General Background:

While an undergraduate at the University of Pittsburgh, I was hired as a summer research assistant with CMNH's Division of Education. That led to a protracted volunteer internship, beginning in 1978, with the bird-banding program at Powdermill Nature Reserve, under the direction of Robert C. Leberman. I was hired in 1983 as a full-time staff member of the Section of Birds to assist with the bird-banding program, to conduct other field studies in ornithology, and, also, to serve as an environmental education specialist developing public programs and interpretive materials for the newly constructed Florence Lockhart Nimick Nature Center at Powdermill. Since 1992, I have worked exclusively with bird-banding and other field ornithology research and education projects at Powdermill.

Research Interests (numbers correspond to references below):

• Avian Life History Studies ^{1, 2, 3, 4}
• Passerine Molts and Plumages ^{6, 7, 8, 13}
• Passerine Flight Morphology ^{9, 10, 14, 15, 17, 18}
• Patterns of Avian Survivorship ^{5, 12}
• Avifaunal Studies of Pennsylvania Birds ^{11, 19}
• Differential Migration Timing ^{15, 16}
• Nesting and Foraging Ecology of Louisiana Waterthrushes ^{1, 2, 4}

References (reprints of many of these are available upon request):

1. Mulvihill, R. S., M. K. Girvan, E. R. Franklin, T. L. Master, T. J. O'Connell, and R. P. Brooks. [in review]. Chronology of nesting, molting, and migration of Louisiana Waterthrushes in Pennsylvania, with special reference to double brooding. Condor.

2. Mulvihill, R. S., A. Cunkelman, L. Quattrini, T. J. O'Connell, and T. L. Master. [in review]. Rare occurrences of polygyny in the Louisiana Waterthrush: possible causes, costs, and constraints. Wilson Bulletin.

3. Sánchez, J. E., R. S. Mulvihill, and T. L. Master. 2000. First description of the nest and eggs of the Green-crowned Brilliant (Heliodoxa jacula), with some behavioral notes. Ornitologia Neotropical 11:189-195.

4. Mulvihill, R. S. 1999. Effects of stream acidification on the breeding biology of an obligate riparian songbird, the Louisiana Waterthrush (Seiurus motacilla). Pp. 51-61 in The effects of acidic deposition on aquatic ecosystems in Pennsylvania (W. E. Sharpe and J. R. Drohan, eds.). Proc. 1998 PA Acidic Deposition Conf., Vol. 2, Environmental Resources Research Institute, University Park, PA.

5. Mulvihill, R. S., & R. C. Leberman. 1997. Factors affecting the survival of Ovenbirds wintering in the Northeast. Wilson Bulletin 109:161-166.

6. Mulvihill, R. S., & C. Rimmer. 1997. Timing and extent of the molts of adult Red-eyed Vireos (Vireo olivaceus) on their breeding and wintering grounds. Condor 99:73-82.

7. Mulvihill, R. S., & R. L. Winstead. 1997. Variation in the extent of the first prebasic molt of Dark-eyed Juncos. Journal of Field Ornithology 68:183-199.

8. Mulvihill, R. S. 1993. Using wing molt to age passerines. North American Bird Bander 18:1-10.

9. Mulvihill, R. S. 1993. Interspecific analysis of wing shape variation in selected wood warblers (Aves: Parulinae). M.S. thesis, Indiana University of Pennsylvania, 115 pp.

10. Chandler, C. R., & R. S. Mulvihill. 1992. Effects of age, sex, and fat level on wing loading in Dark-eyed Juncos. Auk 109:235-241.

11. Mulvihill, R. S. 1992. [20 different species accounts]. In Atlas of breeding birds in Pennsylvania (D. W. Brauning, ed.), Univ. of PIttsburgh Press, Pittsburgh, PA.

12. Mulvihill, R. S., R. C. Leberman, & D. S. Wood. 1992. A possible relationship between reversed sexual size dimorphism and reduced male survivorship in the Ruby-throated Hummingbird (Archilochus colubris). Condor 94:480-489.

13. Mulvihill, R. S., K. C. Parkes, R. C. Leberman, & D. S. Wood. 1992. Evidence supporting a dietary basis for orange-tipped rectrices in the Cedar Waxwing. Journal of Field Ornithology 63:212-216.

14. Mulvihill, R. S., & C. R. Chandler. 1991. A comparison of wing shape between migratory and sedentary Dark-eyed Juncos (Junco hyemalis). Condor 93:172-175.

15. Chandler, C. R., & R. S. Mulvihill. 1990. Wing-shape variation and differential timing of migration in Dark-eyed Juncos. Condor 92:54-61.

16. Chandler, C. R., & R. S. Mulvihill. 1990. Interpreting differential timing of capture of sex classes during spring migration. Journal of Field Ornithology 61:85-89.

17. Mulvihill, R. S., & C. R. Chandler. 1990. The relationship between wing shape and differential migration in the Dark-eyed Junco. Auk 107:490-499.

18. Chandler, C. R., & R. S. Mulvihill. 1988. Wing shape indices: An evaluation. Ornis Scandinavica 19:212-216.

19. Mulvihill, R. S. 1988. The occurrence of Dickcissels (Spiza americana) in western Pennsylvania-Its possible bearing on the species' unusual history in eastern North America. Pennsylvania Birds 2:83-87.

Current Research:
At Powdermill Nature Reserve, differences in stream quality between unpolluted Powdermill Run and acidified Laurel Run adjacent to it have provided an excellent opportunity to study the possible effects of acid mine drainage pollution (AMD) of headwater streams on the demographics, behavioral ecology, productivity, and survivorship of populations of an obligate riparian songbird, the Louisiana Waterthrush (Seiurus motacilla; LOWA).

The LOWA feeds mostly on aquatic macroinvertebrates, many of which cannot survive or reproduce in acid-polluted streams. Powdermill Run is a pH-neutral stream, has abundant macroinvertebrates, and supports diverse fish populations. Laurel Run, which is impacted by drainage from two abandoned coal mines, is acidic (pH 4.0-5.0), with high levels of dissolved aluminum and iron, has reduced macroinvertebrate diversity and density, and supports no fish.

Studies were begun in 1996 to determine whether or not pollution of Laurel Run affects the breeding density, reproductive success, foraging behavior, and/or survivorship of Louisiana Waterthrushes by reducing the diversity, abundance, and/or biomass of invertebrate prey available to them during the breeding season. Preliminary results of the study showed that the number of territories, pairing success, and nesting densities of LOWAs nesting along the acidified stream were lower. In the first year, we found only four territories and 50% pairing success in Laurel Run compared to 11 territories and 91% pairing success for the same reach length of Powdermill Run (see Mulvihill, R. S., 1997, The Louisiana Waterthrush and Our Mountain Streams, Carnegie Magazine May/June:62-65). Our initial results have been amplified by results for these streams in subsequent years. Laurel Run has never had more than four nesting pairs and Powdermill Run has never had fewer than eight pairs in the last five years (click here to see nesting density map, 1996-2000).

The study was continued in 1997 with partial funding from Pennsylvania's Wild Resource Conservation Fund (WRCF). At the end of 1997, two sources of AMD on Laurel Run were partially remediated using passive treatment technologies (see Gangewere, R. J., 1998, Saving Our Mountain Streams, Carnegie Magazine January/February:8-12, 36-39). Funding from WRCF for fieldwork in 1998 enabled us to continue to monitor changes in the Laurel Run LOWA and macroinvertebrate populations in response to anticipated improvement in stream quality resulting from these treatments. Additional funding for the LOWA study in 1999 and 2000 came from the Loyalhanna Watershed Association and the Rea Research Fund of Carnegie Musuem of Natural History.

Remediation of Laurel Run is ongoing, with additional treatment projects planned for 2001, and before long we expect to see LOWA numbers there increase to levels similar to those observed on Laurel's unimpacted sister stream, Powdermill Run, signalling that the ecological balance of this picturesque stream has been substantially restored after more than 50 years of degradation.

An extension of the LOWA study at Powdermill has been a collaborative study with Dr. Robert P. Brooks, Penn State Cooperative Wetlands Center and Dr. Terry Master, East Stroudsburg University, to develop a calibrated index of regional ecological integrity for forested headwater streams using bioindicators. This study compares Louisiana Waterthrush populations, avian riparian communities, and aquatic macroinvertebrate communities between pristine forested headwater streams and streams impacted by acid pollution and/or forest fragmentation in the mountains of southwestern, central, and eastern Pennsylvania (23 study streams in all). Funding was received for this project (see our progress reports online) from the U.S. Environmental Protection Agency (EPA) for three years (1998-2000). Results of this study regarding the impacts of stream acidification echo those of the Powdermill study. Results of this study have been reported at numerous professional meetings, including the 1999 American Ornithologists Union meeting at Cornell University, the 2000 Wilson Ornithological Society meeting at Galveston, the 2000 AOU meeting at Memorial University in St. John's Newfoundland, and the 2000 Waterbird Society meeting at Plymouth, Massachusetts. A final report, as well as numerous manuscripts detailing various aspects of this study will be completed during 2001.

Memberships and Professional Service:

• North American Banding Council
  Official Trainer
  Education Committee
  
• Pennsylvania Biological Survey
  Ornithological Technical Commitee
  Species Status Subcommittee
  Important Bird Areas Subcommittee