TPWD 1961 F-5-R-8 #642: Fisheries Investigations and Surveys of the Waters of Region 3-B: Basic Survey and Inventory of Species in the Rio Grande River of Texas in Region 3-B

--- Page 1 --- JOB COMPLETION REPORT As Required By FEDERAL AID IN FISHERIES RESTORATION ACT Federal Aid Project No. F-5-R-8 Fisheries Investigations and Surveys of the Waters of Region 3-B Job No. B-15 Basic Survey and Inventory of Species in the Rio Grande River of Texas in Region 3-B Project Leader Lawrence S, Campbell H. D. Dodgen Executive Secretary Texas Game and Fish Commission Austin, Texas Marion Toole Eugene A. Walker D-J Coordinator Director, Program Planning February 14, 1962 --- Page 2 --- ABSTRACT Sampling of fish populations included 71 gill net collections and 31 sein- ing collections from the Rio Grande River between El Paso and the mouth of the Devil's River. Examination of thousands of fish obtained by seining and 1,523 fish captured in gill nets established occurrence of 42 species of fish belonging to ll families. Distribution and relative abundance of fish were found to con- form to three basic ecological associations: turbid intermittent pool, permanent flow clear water, and turbid indolent flow. The basic distribution patterns were as outlined for the Chihuahuan Biologic Province by Dr. Clark Hubbs. Floods, as they occur in the Rio Grande, are believed to be detrimental to propagation of many game fish. This, plus water quality, limit production of some game fish such as centrarchids. The upper third of the stream, from El Paso to Presidio, is dominated by rough and forage species that were 94.27 per cent of the netted sample. The clear water associations produced 33.49 per cent usable game fish and represent the most productive stream areas in the region. Data on the lower third of the stream, from Regan Canyon to the mouth of the Devil's River, are insufficient and tends to be biased by the conditions that prevailed when field work was done. Generally, the Rio Grande is the most productive stream in the region, and is the longest and most desirable fishing area that is now open to public access without charge. For that reason, it is afforded priority for fishery management. A new reservoir, now under construction near Del Rio, should be investigated to determine what may be done to promote game fish production. Reconnaissance studies in the future should include work to provide additional data on the lower third of the stream. Inquiries should be made to determine if flood retention structures on tributaries of the stream can be utilized for public fishing. The canal system in El Paso County should be re-examined in an effort to find means of employing these sturctures for that purpose. --- Page 3 --- JOB COMPLETION REPORT State of Texas Project No. F-5-R-8 Name: Fisheries Investigations and Surveys of the Waters of Region 3-B Job No. B-15 Title: Basie Survey and Inventory of Species, as well as Their Distribution in the Rio Grande River of Texas in Region 3-B Period Covered: April 1, 1960, to February 28, 1961 Objectives: To gather fundamental data on the above water in regard to physical, chemi- cal and biological aspects, and to determine the distribution of species present and their relative abundance. To also determine ecological factors influencing species distribution. Techniques Used: Standard procedures were used which supplied the information necessary to complete stream survey forms similar to those given by Lagler in his 'Handbook of Freshwater Biology". Inquiries and investigations to locate means of access to the river, and reconnaissance trips on the stream by boat or raft were neces- sary to locate netting and seining stations. Seventy-one overnight sets were made with gill nets at 28 locations. Nylon gill nets were used that measured 125 feet in length and 8 feet in depth, The nets were made up of 25-foot sections with mesh sizes beginning with l-inch Square mesh and increasing in each succeeding section by one-half-inch intervals to a 3-inch square mesh. An attempt was made to use hoop and fyke nets for sampling; however, unex- pected increases in stream flow rendered this effort non-productive. Seining collections were obtained at 31 locations. Each location or col- lection consisted of several drags with either a 12- or 20-foot one-fourth-inch mesh nylon straight seine. A sample of the fish captured at each location was examined in detail and the relative abundance of various species was noted. Individuals whose identity was not positively established when examined in the field were preserved and identified in the laboratory. Detailed water quality data were obtained for six locations on the river. Data included determination of pH, total solids, chlorides, sulphates, sodium chloride, dissolved oxygen and biochemical oxygen demand. This detailed analysis was provided by the International Boundary and Water Commission and by the State Health Department, Hydrology records were obtained from those organizations and from the United States Geological Survey. Water temperatures, turbidity and pH were taken at 21 stations. Rotenone sampling of pools was planned but not completed because the desired and necessary conditions were not encountered during field work. --- Page 4 --- Introductory Statement The Rio Grande River rises on the eastern face of the continental divide in southern Colorado. At the river's cold water source, temperatures average about 14° F, in January, and near 50° F, in July. Precipitation averages about 5 inches per year. At the semi-tropical mouth, temperatures average near 50° F. in January, and about 68° F. in July. Precipitation there averages between 20 and 30 inches. From source to estuary, the stream falls nearly three miles, and meanders nearly 1,900 miles, making the Rio Grande the second longest river in the United States. The river commonly does not carry a great volume of water, and in many places, especially where it traverses desert, the stream is sometimes dry. Local storms create flood conditions that subside in a few hours, and most of the annual run-off, which averages nearly 4,000,000-acre-feet, enters the river from this sporadic source. Where flow is permanent, it is usually sustained by springs and seepage. The topographic basin, which includes 335,500 square miles, is semi-arid and only about one-half of that area, 171,900 square miles, is contributive. After the river leaves the mountain streams, it intermittently cleaves through mountain canyons, wide level plains, and desert terraces. Pastoral valleys, varying in width from a few hundred yards to a few miles, are inter- spersed along the stream for three-fourths of its length. The river and these valleys are the artery for biologic and economic life within the river basin. The river receives comparatively few tributaries, and many are entirely dry except for sporadic flow. Man's influence and use of the river pre-dates recorded history, but from the year 1600, when Spanish colonization encouraged settlement, irrigation in the rich alluvial bottom land has progressed toward total usage of the river's water. Today, over 2,500,000 acres are irrigated from the river's watershed. Primarily to control irrigation, a series of reservoirs have been constructed. These include Rio Grande, Continental, Santa Maria, Terrace, Mountain Home, Sanchez, Costilla, El Vado, Bluewater, Elephant Butte, Caballo, Almogordo, McMillan, Avalon, Red Bluff, Willacy, McClure, Devil's Lake and Lake Walk on the United States watershed. In Mexico they are Boquilla, La Colina, Rosetilla, Madero, Venustiano Carranza, Marte Gomez, Culebron, and Palito Blanco, These structures, with International Falcon Reservoir, effectuate storage for 8,000,000 acre feet of water. Work included in this survey was restricted to the Rio Grande River and does not include tributaries. Survey reports for the Devil's River are included under Project No. F-9-R-2, Job No. B-4, for the Pecos River under Project No. F-5-R-5, Job No. B-13, and for Terlingua Creek under Project No. F-5-R-2, Job No. B-11. In all, 680.1 miles of stream, beginning with the American Dam in El Paso and ending at the mouth of the Devil's River, were in~- cluded in this investigation. Findings: Most of this mid-section of the Rio Grande can arbitrarily be classified as belonging to, or being dominated by, one of three basic ecological associa- tions. (See Figure 1.) These are: turbid intermittent pool, permanent flow clear water, and turbid and indolent flow associations. --- Page 5 --- te: In an attempt to present a clear picture of the stream and its fishery potential, some materials and data obtained will be grouped and included under each association as it is taken up in discussion. This is also done so that the influence of the various associations on species distribution and relative abundance of species will be more apparent, and to attempt to prevent mislead- ing data that would result from overall averages. Intermittent Pool Associations: Nearly all of the stream that should be classified in this category is located above the river's confluence with the Concho River of Mexico. For over 293.5 miles, from El Paso to the mouth of the Conchos, the stream and its included fish life are adversely affected and regu- lated by intensive irrigation demands. As is illustrated in hydrology data in Tables 1 through 9, flow expands to great proportions only to return to a mini- mum flow within a few days. In that area of the state, over 1,200 miles of canals and laterals are constructed that carry water from the river to fulfill irrigation commitments for more than 155,000 acres annually. Other irrigation by wells from subsurface sources directly influence stream flow and are of ex- treme consequence during non-flow periods to residual pools. Irrigation demands are greatest in late spring and through the summer. During that time the stream is usually rapidly diminished until it is reduced to pools. These are then decreased by ‘evaporation and seepage as water percolates into sub- surface sands to fill vacancies created by withdrawals through wells for irrigation. Through these processes, the chemical composition of the remaining water is affected, and salinity, total dissolved solids, insoluable carbonates and pH increase, The stream bed is wide throughout most of this valley and flow velocities, except during occasional flooding, are rarely sufficient to adequately carry off suspended silt and organic debris, This debris decays rapidly in warm waters which sometimes exceed 90° F. In many instances, dis- solved oxygen is reduced below critical requirements for many game fish, while carbon dioxide content nears saturation, Turbidity usually increases, More specific and detailed dataare available in Tables 1 through 11, and as shown therein, oxygen deficiencies occasionally occur even when flow is above average. As a result of these conditions, most game fish and/or their progeny (if any) are destroyed, At the same time, undesirable tenaceous fish survive and suc- cessfully reproduce. Even when game fish of advanced sizes are released in these waters, their survival is at best temporary. At all gaging stations from the American Dam to Upper Presidio, lack of flow frequently occurs and usually lasts for ten or more succeeding days within each year, At the El Paso-Hudspeth County line, about mid-point of this stream area, flow was re- corded for only 13 days in 1952, and for only 4 days in 1954. A few spring areas, such as the radioactive waters of Indian Springs in Hudspeth County, are present, Within these few widely separated spring areas, a few game fish survive. In El Paso County, the terrain is uninhibiting and most of the stream is available and accessable to the public for fishing. However, from the Hudpseth County line to Presidio, access is often difficult or near impossible. Canals and a few small control reservoirs supply nearly all of the fishing for this area, and apparently offer the only potential means of meeting the public demand for recreation with the presently existing facilities. (See Figure 2.) Permanent Flow Clear Water Associations: Beginning a few miles below the mouth of the Concho River, the stream bed narrows and the average fall of the stream increases from 3.89 feet per mile to 4.78 feet per mile. The frequency of --- Page 6 --- a pa walled canyons increases and these constrict flow and increase velocity of the stream, From here, and continuing for many miles, a series of steps in the stream bed give momentum to flow between pools, and this movement is reduced as the water passes through the more level gradient of the pools. A build-up of ground water increases and tends to stabilize flow as irrigation demands decrease. Within 78 miles, a rapid transition takes place. The pools become more frequent and less turbid as flow from the subsurface is forced upward after appearing and dissappearing many times in the stream bed, Water movement through pools is more pronounced and a permanent flow finally establishes between pools. Stream ecology changes so radically that it appears to be virtually unrelated to the previously described intermittent pools, Periodic floods and confined permanent flow of the stream are retained in narrow canyon walls such as Santa Elena, Mariscal, Boquillas and others, and the increased scouring action of the current sweeps gravel and rock rubble clear of debris that would otherwise be deposited from above. Clear waters are protected by canyon walls during much of the day from direct exposure to sunlight, and as a result, extreme temperatures are less common, As shown in Tables 12 through 14, the water quality improves and food production and other factors are conducive to game fish survival. This stream area, from a few miles below the mouth of the Concho River to a few miles below the mouth of Regan Canyon, is about 200 stream-miles long and is the largest and most desirable area of stream within this region that is now available to the public. However, this stream area is largely inaccessable and it was necessary to work much of the stream by floating trips that often included portages, (See Figure 3.) Future construction of access roads should make clear water associa~ tions more usable to the public. Turbid Indolent Flow Associations: A few miles below the mouth of Regan Canyon the stream again broadens to fill the expanded canyon walls, velocity of flow decreases as gradient is reduced to 3.02 feet per mile, Meanders are broader and turns are longer and more gradual, Much of the silt and debris carried from above by flood waters is deposited in the stream bed, on bars at turns in the river, on occasional flood plains and along narrow shelves at the foot of canyon walls, The stream's basic direction shifts to align itself almost directly with the daily travel of the sun during the summer and stability of flow reduces as springs exercise less influence, The stream is usually very turbid, and in summer, water temperatures sometimes build up to and exceed 90° F. As shown in Tables 15 through 18, water quality decreases as salinity, total dissolved solids, and pH increase beyond desirable limits. Dissolved oxygen deficiencies are common, and excessive carbon dioxide content is frequently recorded, Fluc- tuations in the stream level prevents reliable spawning activity of many game fish and all factors tend to favor production of many undesirable species. Where infrequent springs or clear water flow enters the stream, such as the mouth of the Pecos and Devil's Rivers, Goodenough Springs, San Felipe Springs and a few others, game fish congregate and are sustained by those conditions, The 109 miles of stream between Regan Canyon and the mouth of the Devil's River are largely in~ accessable, This is partly because of steep canyon walls that extend, virtually unbroken on the United States side, along the entire stream course. Also, land- owners are not inclined to permit access to the river by persons who are unknown to them, Since this stream is an international boundary, their reasoning is obvious. This final association may be said to epitomize the popular public concept of the lazy Rio Grande, (See Figure 4.) Other Basic Factors that Directly Influence Fish Life: As previously stated, local floods of a sporadic nature occur every year. However, more extensive --- Page 7 --- i) =5- flooding is not uncommon, From 1902 to 1960, flooding that affected at least one or more of the described ecological areas occurred on 19 occasions. During that same period, seven major floods affected the entire length of the river, The effect of floods on fish life is not completely understood. However, tremendous current velocities are built up as tributaries fall into valleys. As these water levels exceed stream banks, the inundated loose soils of intensively cultivated fields are picked up and carried with the stream in great quantity. The stream load is probably greater than is common for many rivers, and is primarily made up of adobe, other adhesive clays, sand, gravel and organic debris, A smothering affect on some species of game fish or their progeny is believed to occur. It is also possible that chemicals toxic to fish, such as insecticides commonly used in agricultural practices, enter the stream during flood conditions. Many in- stances of fish kills have been reported during and immediately after flooding. (See Tables19 and 26.) Pollution is known to enter the stream from several sources on the United States watershed. Parts of Devil's River and the Pecos River are known to be polluted by oil field operations and lesser tributaries probably receive similar pollutants.The extent and total detrimental effect of this factor is not known, but hydrology and water quality data indicate that this damage may be extensive. Virtually nothing is known of sources of pollution from Mexico, However, the lack of soil conservation techniques, the lack of proper facilities for disposal of polluting substances, and public apathy where such problems are concerned is obvious. In spite of the prevailing conditions, the production of invertebrate food for sustaining fish life is often excellent, Many beetle larvae (Coleptera), primarily of the genus Berosus, are present in the coarse gravel of clear water stream beds. Other insects and larvae encountered in clear water associations are larvae of crane flies, Diptera, mayflies and their nymphs, Ephemerida, and damselflies and dragonflies, Odonata, Aquatic Hemiptera are also present. In intermittent pools and in turbid slow-flow waters, only Diptera and their larvae were abundant, A few Hemiptera were also observed. Mollusca were common but seldom abundant through the entire river. Aquatic vegetation is not regarded as constituting a major problem in any of these stream associations, This is primarily the result of scouring action of periodic floods, the normal fluctuation of the stream and in many instances constant turbidity. A complete and accurate inventory of plants present was not. possible under the conditions that prevailed when field work for this Survey was done. However, some of the more important species that are known to occur are pondweeds (Potomogeton diversiflora) with additional species of that genus probably occurring, arrowhead (Sagittaris sp.), tapegrass (Vallis~ neria sp.), yellow waterlily (Nuphar advena,, and muskgrass (Chara sp.). Positive species identification of most of these plants was impossible since such identification is often dependent upon flowering parts of the plants. It was necessary, because of other work commitments, that the survey work be done at a time when these parts of the plants were absent or were undeveloped. Along shores, cattails (Typha latifolia) were common and were especially numerous in sunny marshy areas near canals and in other places of permanent moisture. Other shore plants included were bulrushes (Scirpus americanus), rushes (Juncus nodosus)with other plants of this same genus also probably occur~ ring, sedges (Carex sp.), smartweed (Polygonium sp.), desert willow (Chilopsis linearis), dock (Rumex mexicanus), alfalfa (Medicago saliva) that had escaped --- Page 8 --- ele from domestic cultivation, Dipetalis subulata which has no accepted common name, umbrellagrass (Fuirena hispidal), common reeds (Phragmites communis), and giant reedgrass (Arundo donax). These latter reeds and reed-like plants are common on bars in the river, along shelves at the foot of steep canyon walls, and tend to border much of the stream on both sides as soil accumulations will permit. The most common trees along the Rio Grande are the cottonwood (Populus palmeri), quaking aspen (Populus tremuloides), and several species of willows (Salix nigra; Salix interior; Salix gooddingii; and Salix taxifolia). Ferns, Polypodiacae, are common in a few spring areas, Beaver (Castor canadensis) are common along the clear water associations, and were very detrimental to nets used in sampling fish populations, Nutria (Myocastor coypus) are reported in lower regions of the watershed. Species Present and Their Distribution: Several problems were encountered in establishing distribution of species. Decisions, involving the inclusion in the river's fauna of species that appeared to be endemic to springs near the mouths of tributaries, were required, In other instances, a particular species appeared to have temporarily expanded its distribution as a result of specific and unusual conditions that could not be expected to prevail for any extended period. Conformity of distribution, as governed by basic stream ecology, had to be considered. Consideration was also given to whether species introduced by hatcheries and bait dealers should be included. Field work was adversely affected by several circumstances, Flooding pre- vented effective seining during much of the time spent making collections, No accurate and reliable means of predetermining stream conditions were discovered. This was because of the inaccessable nature of the stream, the lack of knowledge of the extent of rainfall in Mexico, and because of the length of time required to reach the stream from the regional headquarters. Flooding occurred during all field work with one exception, When the frequency of occurrence of flooding is taken into account, the degree of misfortune can be apparent. Much seining effort was rendered unproductive by the expansion of the stream during flooding on shore areas that were heavily vegetated, Counts of fish taken under the limiting circumstances are regarded as being entirely misleading. Because of this, the abundance of minnows and several other species is best expressed in discussion, The seining stations worked and a description of their location are included in Figure 8. Annotated Checklist of Species of Fish Occurring in the Chihuahuan or Mid-Rio Grande River Lepisosteidae - Gars Alligator gar (Lepisosteus spatula) were common but not abundant and were taken as far west as Presidio. They were much more common in lower stream areas after permanent turbidity is apparent. Spotted gar (L. oculatus), whose presence was questioned and identity un- confirmed, was represented by a single fish from the mouth of the Pecos River. It was too large to be preserved with the ordinary equipment present when this collection was made, Longnose gar (L. osseus) was the most common species of this group through- out the stream, and was taken in abundance as far west as the mouth of the Concho River. This species probably also occurs in a few localities in the intermittent pools above, but confirmation from netting is not yet obtained. --- Page 9 --- Clupeidae - Herrings Gizzard shad (Dorosoma cepedianum) probably were the most common and rela- tively abundant species of the stream, They were less numerous but of greater size in clear water associations. Caracidae - Tetras Mexican tetra (Astyanax mexicanus) were very abundant near the mouth of the Devil's River, in San Felipe Springs, near the mouth of the Pecos River, and often abundant in other spring areas, They are probably located throughout the stream and tributaries as a result of introductions by bait dealers, None were taken west of the mouth of the Pecos River, Catostomidae - Suckers and Buffalofishes Blue sucker (Cycleptus elongatus) was found primarily in clear water asso- ciations as far west as Presidio. They were relatively abundant in a few local- ities, but never as dominating as other species of this group. Smallmouth buffalo (Ictiobus bubalus) were taken as far west as Presidio. Young fish are abundant in Big Bend National Park, but never abundant in the other stream areas, Reproduction was indicated in riffle areas, River carpsucker (Carpiodes carpio) were very abundant and the dominating species in intermittent pool associations and in turbid waters below Regan Canyon, It was encountered less frequently in clear waters with rapid flow where similar species appear to dominate. It was the most problematical species in the stream, Gray redhorse (Moxostoma congestum) was common but seldom found in abundance, and was taken as far west as Presidio. It cedes dominance to other sucker-type fish in intermittent pool and turbid associations, but may be regarded as being in contention in clear rapid flow waters, It may occasionally be dominant in this latter association, Cyprinidae ~- Shiners and Minnows Carp (Cyprinus carpio) was found throughout the watershed but much more abundant in intermittent pools and in turbid waters. Possibly the most adapt- able single species, it is regarded as being the second most problematic species in the watershed, Golden shiner (Notemigonus crysoleucas)was present and known to be intro- duced from hatcheries, It was prevalent in small reservoirs such as Lake Ascarate and those of the Diablo tributary group. Speckled chub (Hybopsis aestivalis) was apparently rare and not actually taken during this inventory. It was included in this region by Hubbs. Rio Grande chub (Gila pandora), a riffles species, was found only in clear water associations near the mouth of the Devil's River and the Pecos River, --- Page 10 --- Rio Grande shiner (Notropis jemezanus) was common but of questionable abund- ance, and apparently located only east of the Big Bend. Chihuahua (N. chihuahua) abounds from the mouth of the Concho River to the mouth of Santa Helena canyon. Tamaulipas shiner (N. braytoni) was common and in localities relatively abundant, especially in Big Bend National Park. Red shiner (N. lutrensis), the most widely spread species of minnow, was usually much less numerous than is common in tributaries. Roundnose minnow (Dionda episcopa) was common and very abundant in clear water tributaries, but not collected west of the Pecos. Devil's River minnow (D, diaboli) was found exclusively in the Devil's River. Fathead minnow (Pimephales promelas) was common and abundant as far west as the Big Bend. Mexican stoneroller (Campostoma ornatum), common but never numerous, was taken primarily near the mouth of Terhingua Creek and near Lajitas. Ameiuridae - Freshwater Catfishes Channel catfish (Ictalurus punctatus) was common but rarely abundant, and appears to dominate other species of this genus in intermittant pools and occasionally in very turbid waters, It yields dominance in clear water associa- tions. Blue catfish (1. furcatus) was probably the most important game species in the river and definitely so in clear water associations of the stream, This species tends to concentrate in clear pools below riffles and is particularly abundant near the mouth of the Pecos River and near the mouth of SantaElena Canyon, It was regarded as being the most beautiful and desirable game fish of the catfish group. Flathead catfish (Pylodictis olivaris) was common and relatively abundant for the species in a few localities, It is considered important commercially. Cyprinodontidae - Killifishes and Topminnows Rainwater killiffiish (Lucania parva) is primarily a Pecos River species, but believed to also be present in saline waters of other tributaries of the Rio Grande, and possibly in a few other specific areas of the river. Rio Grande killifish (Fundulus zebrinus) occurs in a few backwaters in the Big Bend area, and may occur near the mouth of other tributaries that offer saline waters, Poeciliidae - Mosquitofishes Big Bend gambusia (Gambusia gaigei) was found only in Graham Ranch Spring in the Big Bend National Park. --- Page 11 --- -9- Largespring gambusia (G. geiseri) was not collected, but believed to probably occur in some spring areas. Mosquitofish (G. affinis), common and abundant, was primarily found in back- waters, canals, intermittent pools, and stock tanks along the river. It was abundant near Indian Springs. Serrandiae - Sea Basses White bass (Roccus chrysops)was actually taken near the mouth of the Pecos River, but believed to migrate as far west as Regan Canyon, Centrarchidae - Black basses and sunfishes Largemouth bass (Micropterus salmoides) were not captured from the upper stream, and their status is questionable. However, the species is included in view of recent releases from hatcheries, Water quality and other data indicate that the species probably cannot be maintained without frequent reintroductions, Redear sunfish (Lepomis microlophus) was not collected but included for the same reason as largemouth bass, Green sunfish (L, cyanellus) was very common and abundant throughout the stream, Only a few of these fish were large enough to provide satisfaction to sportsmen. Bluegill (L. macrochirus) was abundant and found in virtually all locations of the watershed, but was usually too small for sport. Longear sunfish (L. megalotis) was rare in most areas, but taken in inter- mittent pools above Presidio, possibly as a result of introduction from hatcheries, White crappie (Pomoxis annularis) was rare in the stream and limited to the El Paso area. Control reservoirs and stock tanks near the river contain this species. Black crappie (P. nigromaculatus) was found only in Lake Ascarate and Devil's Lake, and also was probably released by hatcheries in the stream, Sciaenidae - Croakers, Drum and Weakfishes Freshwater drum (Aplodinotus grunniens) was taken as far west as Presidio, but was never abundant. Relative Abundance of Principal Species as Indicated by Gill Net Collections: The preceding checklist, which includes 42 species of fish from 11 families, was compiled primarily from seining collections and resulted from the examination of several thousand individuals. It is believed that relative abundance of the principal species is probably better expressed in tables of data made up from netting collections, Gill nets captured 1,523 fish and of this group, 292 (19.17 per cent) were game fish, This figure of relative abundance is higher than similar data for any of the other streams of this region. As is shown in Tables 21 through 44, most of the basic means of subsistence within the stream's waters has been diverted into unusable production, and this is especially true for in- termittent pool associations, --- Page 12 --- -10- A composite of all fish captured in the upper one-third of the stream, largely made up of the previously described intermittent pools, indicated that rough fish and forage species made up 94.27 per cent of the total fish, All game fish, 48 (or 5.73 per cent), of the total sample, were heavily parasitized and were otherwise in poor physical condition. Virtually no reproduction of game fish was indicated. In clear water associations, 33.49 per cent of the total sample were game fish in excellent condition. This figure may be conservative as netting condi- tions were regarded as tending to bias sampling toward selection of forage and rough species, Other data arealso interpreted to support this possibility. Turbid indolent associations of the lower river were apparently above the stream average in game fish production. However, the 28.27 per cent figure obtained, indicating prevalence of game species, would have been Considerably less if netting collections from the Lower Pecos River were not included. Actually, these collections could, or perhaps should, have been included in clear water associations because of the basic stream ecology. For these reasons, conclusions should not be made pertaining to the lower third of the river until future field work supplies data to fill this deficiency. Results from only four netting collections are available for the entire 109 stream miles that are between Regan Canyon and the mouth of the Pecos River. Netting also indicates that Devil's Lake and Lake Walk are more productive of game fish than is the stream where sampling indicated that about 39.94 per cent of all fish were game fish, However, the inclusion of stunted white crappie and sunfishes make this figure debatable. Conclusions: Much of the Rio Grande River is the most productive stream in the region, This is certainly the longest and most desirable stream area for fishing that is now open for public access. For that reason, it is considered logical that management of the stream should be given priority. A basic problem of inacces- sability is being reduced through the construction of new roads, and many factors point to a greater use of the stream for recreation, Certain information and data obtained in this survey are regarded as being insufficient or are too biased to support final conclusions. For that reason, additional reconnaissance work should be done in the future when time is available for that work. A speciai study should be included in future work to determine what should be done to pro- vide or facilitate maximum production of game fish in a new reservoir now being constructed in the Del Rio area. Recommendations: Further study should be made of the intermittent pool areas to determine if the extensive canal system of the El Paso area can be used to provide fish- ing, Additional inquiries should be made to determine if flood retention structures on tributaries of the stream can be employed to provide fishing for the public. _ Reconnaissance work should be included in a future effort to supply more data on the stream from Regan Canyon to the mouth of the Pecos River. A --- Page 13 --- -1l1- detailed study of the major reservoir now under construction near Del Rio should be made as soon as time is available for that work, Prepared by__Lawrence S. Campbell Approved by eer Lipate. Project Leader D-J Coordinator Date February 14, 1962 The following persons assisted in this survey: State Game Wardens Edgar Sturdivant, George Vickers, Sanford DeVoll, Harvey Adams and Norbin Taylor, the officials of the National Bank Service, the staff of the Big Bend National Park, Dr. W. B, McDougal, Dr. Omer E, Sperry, Dr. Clark Hubbs, landowners Marty King of Comstock, Clay Slack and George McCarthy of Presidio, Ray Johnson of Alpine, and others, and personnel of the United States Air Force, Literature cited: HUBBS, CLARK, DistributionPatterns of Texas Freshwater Fishes, Southwestern Naturalist 2, (2-3):89-104, April-July 1957 HUBBS, CLARK, A checklist of Texas Freshwater Fishes, Div. Inland Fisheries, Texas Game and Fish Commission, Revised June 1961 McDOUGALL, W. B., and SPERRY, OMER E., Plants of Big Bend National Park, United States Government Printing Office, Washington, D. C. Anonymous, Flow of the Rio Grande and Related Data, International Boundary and Water Commission United States and Mexico, Water Bulletin 22 Texas Board of Water Engineers, Chemical Composition of Texas Surface Waters, Bulletin 5905 Texas Board of Water Engineers, Records of Water-level measurements in Culberson, Hudspeth and Jeff Davis Counties, Texas, Bulletin 5415 Texas Board of Water Engineers, Sixteenth Annual Report of Silt Load of Texas Streams for 1953-1954 --- Page 14 --- Figure RIO GRANDE DRAINAGE BASIN (e PAs0 fo Del Ryo) STATES VITED WATERSHED ‘7, PP O-D BoylAR? CLOSED BASIN RIVERS LEGEND SS KA --- Page 15 --- «LF Figure 2 - Netting in the larger intermittent pools near Presidio. --- Page 16 --- ape Figure 3 - Portages were common in the stream areas of intermittent pool association. --- Page 17 --- ~15~ Figure 4 - Travel through Santa Elena Canyon after permanent flow is established. --- Page 18 --- =16— Figure 5 - Setting gill nets near the mouth of Horse Canyon on the Black Gap Wildlife Management Area. --- Page 19 --- my Figure 6 - The turbid-indolent association at Langtry. --- Page 20 --- -18- Figure 7 - The mouth of the Pecos River near Comstock. --- Page 21 --- 10, lls 12, 13; 14, 15, 16, 17. 18. 19, 20, 21. 22. 23, -19- Figure 8. Location and description of seining stations Lake Ascarate, located in the city of El Paso in Ascarate Park in the south- east quarter of the city. Rio Grande River at Island Station near Clint, Texas, 27 stream-miles below the American Dam on rectified channel. Fort Quitman, 81 stream-miles below the American Dam at a historic site. Indian Springs, a health resort southeast of Sierra Blanca near the mouth of Quitman Arroya. Upper Presidio Station, 7.8 miles above the confluence of the Concho Rivers of Mexico near Chinati. Mouth of the Concho River, 3.7 miles above International Bridge in Presidio. Lower Presidio Station, two miles below the mouth of the Concho River. Mouth of Alamito Creek, six miles below and east of Presidio. McCarthy Farm, about eight miles below or east of Presidio. Clay Slack Farm, about five miles east of Presidio. Redford Station, located 1.5 miles south of Redford community. Lower Redford Station, located four miles east of Redford. Upper Lajitas Station, four miles northwest of Lajitas. Lajitas, one mile above to one mile below Lajitas store. Lower Lajitas Station, approximately four miles east of Lajitas. Entrance of Santa Elena Canyon, approximately eight miles east of Lajitas. 7. tet bas. fa Be tepeeg: Mouth of Santa Elena Canyon and mouth of Terlingua Creek, about a 500-yard area near thesg locations. Big Bend National Park. Castolon Station, one mile below Castolon. Big Bend National Park, Smoky Creek Station, located about one mile below the mouth of Smoky Creek. Big Bend National Park. Johnson's Ranch, Big Bend National Park. Solis Ranch Station. Big Bend National Park. Graham Ranch at Hot Springs. Big Bend National Park. Boquillas Station, in riffle areas near crossing to village of Boquillas. Big Bend National Park, --- Page 22 --- 24, 25. 26. 27. 28. 29. 30. 31. 10. ll. 12, ~30- Stillwell Crossing Station, one mile radius of this crossing, Blackgap Wild- life Management Area, Texas Game and Fish Commission. Mouth of Horse Canyon Station, near mouth of this canyon, Blackgap Wildlife Management Area, Texas Game and Fish Commission, Maravallis Creek Station, area of mouth of this creek, Blackgap Wildlife Management Area, Texas Game and Fish Commission. Regan Canyon Station, near mouth of this canyon, about 30 miles south of Sanderson. Langtry Station at Langtry. Goodenough Springs, 12 miles southwest of Comstock at springs. Pecos River Station, area near the mouth of the Pecos River. Devil's River Station, area near the mouth of the Devil's River. Figure 9. Location and description of gill netting stations Lake Ascarate, located in the city of El Paso in Ascarate Park in the south~ east quarter of the city. Upper Presidio Station, 7.8 miles above the confluence of the Concho Rivers of Mexico. Mouth of Concho River, 3.7 miles above the International Bridge. McCarthy Farm, chess: ciate miles below and east of Presidio. Clay Slack Farm, about five miles east of Presidio. Lajitas Station, one mile above and one mile below Lajitas store. Lower Lajitas Station, four miles below Lajitas. Upper Santa Elena Station, four miles above entrance to Santa Helena Canyon. Mid-Santa Elena Station, in canyon about two miles above mouth. Mouth of Santa Elena Canyon., at mouth of Terlingua Creek, Big Bend National Stillwell Crossing Station, at crossing and for several miles below to the mouth of Horse Canyon, Blackgap Wildlife Management Area, Texas Game and Fish Commission. Horse Canyon Station, at mouth of this canyon and extending to the mouth of Marvallis Canyon, Blackgap Wildlife Management Area, Texas Game and Fish Commission. --- Page 23 --- 13. 14, 15; 16, 18. 19, 20. Zi. Maravallis Station, at mouth of this canyon and extending below and east along the river for seven miles, Blackgap Wildlife Management Area, Texas Game and Fish Commission. Langtry Station at Langtry. Rio Grande River above the mouth of the Pecos River, the area beginning two miles above the mouth of the Pecos River and to the mouth. Rio Grande River at the mouth of the Pecos, the stream area within one mile of the mouth of the Pecos River. Pecos River above mouth, two miles above the mouth of the Pecos River. Rio Grande River below the Pecos River, the area within two miles below the mouth of the Pecos River. Devil's River Station, the area within one mile of the mouth of the Devil's River. Upper Devil's Station, Devil's Lake and Lake Walk. --- Page 24 --- -22- Table 1. Rio Grande River below American Dam Extreme Flow From Records: Momentary: Maximum 6,770 second-feet on May 18, 1942, with a gage height of 9.77 feet. Minimum .1 second-foot on November 15, 1954. Average Flow in Second-Feet Daily: : Max. 6,040 May 20, 1942 Min. wl Nov. 15, 1954 Monthly: Max. 4,880 May 1942 Min. 25 Nov. 1954 Yearly: Max. 1,510 1942 Min. 29.9 1954 Average Flow Period June 1938-1954 Acre-Feet Average Maximum Minimum January 7,818 12,000 3,250 February 4,651 32, 800 521 March 3,121 17,500 91. April 11,089 74,500 2,230 May 29,639 300,000 4,290 June 25,148 250,000 300 July 20,504 155,000 2,070 August 18,067 114,000 3,070 September 17,095 124,000 198 October 3,508 19,000 197 November 2,507 8,709 28 December 1,603 7,760 120 Yearly 144,750 1,093,553 21,640 --- Page 25 --- «93 Table 2. Rio Grande at El Paso, Texas Extreme Flow From Records: Maximum 24,000 second-feet on June 12, 1905, with a gage height of 6.0 feet at the lower gage. Minimum occasionally no flow. Since Elephant Butte Dam was closed in 1915, the largest peak flow to pass this station was 13,500 second-feet on September 3, 1925. Average Flow in Second-Feet Daily: Max. 23,680 June 12, 1905 Minimum 0 Occasionally Monthly: Max. 14,300 June 1905 Minimum 0 Occasionally Yearly: Max. 2,780 1905 Minimum 70.1 1902 Average Flow Period 1924-1954 Acre-Feet Average Maximum Minimum January 10,277 17,500 3,250 February 16,758 52,200 2,010 March 37,381 62,500 5,470 April 61,220 139,000 22,700 May 69,076 357,000 12,700 June 71,165 304,000 12,500 July 77,855 198,000 16,200 August 80,292 158,000 11,700 September 58,465 171,000 2,430 October 23,667 57,900 3,790 November 15,515 29,500 540 December 14,580 27,700 . 435 Yearly 536,251 1,559,200 93,725 --- Page 26 --- «= Dlex Table 3. Rio Grande at Island Station Extreme Flow From Records: Momentary: Maximum 6,490 second-feet on May 19, 1942, with a gage height of 16.06 feet. Minimum frequently no flow. Average Flow in Second Feet Daily: Maximum 6,140 May 19, 1942 Minimum 0 Frequently Monthly: Maximum 4,880 May 1942 Minimum 0 Several months 1951, 1953, and 1954 Yearly: Maximum 1,490 1942 Minimum 7.9 1952 Average Flow Period September 1938-1954 Acre-Feet Average Maximum Minimum January 7,549 11,900 2,020.0 February 5,831 37,000 161.0 March 3,931 21 ,000 20.2 April 7,182 70,500 5.0 May 21,236 299, 800 1.4 June 17,950 241,000 0.0 July 13,790 118,500 0.0 August 12,699 99,400 277.0 September 14,758 119,200 0.0 October 6,668 42,800 0.0 November 1,581 7,270 0.0 December 3,063 .. 12,900 0.0 . Yearly 116,238 1,079,340 5,708.5 During 97 days there was flow of water. --- Page 27 --- = 25+ Table 4. Rio Grande at Fort Quitman Extreme Flow From Records: Momentary: Maximum 10,600 second-feet on October 5, 1946, with a gage height of 10,000 feet. Minimum frequently no flow. Average Flow in Second Feet Daily: Maximum 5,890 May 19, 1942 Minimum 0) Frequently Monthly: Maximum 5,030 May 1942 Minimum 0 April and May, 1952 Yearly: Maximum 1,750 1942 Minimum 15.3 1952 Average Flow Period 1938-1954 Acre Feet Average Maximum Minimum January 11,778 20,900 165.0 February 11,674 50,100 164.0 March 9,674 38,900 670.0 April 12,019 77,000 0.0 May 21,812 309,000 20.2 June 19,859 240,000 973.0 July 20,682 140,000 185.0 August 25,443 127,000 108.0 September 28,680 147,000 51.6 October 21,222 66,500 67.6 November 13,650 24,500 43.2 December 14,131 31,000 Yearly 210,624 1,270,400 11,129.0 There was a daily discharge in second-feet of water for 345 days --- Page 28 --- -26- Table 5. Rio Grande at County Line Station Extreme Flow From Records: Momentary: Maximun 6,340 second~feet on May 19, 1942,with a gage height of 8.66 feet. Minimum frequently no flow. Average Flow in Second-Feet Daily: Maximum 6,180 May 18, 1942 Minimum 0.0 Frequently Monthly: Maximum 4,920 May 1942 Minimum 0.0 Frequently Yearly: Maximun 1,720 1942 Minimum 25 1952 and 1954 Average Flow Period 1938-1954 Acre Feet Average Maximum Minimum January 11,646 20,000 0 February 10,059 47,900 0 March 8,818 38,900 @) April 13,343 84 , 200 0 May 25,719 303,000 0 June 22,719 239,000 0) July 20, 834 140,000 ) August 19,909 123,000 0 September 22,754 140,000 0 October 15,173 61,400 ) November : 10,252 20,400 6) December 11,293 29,700 0 Yearly 192,519 1,247,500 347.5 There were 362 days of daily discharge. --- Page 29 --- Table 6. Rio Grande at Upper Presidio Station Extreme Flow From Records: Momentary: Maximum 14,000 second-feet on June 14, 1905. A gage height of 10.57 feet was recorded on May 26, 1942, with a flow of 5,160 second-feet. This level was the highest reached during the years 1923- 1954, inclusive. Minimum frequently no flow. Average Flow in Second-Feet Daily: Maximum 13, 700 June 13 and 14, 1905 Mimimum O Frequently Manthly: Maximum 10,150 June 1905 Minimum O Frequently Yearly: Maximum 1,970 1905 Minimum 0 1953 Average Flow Period 1924-1954 Acre Feet Average Maximum Minimum January 10,979 24,400 0.0 February 10,169 40, 800 0.0 March 8,059 39,100 0.0 April 6,631 41,600 0.0 May 15,892 240,000 0.0 June 15,628 216,000 218.0 July 21,590 158,000 13.1 August 27,970 133,000 120.0 September 31,168 151,000 0.0 October: 26,713 105,000 0.0 Nowember 12,787 34,500 0.0 December 12,422 30,900 0.0 Yearly 200,008 1,176,700 9,085.0 There were 129 days daily discharge of water. --- Page 30 --- -28- Table 7. Rio Concho River near Okinaga, Chihuahua Extreme Flow From Records: Momentary: Maximum 162,000 second~feet on Sept- ember 11, 1904. Minimum no flow several days in May, June, July, 1953. Average Flow in Second-Feet Daily: Maximum 148,900 September 11, 1904 Minimum 0.0 Several days 1953 Monthly: Maximum 23,540 September 1904 Minimum 11.0 May, 1902 Yearly: Maximum 3,720 1914 Minimum 155.0 1953 Average Flow Period 1924-1954 Acre Feet Average Maximum Minimum January 53,877 147,000 11,500 February 47,358 87,700 10,600 March 42,134 80, 800 5,410 April 28,228 79,700 855 May 33,991 148,000 1,560 June 39,975 91,900 760 July 88,188 502,000 8,890 August 118,531 601,000 7,660 September 233,922 1,173,000 6,770 October 144,138 798,000 5,890 November 56,395 110,000 9,510 December 48,895 97,700 9,940 Yearly 935,532 2,431,850 111,885 --- Page 31 --- . -29- Table 8. Rio Grande at lower Presidio station Extreme Flow From Records: Momentary: Maximum 162,000 second-feet on September 11, 1904. Minimim 0 occasionally in 1953. Average Flow in Second-Feet Daily: Maximum 149,200 September 11, 1904 Minimum -l May 10, 1953 Monthly: Maximum 24,870 September 1904 Minimum 7.8 April 1953 Yearly: Maximum 4,870 1906 Minimum 163.0 1953 Average Flow Period 1924-1954 Acre Feet Average Maximum Minimum January 64,945 164,000 11,600 February 57,425 99,700 10,700 March 50,150 89,400 5,400 April 34,303 84,100 464 May 49,608 270,000 1,760 June 55,313 267,000 4,540 July 109,062 564,000 8,910 August 146,174 675,000 10,200 September 265,141 1,324,000 7,370 October 170,966 864,000 6,050 November 69,252 141,000 9,510 December 61,365 116,000 9,940 Yearly 1,133,704 3,466,700 117,734 --- Page 32 --- «30 Table 9. Water quality data for the Rio Grande near Anthony, El Paso County September 1957 thru November 1959 Station Dates of Collection of Samples 22ers 3} URG=7 9757..10/15 10/29 12/3 1/3 i/i7y. o/& 2/20 3 3721 n H ‘ LT 79 78 7.9 8.0 8.0 7.9 7.8 7.5 7-8 7.8 Tor.SOL. tea a 1410 1596 2850 3120 4200 080 612 510 519 630 CHLORIDE 48 92 280 152 620 700 920 ©6980 90 60 56 60 SULPHATE 253 455 850 675 925 763 1200 1225 136 251 «2h5 | ahT CL. DEM. 1.8 1.8 9 0.9 0.9 0.9 0.9 3.5 1.8 0.5 0.5 25 D.0. 4.8 6.1 74 9.0 8.3 8.5 ToT 5°6 5.3 6.2 7-0 5-6 B.O.D. 0.5 25 1.6 0.5 1.0 1.0 2.7 0.5 1.6 0.5 204. 65 Station . Near Anthon Dates of Collection of Samples ' Bridge US 80 1958 URG= 5/2. 5/15 73 16 7/1 T/1 / 1 pH 7.0 7.7 7.0 109 8.0 7.0 8.0 7.9 ToT,SOL. 498 510 630 543 540 516 542 «4528 CHLORIDE 52 60 70 68 68 6h 68 64. SULPHATE 230 343 216 216 205 238 229 ~=64.90 CL. DEM. 0.5 0.9 365 0.5 27 0.9 0.5 0.5 D.O. 8 4b 48 5.03 5..0 3.2 4.6 3.9 ic: ny A: ls my | 0 0) aL wl 0 : 6 . TOT.SOL. 522 hee 1230 1350 sho 1380 1500 1476 1500 1500 P 1770 CHLORIDE 80 92 100 210 20 260 300 260 260 260 Hig 300 SULPHATE 248 180 375 420 420 500 525 480 480 500 Y 480 CL.DEM. 0.5 0.9 1.8 0.5 0.5 1.8 0.9 1.8 0.9 267 0.9 D.O0. 0.3 6.4 5.9 6.9 5.5 8.5 9.3 10.0 7.3 6.0 G3 B.O.D. 1: 7..035 1] 1.6 0.5 0.5 1.0 2.5 1.6 1.2 Station Same Dates of Collection of Samples Bridge US 80 1959 URG=7 3710 3/23. 4/6 E71 576 5/21 o/h 0/19 7/1 7/13 8/6 8/18 pH 7-2 9 Te. 77 7-7 To 7-7 E T. 7-7 ToT ToT TOT.SOL. 460 417 540 591 570 615 564 P 528 580 581 585 CHLORIDE 60 60 72 76 72 120 76 T 68 76 82 72 SULPHATE 193 185 200 200 220 230 200 Y 195 210 230 20 CL. DEM. @.7 0.5 1.8 0.5 8.3 …