Discipline: Biological Sciences
Subcategory: Ecology
Session: 2
Room: Virginia B
Sabena Siddiqui - University of Hawaii at Hilo
Co-Author(s): Adam A. Pack, University of Hawaii Hilo, HI; Alison K. Stimpert, Moss Landing Laboratories, CA; Patrick J. Hart, University of Hawaii Hilo, HI
Despite the dominance of male song in the humpback whale communication research literature, increasing attention has been paid to non-song calls. However, relatively few studies have examined these calls in the humpback whale breeding grounds, and currently there are no descriptions of call characteristics in conjunction with underwater video in non-calf pods. Thus, little is known about the relationships between non-song calls, pod type, and subsurface behavior during adult interactions such as mate competition or stationary pair associations. This study characterizes call types in relation to pod type and composition, sea state, and behavioral state. The dataset consisted of subsurface video and audio recordings from an archival database collected from humpback whales in different pod types in waters off Maui from 1998-2007. Video and audio data were recorded using a mini-DV camera in an underwater housing outfitted with a single uncalibrated hydrophone (useable system response: 7Hz ≥ 20kHz). Calls were manually identified in spectrograms in Raven Pro, and cluster analysis was used to classify call types. Approximately 75 hours of acoustic recordings containing non-song calls were analyzed. Over the study period, 1,533 pods were recorded and 372 (24%) pods were found to contain non-song calls. Of these 372 pods, competitive pods were found to contain non-song calls more frequently than any other pod type (53%), followed by dyads (19%) and mother-calf escort pods (17%) with all other pod types accounting for only 11%. Non-song sound production may be important for male-male aggressive interactions, or female communication with potential mates. The results of this study will allow for comparisons in behavioral usage between non-song call types in Hawaii and other populations with already established call types in very different behavioral contexts across the wide geographical range of this species.
Funder Acknowledgement(s): This study was supported, in part, by a grant from the NSF CREST program award to the TCBES program at University of Hawaii Hilo, The Dolphin Institute, University of Hawaii at Manoa, and Earthwatch International. I would like to thank all the researchers and volunteers involved with the fieldwork and the collection of this data.
Faculty Advisor: Dr. Adam Pack, pack@hawaii.edu
Role: Other than collecting the data in the field, I prepared the data and analyzed it to get to the results of this study for my thesis work. I analyzed the video using both behavioral and acoustic analysis to understand factors such as call rate, call type, and what behaviors and pod types correlate to these various factors. I used Raven Pro software to analyze acoustic data of each pod used in this study. This was followed by statistical analysis.