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UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE Bureau of Sport Fisheries and Wilflife Southwestern Region Albuquerque, New Mexico


Prepared in Cooperation with the Colorado Game and Fish Department September 1957 PREFACE

This report contains a detailed analysis of the effect of Curecanti unit, Storage project, upon fish and wildlife resources in the Valley, Colorado. The information in it is intended for consideration by the Secretary of the Interior in determining whether or not the project is economically justified, as required under the provision in Section 1, Public Law 485, 84th Con­ gress, 2nd Session, which authorized the Colorado River Storage Proj­ ect April 11, 1956. As planned by the Bureau of Reclamation, Curecanti unit will consist of 4 and reservoirs. The area influenced by these faci­ lities will begin at the headwaters of Curecanti Reservoir on the Gunnision River near the mouth of North Beaver Creek, 6 miles west of Gunnison, Colorado. It will extend down the river through Narrow Gauge, Morrow Point, and sites. From Crystal , 37.5 miles downstream from the mouth of North Beaver Creek, effects of the project will extend another 33 miles to the mouth of the North Fork of the Gunnison River. The current plan has been prepared for consideration by the Secretary of the Interior in accord with the above-mentioned provision of Public Law 485. Project data were fur­ nished this Service by the Bureau of Reclamation in letters dated December 1, 1954, June 9, 1955, and May 19, 1957, and by copy of the status report, Curecanti unit, dated February 1956. By preliminary report dated January 18, 1955, contained in a letter to Regional Director Larson, Bureau of Reclamation, Bureau 4, the Fish and Wildlife Service, with the concurrence of the Colo­ rado Game and Fish Department, cited reasons for opposing construction of reservoirs on the Gunnison River above the confluence of the North Fork of the Gunnison River. The adoption of an alternate plan using reservoirs located elsewhere was recommended. In addition to the foregoing report, the U.S. Fish and Wildlife Service has prepared other reports on the Colorado River Storage project and participating projects that refer to the Curecanti (Cottonwood Gulch) Reservoir at the Blue Mesa (Cottonwood Gulch) Dam site. Included in this group ar~ the following:(1) A Preliminary Report on Fish and Wildlife Resources in Relation to the Colorado River Storage project, Colorado River and Tributaries above Lees Ferry, Arizona, January 10, 1949, and (2) A Preliminary Report on Fish and Wildlife Resources in Relation to the Colorado River Stor­ age Project and Participating Projects, January 1951. Personnel of the Colorado Game and Fish Department assisted in field investigations and in providing from departmental files data essential to preparation of this report. BUREAU OF SPORT FISHERIES AND WILDLIFE DESCRIPTION OF THE PROPOSED PROJECT

Project Status 1. The Curecanti unit, consisting of 4 dams and reservoirs on the Gunnison River below the town of Gunnison, Colorado, was provi­ sionally authorized by Congress as a part of the Colorado River -Stor­ age project, April 1956. Provisions limit Curecanti Reservoir to not less than 940,000 acre-feet capacity, or more than a maximum water surface elevation of 7,520 feet 1/. Provisions further stipulate that construction of Curecanti unit shall not be undertaken until the Sec­ retary of Interior has re-examined the economic justification and certified to Congress and the President that, in his judgment, the benefits from such unit will exceed its costs.

Purposes 2. The primary purpose of Curecanti unit is to provide hydro­ electric power. According to the Bureau of Reclamation's Status Re­ port on this unit, dated February 1956, "Benefits to downstream water users from river regulation .•. would not be significant in deter­ mining the unit's economic justification". Location 3. Curecanti Reservoir will be impounded by , the site of which is on the Gunnison River in Gunnison County, Colorado, about 26 miles by road southwest of the town of Gunnison. The reser­ voir will extend upstream to a point approximately 6 miles from the Gunnison city limit. The other 3 proposed reservoirs will be located along a 15-mile reach of deep canyon section of the Gunnison River above Black Canyon of the Gunnison National Monument and above the existing Gunnison Tunnel that diverts from the river to the Uncompahgre reclamation project. will be located farthest downstream, 4 miles upstream from the east portal of Gunnison Tunnel:; will be located on the Gunnison River about 1 mile downstream from the mouth of Cimarron Creek; and Narrow Gauge Dam will be located 7 miles downstream from the town of Sapinero, Colorado, and 3.5 miles downstream from the proposed Curecanti (Blue .Mesa) Dam site.

lf All elevations in this report refer to mean sea level datum. BUREAU OF SPORT FISHERIES AND WILDLIFE Proiect Features Engineering data 4. To date no detailed design for the proposed Blue Mesa Dam has been developed. It has not been decided whether earthfill and rock­ fill or concrete-arch construction will be utilized. A tentative plan provides for an earthfill and rockfill structure with a crest length of 820 feet, 350 feet above streambed. There will be a free-overflow­ type spillway with a crest of 187 feet in length, with a capacity of 31,000 second-feet. Reservoir releases will be accomplished by a pen­ stock outlet, capacity 2,100 second-feet, leading to a powerplant at the base of the dam. The powerplant will consist of 2 generators having a combined capacity of 51,000 kilowatts.

5. Data available ort the other 3 sites are quite limited. They are summarized in table 1, together with similar data for Blue Mesa Dam. Table 1-'."'Pertinent Enqi,neering Data, Cur.e,canti Unit. , Crest Installed Height of dam length generating Type of above streambed of dam capacity Dam §tructure . (feet) (feet) . -~


Taple 2~-0perating levelsL Curecanti Reservoix Surface Elevation Content area Waj:e_r surf ace (feet) (acre-feet) (acres) Extreme high pool 7~516 17 940,000 9,240 Average annual maximum pool 7,509 876,000 8,970 Average annual minimum pool 7,462 516,000 6,490 · Extreme low pool 7,398 213,000 2,990 Dead storage pool 7,393 200,000 2,850 Sir~ambed 7 183 8. Releases from Curecanti Reservoir and minor inflows from local tributaries will be regulated largely on a daily basis at the Narrow Gauge Reservoir. Water from the reservoir will be released for power production at the Narrow Gauge Powerplant at Narrow Gauge Dam. 9. T~ilwater from the Narrow Gauge Powerplant and a moderate amount of total tributary inflow will be controlled by the . The reservoir will provide regulation largely on a daily and seasonal basis. Release s from the reservoir will be made for power production at the Morrow Point Powerplant, located at Morrow Point Dam. 10. Tailwater from the Morrow Point Powerplant will be regulated on a daily basis at Crystal Reservoir. Releases from Crystal Reser­ voir will be made on a relatively uniform basis, particularly during the irrigation season, · and will be utilized for power production at the Crystal Powerplant, located at Crystal Dam. Releases from Crys­ tal Reservoir will be maintained at rates in excess of diversions to the Uncompahgre project and other presently irrigated lands downstream. 11, A comparison of streamflow on a monthly basis as it would be with the unit in operation as it existed histotically is shown in table 3. In the absence of information concerning rate or frequency of daily streamflow fluctuations with the unit, only the apparent gross effects may be noted. These will be a reduction in volume of high flows and a corresponding increase in volume at times of histori­ cal low flow. Monthly data do not provide the information necessary for adequate analysis and firm conclusions as to conditions with the unit as compared to those without. Modification of streamflow, how­ ever, will have considerable effect upon Gunnison River as far down­ stream as the mouth of N0 rth Fork, and this will be considered the lower limit of project influence.

lT- This extrme {s4' lower than the allowable maximum 7,s·20 ..


Table 3--Streamflow data, Gunnison River below East Portal Gunnison Tunnel Mean monthly discharge (second-feet) 1/ Averaqe Maximum Minimum Histor- With Histor- With Histor- With Month ical* unit ical unit ical un_it October 308 863 1,155 1,157- 33 650 November 473 1,180 874 1,314 118 866 December 379 1,211 504 1,301 293 1,120 January 356 1,222 455 1,301 293 1,122 February 406 1,353 504 1,458 348 1,234 March 523 1,209 878 1,333 309 1,033 April 1,349 903 2,975 1,409 218 580 May 3,806 989 . 6,426 1,762 602 487 June 4;419 2,127 8~134 5,664 202 421 July 1,140 811 2~505 2,068 49 220 August 457 465 1~301 1,036 49 185 September 300 639 1,008 874 34 366 Annual extremes 8,134 5,664 33 185 1./ Prior to October 1937; adjusted to reflect normaloperation of Taylor Park Reservoir, which became operative at the beginning of that month. *Based on Bureau of Reclamation estimate, water years 1931-1944 inclusive. 12. Narrow Gauge and Crystal Reservoirs will each have an active capacity of only 1,000 acre-feet and their overall vertical fluctua­ tion will be nominal. However, since the active capacity of Morrow Point Reservoir will be 42,000 acre feet, annual fluctuations of water level may be as much as 52 feet.

DESCRIPTION OF THE WATERSHED Physical Features 13. The Gunnison River is formed by the confluence of the East and Taylor Rivers at Almont, Gunnison County, Colorado, and follows a 150-mile course to its confluence with the Colorado River at Grand Junction, Colorado. It has a drainage area of approximately 8,020 square miles, of which 3,500 square miles are upstream from the Blue Mesa Dam site. Principal tributaries, located in relation to Blue Mesa Dam site, include Uncompahgre River, 66 miles downstream; North Fork of the Gunnison, 48 miles downstream; Cimarron Creek, 13 miles downstream; Lake Fork of the Gunnison, 1.5 miles upstream; Cebolla Creek, 9 miles upstream; and Tomichi Creek, 27 miles upstream.


14. The Gunnison River watershed upstream from the North Fork confluence -- the area with which this report is primarily concerned is bounded on three sides by l ofty mountain ranges: the West Elk and Elk Mountains to the north, the Sawatch Range on the east, and the Cochetopa Hills, the La Gari ta Mountains, and the San Juan Mountains on the south. The western extremity of the area is marked by broad, high mesas extendi ng southward from the West Elk Mountains and north­ ward from the San Juans. Through these mesas the Gunnison River has carved a precipitously walled gorge approximately 47 miles in length, known as the Black Canyon of the Gunnison. Beginning about 19 miles downstream from the Blue Mesa Dam site, a 13 mile segment of the Black Canyon is of such spectacular depth that it has been proclaimed the Black Canyon of the Gunnison National Monument. Upstream from the Black Canyon the topography is broken by spurs of the surrounding mountains which, in places, extend to the Gunnison River, and else­ where deteriorqte into low ridges or disappear entirely at some dis­ tance from the stream. Throughout the initial 39 miles of its course, the Gunnison River traverses an alternation of shallow canyons and broad, nearly l evel bottom lands. The most extensive of the flats is continuous from near Almont a lmost to the upper limit of the Curecanti Reservoir site. Another prominent flat , the fishing-famous Iola Mead­ ows, lies within the r eservoir site. Elevations in the upper Gunnison River watershed range from approximately 5,280 feet at the North Fork confluence to 14,259-foot Castle Peak in the Elk Mountains. 15. Climatic conditions throughout the Gunnison River watershed, particularly precipitation and snowfall, vary widely according to elevation. At Delta (elevation 5115), near the North Fork confluence, average annual precipitation is slightly more than 8 inches and aver­ age annual snowfall less than 20 inches. At Gunnison (elevation 7683), centrally located in the upper watershed, annual precipitation aver­ ages about 10 inches, ranging from l ess than 7 inches to about 15 inches. Average annual snowfall is nearly 50 inches. At Crested Butte (elevation 8867), in the East River drainage, annual precipita­ tion averages about 22 inches and annual snowfall almost 170 inches. The mean temperature in January, the coldest month, is 12.6°F. at Crested Butte. In July, the warmest month, mean temgeratures at Delta, Gunnison, and Crested Butte are 73.9°F., 61.5 F., and 56.9°F., respectively. The average duration of the growing season is 147 days at Delta, 71 days at Gunnison, and 51 days at Crested Butte. 16. Associated with variation in climate is an equally marked variation in vegetative cover. Tree growth, generally speaking, is restricted to e l evations less than 11, 500 feet. At higher elevations sedges and grasses constitute the dominant vegetation, with dwarfed junipers occupying most or somewhat protected sites. Terrain· between 8,000 feet and 11, 500 feet in elevation is, for the most part, densely forested, but grasslands frequently occupy the more level sites, par­ ticularly those adjacent to watercourses . Engelmann spruce, lodgepole

5 BUREAU OF SPORT FISHERIES AND WILDLIFE pine , and alpine fir are the predominant coniferous species, but lim­ ber pine , bristlecone pine, blue spruce, and Douglas-fir also are repre sented. Aspen is by far the most abundant broadleafed tree. Below 8,000 feet, tree growth consists largely of open stands of pinon pine , Rocky Mount ain r ed cedar, and one-seed juniper; however, Douglas-fir, aspen, and even Engelmann spruce persist on north-facing slopes and in deep canyons, and narrowleaf cottonwood, lanceleaf cot­ tonwood, and blue spruce a r e found near watercourses . The pinon pine ­ cedar-junipe r stands gene rally display an understory of mountain mahogany, skunkbush, serviceberry , and bitterbrush, and they frequently give way entire ly to a brushland type comprised of one or more of those speci es, or to dense thickets of oakbrush. At the l ower e l eva­ tions, rolling t e rrain usually is dominated by sagebrush. Flats ad­ jacent to the Gunnison Rive r and the l owe r reaches of its tributaries consist largely of grassland, most of which is irrigated and mowed for hay. Irrespective of elevation, water course s are fringed by willows. Alder is also common along str earnbanks at e l evations up to 9,000 feet. 17. Flows of the Gunnison Rive r are partly r egulated by Taylor Park Reservoir, a Bureau of Reclamation development near the head­ wate rs of the Taylor River. Upstream from Blue Mesa Darn site the Gunnison Rive r and virtua lly a ll of its tributaries furnish wate r for irrigation of nearby meadows, but t he volume consumed is not suffi­ ciently great that the f l ow of the main stream i s reduced in signifi­ cant degree. Nineteen miles downstr eam f r om the Blue Mesa Darn sit e , however, is a diver sion which, from Apr tl through November, oft en severely depletes str earnflow . This i s the Gunnison Tunnel, constructed in connection with the Bureau of Reclamation' s Uncornpahgre project, through which waters of the Gunnison River are transported t o irrigate lands in the Uncornpahgre River Va lley. At the Blue Mesa Darn site, the ave r age flow of the Gunnison River amounts to 1, 337 second-feet; the maximum monthly mean discharge, 4, 238 second-feet, occurs in June ; and the minimum monthly mean discharge, 327 second-feet, occurs in February. Below the Gunnison Tunnel the average flow is 1,160 second­ f eet , and the mean discharge for June, again the high month, is 4,419 second-feet; September i s the month of minimum mean discharge, 300 second-feet. The severity of the Gunnison Tunnel diversions is exern· plified, howeve rt by comparison of minimum mean monthl y di scharges f or June and September immediately upstream and downstr eam from the dive r­ sion sit e : in June , dive rsions have r educed the mini mum mean monthly discharge from 1 , 210 second- feet to 202 se cond-feet, and i n September, from 689 second -feet to 34 second - feet . Hydrologica l data pertaining to the Gunnison River and to those tributaries which would be affected by Curecanti Reservoir or a r e otherwise significant to this report are summarized in table 4.

6 Table 4 - Historic Streamflow Data, Gur.nison River and Tributary Streams Gunnison River Gunnison River Gunnison River Gunnison River at Blue Mesa above Gunnison below Gunnison at Iola Dam Site Tunnel Intake Tunnel Intake Source of data U. S.G.S. 1/ U.S.B.R. 2/ U.S.B.R. 2/ U.S.B.R. 2/ Period of record - water y-ea_r_s-----=-13:-'-y_e_ar_s _____-=1"""5-y-ears -~ years 14 years____ _ ~~~~~~~~~~~~(~19~3_8_-1~9-51~)~~~(1~9~31~-1945) (1931-1944) (1930-1944) l~onthly Mean Discharge in Second-Feet October 418 600 683 308 November 364 507 580 473 December 290 375 384 379 January 255 332 356 356 February 235 327 406 406 ~1arch 308 466 573 523 April 942 1,450 1,858 1,343 May 2,187 3,637 4,434 3,806 June 2,842 4,238 5,081 4,419 July 1,245 1,846 2,052 1,140 August 910 1,287 1,383 457 September 706 950 1,052 300 Maximum mean monthly discharge (second-feet) 4,208 7,109 8,621 8,134 Minimum mean monthly discharge (second-feet) 169 261 293 33 Average discharge for period (second-feet) 893 1,337 1,572 1,160 1/ U:-S-.-Ge-.:.o-1.o_g_i_· c-a-1- Su_r_v_e_y_ "'i_l U. S. Bureau of Reclamation Sheet 1 of 2 sheets Table 4 - Historic Streamflow Dataz Gunnison Ri~nd Tributary Streams (Continued) Cebolla Creek Lake Fork Cimarron Creek North Fork at Gunnison River at Gunnison River Powderhorn at Gateview Cimarron near Somerset Source of data-- u.s.a.s. 1/ u.s.a.s. 3/ u.s.a.s. 1/ u.s.a.s. 1/ 12 years 2/ 11 years 3/ 9 years -15 years Period of record - Water Years · ( 19 39-l952) (1939-1952) (1943-1952) ( 1937-1952) --- -- Monthly Mean Discharge in Second-Feet I 101 111 ~ October 63 33 0 November 50 64 37 89 '"rj December 46 55 37 72 en January 42 47 31 67 ~ February 41 43 31 71 1-3 41 114 '"rj March 47 50 H April 115 161 145 844 en co May 304 599 365 2,200 ~ June 278 1,131 537 1,535 ~ July 118 563 132 404 en August 100 213 41 147 :x> September 69 130 28 103 § Maximum mean monthly discharge s (second-feet) 626 1,568 827 2,984 Minimum mean monthly discharge (second-feet) 30 35 15 46 ; Average discharge for period (second-feet) 107 264 122 481 -vu:-s. Geological Survey 2/ 1943-1944 water year omitted "J./ 1942-1943 and 1943-1944 omitted Sheet 2 of 2 sheets BUREAU OF SPORT FISHERIES AND WILDLIFE

Commercial Features 18. In the upper Gunnison River watershed, the economic struc­ ture is based in large and almost equal measure upon two activities: (1) livestock raising and (2) providing goods and services to outdoor recreationists. Mining, once a thriving industry, and lumbering, which has yet to attain its full potential, are currently of secondary im­ portance. 19. The 1950 census recorded a population of 2,729 for Gunnison, the largest town in the upper Gunnison River watershed. Crested Butte, Pitkin, and Lake City, the only other incorporated towns, had popula­ tions of 729, 152, and 132 respectively. The four towns represent more than half of the total population of the area. Two small commun­ ities, Iola and Sapinero, lie within the Curecanti Reservoir site. 20. U.S. Highway 50, a major transcontinental route, parallels the Gunnison River and Gunnison to Sapinero, passing through the Cure­ canti Reservoir site. State Highway 161 follows the Lake Fork of the Gunnison from near Sapinero past the upper limit of the reservoir site. Between Sapinero and the Cimarron Creek confluence, in the upper reaches of the Black Canyon, the Gunnison River is flanked by an aban­ doned roadbed of the Denver and Rio Grande Western Railroad which the Colorado Game and Fish Department has developed as an automobile road to provide access for fishermen. State Highway 135 follows the Gunni­ son River upstream from Gunnison to Almont. Other State highways, and county or Forest Service maintained secondary roads, radiate from U. S. Highway 50 into outlying portions of the upper Gunnison River water­ shed. The area is no longer served by a railroad, but Gunnison is a scheduled stop for one bus line and one air line. 21. Despite the existing transportation facilities, many parts of the upper Gunnison River watershed are not easily accessible. Notable among these are the Black Canyon downstream from the Cimarron Creek confluence and the segment of Cebolla Creek within the Curecanti Reservoir site. FISHERY SECTION

Without the Proiect Extent and quality of habitat Gunnison River 22. North Beaver Creek to Black Canyon.--The 22.5 miles of Gun­ nison River in this reach are unsurpassed in quality elsewhere in


Colorado. There is an average gradient of 20 feet per mile. Rubble and gravel are the predominant components of the streambed. Although typical pools are not munerous and the stream may appear to be almost a continuous deep riffle, there are long reaches of deep, fast, but not turbulent water bordering the riffles. This deep water takes the place of pools, providing concealment and resting places for trout adjacent to the food-producing riffles--an ideal situation from the standpoint of maximum carrying capacity, and trout growth. Aquatic insects provide an abundant food supply. Overhanging branches of shrubs and small trees furnish cooling shade and concealment near the streambanks. Spawning facilities are of top quality, with those in the river being supplemented by those in numerous tributaries. The recognized quality of the fishery is evidence that present water tem­ peratures and water quality, as well as the other factors mentioned, are highly satisfactory for trout. · 23. Black Canyon.--From Blue Mesa Dam site near the head of Black Canyon, the Gunnison River i s confined in a gorge for most of the 48 miles before it r eaches the mouth of North Fork. Although the habitat is undoubtedly affected somewhat by curtailment of flow below the east portal of Uncompahgre Tunnel, it is essentially the same quality throughout. The gradient is about 40 feet per mile and the stream flows through a series of deep pools interrupted by boulder­ strewn rapids. The streambed averages only about 100 feet wide as compared with an average width of 250 feet in the valley above Black Canyon. Pools are excellent but production of trout food organisms is limited by scarcity of good riffle areas. Few trees grow along the stream's edge in the bottom of the canyon, although there is a scatter­ ing of shrubs and herbaceous plants. Water quality and temperatures are comparable to those in the reaches upstream. Although not as good as the reach from North Beaver Creek to Black Canyon, the Gunnison River in Black Canyon is still excellent trout stream habitat. Major Tributaries 24. Lake Fork of Gunnison River.--Sloping northward toward Gun­ nison River at the rate of 41 feet per mile , the bed of the Lake Fork lies in a deep, narrow canyon. Although there is little streambank vegetation except for widely separated clumps of trees or brush, the canyon walls provide shade throughout a large part of the day. The stream is clear except during periods of exceptionally high runoff and occasionally at other times when mine-tailings t emporarily cloud the waters. Tailing pollution has not been a serious detriment to the quality of habitat as is evident from the abundance of trout food or­ ganisms. In other r espects, habitat factors are excellent. The stream bottom is composed of small boulders, rubble, and gravel. Pools are deep and well balanced by equal areas of productive riffles. 25. Cebolla Creek.--Winter flows in Cebolla Creek are comparable in size to those in Lake Fork, although summer flows average about 1/3

10 BUREAU OF SPORT FISHERIES AND WILDLIFE as great. Cebolla Creek Canyon is not as deep or as narrow as that of Lake Fork and, consequently, the r e is more opportunity for growth of trees and shrubs on the canyon floor. They densely border and over­ hang the stream channel. Similar in other r espects to Lake Fork, but without any pollution from tailings, Cebolla Creek provides highly productive trout habitat.· Minor Tributaries 26 . Red, We st Elk, East Elk, No rth Willow, and South Willow Creeks have insufficient flow in dry years to maintain permanent fish populations, although other habitat fact ors a r e satisfactory. In West Elk, East Elk, and North Wi llow Creeks, the deficiency is caused by diver sion for irriga tion. These streams support t rout above the points of diversion. In spring ther e is sufficient flow so that spring spawn­ ing spe cie s migrate from Gunnison River into East El k and North Willow to r eproduce and West Elk, Red, and Sout h Willow Cr eeks may be utilized also. 27 . Soap, Steuben, and North Beaver Creeks are permanent streams populated by trout throughout the year and serving as spawning grounds f or trout from Gunnison River. · 28. Streams e nte ring Gunnison River within Black Canyon include Pine, Blue , Curecanti , Cimarron, and Crystal Creeks . With the excep­ tion of Cimarron Cr eek, a ll of t hese streams descehd p recipitously into the canyon and p rovide littie if any habitat. Cimarron Cr eek has a moderate gradient and a good type of bed but suffers f r om lack of water due t o upstream diversions as we ll as a heavy sediment l oad when flows are otherwise satisfactory. Game fish populations 29. Three species of trout--rainbow, Eastern brook, and br own-­ are the principal game fish. Rainbow and brown trouts predominate in the Gunnison Rive r a nd also in t he l ower reaches of Lake Fork and Cebolla Creek . Eastern brook trout predominate in most of the small tributaries having any signi ficant fishery value, except the Soap and North Beaver Creeks , where r ainbows a r e as abundant as brook trout.

30 . Because of the popularity of the Gunnison River wi thin Cure ­ canti Reservoir site, the Co l orado Game and Fish Depar tment suppl ements the natural productivity of the str eam with hatcher y-rear ed trout, most of which a r e rainbows. Br own trout have demonstrated their ability t o maintain a large popul ation i n the str eam despite the fact that they furnish 37 percent of the total harvest. Therefore, t hey have not been stocked since 1953 . A large percentage of the rainbow trout caught are also produced naturally. Without the large resident trout popu­ l ations, coupled with ve r y favorable conditions which e xist for repro­ duction and growth, it woul d be impracticable t o maintain t he high quality fishing which is expected by t hose who fish t he Gunnison Rive r.


Utilization and harvest Field Investigations 31. The 1956 trout season in Colorado extended from May 19 through October 31. An investigation of fishing use and harvest was conducted during the period from June 28 through September 12. Addi­ tional observations indicated that practically all of the fishing use occurred between opening day and September 30. Various sections of the river and associated tributaries were grouped into work units to facilitiate survey by the 3 crews so engaged. A schedule was developed to assure an adequate random sample of use and harvest for each day of the week. Information so gathered was projected to give an estimate of total use and harvest during the season. Gunnison River 32. The most heavily fished reach of Gunnison River in the proj­ ect area is that from North Beaver Creek to Blue Mesa Dam site, that· is, within the limits of Curecanti Reservoir site. Numerous resorts, cabins, and camp sites provide necessary accommodations. This section includes the major portion of the river suitable for float fishing and its utilization in that manner is increasing each year. Fishermen have practically unrestricted access for fishing from the banks or by wading the stream. Posting against bank fishing occurs in only 2 places throughout this reach--approximately 85 percent is open to public ac­ cess. All of these factors plus the reputation of the Gunnison River as one of the nation's most famous and productive trout streams con­ tribute to bringing about a tremendous amount of fishing use. In 1956 this amounted to 37,600 fishing days. Trout harvested numbered 163,300. 33 . From Blue Mesa Dam site, near the head of Black Canyon, to the mouth of North Fork, there is no restriction on access except that imposed by the canyon itself. For the first 13 miles below Blue Mesa Dam site, access has been facilitated by the Colorado Game and Fish Department through converting the abandoned railroad right-of-way into an automobile road. This road ends at Cimarron Creek but it is quite easy for fishermen to use the next 2 miles, which brings us to the Crystal Dam site. Although not as popular as the reach above Blue Mesa Dam site, these 15 miles receive heavy use; they supported 9,700 man­ days of fishing recreation in 1956, with a harvest of 39,300 trout. 34. There is little difference in utilization throughout the reach between Cimarron C~eek, 2 miles upstream from Crystal Dam site, and the east portal of Gunnison Tunnel, 4 miles downstream from it, the choice of breaking point being merely a matter of convenience for later comparison. The road into the tunnel diversion site is steep but can be travelled by automobile. It is the only point of automobile

12 BUREAU OF SPORT FISHERIES AND WILDLIFE access between Cimarron Creek and the mouth of the North Fork. Use of the 4-mile reach above the tunnel portal amounted to 1,200 man-days of fishing in 1956. An estimated 2,500 trout were taken in this reach. 35. Below the tunnel portal, use is limited to those who fish downstream from that point or those who work their way upstream from access points below the deepest portion of Black Canyon. Such use is limited to periods when flows are low enough to permit negotiating the gorge safely. Relatively speaking, the 600 man-days of fishing use and the 1,300 trout harvested in the 29-mile reach below the portal are of little importance. 36. In all, the Gunnison River from North Beaver Creek to the mouth of North Fork, a distance of approximately 70 miles, sustained a use of 49,100 man-days for fishing in 1956, with a yield of 206,400 trout to the creel. Roughly four-fifths of this use occurred in the initial 22.5 miles (within Curecanti Reservoir site), while most of the other one-fifth was in the 15 miles from Blue Mesa to Crystal Dam site. Considering the sharp upward trend in our human population growth, the increasing numbers of people who fish, the trend toward · more leisure time, and the continuing loss of other str eam fisheries, it is estimated that annual use of the Gunnison River over the next 50 years will average 73 ,600 man-days of fishing and will furnish an annual harvest of 309,600 trout. Tributaries 37. Although in a deep canyon, a passable road extending along the Lake Fork provides access . The 1956 fishery investigations on the reach within Curecanti Reservoir site showed that use amounted to 3,400 man-days of fishing, with a resulting harvest of 22 , 000 trout. Use on other tributaries was so small that no estimate for total seasonal use and harvest was attempted. In projecting average use over the next 50 years, only Lake Fork was consider ed as having enough importance to warrant an estimate . For the Lake Fork, average· annual fishing use and harvest will amount to 5,100 fishing days and 33 ,000 trout, respectively.

With the Proiect Eff~ct on stream fishery Loss by Inundation 38. Curecanti Reservoir will eliminate the stream fishery value of 22.5 miles of the most productive part of Gunnison River through permanent or periodic inundation. Immediately downstream, Narrow Gauge, Morrow Point, and Crystal Reservoirs will flood out 15 more miles of choice trout fishery. In addition to Gunnison River itself, 8 miles of Lake Fork and 16 miles of other tributaries including North Beaver,


Steuben, East Elk, West Elk, Soap, and Cebolla Creeks will be inundated together with an insignificant mileage of 4 other small tributaries. Modification of Streamflow 39. Curecanti unit will regulate flows of Gunnison River below Crystal Dam. Indications are that high flows will be reduced, while normally low flows during the winter months will be increased as much as 3 times the historical amounts. This will not be detrimental to the habitat. The considerably larger flows indicated for August and Sep­ tember will make it more difficult and dangerous to fish the canyon up through the National Monument, but the relatively small use of the river downstream from Gunnison Tunnel makes this a matter of little concern. In the 4 miles between Gunnison Tunnel and Crystal Dam, ac­ cess will doubtless be improved, fish will tend to concentrate below the dam, and fishing use will increase. A complete cessation of flow from Crystal Dam would be extremely detrimental, but until further de­ velopments (particularly trans-basin diversions) occur upstream, it does not appear that releases from Crystal Dam would ever need to·be completely shut off. Fishing use with the project will average 2,700 man-days, the bulk of which will occur on the 4 miles immediately below Crystal Dam. Annual harvest will amount to 5,700 trout. Both utili­ zation and harvest are based upon the assumption that adequate minimum flows will be provided. Reservoir fishery Extent and Ouality of Habitat 40. Curecanti Lake will have 6,490 acres of water surface at average annual minimum pool elevation. Water levels will rise during spring and early summer, reaching their maximum for the year early in July, after which reservoir content will decline until it reaches the minimum the following March or April. Annual vertical fluctuation will average 47 feet. 41. As the waters gradually inundate the bottom lands for the first time, accumulated nutrients in the soil and the flooded vegeta­ tion will create a highly productive habitate from the standpoint of fish growth. After 2-3 years, certain factors inherent in reservoir lakes will have reduced habitat quality to the characteristic low point. The large exchange of water in the lake each year will rapidly deplete fertility. Vertical fluctuations will prevent the establish­ ment of rooted aquatic vegetation along the shorelines, which otherwise might contribute satisfactory feeding habitat. Wave action, coupled with vertical fluctuation, will work and rework sediments in the ever­ changing littoral zone, creating conditions unfavorable to growth of bottom organisms which would otherwise be an important source of trout food. Former spawning grounds for trout will largely be lost through inundation, while spawning conditions for rough fish, primarily suck­ ers, will be improved.


42. The total surface area of Narrow Gauge, Morrow Point, and Crystal Lakes will be 1,200 acres at maximum pool levels. Seasonal fluctuations of water levels in Narrow Gauge and Crystal Reservoirs will be small, although daily fluctuations due to power releases will occur. Fluctuation in Morrow Point Reservoir will be even more severe than in Curecanti, with a possible maximum of 52 feet. 43. The quality of habitat in these three reservoirs will be lower than in Curecanti. The rugged topography of Black Canyon will permit development of no real littoral zone which is an important fac­ tor in lake productivity. Neither the reservoirs nor the generally precipitous inlet streams will provide any significant spawning area. Cimarron Creek has a relatively gentle gradient, but other factors limit it to little or no value for spawning. Fish Populations 44. With substantial improvement in habitat so far as they are concerned and with a reproductive potential 10-15 times as great as trout, suckers will soon be nume rically dominant in Curecanti Lake. Although trout will still have available the spawning grounds afford­ ed by the several tributary streams, natural reproduction alone will not be sufficient to maintain in a body of water of this size a trout population large enough to furnish attractive sport for fishermen. The rate of catch per man-hour will be low. It is very likely that it will remain low even though the native population is augmented by large numbers of hatchery-reared trout. Kokanee salmon will probably be introduced, since theoretically they are better adapted to these fluctuating lakes than are trout. They will spawn in the lake under certain favorable conditions, they are plankton feeders, and they pre­ fer deep waters for resting. They might build up a large population, although information from other Colorado waters does not prove con­ clusively that they can be counted upon to do so. 45. In view of the unproductive quality of the other unit reser­ voirs,together with the fact that access to them will be difficult and that reservoir lake fishery needs, such as they are, will continue to be met by Taylor Park Lake, augmented by Curecanti Lake, it is doubtful that any intensive fishery-management program will be war­ ranted. Fish populations in these three lakes will be low. Utilization and Harvest · 46. During the initial period of high fertility, abundance· of food, and consequent rapid growth of game fish in Curecanti Lake, it will attract fishermen from all over the State of Colorado, as well as from other states. Use will inevitably decline as the fishery becomes less attractive. Based upon data from existing impounded trout waters in Colorado, a success ratio of .25 game fish per man-hour or four hours fishing effort to catch one fish will be the best that can be expected from Curecanti Lake over a fity-year period. Still fishing

15 BUREAU OF SPORT FISHERIES AND WI~DLIFE from shores or from boats or trolling with "hardware" from power boats will be the most effective methods of fishing. Suckers will become a nuisance to the still-fishermen. Annual fishing use of Curecanti· Lake will ave rage 17,300 man-days and annual harvest will amount to 22,400 fish during the initial 50 years. Annual fishing use of the 3 down­ stream r e servoirs will amount to only 1,500 man-days, collectively, with an annual harve st of 500 fish. Summary-- Fishery Resources 47. The 4 dams in the Curecanti unit will create lakes which at average annual minimum pool capacity· will have a collective water sur­ face of 7,490 acres . Of this amount, Curecanti accounts for 6,490 acres. In creating these l akes, the unit will flood out 37.5 miles of Gunnison River, 8 miles of Lake Fork, and 16 miles· of other tribu­ taries. With the exception of some minor tributaries, these streams are high quality trout habitat. The present success ratio for the Gunnison River is over 2.5 time s the estimated catch per man-hour which can be anticipated from the r eservoirs. A detailed breakdown of the habitat, fishing use , and harvest as it will be affected by the proj­ ect is pre sented in table 5. WILDLIFE SECTION Without the Project General Statem~nt Spe cies Present 48. The only important game animal in the project area is mule deer, although elk are pre sent in the adjacent mountains and occa­ sionally spend a brief time on the Curecanti Reservoir site. Other wildlife species found in the ·area include sage hen, cottontails, Rocky Mountain bighorn sheep, mourning doves, several species of ducks, beavers, muskrats, and minks. Vegetative Cover Types 49. The three downstream r eservoir sites--Narrow Gauge, Morrow Point, and Crystal-- are located in the deep, rocky canyon of the Gun­ nison River, with f ew breaks in the steep canyon walls. The tribu­ taries entering the Gunnison in this r each are similar except for the Cimarron Creek watershed which is l e ss precipitous and contains some unimproved pasture. These smalle r reservoir sites were not cover mapped because of their minor wildlife value . 50. Table 6 presents the acreage and pe rcent of cover types within the average annual maximum pool of Curecanti Reservoir.

16 ____T_a~_5'-----S_W'lll_m_ar__,y ___ o_f_F_is_h_H_a_b_i_t_at_,,.__u_t_i_li_·._z_at_i_· o_n'""',_an_d_H_a_r_v_e_s_t_v_n_ · t_h_o_u_t_an_d_wi_·_t_h_t,h__ e_Pr_o __ j_e_c...,t Without the Project Wi th the Project Difference · Extent Use in~~ Extent Use in Number Extent--iTs'e of Number of Han- of Fish of Man- of Fish of Man- of Fish ~~~~~~·~~----H_a_b_i_t_a_t __d_ a_y_s~_H,ar__ v_e_s __ ted Habitat days Harvested Habita~ays Harvested Gunnison River within Curecanti site 22 .5* 56,4CD 244,900 -22.5* -56,400 -244,900 Three lower sites 15. 0* 14,600 59,000 -15. 0* -14, 000 - 59, 000 Gunnison (Cr ystal Dam to North Fork confluence) 33 . 0-::- 2, 7CX) 5, 700 33.0-i, 2, 700 5,700 Lake Fork 8. 0-:~ S,100 33, 000 8.0* - 5, 100 - 33,000 Other tributaries 16. 0-l~ -16. o-i~ Curecanti Reser voir 6, 490. -lf-* 17, 100 22,400 6,490·::"* 17,300 22,400 Narrow Gauge, Morrow Point, Crystal Rese~ - ~--~1_1,;_0_0_0~ l -/ ~_l_._S__O _O~~----soo ..b..00~- 1,soo 500 TOTAIS 94.S* 78,800 342,600 33 . 0,} 21,5CO 28,600 61.5* -57,300 -314, COO 7 , 490-iH:- ---7, 490-::->,; · * - Mil es iH:- - Acr es y - Assumed average annual minimum water surface BUREAU OF SPORT F ISHER.IES AND WILDLIFE

Tabl~~ 6_:_::_Cover types on Curepgnj:LR~servoir Site Average annual maximum pool Cover type Acreage Percent Highland brush (BH) 4,700 52.4 Lowland brush (BS) 331 3."7 Grassland, pasture (GI) 188 2.1 Grassland, hay (G2) 1,890 21.1 Broadleaf trees (D2) 541 6.0 Evergreen trees (C2) 566 6.3 Water (WA) 481 5. 4 Miscellaneous 273 3.0 8 970 100.0 51. }lighland brush is found back on the side slopes of the Gunni­ son River Valley and tributary valleys and on the flat mesas lying be­ tween the tributary streams. It is composed primarily of sagebrush interspersed with patches of · mountain mahogany, serviceberry, bitter­ brush, oakbrush, rabbitbrush, and skunkbush. Lowland brush, chiefly willow and alder, borders the streams in the area. The flat bottom lands of the Gunnison River and its larger tributaries are irrigated and planted to hay. The rolling portions of the bottom lands are de­ voted to pasture. Cottonwoods and willows along the streamcourses and pockets of aspen, above the average annual maximum pool level, are pri­ mary components of the broadleaf tree group. The evergreen trees are chiefly Douglas-fir and spruce occurring on north-facing exposures. Mule deer Extent and Quality of Habitat 52. The quantity and quality of deer wintering range is gener­ ally critical in Gunnison County where major losses of deer have oqcur­ red when heavy snow covered the area· for extended periods. In 1942 and 1943 a combined total of over 11,000 winter-killed deer were actually counted by Colorado Game and Fish Department personnel; many within the reservoir limits. 53. There are 6,140 acres of fair to poor quality mule deer wintering range within the average annual minimum pool of Curecanti Reservoir site with an estimated carrying capacity during the winter period of about one deer per 15 acres. Present and Future Status of Population 54. Studies of the Gunnison deer range made in 1939-1940 by the Colorado Game and Fish Department in cooperation with the U.S. Forest Service showed the carrying capacity of this range to be one deer per 12 acres during the winter period. These studies were made at a time

18 BUREAU OF SPORT FISHERIES AND WILDLIFE when the carrying capacity of the range had already deteriorated some­ what since overutilization has already occurred. Hence it is deducted that with good management and resulting range improvement one deer per 10 acres during the winter can be sustained over a long period of time. Thus the average winter population of mule deer in the Curecanti Re­ servoir site is estimated at 614 annually during the life of the proj­ ect. 55. The present population of mule deer wintering in the Cure­ canti Reservoir site is approximately 1,000 animals or an average den­ sity of approximately one deer per six acres . The present population density is about 40 percent greater than the estimated long term car­ rying capacity of the range. Utilization and Harvest 56. Studies of the Piceance--White River deer herd in Colorado indicate that a 35 percent annual harvest of the base herd will hold the population density of the herd at the existing level. Assuming then a 35 percent harvest of the base herd wintering on the Curecanti Reservoir site, 215 mule deer would be harvested annually. Other studies made by the Colorado Game and Fish Department in Gunnison County indicate that these 215 deer will provide 1,870 man-days hunt­ ing recreation for 480 hunters. Elk 57. There are only about 350 acres of habitat suitable for win­ tering elk to be affected by the project. The number of elk using this area is insignificant. Rarely, once in ten years or more, a large number of elk move down into the Curecanti Reservoir site dur­ ing severe winters where they feed primarily on haystacks and conse­ quently become a nuisance. These forage forays into the project area are usually of short duration. The utilization of this area by elk is quite small when averaged over a long period of time and, therefore, is considered insignificant. Bighorn sheep 58. A small hered of bighorn sheep, estimated at 21 animals in 1950, has long been resident in the Black Canyon of the Gunnison · National Monument . They occasionally range up the river towards Cimar­ ron, but very seldom into the area of the three smaller impoundments of this project. No hunting is permitted in the Gunnison National Monument. Sage hen 59 . The Curecanti Reservoir site contains 8,200 acres of fair to good quality sage hen habitat. These birds spend most of the summer in

19 BUREAU OF SPORT FISHERIES AND WILDLIFE the meadows, haylands, and pasturelands. They winter on the rolling highland-brush type habitat. 60. ~n average annual population of 1,100 sage hens is estimated for the Curecanti Reservoir site. Sage hen populations have been in­ creasing during the last several years in this area. In fact, · popula­ tions have built up to where a hunting season has been opened for this species since 1953. The Gunnison River Valley above Sapinero is one of the better sage hen hunting areas in the State. It is estimated that there will be about 190 man-days of hunting and 275 sage hens harvested annually in the Curecanti Reservoir site. Cottontail 61. There are 8,200 acres of good quality cottontail habitat in the Curecanti Reservoir site. Brush-covered draws and river bottom­ land coverts are the favored habitat of this species. Although cot­ tontail populations are subject t o pe riodic fluctuations, it is esti­ mated that the average population will be 5,250 animals annually. Cottontail hunting is becoming increasingly popular with local hunt­ ers. It is estimated that throughout the life of the project there will be 260 man-days of hunting and 1,050 cottontails harvested on the project area each year. Mourning dove 62. Dove habitat within the Curecanti Reservoir site is esti­ mated at 3,000 acres. Groves of trees in association with bottom-land crops are important components of the habitat of this species. An estimated 295 pairs of doves raise broods in the area each year. Dur­ ing the months of May through September it is estimated that there will be an average utilization of 160,000 dove-days annually. Dove hunting is negligible in the project area. Waterfowl 63. Duck habitat within the Curecanti Reservoir site consists of 485 acres of streams and ditches and 190 acres of overflow lands. These areas in association with hay meadows provide limited nesting habitat for ducks, particularly mallards. There is little use of the Gunnison River by migrant wate rfowl and only minor use by a few sum­ mer residents. Total waterfowl utilization is estimated at 223,800 duck-days annually. Duck hunting is poor because most of the summer­ resident birds leave before or shortly after the Colorado waterfowl season begins and because few waterfowl stop in the area during fall migration. The amounts of wate rfowl hunting and waterfowl harvested are insignificant. Fur animals 64. Beavers, minks, muskrats, skunks, weasels, foxes, and coyotes

20 BUREAU OF SPORT FISHERIES AND WILDLIFE are found on the project area. Of these only beavers, minks, and musk­ rats are of significant corrunercial value.

65. Beaver trapping is prohibited in Gunnison County at present (except in cases where they constitute a nuisance) but it is assumed that open seasonson these species will be declared in the future due to population increase s. It is e stimated that there will be an annual harvest of 47 beavers, 125 muskrats, and 25 mink within the Curecanti Reservoir site. With the Proiect Mule deer 66. The 6,140 acres of winter mule deer range below the average annual minimum pool of Curecanti Reservoir will be permanently lost and the area above this pool level up to the maximum reservoir pool level will contain little winter browse because of periodic flooding. That portion of the western Gunnison County deer herd dependent upon this winter range and its production of fawns will be lost. Elk 67. The 350 acres of true elk winter habitat lost through the project will have little or no eff ect on elk population densities or elk hunting in Gunnison County. Loss of other land area in the Cure­ canti Reservoir site that is not strictly elk habitat but is used on rare occasions by this species will also have no important effect on populations or hunting in the vicinity. Bighorn sheep 68. The herd of bighorn sheep resident in the Black Canyon of the Gunnison National Monument will suffer no significant loss of either range or numbers when Crystal, Narrow Gauge, and Morrow Point Reservoirs are filled. Sage hen 69. Inundation of meadows, pasturelands, and haylands along the Gunnison Valley as well as sagebrush habitat on the lower benchlands will spell the doom of sage hen hunting in the Curecanti Reservoir area. The loss of this habitat will mean the loss of a major part of the nest­ ing grounds, winte ring areas, and strutting grounds without which this species will not be able to produce a harvestable surplus. Cottontail 70. Cottontails and cottontail hunting will also be eliminated from the are a below the average annual maximum pool of the reservoir. The few animals remaining on suitable habitat above this pool level

21 BUREAU OF SPORT FISHERIES AND WILDLIFE will be too few to attract a significant amount of rabbit hunting. Waterfowl 71. Flooding Curecanti Reservoir site will not result in import­ ant l osses to wate rfowl, although it will destroy most of the ne sting habitat used by a f ew ducks t o bring off b roods in this area. A small arm of Cimarron Creek will provide a little nesting habitat but its value will be negligibl e. Resting habitat in the reservoir will be of little value to the few migrating wate rfowl passing through this area because of its poor quality and the lack of waterfowl food plants avail ­ able . Inundation of croplands will also e liminate this source of water­ fowl f ood . Average utilization of the proje ct area by wate rfowl is e stimated at 67,050 duck-days annually. 72. It is e stimated that the Curecanti area will provide about 50 man-days of wa~rfowl hunting and a harve st of 50 waterfowl annually . Fur anima l s 73. Fur-animal populations associated with an aquatic habitat (beaver s , minks, and muskrats) will be reduced when favored habitat is inundated by a fluctuating l ake with a barren shoreline. Te rrestrial fur animal s will be forced to leave the r eservoir sit e . 74. As a result fur-animal harve sts will be r educed to 10 beavers, 12 mu skrats, and 12 minks annually. Summary of Conditions Without and With the Project 75. Construction of the Blue Mesa Dam will cause the inundation of about 6, 140 acres of mule deer habitat necessary to the maintenance of about one-t enth of the western Gunnison County deer herd. It will also r esult in the inundation of sage hen and cottontail habitat ne c­ essary to the production of a harve stable surplus of these species. This t e rrestrial habitat will be r epl aced by a poor quality aquatic habitat capabl e of supporting a few wate r fowl and fur animals. 76. Flooding of the Cur ecanti Reservoir s ite will destroy habi­ tat that provided over 2, 300 man-days of big-game and upland-game hunt­ ing annually and a harvest of over 1, 500 animals . Curecanti Lake will create habitat providing 50 man-days of waterfowl hunting and a har­ vest of 50 ducks . 77 . Tabl e 7 presents a summary of wildlife r esources utilization and harvest.

22 Table 7 - Summary of Wildlife Resources, Utilization. and Harvest Without the Project With the Project Difference

s::- s:: s:: s:: 0 !/) s:: o- s:: o- 0 ·r-i :>, 0 •r-i (/) 0 •rl !/) ,,-j +> co ·r-i +' :>, ·r-i +' :>, ...,_ ct! ct! +> ...... ct! C'O !/) +>- +> ro -o +> +> +> +' +> ct! (I) N I (IJ ro (IJ ct! ~ 'O (/) <1l (IJ C'O ts) 'O Cll Cl) Q) +' Cl) ,::1 Cl) +' Cl) r-1 ·r-i Q) +> Cl) r-1 ·r-i .,..; H ;q @ ·r-l H r-1 s:: :> ·ri H ;q ~ C) ..0 (.) ..0 (.) •ri ct! ..0 (.) ·r-i co Cl) a •r-i s a <1l a ro m 0 +> '-" ~ +> s ~ ro :::,+' ...... ,.s ~ Jr ::c:- P-< :::, :;J::l ~~ r£ :::, '-' ::c: ::c:- r£ ::c: Big game Hule deer 6,140 614 1, 868 215 -6,140 - 614 -1,868 215 - 350 ic::: Elk 350 Insig. ------0 Bighorn sheep 21 21 ------',cj Upland game S@ Sage hen 8,200 1,100 190 275 -8,200 -1,100 190 275 Cottontail 8,200 5,250 260 1,050 .,__ -8,200 -5,250 260 -1,050 § r'\) M . d -3,000 -159,300 ',cj w ourning ove 3,ooo 159,300 !I lf ------H (/) Waterfowl ::r:: + Ducks 675!/223,80011 8,970!:,/67,05011 50 so +8,295 -156,750 J/+ so so ~ Fur animals ~ Beavers 70 5/ 188 47 8,970 38 10 ------150 37 C/) 113 :i:a, Muskrats 70 - 250 125 8,970 50 12 1 ------200 ~ 13 t::i ·-}~u~·nk.;.;._~-~~_JQ_·---~--10_0~~~~~~25__.__ 8~t~9~7_0~~---'-o~~~-1_2~ 1--_-_-_-_--~~_iQ_·--~~~~~---~ ~ H 1/ Utilization - dove days 8 2/ Permanent water and periodically flooded land with t:-< average annual maximum pool 3/ Utilization - waterfowl days ~ Ti./ Average annual maximum pool - Cure-canti Reser"oir 2/ Number of miles of Stream Habitat BUREAU OF SPORT FISHERIES AND WILDLIFE


Resources in Relation to Needs Fishing r e creation 78 . The Gunnison Rive r and its tributaries in that portion of the basin upstream from t he mouth of North Fork are highly important in meeting the needs of those whose p r eferred r ecreation is dependent upon trout stream fishe ries and who particularly want the big str e am type of fishery pr ovided by the Gunnison . A survey by the Colorado Game and Fish Department shows t hat 90 pe rcent of the State' s licensed fishermen fish t r out streams and 50 percent confine their efforts en­ tirely to t hem. The Gunnison Rive r and its t ributaries r eceive nearly 20 percent of the t otal fishing pressur e applied to trout streams in the State. Over t he past 5 year s (1952 - 1956) that pressur e has in­ c r eased 1 5 percent as i ndicat ed by increased license sales. 79 . Ther e is national need also for the type of fishing oppor­ tunity the Gunnison River has to offer . Fr om many states and from a s far away as New Jersey, Florida, and Cali fornia , fishermen came to fish the Gunni son in 1956 as they have done for many years past. Over one-fourth~6 percent) of the tot al numbe r of fishermen we re nonresi­ dents . Over two-fifths (43 pe rcent) of the total man-days of fishing was done by nonresidents . 80 . Fishing the Gunnison River adds excitement and inter est to the sport of trout fishing . The Gunnison is one of the "big name" s treams among America' s trout wate rs . The fisherman has a sense of keen anti ci pation, knowing the r e a r e " big ones"lying in the depths . Yet t her e are plenty of smalle r ones which keep his success high and his interest sharp . The powerful t ug of the curr ent warns him as he ventures perhaps a little farther than he should in or der to place his lure or bait in just th:: "right" spot . He realizes, with a little thrill of danger, that the odds will be in favor of the fish if he gets a str ike t hen and that he well may get a ducking . The Gunnison is "big water" , with lots of room to work a fly and for a trout to maneuver, yet ther e is a sense of intimacy as the fisherman comes to know the peculiar characte ristics ·which mark a ce rtain be nd, a certain pool, a certain riffle . There is infinite vari ety t o chall enge t he fisherman ' s ability. Nature, as in all good trout streams , provided its own "fish attractors", and t he knowing angler directs hi~ best efforts at those points . 81 . Because the Gunnison is " big water", many fishermen can use it each day without feeling crowded or overfishing the resour ce . Con­ sidering the present and future demands, such streams are few thr ough­ out the country. They r epr esent an irrepl aceable resource.


82. In comparison with the existing trout fishery, the lakes of Curecanti unit will not be a replacement. As stated in Colorado Out­ doors, May - June 1957, "Along about 1950 it was becoming pretty obvious that trout fishing in most of our big mountain reservoirs left a lot to be desired". There is no evident means of improving such environ­ ment for trout. Even for such trout as are produced, the most effec­ tive way of fishing is by trolling or bait fishing. If Kokanee salmon are introduced and are successful in building a large popul ation, it will improve the catch per man hour. But Kokanee are not intended to r eplace trout as a sport-fishing r esource . They are good fish, but not a comparable game fish. Their mouths are soft and they must be handl ed gently when hooked . They are caught gene rally while trolling at depths of twelve feet or so--they seldom if ever take a fly. In Colorado waters, Kokanee attain a maximum length of 16 inches and a weight of 1 to 1 1/2 pounds. 83 . Thus, trout lake s created by r eservoirs and subject to fluc­ tuation provide a fishery whose recreational aspects are entirely dif­ ferent from trout streams . True , many peopl e enjoy lake fishing and that is evident in the fishing use being made of the existing lakes. It is also evident, however, that an abundance of this type of fishery already exists. With other reservoirs already under construction and with a State-Federal program under way t o create lakes especially de­ signed to produce good fishing, it does not appear that there is any need, from the standpoint of fishing r e creation, for the lakes of the Curecanti unit. Hunting recreation 84. The major wildlife problem in connection with Curecanti unit concerns mule deer. In meeting recreational needs dependent upon this r e source, Colorado has to take into account several factors which are plainly evident . The present amount of winter range is fixed, barring some cataclysmic change in the world climate . The p r esent size of the herd is in excess of the carrying capacity and must be reduced until it is in balance with that capacity. This means that even if winter range acreage does not change, the future number of deer available for hunting will be smaller. 85. On the other hand, between 1948, when 89,132 deer licenses were sold, and 1954, when the number was 114,924, there was an average 3 percent yearly increase in licenses sold. Should that increase con­ tinue, the numbe r of persons hunting deer in Colorado will have doubled in 35 years. They will numbe r over a quarter of a million persons. It is probable that the increase will exceed 3 percent annually,judging from factors such as the increasing population, greater l eisure time, and the fact that a growing percentage of all people are turning to outdoor r ecreation. Hunters of the future will be restricted to the harvestable surplus of herd s in balance with the quality and amount of winter range.


86. These herds will not only be important in meeting the needs of Colorado residents. In 1955, 22 percent of the hunters were non­ residents. Although the greatest numbers were from Texas, Kansas, Oklahoma, Missouri, and California, in that order, they came from 25 different states to hunt deer in Gunnison County. More and more, hunt­ ers from other states (and particularly those states with limited deer populations) will look to Colorado for deer hunting recreation. 87. The present situation, where temporarily the herds are under utilized and two deer per license can be allowed, will change and every deer that Colorado herds can produce will be utilized. A somewhat lower success ratio will become the rule. It is important therefore that no winter deer range be sacrificed needlessly. The State is do­ ing what it can to protect certain key areas. In fiscal years 1955 and 1956, the Colorado Game and Fish Department purchased 15,514 acres of winter deer range on Piceance Creek in Rio Blanco County, for which they paid $337,500. Management of six other deer winter ranges, or speaking more exactly, portions of other winter ranges,which had pre­ viously been acquired, cost an additional $67,350 during that period. One of these latter is immediately adjacent to the Curecanti Reservoir site. But, although acquisition and management of winter range is a major part of the Department's program and a very important one for the good of Colorado 1 s deer herds, the vast amount of range required by herds large enough to meet existing and future demands make.it ·~ evident that a State range acquisition program is not the entire answer. 88. Each acre of winte r range will greatly increase its value in the coming year. Particularly is this true in the major hunting areas such as the Gunnison. Gunnison County ranks among the top 10 of 58 counties in use by resident deer hunters; it ranks among the· top S of 46 counties in number of nonresident hunters. The loss of 6,140 acres of winter range will decrease the capability of the big-game resources in Colorado to meet recreational needs. The loss will be particularly significant in that it affects the west Gunnison herd. It is a loss that cannot be replaced.

Previous Objections to Curecanti Reservoir Site 89. The Bureau of Sport Fisheries and Wildlife has consistently pointed out the adverse effects of the Curecanti unit and project pro­ posals which preceded it upon fish and wildlife resources in the Upper Gunnison Basin and, consequently, upon recreational values. 90. A Preliminary Report on Fish and Wildlife Resources in Re­ lation to the Colorado River Storage Project, Colorado River and Tri­ butaries above Lees Ferry, Arizona, January 10, 1949, voiced objection to the Cottonwood Gulch Dam site, located 1 mile downstream from the

26 BUREAU OF SPORT FISHERIES AND WILDLIFE mouth of Lake Fork of the Gunnison River, and the reservoir it would have created. Our report titled A Preliminary Report on Fish and Wildlife Resources in Relation to the Colorado River Storage Pro ject and Participating Projects dated January 1951, in referring to the effects of Blue Mesa Dam and Curecanti Reservoir, said, "Construction of the dam at Blue Mesa would destroy the valuable established fishery and in exchange would leave a fluctuating reservoir,much less attrac­ tive and unlikely to maintain a good trout fishery .... The reser­ voir would inundate critically needed winter range for deer .••• In view of the extremely harmful effects that construction will have on ffish and/ wildlife resources and lack of feasible means for mitigat­ ing these anticipated losses, the/Fish and Wildlife/ Service recom­ mends that investigation of alternate sites be continued ...". A letter report to the Regional Director, Bureau of Reclamation, dated January 18, 1955, expr essed opposition to construction of Curecanti Reservoir, pointing out that such major wate r-devPlopment projects as were considered necessary and desirable/on Gunnison River/should be constructed downstream from the North Fork of the Gunnison River. The Bureau of Sport Fishe ries and Wildlife is opposed to construction of Curecanti unit or any other project in the Upper Gunnison Basin which will significantly damage fish and wildlife resources.

Consideration of Alternative Sites 91. Although Public Law 485, which authorized the Colorado River Storage project and provisionally authorized the Curecanti unit, pro­ vided that the Junipe r s ite on the Yampa River in northwestern Colorado be studied concurrently, it is evident from the legislative history of this law that the Juniper site was considered as an alternative. The Bureau of Sport Fisheries and Wildlife has made sufficient study of the Juniper site and the lands and waters which would be influenced by it to know that fish and wildlife losses would be slight, while there are potentialities for creating extensive new recourses and bringing business opportunities to a portion of Colorado which now supports relatively few people. There would also be advantages, from the fish and wildlife aspect, to construction of the DeBeque Dam on the Colorado River or the Whitewater Dam on Gunnison River, each of which would be a f ew miles upstream from Grand Junction, Colorado. 92. Circumstances peculiar to the Curecanti unit make it impos­ sible to achieve a significant measure of mitigation of losses. The 33 miles of rive r downstream to the North Fork are virtually inaccess­ ible. The stream being inundated cannot be replaced in size or qual­ ity. The deer range being destroyed means an irreplaceable loss. There are other possibilities for water development in the Gunnison Basin and nearby watersheds which could be constructed with less dam­ age to fish and wildlife and with opportunities for mitigation of losses or enhancement of the r esources, provided sufficient priority

27 BUREAU OF SPORT FISHERIES AND WILDLIFE was given in the planning of design and operation. Other high alti­ tude reservoir sites in the Upper Gunnison Basin, similar to Taylor Park, located on such streams as East River, Tomichi Creek, Cochetopa Creek, Ohio Creek, and Lake Fork of the Gunnison River offer such op­ portunities. It would seem possible that these reservoirs might be operated in such fashion as to provide a pool of firm power and also to provide adequate streamflows to maintain the outstanding quality of the stream fisheries in the Upper Gunnison Basin. 93. In a Status Report by the Bureau of Reclamation, on Curecanti unit, dated February 1956, it was stated that, although ultimate power load would be large enough to absorb energy from all economically feasible hydroelectric sources, the development of Curecanti unit could be deferred until needed to meet growing market load provided other units of the storage project were built first . Among the alter­ naitive hydroelectric potentialities the report mentions: (1) other units of the Colorado River Storage project, (2) the DeBeque project, (3) the White-Colorado Diversion project, and (4) the Animas-La Plata project. Since Curecanti unit as planned is e ssentially a hydroelectric power project, it is assumed that no other purpose would suffer if it were deferred or if it were ne ver constructed at all.

National Importance 94 . Fish and wildlife resources, such as those present in the Gunnison River Basin, provide recreation for a sizeable proportion of the Nation's population. As indicated in a National Survey of Fishing and Hunting for 1955, twenty-five million persons 12 years of age and over fished or hunted during that year. A large numbet of additional persons enjoyed recreation in the form of wildlife photography, bird watching, and nature study. With the tensions of modern living, more and more Americans are finding a need to seek healthful relaxation in the out-of-doors. More than any other time in the history of this Nation, outdoor recreation, including fishing and hunting, is being r e cognized as one of the great basic needs of the American people. 95. The Upper Gunnison Basin is an area of land and water which is unusually well suited for fish and wildlife . The Gunnison River is famous across the Nation as one of the country's outstanding trout streams. National publications frequently devote space to this fish­ ery, and sportsme n travel long distances to t e st their skill in the r enowned Gunnison. Deer and elk hunters, t oo, come not only from Colo­ rado, but from other Stat es as we ll to pursue their sport. We believe these resources should be accorded a paramount position in development plans for the basin. This does not mean that all other interests must be kept out or eliminated. It simply means that other objectives should be achieved only to the degr ee possible after giving perpetuation and development of fish and wildlife resources first priority. There is a great deal of money being spent and an active program being

28 BUREAU OF SPORT FISHERIES AND WILDLIFE conducted by private individuals as well as public agencies, such as the U.S. Forest Service and the Colorado Game and Fish Department, to expand facilities and maintain or improve the capacity of fish and wildlife resource s to meet recreation needs. With proper planning, encouragement, and financial backing, the progress of developments re­ lated to fish and wildlife resources can be stepped up to adequately meet people's needs. The Upper Gunnison Basin is an area of strategic importance for fish and wildlife , and a positive, long-range program for preservation and development of the se resource s on a basin-wide scale is now in order.

Economic Aspe cts 96. The fishery of the Gunnison River is considered to be of national significance , and its preservation is in the national inter­ est. Although the Gunnison Rive r Basin also contains valuable big­ game habitat and receives heavy hunting use, it is famous primarily for its trout fishery. The re is no known method of expressing the full importance of thi s unique resource in monetary terms. Its pre­ servation must be justified on the basis of intangible considerations. No attempt is made in this r eport to assign a monetary value to the fish and wildlife resources of the proje ct area and the effects the re­ on of project construction. 97. A trout fishery such as that of the Gunnison River is suffi ­ ciently rare throughout the country that the attraction which it offers faces little compe tition . The Curecanti unit lakes, on the other hand, will be in direct compe tition with other reservoir lakes in Colorado and elsewhere . Narrow Gauge, Morrow Point, and Crystal Lakes will be at a disadvantage because of low productivity and inaccessibility. Curecanti Lake will be competing with lake s as good or better which are closer to cente rs of population, as well as with Taylor Park and other relative ly ne arby lakes . 98. Not only will construction of the Curecanti unit eliminate a sizeable portion of the famous Gunnison River fishe ry, but it will also provide an opportunity through r eplacement storage for the sub­ sequent impounding of upstream portions of the river and its tribu­ taries which would further r educe stream fishing opportunities in the Gunnison River Basin. 99. Although the fish and wildlife values of the basin cannot be expressed in monetary t e rms, expenditure s by fishermen and hunters us­ ing the area provide an indication of the i mportance of fishing and hunting to the local economy . On the basis of recent surveys by the U.S. Fish and Wildlife Service of sportsmen using the are a and on the basis of expected future use, it is estimated that expenditur es in con­ nection with fishing and hunting will average about one and a quarter

29 BUREAU OF SPORT FISHERIES AND WILDLIFE million dollars annually ove r the next SO years. A substantial portion of these expenditures will r epresent r evenue t o l ocal businessmen in the vicinity of the Curecanti unit. Construction of the unit will re­ sult in a loss of about three- quarters of a million dollars annually in the busine ss generated by these fishing and hunting activities . Although this r epre se nts a significant mone tary loss, it is not con­ sider ed in the present instance a s a true indication of the matchless public assets for outdoor r ecreation which will be lost if this nation­ ally significant fish and wildlife arm is destroyed or seriously dam­ aged.


100. The r esources of the Gunnison River are instrumental in mee ting the needs of Coloradans and a host of nonresident trout fish­ e rmen for the sporting challenge of a "big -stream" fishery. Moreove r, as ye t ther e is still opportunity for increased utilization of this s tream before eithe r the fishery r esource is overexpl oited or the fishermen are subjected to the crowded conditions oft e n encountered elsewhere . By contrast, the r eservoirs to be provided by the project and the harvests they will yiel d are be lie ved an inadequate substitute for the present str eam f i shery and, in addition, a duplication of op­ portunitie s already abundant elsewher e in the State . 101. Reduction in the amount of mule deer winter range i s the major wildlife problem of the Curecanti unit. The Colorado Game and Fish Department is concentrating on the p rotection and acquisition of key winte ring a r eas in the Stat e as one of the means of sustaining the big-game populations and meeting the r elated demands for hunting oppor­ tunities . The importance of the deer r ange in Gunnison County, already evident in the high preference given it by resident and nonresident hunters alike, is expect ed t o increase with each passing year. Loss of the range in the Cure canti Reser voir area would complicate an al­ r eady difficult problem of habitat pre servation. 102. The hunting and fishing expenditure s dependent upon the fish and wildlife r esource s of the p r oject ar ea provide a significant contribution t o t he gene ral economy of the Upper Gunnison Basin, as well as to the business enterprises al ong the r oute s used by sports­ men in r eaching this section of Col orado . Moreove r, if the Curecanti unit is built, pe r sons dependent upon t his source of revenue will suf­ fer serious l osses . 103. Since 1949, the Bureau of Sport Fisheries and Wildlife has consistently pointed out the adver se effects of the Curecanti unit and preceding proposals upon the fish and wildlife r esources of the Upper Gunnison Basin. As an alte rnative offering smalle r l osses and great e r possibilities for the creation of new r esources and allied business

30 BUREAU OF SPORT FISHERIES AND WILDLIFE opportunities, this Bureau suggests the Junipe r Reservoir site on the Yampa Rive r as a possible substitute . DeBeque Dam on the Colorado Rive r and Whitewate r Dam on the Gunnison River ar e a lso advanced as alternate development possibilities with the i dea that, in comparison with the Curecanti devel opment, the r esultant damages to fish and wild­ life resource s would be f a r l ess and the opportunit i es for mitigation of losses or possible enhancement far greater. The same is true for the alternate development of high altitude r eservoir sites such as might be located on East River; Cochet opa, Ohio, or Tomichi Creeks, or the Lake Fork of t he Gunnison. In all the f or egoing possibilities, the best r esults would require an early consideration of fish and wildlife requirements during the p l anning of project design and operations. 104. Recr eational use has been assigned the highest p r iority for certain rivers in the United Stat es, such as the Curr ant River in Missouri and the Namekagon River in Wisconsi n . The intangible but no l e ss r eal value of these streams and their environs for recrea- · tion we re determined by the peopl e and by the courts t o outweigh the values resulting from alte rnative uses. It follows, t herefore , that to destroy such r ecreational val11e in order to promot e some other use would be unsound. The r e is no doubt that r ecr eati onal values of an importance equal t o these othe r s are threatened by construction of Curecanti unit. The Gunnison River and its watershed upstream from the mouth of North Fork can be of greatest benefit to the greatest number if its inhe r ent natural qualities are pr eserved and developed for recreation, along with other uses which will not damage or alter appreciably the outs tanding quality of its fish and wildlife resources . 105. The re is no feasible means of r eplacing the above values in kind and quality1 nor of significanly mitigati ng the loss to the people of Colorado and the Nation that will r esult if Cure canti unit is constructed. The fishery l oss, in particular , will be a signal one . Not only are the good stream fishery areas open to t he public in Co l o~ rado diminishing each year, but the reach of rive r involved is one of the "big-wate r" trout streams that already provides the exact t ype of recreation preferred by a g r eat number of fishermen.


106 . It is recornrnened- - (1) That the Cu r ecanti unit not be constructed because it would destroy a nationally significant stream f ishe ry of a type which is becoming increasingly rare and for which t her e is a growing demand .


(2) That any planning for water-development proj­ ects in the Upper Gunnison Basin give first priority to the preservation and enhancement of fish and wildlife resources. (3) That Federal and State conservation agencies cooperate in the development of plans to pro­ vide for preserving and enhancing the stream fishery of the Upper Gunnison River Basin and facilitating the increased public use and en­ joyment of the fishery. /s/ John C. Gatlin John C. Gatlin Regional Director