GEOLOGICAL SURVEY OF ALABAMA Berry H. (Nick) Tew, Jr. State Geologist ECOSYSTEMS INVESTIGATIONS PROGRAM CALIBRATION OF THE INDEX OF BIOTIC INTEGRITY FOR THE TENNESSEE VALLEY ICHTHYOREGION IN ALABAMA OPEN-FILE REPORT 1004 by Patrick E. O'Neil and Thomas E. Shepard Prepared in cooperation with the Alabama Department of Environmental Management and the Alabama Department of Conservation and Natural Resources Tuscaloosa, Alabama 2010 TABLE OF CONTENTS Abstract ............................................................ 1 Introduction.......................................................... 1 Acknowledgments .................................................... 6 Objectives........................................................... 7 Study area .......................................................... 7 Tennessee Valley ichthyoregion .................................... 7 Methods ............................................................ 9 IBI sample collection ............................................. 9 Habitat measures............................................... 11 Habitat metrics ........................................... 12 The human disturbance gradient ................................... 16 IBI metrics and scoring criteria..................................... 20 Designation of guilds....................................... 21 Results and discussion................................................ 23 Sampling sites and collection results . 23 Selection and scoring of Tennessee Valley IBI metrics . 41 Metrics selected for the Tennessee Valley IBI . 47 1. Number of native species ................................. 47 2. Number of shiner species ................................ 48 3. Number of sucker species................................. 48 4. Number of darter + madtom species . 51 5. Number of intolerant species .............................. 51 6. Proportion as tolerant species.............................. 54 7. Proportion as Lepomis ................................... 54 8. Proportion as invertivores ................................. 58 9. Proportion as omnivores and herbivores . 58 10. Proportion as top carnivores .............................. 61 11. Proportion with DELT+hybrids . 61 12. Number of lithophilic spawning species . 63 IBI development for the Tennessee Valley ichthyoregion . 63 Conclusions ........................................................ 81 References cited..................................................... 83 Appendix A. Habitat evaluation forms..................................... 88 Appendix B. Reproduction and trophic guild classifications for Alabama fishes . 91 Appendix C. Tennessee Valley ichthyoregion fish community sampling data . 103 TABLES Table 1. IBI sampling sites in the Tennessee Valley and Plateau ichthyoregions, 2008-09 ...................................................... 25 Table 2. Fish species collected in the Tennessee and Black Warrior River systems ...................................................... 29 Table 3. Rapid habitat assessment scores for sites in the Tennessee Valley and Plateau ichthyoregions........................................... 34 ii Table 4. Human disturbance metrics for sites in the Tennessee Valley and Plateau ichthyoregions ................................................. 37 Table 5. LDI-weighted human disturbance metrics for sites in the Tennessee Valley and Plateau ichthyoregions.................................. 39 Table 6. Correlation coefficients between candidate IBI metrics and habitat assessment metrics ............................................. 42 Table 7. Correlation coefficients between candidate IBI metrics and human disturbance metrics ............................................. 43 Table 8. Statistical and responsive measures for candidate IBI metrics . 44 Table 9. Redundancy analysis for Tennessee Valley ichthyoregion IBI metrics . 46 Table 10. Fish community values for Tennessee Valley IBI metrics . 66 Table 11. Scores for Tennessee Valley IBI metrics . 69 Table 12. IBI integrity classes for the Ridge & Valley/Piedmont, Southern Plains, and Tennessee Valley ichthyoregions . 72 FIGURES Figure 1. Preliminary ichthyoregion classification for Alabama . 5 Figure 2. Ecoregions and river systems in Alabama . 8 Figure 3. Conceptual model illustrating the relationship between disturbance, stressor, and response. .......................................... 17 Figure 4. Location of IBI sampling sites in the Tennessee and Black Warrior River systems ................................................. 24 Figure 5. Frequency distribution of sampling sites by watershed area and human disturbance ................................................... 28 Figure 6. Relationships between the IBI metric number of native species and watershed area, disturbance, and habitat. 49 Figure 7. Relationships between the IBI metric number of shiner species and watershed area, disturbance, and habitat . 50 Figure 8. Relationships between the IBI metric number of sucker species and watershed area, disturbance, and habitat . 52 Figure 9. Relationships between the IBI metric number of darter+madtom species and watershed area, disturbance, and habitat . 53 Figure 10. Relationships between the IBI metric number of intolerant species and watershed area, disturbance, and habitat . 55 Figure 11. Relationships between the IBI metric percent tolerant species and watershed area, disturbance, and habitat . 56 Figure 12. Relationships between the IBI metric percent Lepomis and watershed area, disturbance, and habitat ..................................... 57 Figure 13. Relationships between the IBI metric percent invertivores and watershed area, disturbance, and habitat. .................................... 59 Figure 14. Relationships between the IBI metric percent omnivores and herbivores and watershed area, disturbance, and habitat . 60 Figure 15. Relationships between the IBI metric percent top carnivores and watershed area, disturbance, and habitat . 62 iii Figure 16. Relationships between the IBI metric percent DELT + hybrids and watershed area, disturbance, and habitat . 64 Figure 17. Relationships between the IBI metric number of lithophilic spawners and watershed area, disturbance, and habitat . 65 Figure 18. Frequency distribution of IBI integrity classes for sites in the Tennessee Valley ichthyoregion............................................. 72 Figure 19. Comparison of the IBI in level III ecoregions relative to habitat quality and a comparison of IBI scores for small and large watersheds relative to habitat quality.................................................. 73 Figure 20. Comparison of the IBI in level III ecoregions relative to human disturbance and a comparison of IBI scores for small and large watersheds relative to human disturbance ..................................... 75 Figure 21. Comparison of the IBI relative to habitat quality for level IV ecoregions in the Tennessee Valley ichthyoregion . 76 Figure 22. Comparison of the IBI relative to human disturbance for level IV ecoregions in the Tennessee Valley ichthyoregion . 77 Figure 23. Tiered aquatic life use relationships between the IBI, habitat quality, and human disturbance for sites in the Tennessee Valley ichthyoregion . 79 Figure 24. Biological condition gradient models for the Tennessee Valley ichthyoregion .................................................. 80 iv ABSTRACT The Tennessee Valley ichthyoregion in north Alabama was sampled from May through October 2009 to develop data for creating and calibrating the Index of Biotic Integrity (IBI). Ninety-seven sampling sites were selected to represent a range of watershed areas and levels of human disturbance. Watersheds ranged in area from 1.76 square miles (mi22) to 308 mi with 45 percent of the watersheds <20 mi2, 42 percent ranging from 21 to100 mi22, and 11 percent were >100 mi . Rapid habitat assessments were completed for each sample and eight measures of human disturbance were derived for each site from a geographic information system. Thirty- four candidate IBI metrics were screened for inclusion in the IBI by evaluating their relationship to the habitat assessment and human disturbance metrics. Both human disturbance metrics and habitat metrics were correlated with IBI metrics. Twelve metrics were selected for the Tennessee Valley IBI: number of native species, number of shiner species, number of sucker species, number of darter+madtom species, number of intolerant species, proportion of tolerant species, proportion of Lepomis species, proportion of invertivores, proportion of omnivores and herbivores, proportion of top carnivores, proportion with DELT+hybrids (DELT=deformities, eroded fins, lesions, tumors) and number of lithophilic spawning species. The IBI was effective in discriminating sites with good habitat scores from sites with poor habitat scores. Thirty- two percent of the sites scored in the poor to very poor range, 40 percent in the fair range, and 28 percent in the good to excellent range. The Tennessee Valley IBI scoring criteria were adjusted slightly lower than criteria developed for the Ridge & Valley/Piedmont and Southern Plains ichthyoregions. The Tennessee Valley IBI integrity classes were applied to the USEPA biological condition gradient concept for tiered aquatic life uses to model the response of biological condition to ecosystem stress in the region. This model can be used to better assess stream aquatic life use in Tennessee Valley streams and provide an additional tool for screening streams for