Aquatic macroinvertebrate inventory & assessment of springs and seeps within Bighorn Canyon National Recreation Area (BICA)
By: prepared for the: Western National Parks Association and the Greater Yellowstone Network Inventory & Monitoring Program, National Park Service ; by: David M. Stagliano
Contributors: Montana Natural Heritage Program; Western National Parks Association; Greater Yellowstone Inventory and Monitoring Network (U.S.)
Published: 2008
Language: eng
Number of pages: 18
Subjects: Inventory control; Aquatic invertebrates; Water quality biological assessment; Environmental indicators
Description: Spring ecosystems in arid regions are oftentimes  the only permanent water source in the uplands  and provide essential habitat for  a myriad of aquatic and terrestrial organisms (Erman 2002); they  are essentially aquatic islands in a sea of desert  (Thompson et al 2002)  . Riparian areas adjacent to  springs can provide habitat to up to 75% of the available species diversity in arid regions (Shepard  1993). Spring ecosystems have evolved within a narrow set of environmental conditions strictly dependent on groundwater discharge (Shepard 19  93). Discharge of springs within Bighorn  Canyon National Recreation Area (BICA) has been  found to be dependent on snowmelt-based  groundwater reaching outflows as recently as weeks after melting, to as  long as years after (D.  Schmitz, pers. comm.). The mosaic of microhabitats  in springs is largely  due to stable, long-term  flow rates (Perla & Stevens 2003),  and perennial discharg  e has been linked to diverse, unique and  often endemic flora and fauna  (Myers 1995, Sada and Vinyard 2002). Aquatic macroinvertebrates  can make up a substantial proportion of spring biodiversity. Aquatic species in spring ecosystems  can display a high degree of endemism, often evolving to subtle cues in water chemistry (Arsufi  1993, Heino et al. 2003; Sada et al  . 2005). Macroinvertebrate populations in springs of the Great  Basin, Sierra Nevada, and Colorado Plat  eau are known to support endemic aquatic macroinvertebrates (Erman 2002; Hershler and Sa  da 2002; Sada and Herbst 2001). An initial  survey of Great Basin Springs reported four new  species of aquatic invertebrates (Myers 1995). A  new species of the springsnail,  Pyrgalopsis  (the only species reported east of the continental  divide) has recently been found in a Missouri River (Montana) spring (Hershler and Gustafson  2002). Even though most spring locations in BICA  have been documented on USGS topographic  maps, there has been no documentation of aquatic fauna occurring within these ecosystems.  Spring flora and fauna in BICA  have only been investigated for  occurrence of rare riparian and  wetland plants (ex.Sullivantia  hapemanii var. hapemanii) (Heidel and Fertig 2000).  Therefore, a survey of spring fauna  will substantially increase the  known BICA species and document  potentially rare, endemic or endangered species. Surveys in this  area will fill data gaps, serve as a  reference point for change  detection, provide a baseline  necessary for evaluating the rarity of different spring ecosystem types,  and form an understanding o  biological diversity and integrity at the local and ecoregional level. Many spring species have narrow environmental ranges (specialists) and therefore are susceptible to changes in water chemistry and habitat quality Our main objectives for this study include 1) an  initial aquatic invertebrate faunal survey and  bioassessment of targeted perennial BICA springs, 2) determining  the environmental factors that  determine biointegprovide a sampling scheme and  identify indicator measures (species richness, abundance, target species (i.e. endemics, etc.) with which to monitor spring diversity and biointegrity in the future.  Achieving our objectives, especially  the third, will allow park managers to monitor the status and  changes of aquatic macroinvertebrate indicators  over time within BICA springs. This process can  be repeated every five years for any proposed spring-type monitoring protocol: an impaired (cattle or human impacted) sample and a reference (pristine) condition sample from each spring type
Notes: "March 2008"

Cover title.

Includes bibliographical references (page 14).
Table of contents: title: Introduction; title: Methods; title: Results; title: Discussion; title: Conclusions and Recommendations; title: Literature Cited.