed no concentration of fish attempting to move "upstream". During periods of reduced flow, raccoons, (Procyon lotor) blue herons, (Ardea herodias) green heron (Butorides virescens) and belted kingfishers (Meqacervle alcyon) fished the isolated pools in the diversions, especially the OK Diversion. In February, 1988, three partially consumed juvenile carp, several dead red shiners, and a floy tag from a tagged Sonora sucker were found in or near a pool. Tracks in the area indicated that raccoons had captured and fed upon the fish. John (1964) found that fish trapped in shallow pools in an intermittent stream in the Chiricahua Mountains, Arizona, were easy prey for raccoons, and to a lesser extent garter snakes (Thamnophis spp.,) and kingfishers. In addition to wildlife predators, human predators walk along the diversions during drawdown in search of

33 33 trapped fish, especially catfish (G. Kavochovich and R. McDonald, ranchers, personal communication). Occasionally large catfish, carp, suckers, and bass are found stranded when the diversions are dewatered. Fish are also sometimes found trapped in the fields or side canals while water was being "turned out" onto the pastures and fields (G. Kavochovich, R. McDonald, and Forest Service staff, personal communication). Another factor affecting fish surviving a drawdown period is the fact that in the winter, bulldozers and backhoes are used to clean sediment and other accumulated debris from the diversions, especially OK Diversion. This activity destroys or alters habitat and cover that would be available to fish during full flow. Many of the pools are destroyed and fish in these pools are probably killed. Management Implications I believe that fish are not swept into the diversions en mass but wander into the canals in search of habitat, or drift into the diversions as fry. Where habitat does not occur, they do not remain. Since little adult fish habitat exists in the diversion few adult fish remain in them. Juvenile and non-gamefish habitat occurs in the diversions, therefore higher numbers of these fish enter and remain in the diversions. Most of these fish are lost to predators or dessication. The low numbers of

34 34 gamefish and roundtail chub present in the diversions make it improbable that their loss has any significant impact on the species. Several approaches to reduce these losses are suggested. The presence of fish only in areas that approach the definition of suitable habitat and their absence from areas of non-suitable habitat suggests that modification is the key to successful fish management in the diversions. If developement of a sport fishery is the objective, then significant improvement of fish habitat will be required. Such an approach would not seem to be cost affective because of frequent dewatering of the diversions and the frequent need to modify the characteristics of the channel. Another management approach would be to reduce the numbers of fish entering the diversions. Costly investments in fish barriers would not seem justified because of the low numbers of fish present in the diversions. Yet another option would be to remove any pockets to optimal habitat within the diversion, this may reduce the numbers of fish remaining in the diversion and thereby reduce the losses of fish during dewatering. My data suggests that large numbers of fish are not lost to these irrigation diversions and large amounts of effort and money need not be spent to rectify the situation. Although the diversions do not provide much

35 fish habitat, they do provide wildlife habitat. The 35 diversions, especially OK Diversion, has well established riparian vegetation. This riparian habitat provides resources for many wildlife species. Such as: gambels quail (Lophortyx gambelli), ring-necked pheasant (Phasianus colchicus), many passerine species (Passeriformes), waterfowl (Anseriformes), and shorebirds (Charadriiformes), raptors (Falconiformes), beavers (Castor canadensis), and raccoons. On one occasion, a peregrine falcon (Falco peregrinus anatum) was seen hunting along an irrigation diversion very near the study site (M. Jakle, B.O.R. personal communication). The riparian vegetation provides habitat for many birds and animals, perhaps the best management alternative would be to leave the situation as is until water allocation issues have been resolved.

36 36 LITERATURE CITED Brooks, J.E Factors affecting the success of Gila topminnow (Poeciliopsis o. occidentalis) introductions on four Arizona National Forests. Office of Endangered Species, U.S. Fish and Wildlife Service, Albuquerque, N.M. Clothier, W.D Fish loss and movement in irrigation diversions from the West Gallatin River, Montana. J. Wildl. Manage. 17(2): , Effect of water reductions on fish movements in irrigation diversions. J. Wildl. Manage. 18(2): Cross, J.N Status and ecology of the Virgin River roundtail chub, Gila robusta seminuda (Ostiechthyes:Cyprinidae). Southwestern Naturalist 23(3): Edwards, E.A., G. Gebhart, and O.E. Maughan Habitat suitability information: Smallmouth bass. U.S. Dept. Int., Fish Wildl. Serv, FWS/OBS-82/ pp.

37 37 Hallock, R.J., and W.F. Van Woert A survey of anadromous fish losses in irrigation diversions in the Sacramento and San Joaquin Rivers. California Fish and Game 45(4): John, K. R Survival of fish in intermittent streams of the Chiricahua Mountains, Arizona. Ecology 45: Lee, L.A., and J.W. Terrel Habitat suitability index models: Flathead catfish. U.S. Fish Wildl. Serv. Biol. Rep. 82(10.152). 39pp. Marsh, P.C., and W.L. Minckley Fishes of the Phoenix Metropolitan Area in Central Arizona. N. Am. J. Fish. Manage. 2(4): McMahon, T.E., and J.W. Terrel Habitat suitability index models: Channel catfish. U.S. Dept. Int., Fish and Wildlife Service. FWS/OBS-82/ pp. Northern Arizona Council of Governments Verde Valley water pollution source analysis: Flagstaff, N. Ariz, Council. Govern. Rep. 148pp.

38 Owen-Joyce, C.K., and S.J. Bell. ND. Appraisal of water 38 resources in the upper Verde River area, Yavapai and Coconino Counties, Ariz. Ariz. Dept. Water Res. Bull. 2, 219 pp. Raleigh, R.F., T. Hickman, R.C. Solomon, and P.C. Nelson Habitat suitability information: Rainbow trout. U.S. Dept. Int., U.S. Fish Wildl. Serv. FWS/OBS- 82/ pp. U.S. Forest Service Verde River, wild and scenic river study report, Yavapai and Gila Counties, Arizona, Environmental Impact Statement. 161pp. Vanicek, C.D., and R.H. Kramer Life histories of the Colorado squawfish, Ptvchocheilus lucius, and the Colorado chub, Gila robusta, in the Green River in Dinosaur National Monument, Trans. Am. Fish. Soc. 98(2):