01287nas a2200169   4500008004100000245007900041210006900120520072400189100002000913700002400933700002000957700001800977700002400995700002601019700002101045856005101066       2018                        eng d00aUnknown beaked whale echolocation signals recorded off eastern New Zealand0 aUnknown beaked whale echolocation signals recorded off eastern N3 a<p>The echolocation signals of most beaked whale species are still unknown. In fact, out of the 22 species comprising the family Ziphiidae, only the echolocation pulses for 7 species have been clearly described. This study describes two distinct beaked whale echolocation signals recorded in the Cook Strait region using passive acoustic technology. These signals differ from previously described Ziphiid species clicks. A description of the time-frequency characteristics of the two signals is provided. Understanding the characteristics of these signals is necessary to correctly identify species from their echolocation signals and enables future monitoring of beaked whales using passive acoustics techniques.</p>
1 aGiorli, Giacomo1 aGoetz, Kimberly, T.1 aDelarue, Julien1 aMaxner, Emily1 aKowarski, Katie, A.1 aMartin, Steven, Bruce1 aMcPherson, Craig  uhttp://asa.scitation.org/doi/10.1121/1.503212701785nas 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/10.1080/00288330.2019.167984301461nas a2200109   4500008004100000245009700041210006900138520104600207100002001253700002401273856005401297       2019                        eng d00aForaging activity of sperm whales (Physeter macrocephalus) off the east coast of New Zealand0 aForaging activity of sperm whales Physeter macrocephalus off the3 a<p>The occurrence and distribution of sperm whales in New Zealand waters is mainly known from whaling records or opportunistic sightings by the public and a systematic estimation of the abundance and distribution has never been conducted. In this study, we investigated the foraging activity and occurrence of sperm whales off the Eastern coast of New Zealand using passive acoustic monitoring techniques. Three acoustic recorders were moored to the ocean floor at different locations on the east side of the North and South Island to collect passive acoustic data from June 2016 until August 2017. A total of 53,823 echolocation click trains were recorded and analyzed to understand the spatial and temporal variation of sperm whale foraging activity. No difference in the foraging activity was found between night-time and day-time periods at any of the locations. Click train detections increased toward the south, suggesting increased foraging activity near Kaikoura. At each station, sperm whale foraging activity varied by month.</p>
1 aGiorli, Giacomo1 aGoetz, Kimberly, T.  uhttp://www.nature.com/articles/s41598-019-48417-5