01785nas a2200217   4500008004100000245012800041210006900169520098500238653002201223653001201245653001701257653003401274653001801308653001501326653000801341653002201349653001601371100002001387700002401407856013601431       2019                        eng d00aAcoustically estimated size distribution of sperm whales ( <i>Physeter macrocephalus</i>) off the east coast of New Zealand0 aAcoustically estimated size distribution of sperm whales iPhyset3 a<p>The length-frequency distribution of sperm whales (Physeter macrocephalus) was studied on the east coast of NZ using passive acoustic recorders moored offshore of Kaikoura, Cape Palliser and Castlepoint. Sperm whale&rsquo;s echolocation signals are unique among odontocete species. Their clicks are composed by multiple pulses resulting from the sound transmission within the whale head. The total length of the whales can be estimated by measuring the time delay between these pulses. A total of 997 length measurements were obtained from click trains using cepstral analysis (mean&thinsp;=&thinsp;14.6 m; min&thinsp;=&thinsp;9.6 m; max&thinsp;=&thinsp;18.3 m; std&thinsp;=&thinsp;1 m). The size-frequency distributions at all three locations were similar, although animals smaller than 12 m were not present offshore of Kaikoura. Animals of various sizes appeared to be present all year round, with no apparent seasonality in the occurrence of any size class.</p>
10acepstral analysis10aceptrum10aecholocation10alength-frequency distribution10amarine mammal10aodontocete10aPAM10apassive acoustics10asperm whale1 aGiorli, Giacomo1 aGoetz, Kimberly, T.  uhttps://www.tandfonline.com/doi/full/10.1080/00288330.2019.1679843https://www.tandfonline.com/doi/pdf/10.1080/00288330.2019.1679843