[MARMAM] New publication: Whistle characterization of long-beaked common dolphins in the Gulf of California
Dear MARMAM community, My co-authors and I are very pleased to announce the publication of our new paper in Peerj journal. Carlón-Beltrán Ó, Viloria-Gómora L, Urbán R. J, Martínez-Aguilar S, Antichi S. 2023. Whistle characterization of long-beaked common dolphin (*Delphinus delphis* *bairdii*) in La Paz Bay, Gulf of California. PeerJ 11:e15687. http://doi.org/10.7717/peerj.15687 Abstract Long-beaked common dolphin (*Delphinus delphis bairdii*) distribution is limited to the Eastern North Pacific Ocean. Its whistle repertoire is poorly investigated, with no studies in the Gulf of California. The aim of the present study is to characterize the whistles of this species and compare their parameters with different populations. Acoustic monitoring was conducted in La Paz Bay, Gulf of California. Recordings were inspected in spectrogram view in Raven Pro, selecting good quality whistles (n = 270). In the software Luscinia, contours were manually traced to obtain whistle frequencies and duration. Number of steps, inflection points and contour type were visually determined. We calculated the descriptive statistics of the selected whistle parameters and we compared the results with a dolphins population from the Eastern Pacific Ocean. Permutational multivariate analysis of variance (PERMANOVA) was performed to test the intraspecific variation of the whistle parameters among groups. In the present study the mean values (± SD) of the whistle parameters were: maximum frequency = 14.13 ± 3.71 kHz, minimum frequency = 8.44 ± 2.58 kHz and duration = 0.44 ± 0.31 s. Whistles with the upsweep contour were the most common ones (34.44%). The coefficient of variation (CV) values for modulation parameters were high (>100%), in accordance with other studies on dolphins. Whistle parameters showed significant differences among groups. Finally, ending and maximum frequencies, duration and inflection points of the whistles recorded in the present study were lower compared with the parameters of the long-beaked common dolphins from the Eastern Pacific Ocean. This study provides the first whistle characterization of long-beaked common dolphin from the Gulf of California and it will help future passive acoustic monitoring applications in the study area. The paper is open access and can be downloaded at: https://peerj.com/articles/15687/ If you have any questions regarding our work please contact the email: santichi...@alu.uabcs.mx , lvilo...@uabcs.mx Kind regards, Simone Antichi -- PhD candidate Departamento de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur, La Paz, Baja California Sur, Mexico. email: santichi...@alu.uabcs.mx cell: +52 612 228 5196 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] New publication: Differences in the whistles of two ecotypes of bottlenose dolphins from the Gulf of California
Dear MARMAM community, On behalf of my coauthors, I am pleased to share our recent article published in JASA Express Letters. Simone Antichi, Maia Austin, Laura J. May-Collado, Jorge Urbán R, Sergio Martínez-Aguilar, Lorena Viloria-Gómora; Differences in the whistles of two ecotypes of bottlenose dolphins from the Gulf of California. JASA Express Lett 1 May 2023; 3 (5): 051201. Abstract Intraspecific whistle variation in dolphins has been explained in the context of geographical isolation, soundscape, and social structure. Whistles of two ecotypes of bottlenose dolphins from La Paz Bay, Gulf of California, were analyzed. Both ecotypes showed similar whistle contours. However, they could be identified by contour maximum frequency which was predominantly above 15 kHz for oceanic dolphins and below 15 kHz for coastal dolphins. The different whistle frequencies of the two ecotypes could result from differences in group size and acoustic characteristics of their respective habitats, suggesting potential future passive acoustic monitoring applications. The paper and can be downloaded at: https://doi.org/10.1121/10.0019502 If you have any questions regarding our work please contact me at: santichi...@alu.uabcs.mx Best regards, Simone Antichi -- PhD candidate Departamento de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur, La Paz, Baja California Sur, Mexico. email: santichi...@alu.uabcs.mx cell: +52 612 228 5196 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] New publication: Changes in whistle parameters of two common bottlenose dolphin ecotypes as a result of the physical presence of the research vessel
Dear MARMAM community, My co-authors and I are very pleased to announce the publication of our new paper in Peerj journal. Antichi, S., Urbán, J., Martínez-Aguilar, S., & Viloria-Gómora, L. (2022). Changes in whistle parameters of two common bottlenose dolphin ecotypes as a result of the physical presence of the research vessel. PeerJ, 10, e14074. https://doi.org/10.7717/peerj.14074 Abstract In the presence of vessels, dolphins have been found to change their habitat, behavior, group composition and whistle repertoire. The modification of the whistle parameters is generally considered to be a response to the engine noise. Little is known about the impact of the physical presence of vessels on dolphin acoustics. Whistle parameters of the coastal and oceanic ecotypes of common bottlenose dolphins in La Paz Bay, Mexico, were measured after the approach of the research vessel and its engine shutdown. Recordings of 10 min were made immediately after turning off the engine. For analysis, these recordings were divided from minute 0 to minute 5, and from minute 5:01 to minute 10. The whistles of the oceanic ecotype showed higher maximum, minimum and peak frequency in the second time interval compared to the first one. The whistle rate decreased in the second time interval. The whistles of the coastal ecotype showed no difference between the two time intervals. The physical presence of the research vessel could have induced a change in the whistle parameters of the oceanic dolphins until habituation to the vessel disturbance. The oceanic ecotype could increase the whistle rate and decrease the whistle frequencies to maintain acoustic contact more frequently and for longer distances. The coastal ecotype, showing no significant changes in the whistle parameters, could be more habituated to the presence of vessels and display a higher tolerance. The paper is open access and can be downloaded at: https://peerj.com/articles/14074/ If you have any questions regarding our work please contact this email: santichi...@alu.uabcs.mx , lvilo...@uabcs.mx Kind regards, Simone Antichi -- PhD candidate Departamento de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur, La Paz, Baja California Sur, Mexico. email: santichi...@alu.uabcs.mx cell: +52 612 228 5196 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] New publication: vessel impact on the whistle parameters of two ecotypes of bottlenose dolphin in La Paz Bay, Mexico
Dear MARMAM community, On behalf of my coauthors, I am pleased to share our recently published article in the journal Diversity, special issue "Monitoring, Threat Assessment, and Conservation Actions of Cetaceans". Antichi S, Jaramillo-Legorreta AM, Urbán R. J, Martínez-Aguilar S, and Viloria-Gómora L. 2022. Small Vessel Impact on the Whistle Parameters of Two Ecotypes of Common Bottlenose Dolphin (*Tursiops truncatus*) in La Paz Bay, Mexico. Diversity 14:712. https://doi.org/10.3390/d14090712 Abstract Vessel traffic is one of the major sources of underwater anthropogenic noise. Dolphins can modify their vocal repertoire, especially whistles, in presence of vessels to facilitate their communication. Acoustic data were collected (sampling rate 96 kHz) in La Paz Bay, Gulf of California, Mexico. Whistle rate and parameters of the coastal and oceanic ecotypes of common bottlenose dolphins (*Tursiops truncatus*) were measured in absence of vessels and in presence of moving small vessels (size 5–10 m). The peak noise difference was calculated between the two frequency bands dominated by the whistles (2000–20,000 Hz) and the small vessel (500–2000 Hz). In presence of vessels the oceanic ecotype decreased whistle frequencies while the coastal ecotype increased them. Both ecotypes raised whistle frequencies with the decreasing of the peak noise difference. The differences in habitat and group structure could have driven the two ecotypes to react in a different way to the vessel presence. The paper is open access and can be downloaded at: https://www.mdpi.com/1424-2818/14/9/712/htm If you have any questions regarding our work please contact this email: santichi...@alu.uabcs.mx Kind regards, Simone Antichi -- PhD candidate Departamento de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur, La Paz, Baja California Sur, Mexico. email: santichi...@alu.uabcs.mx cell: +52 612 228 5196 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
