Details:

Journal Title:
PLOS ONE
Personal Author:
Constaratas, Alexandra N. ; McDonald, Mark A. ; Goetz, Kimberly T. ; Giorli, Giacomo
Constaratas, Alexandra N. ; McDonald, Mark A. ; Goetz, Kimberly T. ; Giorli, Giacomo Less -
NOAA Program & Office:
NMFS (National Marine Fisheries Service) ; AFSC (Alaska Fisheries Science Center)
NMFS (National Marine Fisheries Service) ; AFSC (Alaska Fisheries Science Center) Less -
Description:
Southern fin whales (Balaenoptera physalus) are known to migrate from the Antarctic to mid-latitudes during winter for breeding, but the occurrence and distribution of this species is not well known in the waters around New Zealand. The ‘doublet’ calls are one of the main calls emitted specifically by fin whales and repeated in a regular pattern, which make the acoustic detection of these calls relevant to detect the presence of fin whales. Using a signal processing algorithm to detect ‘doublet’ calls emitted by fin whales, we studied the occurrence, characteristics and seasonality of these ‘doublet’ calls in two regions around New Zealand; Cook Strait in 2016/2017 and offshore Gisborne in 2014/2015. The call detection procedure consisted of binarization of the spectrogram and a cross-correlation between the binarized spectrogram and a template of binarized ‘doublet’ calls spectrogram. A binarization threshold for the data spectrograms and a cross correlation threshold were then determined through multiple trials on a training dataset and a Receiver Operating Characteristics (ROC) curve. Fin whale ‘doublet’ calls occurred on the east side of New Zealand’s Cook Strait during austral winter, specifically in June 2017 and offshore Gisborne in June-August 2014. No ‘doublet’ calls were detected on the west side of Cook Strait. The ‘doublet’ calls’ Inter-Note Interval (INI) was similar in both datasets. However, there was a difference in alternation of the mean frequency for both HF components of ‘doublet’ calls in Cook Strait and Gisborne. As the song types were compared with those previously described in the literature, our findings suggest that some fin whales wintering in New Zealand waters may be part of a broader ‘acoustic population’ whose range extends west to southern Australia and south to Antarctica.
Keywords:
[+]
Whales
Source:
PLOS ONE, 16(7)
DOI:
https://doi.org/10.1371/journal.pone.0253737
Document Type:
Journal Article
Place as Subject:
New Zealand
Rights Information:
CC BY
Compliance:
Submitted
Main Document Checksum:
[+]
urn:sha256:003cb2d12bdfb75b5a5749761e9ead11f289b1f3419b1a21999db88ef78297a6
Download URL:
https://repository.library.noaa.gov/view/noaa/32024/noaa_32024_DS1.pdf
File Type:

Supporting Files

• Costaratas_PlosOne_2021.xml

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