Meeting Abstract
Aquatic animals that require sound to communicate and find mates need to filter out relevant signals from noise in their environment. There are limited studies on how ecologically relevant noise affects aquatic life, and even fewer studies examining the effect of noise on fish that use sound to communicate for reproduction. An excellent model to examine the effect of anthropogenic noise on acoustic behavior is the oyster toadfish (Opsanus tau). O. tau use an advertisement called the “boatwhistle”, to find mates yet appear to thrive and reproduce within the waters surrounding New York City, a large and noisy urban environment. The goal of this study was to categorize and quantify noise and O. tau vocalizations and examine any changes in acoustic behavior in response to noise. We hypothesized that over a 24 hr period, the number of O. tau calls would be greatest when anthropogenic noise is lowest (after dark), and toadfish will temporally space their calls to avoid masking by noise throughout the day. We collected passive acoustic recordings from Manhattan’s Pier 25 (Hudson River, NY) near known O. tau breeding sites. We quantified the number of O. tau vocalizations and categorized types of noise, counted the number occurrences, and calculated the duration of anthropogenic noise over 24 periods. We found that anthropogenic noise (i.e., construction noise and boat traffic) is within O. tau’s hearing range and mostly occurs during daylight hours. O. tau call both day and night but 70% of calls happen between sunset and sunrise. Additionally, we observed an inverse relationship between abundance of noise and the number of O. tau calls throughout a 24 hr period, suggesting a behavioral strategy for communication in a noisy environment.
