TPWD 1964 F-5-R-11 #939: Fisheries Investigations and Surveys of the Waters of Region 1-B: An Investigation of Waters of the El Paso Area in Order to Evolve Efficient Management of the Game Fi

JOB COMPLETION REPORT As required by FEDERAL AID IN FISHERIES RESTORATION ACT TEXAS Federal Aid Project No. F-S-Rell FISHERIES INVESTIGATIONS AND SURVEYS OF THE WATERS 0F REGION l-B Job No. 3-34 An Investigation of Waters of the El Paso Area in Order to Evolve Efficient Management of the Game Fish Resource . Project Leader: Lawrence S. Campbell J. Weldon Watson Executive Director Parks and Wildlife Department Austin, Texas Marion Toole Eugene A. Walker DeJ Coordinator Assistant Direetor, Wildlife August 27, 1964 ABSTRACT General surveys and observations were conducted on more than 350 miles of canals and laterals, approximately 100 miles of the Rio Grande, and 8 secondary lakes. Detailed surveys were conducted on more than 400 miles of drainage canals, 50 miles of the Rio Grande, and 6 primary lakes. Data collected included physical topography of structures, chemistry of the water, and biological data pertaining to (a) vegetation type and distribution, (b) presence, influence, and distribution of amphibians, reptiles, birds, and mammals, and (d) presence, distribution, relative abundance, condition, reproductive success, and utilization of existing fish populations. Seventy-six rotenone collections made from 14,295 yards of drains resulted in taking 6,394 fish of 14 species. Forty-six gill net collections made in the Rio Grande resulted in the capture of 148 fish of 7 species. Seventy gill net collections from 5 lakes produced 1,422 fish of 12 species. Seining collections at lakes yielded another 3,125 specimens of 7 Species. Further studies were made to determine inherent problems associated with the area, and determined man—made circumstances or limitations imposed upon the present fish producing facilities. It was concluded that present knowledge is insufficient to provide adequate means for effectuating a substantial and long term improvement in game fish production in the Rio Grande and associated irrigation system. It is doubtful if further biological studies will provide the means of achieving a wide scale improvement in production by these facilities. The productive capacity of most of the system will continue to deteriorate. The Rio Grande and irrigation system should be employed in a secondary role in management attempted. Lakes and reser— voirs offer the best potential for producing game fish in the El Paso area, and their expansion should be encouraged. Present management of lakes and reservoirs is adequate. Large scale biological investigations should be suspended until the prospects of developing additional facilities or altering existing facilities are known. When circumstances will permit, investigations of this nature should be carried out. JOB COMPLETION REPORT State of Texas Project No. F-5mR-ll Name: Fisheries Investigations and Surveys of thg Waters of Region le Job No. B-34 Title: An investigation of Waters of the El Paso Area in Order to Evolve an Efficient Management of the Game Fish Resource ; Period Covered March 1, 1963 - February 28, 1964 Objectives: To obtain data essential to sound fisheries management of waters of the El Paso area. To obtain (a) physical, chemical, and biological data for determining the potential fishery resource, (b) data that will establish species present, distribution, relative abundance, condition, reproductive success, and utilization and (c) to determine the man-made circumstances and limitations imposed upon the present fish producing facilities. 3 Procedures: The field work, collection and treatment of data and the original rough draft of this report was accomplished by Assistant Project Leader Glenn Omundson. During this period of study Mr. Omundson and his crew of two biology field workers were stationed at El Paso. Because of an unexpected termination of employment with the Parks and Wildlife Department, as well as other circumstances beyond his con- trol, Mr. Omundson was unable to complete the final draft. Therefore, the field- collected data and the original rough draft was submitted to Project Leader Larry S. Campbell who revised the manuscript, completed and submitted the report in the final form. In surveying the Rio Grande and lakes and reservoirs of the El Paso area, 100 standard gill net collections, 39 Specific gill net collections, 24 standard seining collections, and 9 specific seining collections were taken. Data from these collections and basic data were recorded in accordance with the following project standards. I. Sampling Fish POpulations A. A standard gill netting unit is made up of nylon gill netting, measuring 150 feet long by 8 feet deep. The unit is in 25-foot sections. Mesh sizes of these nets increase progressively to larger sizes in following sections, at half-inch intervals, beginning with one—inch mesh sections and terminating with a three and one-half inch section. Bags are created in these nets by means of ”tie downs” that are 6 feet long and are spaced at 9-foot intervals along the horizontal length of the net. B. ,A standard gill net collection is the data from fish captured in an overnight set of one standard gill netting unit. II. C. A standard seining unit is a 12-foot common seine whose mesh size does not exceed 1/4 inch. D. A standard seining collection is data from fish captured with three hauls of a standard seining unit. E. A specific gill netting unit is any gill net, either with all its mesh the same size or with several sizes whose total components equal 150 linear feet. Data obtained from use of such nets is presented separately from that obtained from standard units. F. A specific gill net collection is the data from fish captured in an overnight set of a specific gill netting unit. G. A specific seining unit is any seining equipment that does not meet standard specifications. H. A specific seining collection is data from fish captured with a Specific seining unit. I. Data from gill netting collections normally included obtaining weight, length, sex and gonadal development, stomach contents, and ”K” for 50 individuals for each of the primary species. J. Data obtained from seining collections was in accordance with the objective for carrying out the work. Basic Data Recorded for Each Field Trip A. Physical data 1. Turbidity readings to denote major deviations in turbidity. 2. Temperatures (Fahrenheit). a. Water temperatures including area deviations and diurnal and nocturnal variations. b. Air temperatures including minimum and maximum for period during which field activities were carried out. 3. Wind (mph) a. Estimated speed, direction and variations. 4. Hydrology a. Lake or stream level or volume. b. Flow or velocity. 5. Weather and Climatic conditions a Cloud cover. b Moisture. c. Relative stability of temperatures. d Barometric pressure. e Moon phase. 6. Bottom type 7. Cover 8. Vegetation 9. Other ecological conditions or influences and observations. Occurrence of springs, stream gradient, shade of trees, canyon walls, riffles or falls, aquatic vegetation or organisms. B. Water Quality 1. Where possible data were obtained from qualified cooperating agencies. Most data were obtained from the State Health De“ partment, the U. S. Department of Agriculture, U. S. Salinity Laboratory, U. S. Department of the Interior, International Boundary and Water Commission, and the City of El Paso Water Department. 2. Essential determination of pH, dissolved oxygen, dissolved carbon dioxide, chlorides, and alkalinity were by standard analysis outlined in FRESHWATER FISHERY BIOLOGY by Lagler. As anticipated in planning, seining and netting proved to be ineffective for sampling fish populations of the irrigation canal system. In attempting to survey the supply canal system adequate sampling methods were not discovered. Flow, when water was present, was too great to permit effective sampling with gill nets or seines. The shallowness and velocity of the current, the deep mud of the bottom, and floating and suspended debris combined to render efforts to use nets ineffectual. It was equally impossible to sample fish populations of the supply system with chemicals. The effect of the chemical could not be adequately con— trolled, and fish destroyed could not be recovered in a manner to provide mean- ful data. A small isolated pool at the end of the Riverside Canal provided the only collection to sample fish populations for the supply canal system. In the drainage canal system other methods were tried and chemical sampling with rotenone was selected as the best technique for carrying out objectives. The procedure most frequently used was to place two 25-foot bag seines at Opposite ends of a measure length of canal (175w225 yards), and kill the entrapped fiSh with rotenone. As many fish were recovered as possible, tallies by species were made, and other data recorded in keeping with standards Specified for netting and seining collections. In rotenone collections toxicant was applied in two ways. If flow was meager or indolent the area between the two seines was treated with a Slurry of rotenone that was broadcast over nearly the entire surface of the closed off area. If velocity or flow was significant, (exceeding 2.5 - 3.0 mph), 3 thin slurry was mixed and introduced into the current about 10 yards above the upper net. Slow, gradual, and relatively uniform application was achieved by placing the slurry in a burlap bag for dissipation by the current in the sampling area. Trial and error determined the quantity of 6.5 per cent rotenone required to accomplish sampling of the limited area without serious damage to downstream pOpulations. Comparative results of seining and rotenone collections taken from the same site on succeeding days are shown in Table l. Table 1. Comparison of Two Sampling Methods in Anthony Drainage Canal Seining Collection Rotenone Sample Taken 5-8-63 Taken 5-9-63 Species Number Number __ Gizzard shad 16 221 Grey redhorse suckers 0 6 Carp 0 23 Channel catfish 1 0 Black bullhead O 9 Largemouth bass 1 0 Green sunfish 2 21 20 280 Seventy-six rotenone collections were taken from the drainage canal system. A summation of sampling efforts for the drainage system is as follows: Table 2. Composite for Mesilla, El Paso and Lower Valley Drainage Systems Total number of yards of canal worked 14,295 Total surface area (sq. ft.) 348,870 (acres) 8.01 Total volume (ft.3) 538,860 (acre—feet) 12.37 Number collections 76 Average Yards for Each collection 188 a. Work com leted in the Mesilla Valle U er Valle Total number of yards of canal worked 1,250 Total surface area (sq. ft.) 32,400 (acreS) .744 Total volume (ft 3) 54,000 (acre-feet) 1.24 Number collections 7 Average yards for each collection 178.6 b. Work Completed for El Paso Valley and Hudspeth County (Lower Valley} Total number of yards of canal worked 13,045 Total surface area (sq. ft.) 316,470 (acres) 7.266 Total volume (ft.3) 484,860 (acre-feet) 11.13 Number collections 69 Average yards for each collection 189.0 Work completed was much greater than that Specified in planning. Results: Background Information Probably, El Paso has greater need for expansion of the fishery resource than does any part of the state. Over 314,000 persons reside in El Paso County, 267,687 of them in the city. This urban population makes the area the most heavily populated locality in the western half of the state. There are no large Texas reservoirs within 100 miles of the city. Previous investigations have resulted in successful management of Lake Ascarate, and have determined some of the attributes of the Rio Grande and of the canal system. A study of flood retention structures in the McNary area indicated possible development of those facilities for recreation. Other details of previous work are to be found in job completion reports B*15, Project F-5-R-8; B—14, Project F-5-R-3; l6a29, Project F—l4-D-4; and 15a-11, Project F—l5-D-2. The Irrigation Canal System Waters of the Rio Grande are impounded in reservoirs in New Mexico and released on demand to downstream locations to be diverted into a maze of irrigation canals and laterals. These structures tranSport water for full irrigation of 178,000 acres. Of this quantity 70,000 acres are irrigated in the Mesilla and El Paso Valleys and supplemental irrigation is provided for 18,330 acres in Hudspeth County. The study carried out under this job included investigations of approximately 90 miles of primary canals, 270 miles of secondary laterals, and nearly 457 miles of drainage canals. Descriptions of Component Parts of the Irrigation System Primary canals supply bulk water throughout the valley to farms and ranches where it is siphoned or released into laterals for final dissipation in fields. These canals average approximately 25 feet at the tOp and 20 feet at the bottom. Maximum carrying capacity is at 5-foot depth. The cross-section of the larger canals approximates an inverted trapezoid. Sides of canals are capped with grasses, primarily bermuda and St. Augustine, but lower portions are generally bare. Canal bottoms are covered with fine to medium sand or mud. Several larger canals as the Riverside Canal and the Franklin Canal exceed these dimensions. Laterals are usually 3 feet to 5 feet at the top and from 1 foot to 2 feet deep. Their cross-section approximates a ”U”, although a few cementnlined laterals more closely resemble an inverted trapezoid. A few of the major laterals as La Union Lateral, Montoya Lateral and San Elizario Lateral greatly exceed these descriptions. Drainage canals have three functions. (1) Excess water supplied to fields from the canal system is removed through drains, (2) seepage and ground water is returned to the supply system or to the Rio Grande, and (3) flushing action of top soils removed excessive concentrations of harmful salts and these sus~ pended materials are transported by drains and emptied into the Rio Grande. With few exceptions, drains maintain flow the year around. Water is supplied directly to the drain system under the auspices of the Bureau of Reclamation from various dams and flood retainer structures located in New Mexico and Colorado, and sub- surface flow and seepage supply drains. Due to an extended period of drouth being experienced within the Upper Rio Grande drainage area, particularly in northern New Mexico and Colorado, water storage for the Bureau's Rio Grande Project has been decreasing for more than 10 years. Should this trend continue, disasterous effects on aquatic life can be expected. Drains are from 15 to 40 feet wide at the t0p and from 5 to 25 feet wide at the bottom. Average depth is 8 to 10 feet. Water rarely exceeds an average depth of 2 feet. The topography and ecology of drains is kept in a constant state of flux due to alterations in water quality and a continuous program of repair and maintenance. Repeated maintenance is necessary to control rapidly growing salt cedar, accumulations of mud and silt, and erosion of banks and adjacent fields. Drain classification would range from recently renovated to mature. The renovated drains are barren and devoid of vegetation, both on the Sides and bottom, and lack salt cedars. If these drains are allowed to stand unattended for some time, growths of grasses, primarily bermuda, cattails (Typha Sp.) and filamentous algae appear in and along drains. These growths are supplemented within one year with growths of salt cedar which appear at the crown and descend the banks of drains. Within three or four years, drains have matured and are characterized by debris-filled mud bottom. When mature, drains support luxuriant growth of filamentous algae and cattails. Sides are covered with grass and salt cedar. The top of banks are crowned with salt cedar. The Rio Grande is a functioning part of the irrigation system for 73 miles. Stream flow is jointly controlled by the U. S. Bureau of Reclamation and the Department of Interior of Mexico. Levees are maintained on both sides of the river at specific heights, widths, and distance from the channel. These have been established and maintained primarily as flood control measures, but ultie mately serve to make the river into a tremendous canal. Within El Paso's city limits, gates extending across the river can divert its flow into the Franklin Canal for irrigation purposes. During the irrigation period the river below these diverting structures dries up and remains dry until water is drained back into the channel in Hudspeth County. During the remainder of the year, the river may or may not carry water, depending on municipal requirements and releases from a series of dams Operated by the Bureau of Reclamation. It is the rule rather than the exception to find the riverbed dry for several consecutive months during the non-irrigation season. Normal flow descends and.becomes sub- surface before entering the city limits and does not emerge until it reaches Hudspeth County. Maps of various subdivisions of the irrigation system are given in Figures 3 through 12. For a complete map of the system these segments may be removed and joined together beginning with Figure 3 and continuing in the order of their appearance through Figure 12. Figure 1. Typical canal structure that releases flow into laterals or drainage canals Figure 2. Typical canal during period when water is being released. .oanewo>mm one cofiuospOHm swam snow was xuflfimsw HoumB muons hoHHm> noon: otH .m onswflm