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Co-sponsored Meeting Reports Dick Stern 1150 Linden Hall Rd. Boalsburg Pennsylvania 16827 Acoustics Today welcomes contributions for “Co-sponsored Meeting Reports” There is no charge for this service. Submissions of no more than 1000 words that may be edited in MSWord and up to two photos should be e-mailed to <AcousticsToday@aip.org>. ACOUSTIC COMMUNICATION BY ANIMALS SYMPOSIUM Mary Bates maryebates@gmail.com In August, researchers from disparate fields with a com- mon interest in animal bioacoustics met in Ithaca, N.Y., for the 3rd International Symposium on Acoustic Communication by Animals. The conference was hosted by Cornell University's Bioacoustics Research Program and sponsors included the Acoustical Society of America, Office of Naval Research, National Oceanic and Atmospheric Administration, and National Science Foundation. The meeting began with a keynote talk from Peter Narins of the University of California, Los Angeles. Narins discussed the concave-eared torrent frog, an unusual amphibian that makes its home at the base of Mt. Huangshan in Anhui Province, China. These animals were found living in an environment full of intense, broad spectrum ambient noise from the rushing creek and nearby waterfalls. Recordings of their calls revealed significant energy in the ultrasonic range, and examination of the frogs' anatomy showed a recessed tympanic membrane and a mammalian- like ear canal. It is likely these frogs faced selection pressure from their noisy habitat to increase the frequency of their calls and hearing to communicate effectively. In fact, Narins and his colleagues discovered another frog species in Borneo with similar ultrasonic vocalizations and a depressed tym- panic membrane. The two species are not closely related, sug- gesting they independently evolved those characteristics in response to similar environmental pressures. Narins' talk highlighted what would be a major theme of the meeting—noise and its effects on animal communica- tion. Rachele Malavasi of the University of Carlo Bo, Italy, presented data that revealed songbirds in stable communities coordinated their chorusing to avoid signal masking. Cornell University’s Aaron Rice analyzed automatic recordings of marine acoustic communities off the shore of the southeast- ern United States and found evidence for acoustic niche par- titioning between species that share acoustic space. These animals, and Narins' ultrasonic frogs, have adjusted or evolved solutions so they can still communicate amidst natu- rally occurring noise. For other animals, problems arise when the noise is anthropogenic. Sandra Blumenrath (University of Maryland, College Park) explained how reverberant environments com- promise detection and discrimination of communication sounds in songbird networks, and Jenelle Dowling (Cornell University) discussed how urban development results in structures with hard, impervious surfaces that, to wildlife, have unfamiliar absorptive and reflective properties. Other researchers are examining the effects of anthro- pogenic noise on marine mammals. Christopher Clark of Cornell presented analyses showing the acoustic footprint of large shipping vessels was enormous, effectively “bleaching” large areas of endangered right whale habitat and significant- ly limiting their communication opportunities. The conse- quences of perturbing an acoustic community are not fully understood, especially in harder-to-observe marine environ- ments. We currently do not know how shipping noise affects right whale movements and communication, but noise of this magnitude has the potential to interfere with foraging effi- ciency, mating opportunities, and possibly even survival. Leila Hatch (Stellwagen Bank National Marine Sanctuary) addressed the need for changes in the way we try to abate anthropogenic noise in the ocean. She put forward that current noise management focuses on short-term, tran- sient noise and has a heavy emphasis on marine mammals. Future noise management plans must pay attention to the cumulative noise footprints from multiple sources, consider ecologically relevant scales in both space and time, address chronic lower intensity noise sources, and include all wildlife (fish, invertebrates, etc.). Hatch called for methods for quan- tifying anthropogenic noise over large spatial and long tem- poral scales and assessing the effects of this noise on behav- ior of many species of marine animals, especially movement and communication. Back on land, the situation is not much better. Kurt Fristrup of the National Park Service demonstrated how even the places humans designate as wild and protected are not immune from noise. The Park Service was established to sup- port goals such as leaving wild areas unimpaired, ensuring superb environmental quality, making certain natural processes predominate, and preserving authentic landscapes. However, transportation noise is a major problem in nation- al parks. Evaluation of the transportation networks within parks revealed motorcycles have a greater than 600 km 46 Acoustics Today, October 2011