Marine Mammal

Science & Conservation

We are publishing our results and what we see and hear as scientific publications, in the media, and or write reports to organizations and the governments.

Peer reviewed articles

1) “Evidence for discrimination between feeding sounds of familiar fish and unfamiliar mammal‑eating killer whale ecotypes by long‑finned pilot whales”


Killer whales (KW) may be predators or competitors of other cetaceans. Since their foraging behavior and acoustics differ among populations (‘ecotypes’), we hypothesized that other cetaceans can eavesdrop on KW sounds and adjust their behavior according to the KW ecotype. We performed playback experiments on long-finned pilot whales (Globicephala melas) in Norway using familiar fish-eating KW sounds (fKW) simulating a sympatric population that might compete for foraging

areas, unfamiliar mammal-eating KW sounds (mKW) simulating a potential predator threat, and two control sounds. We assessed behavioral responses using animal-borne multi-sensor tags and surface visual observations. Pilot whales barely changed behavior to a broadband noise (CTRL−), whereas they were attracted and exhibited spyhops to fKW, mKW, and to a repeated-tonal upsweep signal (CTRL+). Whales never stopped nor started feeding in response to fKW, whereas they reduced or stopped foraging to mKW and CTRL+. Moreover, pilot whales joined other subgroups in response to fKW and CTRL+, whereas they tightened individual spacing within group and reduced time at surface in response to mKW. Typical

active intimidation behavior displayed to fKW might be an antipredator strategy to a known low-risk ecotype or alternatively a way of securing the habitat exploited by a heterospecific sympatric population. Cessation of feeding and more cohesive approach to mKW playbacks might reflect an antipredator behavior towards an unknown KW ecotype of potentially higher risk. We conclude that pilot whales are able to acoustically discriminate between familiar and unfamiliar KW ecotypes, enabling them to adjust their behavior according to the perceived disturbance type.

Charlotte Curé· Saana Isojunno· Heike I. Vester· Fleur Visser· Machiel Oudejans· Nicoletta Biassoni· Mathilde Massenet· Lucie Barluet de Beauchesne· Paul J. Wensveen· Lise D. Sivle· Peter L. Tyack·Patrick J. O. Miller

2) Vocal repertoire of long-finned pilot whales (Globicephala melas) in northern Norway

The knowledge of the vocal repertoire of pilot whales is very limited. In this paper, the vocal repertoire of long-finned pilot whales recorded during different encounters in the Vestfjord in northern Norway between November 2006 and August 2010 are described. Sounds were analysed using two different methods: (1) an observer-based audio-visual inspection of FFT-derived spectrograms, with which, besides a general variety of clicks, buzzes, nonharmonic sounds, and whistles, 129 different distinct call types and 25 subtypes were distinguished. These call types included pulsed calls and discrete structured whistles varying from simple to highly complex structures composed of several segments and elements. In addition, ultrasonic whistles previously not described for pilot whales were found. In addition to the diversity of single calls, call sequences consisting of repetitions and combinations of specific call types were recorded and (2) a parametric approach that permitted the confirmation of the high variability in pilot whale call structures was developed. It is concluded that the pilot whale vocal repertoire is among the most complex for the mammalian species and the high structural variability, along with call repetitions and combinations, require a closer investigation to judge their importance for vocal communication.

Copyright (2017) Acoustical Society of America. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the Acoustical Society of America. The following article appeared in (citation of published article) and may be found at

3) “Quantifying group specificity of animal vocalizations without specific sender information”

Heike Vester, Kurt Hammerschmidt, Marc Timme, and Sarah Hallerberg. PHYSICAL REVIEW E 93, 022138, 2016 Vester et al PhysRevE

Recordings of animal vocalization can lack information about sender and context. This is often the case in studies on marine mammals or in the increasing number of automated bioacoustics monitorings. Here, we develop a framework to estimate group specificity without specific sender information. We introduce and apply a bag-of-calls-and-coefficients approach (BOCCA) to study ensembles of cepstral coefficients calculated from vocalization signals recorded from a given animal group. Comparing distributions of such ensembles of coefficients by computing relative entropies reveals group specific differences. Applying the BOCCA to ensembles of calls recorded from group of long-finned pilot whales in northern Norway, we find that differences of vocalizations within social groups of pilot whales (Globicephala melas) are significantly lower than intergroup differences.

Media coverage:
Nature Physics

4) Research note: “Whale watching in Norway caught between more traditional hunting canons and the lucrative promise of seismic airguns” 2015.

Giovanna Bertella and Heike Iris Vester, Tourism in Marine Environments.

5) “First record of killer whales (Orcinus orca) feeding on Atlantic salmon (Salmo salar) in northern Norway suggest a multi-prey feeding type”

Heike Vester and Kurt Hammerschmidt


Occurrence of killer whales in Norway is linked to the migration of the herring population with most sightings during wintertime. Here we describe the first record of North Atlantic killer whales feeding on Atlantic salmon inside a fjord in northern Norway during summertime, thus adding an important factor in understanding the feeding ecology of North Atlantic killer whales.

Marine Biodiversity Records, page 1 of 5. # Marine Biological Association of the United Kingdom, 2013 doi:10.1017/S1755267212001030; Vol. 6; e9; 2013 Published online

6) “Dietary variation within and between populations of northeast Atlantic killer whales Orcinus orca inferred from δ13C and δ15N analyses”.

Foote AD, Vester H, Vikingsson GA, Newton J (2012)  Marine Mammal Science Foote_et_al_2012_MarMammSci

7) “Call for cooperation to contain damage by Chile’s salmon farms”

Heike Vester & Marc Timme, 2010. Nature, Vol.465 pp. 869 / 17 June 2010. PDF AysenThreatenNature20101

8) “Southernmost distribution of common Bottlenose dolphins (Tursiops truncatus) in the eastern South Pacific”,

Carlos Olavarría, Jorge Acevedo, Heike I. Vester, José Zamorano-Abramson, Francisco A. Viddi, Jorge Gibbons, Emma Newcombe, Juan Capella, A. Rus Hoelzel, Marcelo Flores, Rodrigo Hucke-Gaete & Juan Pablo Torres-Flórez, 2010. Aquatic Mammals, Vol 36 (3), pp 288-293. PDF 36_3_Olavarría1

9) Genetic differentiation within a North Atlantic killer whale ecotype”

Molecular Ecology. Andrew D. Foote, Julia Vilstrup, Renaud de Stephanis, Philippe Verborgh, Sandra C. Abel Nielsen, Morten Rasmussen, Robert J. Reid, Kelly M. Robertson, Lars Kleivane, Nils Øien, Tiu Similä, Heike Vester, Gísli A. Vikingsson,Robert Deaville, Emer Rogan, Eske Willerslev, M. Thomas P. Gilbertand Stuart B. Piertney, 2010.  PDF Foote-et-al-2010-Mol-Ecol

10) Click sounds produced by cod (Gadus morhua)

Vester, H.I., Folkow, L.P. and A.S. Blix, February 2004. J.Acoust.Soc.Am. Vol. 115, No. 2, pp. 914-919. PDF codclicks-hvester-etal-20041


PhD thesis:

“Vocal repertoire of two matrilineal social whale species:
Long-finned Pilot whales (Globicephala melas) and Killer whales (Orcinus orca) in northern Norway”, Heike Vester
2017 University of Goettingen, Germany

“Revealing structure in vocalisations of parrots and social whales”
Noriega Romero Vargas, Maria Florencia
2018 University of Goettingen, Germany

Master & Bachelor thesis:

Master of Science Thesis “Applied Computer Science” 15.10.2015
Towards Automated Photo Identification of Killer Whales
by Burooj Ghani,
Department of Computational Neuroscience, Third Institute of Physics – Biophysics,
Georg-August-Universität Göttingen, Max Planck Institute for Dynamics and Self-Organization, Göttingen.

“Distribution of cetaceans in Vestfjorden, Norway, and possible impacts of seismic surveys”
Master thesis by Felipe Matos, Faculty of Biosciences and Aquaculture, University of Nordland
May 2015

 “Distribution and vocal behavior of Atlantic white-sided dolphins (Lagenorhynchus acutus) in northern Norway”.
Master thesis by Ellyne Hamran, Faculty of Biosciences and Aquaculture, University of Nordland 2014.

Photo-Identification of Salmon Eating Killer Whales (Orcinus orca) in Norway (2012).Kristin Reehaug Jacobsen from the University of Nordland in Bodø has completed her bachelor thesis 15.6.2012

Investigating Specific Groups of Killer Whales (Orcinus orca) Through Photo Identification in Norway (2012). Ellyne Dudkowski from the University of Nordland in Bodø has completed her bachelor thesis 15.6.2012 Dudkowski_Bachelors_Thesis_on_Killer_Whales_3

2008 Master project by Silke Nielebock from the University of Oldenburg in Germany. Her thesis was completed 2008 and can be downloaded in German: okotourismus-in-norwegen-touristenprofil-des-okotourismusbetriebs-ocean-sounds-auf-den-lofoten
2008 article by Silke Nielebock AK Norden “Okoturismus in Norwegen”

2008 Philosophy student Martin Lee Miller spent some time with us in 2007 to study the north, the whales and the visitors. He completed his thesis: Symphony of Silence at the University of Oslo.

Posters & conferences & technical reports:

The Vocal Behavior and Distribution of the Atlantic White-sided Dolphins (Lagenorhynchus acutus) in Northern Norway,” poster presentation at the European Cetacean Society, 23rd – 25th March 2015 in St. Julian’s, Malta.

Ellyne Hamran (1), Heike Vester (1, 2), Jarle Tryti Nordeide (1)

(1)  University of Nordland, Faculty of Biosciences and Aquaculture, 8049 Bodø, Norway; (2)  Ocean Sounds, 8312 Henningsvær, Norway

The Atlantic white-sided dolphins (Lagenorhynchus acutus) are migratory dolphins and their vocal behavior and distribution are understudied in Norway. Vessel based surveys were conducted in order to determine the vocal behavior and occurrence in the Vestfjorden in northern Norway. Hydrophone recordings were used to describe the vocal behavior of clicks, whistles, calls, buzzes and to determine the presence or absence of stereotyped whistles. Clicks (98-99%) were the most abundant sound produced and whistles (65.4%-76.0% excluding clicks) were equally abundant second to clicks. Stereotyped whistles were also observed (e.g. 11-20 kHz, length 853 msec). The relationship of vocal behavior and activity resulted in a dependence on activity: foraging, socializing, milling, and traveling. Sound production increased during socializing and calls were observed most commonly during traveling (32.4%) and least common during foraging (18.8%). Buzzes varied (0-14.0%) and were absent during milling. Photo-ID and sightings were used for tracking and a total of 72 yearly sightings were observed including 55 photo-ID individuals of which 29 individuals were re-sighted again. Two of the 15 re-sighted individuals were observed on 6 occasions with gaps no greater than two years. Many sightings of Atlantic white-sided dolphins including the re-sightings of photo-ID individuals indicate a stronger presence of Atlantic white-sided dolphins than previously reported in the Vestfjorden in northern Norway. 

North Atlantic Killer Whale workshop 2012 in Galway, Ireland: NKW-abstract-book


Vester, H.I., L.P. Folkow and A. Schytte Blix, 2001. “Underwater vocalisation of captive hooded and harp seals during live fish hunting.”Proc. Soc.Mar.Mamm.Conf. in Vancouver, November 2001.

Vester, H.I., L.P. Folkow and A. Schytte Blix, 2001. “Click sounds produced by cod (Gadus morhua) – a possible anti-predator behaviour?” Proc. ICA conference in Rome, September 2001.

Vester, H., 2007.  “Whale watching and ecotourism – a field study from Northern Norway”Proc. of the Global Ecotourism Conference 2007 in Oslo.

Other publications

“Whales and Seascapes of Lofoten”, mulit media DVD, H.Vester & G. Reichtert, 2010.

“Marine Mammals and Fish of Vesteraalen and Lofoten”, H. Vester, Audio CD in cooperation with, 2009.

Whale Watching Guidelines


Whale Guidelines english-02

Guidelines by H. Vester & R. Eriksson, Ocean Sounds & WWF Norway, 2007:
With our 5 years research experience and the help of the WWF Norway, we created a leaflet with new whale watching guidelines. Whale watching in Norway is totally unregulated and there is a need of regulating the boat traffic and human activities around the whales. Whales and whale watching boats are often disturbed by the presence of many boats or boats that drive irresponsible. Please use our guidelines, distribute them and if you go on whale watching tours in Norway, show them to your skipper and guide and ask them to follow it.


Heike Vester, Invited speaker at the Whale Watching workshop, University in Tromsø, Norway. 25th of December 2014.

“Complex communication of social whales” Vester, Heike, Marc Timme and Sarah Hallerberg 27-29 of June 2012, Berlin. Max Planck –Chile research Seminar.        

“Marine Wildlife of Lofoten”, invited speaker at the “Today´s diagnose and preservation of the Cantabric Sea and The North of Europe” Pakea Bizkaia Conference 22nd January 2011, Maritime Museum in Bilbao, Spain.

“Whale and Dolphin communication in Vestfjorden, northern Norway”, speaker at the Aquadyne Technology Awareness Seminar 29th – 30th September 2010 in Oslo

Who says what in the Vestfjord – whale communication”, public lecture at the University of Nordland, northern Norway, 07.10.2009.

Ocean Sounds and Scientific Tourism”, public lecture organised by the Center for Research in Patagonian Ecosystems (CIEP) in Coyhaique, Patagonia, Chile, 24.03.2009.

“Benefits and risks of whale watching – a case study of northern Norway” Workshop on scientific tourism organised by Center for Research in Patagonian Ecosystems (CIEP)in Coyhaique, Patagonia, Chile, 22 -29 of April 2008. (

Whale watching and ecotourism – a field study from Northern Norway”. Speaker at the Global Ecotourism Conference in Oslo, 15th of May 2007.

Participating at the UNEP/GRID workshop: “Linking tourism and conservation” in Arendal in Norway 12-13 May 2007.

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