Moniana Slate Library 3 0864 1003 0509 6 BIOLOGICAL INTEGRITY OF BEAVER CREEK IN THE BIG SPRING CREEK TMDL PLANNING AREA BASED ON THE STRUCTURE AND COMPOSITION OF THE BENTHIC ALGAE COMMUNITY Prepared for: State of [Montana Department of Environmental Quality P.O. Box 200901 Helena, Montana 59620-0901 Project Officer: Rebecca Ridenour DEQ Contract No. 200012-10 Prepared by: Loren L. Bahls, Ph.D. Hannaea 1032 Twelfth Avenue Helena, Montana 59601 July 21, 2004 ST/nt DOCUMENTS COLLECTl AUG 2 3 2004 MONTANA STATE UIBR/-' 1S15 E. 6th AVE. HELENA MONTANA 59620 Pruned on paper mmiefrom 100% recycled post-consumer fiber Summary In July 2003, periphyton samples were collected from three sites on Beaver Creek in the Big Spring Creek TMDL planning area in central Montana to assess whether this stream is water-quality limited and in need of TMDLs. The Beaver Creek samples were collected following MDEQ standard operating procedures, processed and analyzed using standard methods for periphyton, and evaluated following modified USEPA rapid bioassessment protocols for wadeable streams. Samples of conspicuous macroscopic algae were also collected from Casino Creek and Cottonwood Creek in July 2003 to identify the taxa responsible for these growths. Results are reported here and in a memo dated October 9, 2003. These samples were not collected following MDEQ standard operating procedures. The upper site on Beaver Creek was moderately impaired by sedimentation and provided less than full support for aquatic life uses. The pollution index was depressed at the upper site, suggesting minor impairment from organic loading. The lower site was also moderately impaired by sedimentation, but the pollution index here was just above the threshold for minor impairment. The middle site had the best biological integrity of the three sites on Beaver Creek. Diatom metrics indicate only minor disturbance and minor impairment from sedimentation here. The eutraphentic diatom Gomphonema minutum was a dominant species at both the middle and lower sites, indicating elevated concentrations of inorganic nutrients at both sites. The green alga Cladophora ranked second in biomass at these two sites. The algal specimen collected from Casino Creek was a large colony o^ Cladophora, probably Cladophora glomerala. Cladophora is a common mat-forming filamentous green alga that often becomes a nuisance in nutrient-rich waters around the world. The bright green color indicates fresh new growth, that is, epiphytic diatoms had not yet had a chance to colonize the filaments. The algal specimen collected from Cottonwood Creek proved to be a colony of diatom cells embedded in amorphous mucilage. The cells were mainly a Cymbella species and a Synedra species. These taxa are known to extrude polysaccharide mucilage through pores in their cell walls, thus forming stalks, tubes, and amorphous masses in which the diatoms live. Certain species of Cymbella and Synedra are associated with eutrophication. Introduction This report evaluates the biological integrity', support of aquatic life uses, and probable causes of stress or impairment to aquatic communities in Beaver Creek, located in the Big Spring Creek TMDL planning area of central Montana. The main purpose of this report is to provide information that will help the State of Montana determine whether Beaver Creek is water-quality limited and in need of TMDLs. This report also describes conspicuous algal growths collected from nearby Casino Creek and Cottonwood Creek. The federal Clean Water Act directs states to develop water pollution control plans (Total Maximum Daily Loads or TMDLs) that set limits on pollution loading to v/ater-quality limited waters. Water-quality limited waters are lakes and stream segments that do not meet water- quality standards, that is, that do not flilly support their beneficial uses. The Clean Water Act and USEPA regulations require each state to (1) identify waters that are water-quality limited, (2) prioritize and target waters for TMDLs, and (3) develop TMDL plans to attain and maintain water-quality standards for all water-quality limited waters. Evaluation of aquatic life use support in this report is based on the species composition and structure of periphyton (benthic algae, phytobenthos) communities at stream sites that were sampled in July 2003. Periphyton is a diverse assortment of simple photosynthetic organisms called algae that live attached to or in close proximity of the stream bottom. Some algae form long filaments or large colonies and are conspicuous to the unaided eye. But most, including the ubiquitous diatoms, can be seen and identified only with the aid of a microscope. The periphyton community is a basic biological component of all aquatic ecosystems. Periphyton accounts for much of the primary production and biological diversity in Montana streams (Bahls et al. 1992). Plaflcin et al. (1989) and Barbour et al. (1999) list several advantages of using periphyton in biological assessments. ' Biological integrity is defined as "the ability of an aquatic ecosystem to support and maintain a balanced, integrated, adaptive community of organisms having a species composition, diversity, and functional organization comparable to that of natural habitats within a region" (Karr and Dudley 1981). Project Area and Sampling Sites The project area is located in Fergus County in central Montana. Beaver Creek, Casino Creek, and Cottonwood Creek are tributaries of Big Spring Creek, which is a principal tributary of the Judith River. These streams head south of Lewistown on the north side of the Big Snowy Mountains, which is an outlier of the Middle Rockies Ecoregion (USEPA 2000). Periphyton samples were collected at three sites on Beaver Creek (Table 1). Elevations at the sampling sites range from about 4400 feet above mean sea level at the upper site to about 3840 feet at the lower site. Vegetation in the study area is mainly mixed conifer forest in the upper reaches of Beaver Creek and mixed grassland along the middle and lower reaches (USDA 1976). Land use is primarily livestock grazing. Samples of conspicuous algae were also collected from nearby Casino Creek and Cottonwood Creek (Table 1). Methods Periphyton samples were collected from Beaver Creek following standard operating procedures of the MDEQ Planning, Prevention, and Assistance Division. Using appropriate tools, microalgae were scraped, bnished, or sucked from natural substrates in proportion to the importance of those substrates at each study site. Macroalgae were picked by hand in proportion to their abundance at the site. All collections of microalgae and macroalgae were pooled into a common container and preserved with Lugol's (IKI) solution. Grab samples of conspicuous macroalgae (for identification only) were collected from Casino Creek and Cottonwood Creek and preserved with Lugol's solution. The Beaver Creek samples were examined to estimate the relative abundance and rank by biovolume of diatoms and genera of soft (non-diatom) algae according to the method described in Bahls (1993). Soft algae were identified using Smith (1950), Prescott (1962, 1978), John et al. (2002), and Wehr and Sheath (2003). These books also served as references on the ecology of the soft algae, along with Palmer (1969, 1977). After the identification of soft algae, the raw periph>ton samples were cleaned of organic matter using sulfuric acid, postassium dichromate, and 3% hydrogen peroxide. Then, permanent diatom slides were prepared using Naphrax, a high refractive index mounting medium, following Standard Methods for the Examination of Water and Wastewater (APHA 1 998). Approximately 350 diatom cells (700 valves) were counted at random and identified to species. The following were the main taxonomic references for the diatoms: Krammer and Lange-Bertalot 1986, 1988, 1991a, 1991b; Lange-Bertalot 2001; Krammer 2002. Diatom naming conventions followed those adopted by the Academy of Natural Sciences for USGS NAWQA samples (Morales and Potapova 2000). Van Dam et al. (1994) was the main ecological reference for the diatoms. The diatom proportional counts were used to generate an array of diatom association metrics. A metric is a characteristic of the biota that changes in some predictable way with increased human influence (Barbour et al. 1999). Diatoms are particularly useful in generating metrics because there is a wealth of information available in the literature regarding the pollution tolerances and water quality preferences of common diatom species (e.g., Lowe 1974, Beaver 1981, Lange-Bertalot 1996, Van Dam et al. 1994). Values for selected metrics were compared to biocriteria (numeric thresholds) developed for streams in the Rocky Mountain ecoregions of Montana (Table 2). These criteria are based on the distribution of metric values measured in least-impaired reference streams (Bahls et al. 1992) and metric values measured in streams that are known to be impaired by various sources and causes of pollution (Bahls 1993). The biocriteria in Table 2 are valid only for samples collected during the summer field season (June 21 -September 21). The criteria in Table 2 distinguish among four levels of stress or impairment and three levels of aquatic Ufe use support: (1) no impairment or only minor impairment (full support); (2) moderate impairment (partial support); and (3) severe impairment (nonsupport). These impairment levels correspond to excellent, good, fair, and poor biological integrity, respectively. Quality Assurance Several steps were taken to assure that the study results are accurate and reproducible. Upon receipt of the samples, station and sample attribute data were recorded in the Montana Diatom Database and the samples were assigned a unique number, e.g., 3045-01. The first part of this number (2951) designates the sampling site (Beaver Creek near mouth) and the second part (01) designates the number of periphyton samples that that have been collected at this site for which data have been entered into the Montana Diatom Database. Sample observations and analyses of soft (non-diatom) algae were recorded in a lab notebook along with information on the sample label. A portion of the raw sample was used to make duplicate diatom slides. The slide used for the diatom proportional count will be deposited in the Montana Diatom Collection at the University of Montana Herbarium in Missoula. The duplicate slide will be retained by Hannaea in Helena. Diatom proportional counts have been entered into the Montana Diatom Database. Results and Discussion Results are presented in Tables 3, 4 and 5, which are located near the end of this report following the references section. Appendix A consists of a series of diatom reports, one for each sample. Each diatom report contains an alphabetical list of diatom species and their percent abundances, and values for 65 different diatom metrics and ecological attributes. Sample Notes Beaver Creek. All three samples from Beaver Creek were putrid, but the algae were still intact and identifiable. The samples from the upper and lower sites were extremely silty and the sample from the middle site was very silty. The sample from the middle site consisted mostly of detritus. Cladophora was present but senescent at all three sites. Casino Creek. Macroscopically, the specimen in this sample appeared as a large bright green mass of filamentous algae. Microscopically, the mass proved to be a monoculture of Cladophora, probably Cladophora glomerata, a common filamentous green alga (Division Chlorophyta) that often becomes a nuisance in nutrient-rich lakes and streams in temperate regions around the world. The bright green color indicates fresh new growth; epiphytic diatoms had not yet had a chance to colonize the filaments. Cottonwood Creek. Macroscopically, the specimen in this sample appeared as a pale yellow to beige flocculent mass about 1 centimeter thick and several centimeters wide and long. Microscopically, the mass proved to be a colony of diatom (Division Bacillariophyta) cells embedded in amorphous mucilage. The cells were mainly a Cymbella species and a Synedra species. These taxa are known to extrude polysaccharide mucilage through pores in their cell walls, thus forming stalks, tubes, and amorphous masses in which the diatoms live. Certain species of Cymbella and Synedra are associated with eutrophication. Non-Diatom Algae (Beaver Creek) In addition to diatoms, which ranked first in biovolume at all three sites, periphyton samples fi-om Beaver Creek contained cyanobacteria, red algae, green algae, and yellow-green algae (Table 3). At the upper site, the pollution-tolerant cyanobacterium Oscillatoha was fi-equent and ranked 2"'' in biovolume. The filamentous green alga Cladophora was common and ranked 3"^ , while the filamentous red alga Audouinella was occasional and ranked 4'*^. At the middle site, Cladophora and Oscillatoria were common and frequent and ranked 2" and 3"^ , respectively, followed in abundance by Vaiicheria and two genera of green algae: Oedogonium and Closterium. The chrysophyte Vaucheria prefers steady flows of cool water and is often found in springs and spring brooks. At the lower site, Cladophora was abundant and ranked 2" in biovolume, followed by an occasional cell of Closterium, which ranked 3"^. Cladophora is frequently cited as an aquatic nuisance in the United States (Wehr and Sheath 2003). Large standing crops of Cladophora are of^en a sign of elevated concentrafions of inorganic nutrients, particularly phosphorus. Diatoms (Table 4) Six of the major diatom species in Beaver Creek are sensitive to organic pollution and these were abundant at all three sites (Table 4). Six of the major species are somewhat tolerant of organic pollution and these were present at all three sites. Nitzschia linearis, a somewhat tolerant species that is also highly motile and tolerant of sedimentation, was abundant only at the upper site. Only one of the major diatom species— Nitzschia palea — is most tolerant of organic pollution (pollution tolerance class 1). Nitzschia palea was most abundant at the upstream site and declined in relative abundance at the middle and lower sites (Table 4). Diatom metrics suggest the upper site was moderately impaired by sedimentation and provided less than full support for aquatic life uses. This was due to a much larger than normal percentage of motile diatoms, which approached the threshold for severe impairment in a mountain stream. The pollution index was also depressed at the upper site, suggesting minor impairment from organic loading (Table 4). Nitzschia palea, a nitrogen heterotroph, was the second most abundant diatom species here. Otherwise, diatom species richness and diversity at this site were acceptable, and no abnormal diatom cells were recorded. The middle site had the best biological integrity of the three sites on Beaver Creek. Diatom metrics indicate only minor impairment from sedimentation and minor disturbance due to the slightly elevated percentage of Achnanthidium minutissimum. The second most abundant species here was Gomphonema minutum, an eutraphentic species that suggests elevated levels of inorganic nutrients (Van Dam et al. 1994). Two abnormal diatom cells were recorded at this site, which is normal background. This site shared about half of its diatom assemblage with the upper site, indicating only minor changes in envirormiental conditions. A large percentage of motile diatoms suggests the lower site was moderately impaired by sedimentation. G. minutum was the dominant diatom species here, indicating eutrophication. The pollution index approached but did not drop below the threshold for minor impairment. No abnormal diatom cells were observed and species richness and diversity were acceptable but on the low side. This site shared about half of its diatom assemblage with the middle site. Several ecological attributes were selected from the diatom reports in the appendix and modal categories of these attributes were extracted to characterize water quality tendencies at the three sites (Table 5). The majority of diatoms at all three sites were freshwater nitrogen autotrophs that tolerate only a small amount of BOD loading. Nitrogen autotrophs require inorganic nitrogen (nitrates and ammonia) as nutrients. Most of the diatoms at the middle site were non motile, suggesting that this site had the least amount of sedimentation. On the other hand, the largest motility category at the upper site was "highly motile" and the largest category at the lower site was "moderately motile". The sedimentation index indicated moderate impairment at both of these sites. The largest trophic state category at the upper site was "variable". Diatoms in this category tolerate a wide range of concentrations of inorganic nutrients. At the middle and lower sites, most diatoms were in the "eutraphentic" category, which suggests that concentrations of inorganic nutrients (carbon, nitrogen, and phosphorus) were elevated at these sites. Most diatoms at the middle site belong to the "circumneutral" pH category. These diatoms prefer pH levels around 7. At the upper and lower sites, the largest pH category was "alkaliphilous", which suggests higher pH values and perhaps more photosynthesis (primary production) at these sites. The modal category for dissolved oxygen demand was "continuously high" at the upper and middle sites. The largest category for dissolved oxygen demand at the lower site was "not classified". References APHA. 1998. Standard Methods for the Examination of Water and Wastewater. 20'* Edition. American Public Health Association, Washington, D.C. Bahls, L.L. 1979. Benthic diatom diversity as a measure of water quality. Proceedings of the Montana Academy of Sciences 38:1-6. i Bahls, L.L. 1993. Penphyton Bioassessment Methods for Montana Streams (revised). Montana Department of Health and Environmental Sciences, Helena. Bahls, L.L. , Bob Bukantis, and Steve Tralles. 1992. Benchmark Biology of Montana Reference Streams. Montana Department of Health and Environmental Sciences, Helena. Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. 1999. Rapid Bioassessment Protocols for Use In Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish. Second Edition. EP.A841-B-99-002. U.S. Environmental Protection Agency, Office of Water, Washington, D.C. Beaver, Janet. 1981. Apparent Ecological Characteristics of Some Common Freshwater Diatoms. Ontario Ministry of The Environment, Technical Support Section, Don Mills, Ontario. Johansen, J.R. 1999. Diatoms of Aerial Habitats. Chapter 12 ;n Stoermer, E.F., and J.P. Smol (eds.). The Diatoms: Applications For the Environmental and Earth Sciences, Cambridge University Press, New York. John, D.M., B.A. Whitton, and A.J. Brook (eds.). 2002. The Freshwater .Mgal Flora of the British Isles: An Identification Guide to Freshwater and Terrestrial Algae. Cambridge University Karr, J.R., and D.R. Dudley. 1981 . Ecological perspectives on water quality goals. Environmental Management 5:55-69. Krammer, Kurt. 2002. Cymbella. Volume 3 in Diatoms of Europe, Horst Lange-Bertalot, ed. A.R.G. Gantner Verlag K.G., Germany. Krammer, K., and H. Lange-Bertalot. 1986. Bacillariophyceae, Part 2, Volume 1: Naviculaceae. In Ettl, H., J Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, New York. Krammer, K., and H. Lange-Bertalot. 1988. Bacillariophyceae, Part 2, Volume 2: Bacillariaceae, Epithemiaceae, Surirellaceae. In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, New York. Krammer, K., and H. Lange-Bertalot. 1991a. Bacillariophyceae, Part 2, Volume 3: Centrales, Fragilariaceae, Eunotiaceae. In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, Stuttgart. Krammer, K., and H. Lange-Bertalot. 1991b. Bacillariophyceae, Part 2, Volume 4: Achnanthaceae, Critical Supplement to Navicula (Lineolatae) and Gomphonema, Complete List of Literature for Volumes 1-4. In Ettl, H., G. Gartner, J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, Stuttgart. Lange-Bertalot, Horst. 1979. Pollution tolerance of diatoms as a criterion for water quality estimation. Nova Hedwigia 64:285-304. 10 Lange-Bertalot, Horst. 1996. Rote Liste der limnischen Kieselalgen (Bacillariophyceae) Deutschlands. Schr.-R. f. Vegetationskde., H. 28, pp. 633-677. BfN, Bonn-Bad Godesberg. Lange-Bertalot, Horst. 2001 . Navicula sensu stricto: 10 Genera Separated from Navicula sensu lata; Frustulia. Volume 2 in Diatoms of Europe, Horst Lange-Bertalot, ed. A.R.G. Ganmer Verlag KG., Germany. Lowe, R.L. 1974. Environmental Requirements and Pollution Tolerance of Freshwater Diatoms. EPA-670/4-74-005. U.S. Environmental Protection Agency, National Environmental Research Center, Office of Research and Development, Cincinnati, Ohio. ' McFarland, B.H., B.H. Hill, and W.T. Willingham. 1997. Abnormal Fragilaria spp. (Bacillariophyceae) In streams impacted by mine drainage. Journal of Freshwater Ecology 12(1):141-149. Morales, E.A., and Marina Potapova. 2000. Third NAWQ.A. Workshop on Harmonization of Algal Taxonomy, May 2000. Patrick Center for Environmental Research. The .\cademy of Natural Sciences, Philadelphia. Palmer, CM. 1969. A composite rating of algae tolerating organic pollution. Journal of Phycology 5:78-82. Palmer, CM. 1977. Algae and Water Pollution: An Illustrated Manual on the Identification, Significance, and Control of Algae in Water Supplies and m Polluted Water. EPA-600/9-77-036. Plafkin, J.L., M.T. Barbour, K.D. Porter, S.K. Gross, and R.M. Hughes. 1989. Rapid Bioassessment Protocols for Use in Rivers and Streams: Benthic Macroinvertebrates and Fish. EPA 440-4-89-001. Prescott, G.W. 1962. Algae of the Western Great Lakes Area. Wm. C Brown Coinpany, Dubuque, Iowa. Prescott, G.W. 1978. How to Know the Freshwater Algae. Third Edition. Wm. C Brown Company Publishers, Dubuque, Iowa. Renfro, H.B., and D.E. Feray. 1972. Geological Highway Map of the Northern Rocky Mountain Region. American Association of Petroleum Geologists, Tulsa, Oklahoma. Smith, G.M. 1950. The Fresh- Water .Algae of The United States. McGraw-Hill Book Company, New York. Stevenson, R.J., and Y. Pan. 1999. Assessing Environmental Conditions in Rivers and Streams with Diatoms. Chapter 2 in Stoermer, E.F., and J.P. Smol (eds.). The Diatoms: Applications For the Envirormiental and Earth Sciences, Cambridge University Press, New York. Stewart, W.D.P., P. Rowell, and A.N. Rai. 1980. Symbiotic Nitrogen-Fixing Cyanobacteria. Pp. 239-277 in Stewart, W.D.P., and J. Gallo (eds.). Nitrogen Fixation, Academic Press, New York. USD A. 1976. Climax Vegetation of Montana (map). U.S. Department of Agriculture, Soil Conservation Service, Cartographic Unit, Portland. USEPA. 2000. Level III Ecoregions of the Continental United States (map). U.S. Environmental Protection Agency, Corvallis, Oregon. Van Dam, Herman, Adrienne Mertens, and Jos Sinkeldam. 1994. A coded checklist and ecological Indicator values of freshwater diatoms from The Netherlands. Netherlands Journal of Aquatic Ecology 28(1): 1 17-133. Weber, CI. (ed.). 1973. Biological Field and Laboratory Methods for Measuring the Quality of Surface Waters and Effluents. EPA-670/4-73-001. U.S. Envnonmental Protection Agency, National Environmental Research Center, Office of Research and Development, Cincinnati, Ohio. 11 Wehr, J. D., and R.G. Sheath. 2003. Freshwater Algae of North America: Ecology and Classification. Academic Press, New York. Whittaker, R.H. 1952. A study of summer foliage insect communities in the Great Smoky Mountains. Ecological Monographs 22:1-44. Woods, A.S., Omemik, J.M., Nesser, J.A., Shelden, J., and S.H. Azevedo. 1999. Ecoregions of Montana (color poster with map), U.S. Geological Survey, Reston, Virginia. '■ 12 Table 1. Location of MDEQ periphyton sampling stations on Beaver, Casino, and Cottonwood Creeks. MDEQ Hannaea Sample Station Station Code Sample Number Latitude Longitude Date Beaver Creek at Regli (upper) Beaver Creek above county road (middle) Beaver Creek near mouth {lower) Casino Creek^ Cottonwood Creek below Glengarry M22BEVRC01 3044-01 M22BEVRC02 3043-01 M22BEVRC04 3045-01 M22CSNOC04 ^ 46 56 11 109 3109 7/23/2003 46 58 54 109 33 27 7/23/2003 47 04 46 109 35 56 7/24/2003 46 59 31 109 27 09 7/23/2003 M22CTWDC05 3090-01 47 02 24 109 32 41 7/23/2003 'These samples were collected only for the identification of conspicuous macroalgae and were not collected following MDEQ standard operating procedures. ^A diatom slide was not made from this sample, hence the sample was not assigned a number in the Montana Diatom Database. O) (/] QJ Q) g O 9? o QJ O) QJ o i- o !l3 to E o ro Mi 1— c Ol 5 C 3 ro o ^ E o c TO >. 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