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                                                      Stream Salamanders as Indicators of Stream Quality in Maryland
                                                                                                                                                                              Multivariable Analyses of Important Factors                                                                                                                                                                                               4. Creating the Index
   Introduction                                                                             Stream Salamander Sampling Sites                                                  • Land use – Percent forest (+), percent impervious surface (-), percent urban (-)
   Biological indicators are critical to the protection of small, headwater streams and                                                                                                                                                                                                                                                                                                                                 Stream Salamander Index of Biotic Integrity (SS-IBI) =
                                                                                                                                                                              • Physical Habitat – shading (+), gravel (-), riffle extent (+), riparian buffer width (+),
   the ecological values they provide. Maryland and other state monitoring programs
                                                                                                                                                                                aesthetic rating (+), total rocks (+), maximum depth (+), average thalweg depth (-)
   have determined that fish indicators are ineffective in small streams, where stream                                                                                                                                                                                                                                                                                                                                    Sum of Normalized Metric Scores Divided by the Number of Metrics (4)
                                                                                                                                                                              • Water Quality – ANC (-), DOC (+)
   salamanders may replace fish as top predators. Because of their life history,                                                                                                                                                                                                                                                                                                                                               -Number of Species
                                                                                                                                                                              • Biology – B-IBI (+), predator fish abundance (-)
   physiology, abundance, and ubiquity, stream salamanders are likely representative                                                                                                                                                                                                                                                                                                                                           -Number of Salamanders
   of biological integrity in these streams. The goal of this study was to determine                                                                                                                                                                                                                                                                                                                                           -Percentage of Adults
   whether stream salamanders are effective indicators of ecological conditions across
   biogeographic regions and gradients of human disturbance.
                                                                                                                                                                              Steps in Indicator Development                                                                                                                                                                                                                   -Percentage of Intolerants
                                                                                                                                                                              1.                      Identify Reference and Degraded Sites
                                                                                                                                                                                                                                                                                                                                                                                                                        Scores are assigned on a 0-10 scale, with a score of <5 the threshold for
                                                                                                                                                                              2.                      Partition Natural Variability
   Salamanders are Sensitive to Human Disturbance                                                                                                                                                                                                                                                                                                                                                                       degradation.
                                                                                                                                                                              3.                      Test Salamander Metrics
                                                                                                                                                                              4.                      Create the Index


                                                                                            Distribution of stream salamander sampling sites in the Non-Coastal Plain of
                                                                                            Maryland. Each site was also sampled for water chemistry, physical habitat, and
                                                                                                                                                                              1. Identifying Reference and Degraded Sites                                                                                                                                                                                                                                   6


                                                                                            other biological variables using MBSS methods.                                                        Reference sites must meet all of the following criteria:                                                                                                                                                                                                  2

                                                                                                                                                                                                   - F-IBI or B-IBI ≥ 4 (scale of 1 to 5)                                                                                                                                                                                                                   0

                                                                                                                                                                                                   - Forest land use ≥ 75%
                                                                                                                                                                                                   - Riparian buffer width ≥ 50 m                                                                                                                                                                                                                                Reference   Intermediate   Degraded

                                                                                            Stream Salamanders in Maryland                                                                         - Stream shading ≥ 50%
                                                                                                                                                                                                   - Aesthetic rating ≥ 10 (scale of 0 to 20)                                                                                                                                                                           Distribution of Non-Coastal Plain SS-IBI scores for 76 stream sites separated into
                                                                                                                                                                                                                                                                                                                                                                                                                        reference, intermediate, and degraded classes based on non-salamander criteria.
                                                                                                                                                                                                  Degraded sites must have B-IBI < 3 or F-IBI < 4 and any of the following:                                                                                                                                             Boxes describe the 75th, 50th, and 25th percentiles with dotted lines denoting means.
                                                                                                                                                                                                  - Forest land use ≤ 10%                                                                                                                                                                                               Whiskers describe 90th and 10th percentiles with dots denoting values outside the
                                                                                                                                                                                                  - Riparian buffer width ≤ 15 m                                                                                                                                                                                        range.
                                                                                                                                                                                                  - Stream shading ≤ 40%
   MBSS Provides Stressor Information at Each Site                                                                                                                                                - Aesthetic rating ≤ 5 (scale of 0 to 20)                                                                                                                                                                             Index Performance
   •   Samples 1,500 stream sites in each 5-year round
                                                                                                                                                                                                  After the thresholds for designating sites as reference and degraded were                                                                                                                                             Percentage of sites correctly classified by the SS-IBI:
   •   Uses probability-based design stratified on watershed and stream order
   •   Measures water chemistry, physical habitat, and biological communities                                                                                                                     applied, sites not meeting either threshold were classified as intermediate.                                                                                                                                             • Highland SS-IBI
   •   Developed reference-based indicators of integrity for fish, benthic invertebrates,                                                                                                                                                                                                                                                                                                                                       85% reference, 100% degraded, 88% combined
                                                                                                Northern Two-lined salamander        Long-tailed salamander                                                                                                                                          Geographic Region
       and physical habitat                                                                     Eurycea bislineata                   Eurycea l. longicauda                                                                                                                                                                                                                                                                  • Piedmont SS-IBI
                                                                                                                                                                                                                                      Condition                                                                                                                                                                                 100% reference, 75% degraded, 87% combined
                                                                                                                                                                                                                                                                                      Highlands                           Piedmont                      Non-Coastal
                                                                                                                                                                                                                                                                                                                                                           Plain                                                            • Non-Coastal Plain SS-IBI
   Fish Index of Biotic Integrity (F-IBI) is Not Rated for                                                                                                                                                                                                                                                                                                                                                                      88% reference, 93% degraded, 90% combined
                                                                                                                                                                                                                                    Reference                                              13                                  11                            24
   the Smallest Streams
                                                                                                                                                                                                                                    Intermediate                                           12                                  25                            37
                                                                                                                                                                                                                                                                                                                                                                                                                        Index Validation
                                                                                                                                                                                                                                    Degraded                                                3                                  12                            15                                                         Partial validation of these indices was obtained when a test of the number of
                                                                                                                                                                                                                                                                                                                                                                                                                        salamander species metric produced an 82% correct classification of 618 MBSS
                                                                                                                                                                                                                                    Total                                                  28                                  48                            76                                                         sites surveyed in MBSS Round One. Salamander abundances were not recorded at
                                                                                                                                                                                                                                                                                                                                                                                                                        these sites so the other metrics could not be calculated.
                                                                                            Allegheny Mountain dusky salamander      Northern dusky salamander
                                                                                            Desmognathus ochrophaeus                 Desmognathus fuscus
                                                                                                                                                                              2. Partitioning Natural Variability                                                                                                                                                                                                       • Small streams contribute to water quality and biodiversity but have
                                                                                                                                                                              Stream salamander communities differ slightly among the four physiographic                                                                                                                                                                  been historically overlooked
                                                                                                                                                                              regions west of the Coastal Plain in Maryland. Distribution maps show that D.                                                                                                                                                             • Stream salamanders are effective indicators of health in small streams
                                                                                                                                                                              monticola and D. ochrophaeus are not found in the Blue Ridge or Piedmont of                                                                                                                                                               • Stream salamander searches require a 10% increase in sampling
                                                                                                                                                                              Maryland, while P. montanus is not found in the Appalachia Plateau, Valley & Ridge,                                                                                                                                                         effort of MBSS
       Study Question                                                                       Seal salamander
                                                                                                                                                                              or Blue Ridge regions. The other five stream salamander species occur in all four
                                                                                                                                                                                                                                                                                                                                                                                                                        • SS-IBI provides a vertebrate indicator in streams too small for fish
       Can streamside salamanders effectively discriminate ecological condition in                                                                                            regions. Because of these species distribution differences, indicator development
                                                                                            Desmognathus monticola
       small streams across ecological regions and gradients of human disturbance?                                                                                            was conducted separately for the Highlands and Piedmont as well as for all sites
                                                                                                                                                                              combined (i.e., Non-Coastal Plain Maryland).
       Study Approach                                                                                                               Northern spring salamander
       - Piggyback on MBSS sites in Highlands and Piedmont during summer of 2001                                                    Gyrinophilus p. porphyriticus
       - Apply proven transect and quadrat sampling methods                                                                                                                                                                                                                                                                                                                                                                Mark Southerland1                                                    Robin Jung2
                                                                                                                                                                              3. Testing Salamander Metrics                                                                                                                                                                                                                David Baxter1                                                        Isaac Chellman2
                                                                                                                                                                              We tested 11 candidate salamander metrics to see if values were significantly
                                                                                                                                                                              different between reference and degraded sites:
                                                                                                                                                                                                                                                                                                                                                                                                                           Ginny Mercurio1
                                                                                                                                                                                  Measures of Species Richness and Composition: number of species,                                                                                                                                                                         Jon Vølstad1
                                                                                                                                                                                     numbers of D. fuscus, D. ochrophaeus, E. bislineata, and G. p. porphyriticus
                                                                                                                                                                                                                                                                                                                                                                                                                             1Versar,Inc.                                      2
                                                                                                                                                                                  Measures of Salamander Abundance: number of all salamanders                                                                                                                                                                                                                                   USGS Patuxent Wildlife Research Center
                                                                                                                                                                                                                                                                                                                                                                                                                              9200 Rumsey Road                                 12100 Beech Forest Road
                                                                                                                                                                                  Measures of Species Tolerance: number and percentage of intolerant                                                                                                                                                                          Columbia, MD 21045
                                                                                                                                                                                                                                                                                                                                                                                                                              410-964-9200                                     Laurel, MD 20708
                                                                                                                                                                                     salamanders (defined as all species except E. bislineata)
                                                                                                                                                                                  Measures of Reproductive Function: number of adults, number and
                                                                                            Eastern mud salamander                 Red salamander                                    percentage of larvae
                                                                                            Pseudotriton montanus                  Pseudotriton ruber                                                                                                                                                                                                                                                                   Acknowledgements
                                                                                                                                                                              Metric values received a discrete score (i.e., 0, 5, 10) based on comparison to the                                                                                                                                                       We would like to thank the stream salamander field crew that in addition to DPB and
                                                                                                                                                                              10th and 50th percentile of reference. “Reverse” metrics are scaled so that higher                                                                                                                                                        ICC included Jeff Tomlinson and Ed Schwartzman. We thank Ron Klauda and Paul
                                                                                                                                                                              values receive lower scores.
   Stream Salamander Indicator Study Components                                             Stream Salamander Data                                                                                          Number of Species                                              Number of Salamanders                                     Number of Adults                                Percentage of Intolerant Species
                                                                                                                                                                                                                                                                                                                                                                                                                        Kazyak of the MBSS and Erica Shingara of the City of Gaithersburg for permission
   • Sampled 76 streams with transects and quadrats at MBSS sites                           • Collected 1,584 stream salamanders                                                                                                                                                                                                                                                                                        to use the non-salamander data collected at the sites, and J. Andrew Royle, Jodi
                                                                                                                                                                                                  6                                                                 250                                                   60                                                   120

   • Removal samples on transects to determine salamander detection probabilities           • Mean of 21 salamanders and 2 species per site                                                       5
                                                                                                                                                                                                                                                                                                                          50                                                   100
                                                                                                                                                                                                                                                                                                                                                                                                                        Dew, and Allison Brindley for statistical and analytical support. We give special
                                                                                                                                                                                                                                                                                                                                                                                                                        thanks to MBSS crew leaders, Tony Prochaska and Matt Kline, for welcoming our
                                                                                                                                                                                                                                            Number of Salamanders


   • Multivariate analysis of 52 water quality, physical habitat, land use and biology
                                                                                                                                                                                                                                                                                                                          40                                                   80
                                                                                                                                                                              Number of Species

                                                                                              37% adults; 63% larvae

                                                                                                                                                                                                                                                                                                       Number of Adults

                                                                                                                                                                                                  3                                                                                                                       30                                                   60

     variables to identify factors affecting salamander distribution and abundance          • Eurycea bislineata at 88% of stream sites; comprised 75% of all salamanders                         2                                                                                                                       20                                                   40                                       salamander crew during their sampling. The funding for this research was provided
                                                                                                                                                                                                                                                                                                                                                                                                                        by the U.S. Geological Survey Amphibian Research and Monitoring Initiative (ARMI)
                                                                                                                                                                                                  1                                                                                                                       10                                                   20

   • Reference-based indicator development                                                    collected                                                                                           0                                                                                                                       0                                                     0

                                                                                            • Salamander detection probabilities ranged from 0.71 to 0.85                                               Reference        Degraded                                         Reference       Degraded                              Reference         Degraded                             Reference          Degraded
                                                                                                                                                                                                                                                                                                                                                                                                                        in the Northeast region.

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