Prepared in cooperation with the National Park Service and Amistad National Recreation Area Water Quality and the Composition of Fish and Macroinvertebrate Communities in the Devils and Pecos Rivers In and Upstream from the Amistad National Recreation Area, Texas, 2005–7 Scientific Investigations Report 2012–5038 U.S. Department of the Interior U.S. Geological Survey Cover Left. Dolan Falls on the Devils River, Texas. Cover Right. Photo was taken where the International Boundary and Water Commission (IBWC) gaging station near Langtry is located. The wier dam where the gage sensor is located is in the picture. Water Quality and the Composition of Fish and Macroinvertebrate Communities in the Devils and Pecos Rivers In and Upstream from the Amistad National Recreation Area, Texas, 2005–7 By J. Bruce Moring Prepared in cooperation with the National Park Service and Amistad National Recreation Area Scientific Investigations Report 2012–5038 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2012 This and other USGS information products are available at http://store.usgs.gov/ U.S. Geological Survey Box 25286, Denver Federal Center Denver, CO 80225 To learn about the USGS and its information products visit http://www.usgs.gov/ 1-888-ASK-USGS Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Moring, J.B., 2012, Water quality and the composition of fish and macroinvertebrate communities in the Devils and Pecos Rivers in and upstream from the Amistad National Recreation Area, Texas, 2005-7: U.S. Geological Survey Scientific Investigations Report 2012–5038, 70 p. iii Contents Abstract .......................................................................................................................................................1 Introduction.....................................................................................................................................................2 Purpose and Scope .............................................................................................................................4 Description of Study Area ...................................................................................................................4 Methods of Investigation ..............................................................................................................................5 Collection and Analysis of Water-Quality Samples.........................................................................6 Collection and Processing of Fish and Macroinvertebrate Samples ..........................................7 Fish Community Surveys and Processing of Samples ....................................................................8 Macroinvertebrate Community Surveys and Processing of Samples .........................................8 Quality Control .......................................................................................................................................8 Water Quality in the Devils and Pecos Rivers ......................................................................................30 Total Dissolved Solids ........................................................................................................................30 Chloride.................................................................................................................................................30 Sulfate ..................................................................................................................................................30 Ammonia Plus Organic Nitrogen ......................................................................................................30 Nitrate Plus Nitrite Nitrogen .............................................................................................................33 Orthophosphate and Total Phosphorus ...........................................................................................33 Selenium ...............................................................................................................................................33 Pesticides .............................................................................................................................................33 Composition of Fish and Macroinvertebrate Communities in the Devils and Pecos Rivers ......................................................................................................33 Fish Communities ................................................................................................................................34 Devils River .................................................................................................................................34 Pecos River .................................................................................................................................34 Comparison between the Devils and Pecos Rivers ...................................................34 Macroinvertebrate Communities .....................................................................................................42 Summary .......................................................................................................................................................63 References ....................................................................................................................................................67 Appendix 1. Laboratory recovery of surrogate compounds from four sets analyzed concurrently with water-quality samples from U.S. Geological Survey stations 08449400 Devils River at Pafford Crossing near Comstock, Texas, and 08447410 Pecos River near Langtry, Tex., in the Amistad National Recreation Area, 2005 ................70 iv Figures 1. Map showing location of study area .......................................................................................3 2. Graph showing assessment of similarities among fish communities determined by using Non-metric Multi-Dimensional Scaling (first and second dimensions) for fish collected in 2006-7 at the Devils and Pecos Rivers sites in and upstream from the Amistad National Recreation Area, Texas ..................................................................................................................................43 3. Graph showing assessment of similarities among macroinvertebrate communities determined by using Non-metric Multi-Dimensional Scaling (first and second dimensions) for aquatic insects collected in 2006 from sampling sites on the Devils and Pecos Rivers in and upstream from the Amistad National Recreation Area, Texas ............................................................................64 Tables 1. Sample-collection sites on the Devils and Pecos Rivers in and upstream from the Amistad National Recreation Area, Texas, 2005–07 ...............................................6 2. Concentrations of total dissolved solids, selected major ions, and nutrients in water-quality samples collected at U.S. Geological Survey stations 08449400 Devils River at Pafford Crossing near Comstock, Texas, and 08447410 Pecos River near Langtry, Tex., in the Amistad National Recreation Area, Tex., 2005............................................................................................................................10 3. Concentrations of trace metals in water-quality samples collected at U.S. Geological Survey stations 08449400 Devils River at Pafford Crossing near Comstock, Texas and 08447410 Pecos River near Langtry, Tex., in the Amistad National Recreation Area, Tex., 2005 .......................................................................12 4. Concentrations of organic carbon and pesticides in water-quality samples collected at U.S. Geological Survey stations 08449400 Devils River at Pafford Crossing near Comstock, Texas, and 08447410 Pecos River near Langtry, Tex., in the Amistad National Recreation Area, Tex., 2005 ...........................................................14 5. Concentrations of selected major ions and nutrients measured in water-quality samples collected in 2005 at U.S. Geological Survey stations 08449400 Devils River at Pafford Crossing near Comstock, Texas, and 08447410 Pecos River near Langtry, Tex., in the Amistad National Recreation Area, with summary statistics from samples collected at station 08449400 during 1978–1995 as part of the U.S. Geological Survey Hydrologic Benchmark Network (U.S. Geological Survey, 2011), and summary statistics from samples collected at station 08447410 during 1974–2007 as part of U.S. Geological Survey National Stream Quality Accounting Network (U.S. Geological Survey, 2010)..................................................................................31 v 6. Presence or absence of fish taxa and total number of fish species collected from sites on the Devils and Pecos Rivers in and upstream from the Amistad National Recreation Area, Texas, 2006–7 ...............................................................................35 7. Fish species, number of individual specimens, native status, trophic group, tolerance