A comparison of Northeast Atlantic killer whale (Orcinus orca) stereotyped call repertoires

Funding for data collection was provided by the BBC Natural History Unit, Fundação para a Ciência e a Tecnologia (grant number SFRH/BD/30303/2006), the Icelandic Research Fund (i. Rannsóknasjóður) through a START Postdoctoral Fellowship (grant number 120248042) and a Project Grant (grant number 163060‐051), the National Geographic Global Exploration Fund (grant number GEFNE65‐12), a Marie Curie International Incoming Fellowship (project number 297116), the Office of Naval Research (grant number N00014‐08‐1‐0984), and a Russell Trust Award from the University of St. Andrews.Killer whale call repertoires can provide information on social connections among groups and populations. Killer whales in Iceland and Norway exhibit similar ecology and behavior, are genetically related, and are presumed to have been in contact before the collapse of the Atlanto-Scandian herring stock in the 1960s. However, photo-identification suggests no recent movements between Iceland and Norway but regular movement between Iceland and Shetland. Acoustic recordings collected between 2005 and 2016 in Iceland, Norway, and Shetland were used to undertake a comprehensive comparison of call repertoires of Northeast Atlantic killer whales. Measurements of time and frequency parameters of calls from Iceland (n = 4,037) and Norway (n = 1,715) largely overlapped in distribution, and a discriminant function analysis had low correct classification rate. No call type matches were confirmed between Iceland and Norway or Shetland and Norway. Three call types matched between Iceland and Shetland. Therefore, this study suggests overall similarities in time and frequency parameters but some divergence in call type repertoires. This argues against presumed past contact between Icelandic and Norwegian killer whales and suggests that they may not have been one completely mixed population.PostprintPeer reviewe

Isotopic evidence of limited exchange between Mediterranean and eastern North Atlantic fin whales

RATIONALE The relationship between stocks of fin whales inhabiting the temperate eastern North Atlantic and the Mediterranean Sea is subject to controversy. The use of chemical markers facilitates an alternative insight into population structure and potential borders between stocks because the two areas present dissimilar isotopic baselines. METHODS Baleen plates, composed of inert tissue that keeps a permanent chronological record of the isotopic value of body circulating fluids, were used to investigate connectivity and boundaries between the stocks. Values were determined by continuous flow isotope ratio mass spectrometry. RESULTS Stable isotopes confirm that, while the two subpopulations generally forage in well-differentiated grounds, some individuals with characteristic Atlantic values do penetrate into the Mediterranean Sea up to the northernmost latitudes of the region. As a consequence, the border between the two putative subpopulations may be not as definite as previous acoustic investigations suggested. The discriminant function obtained in this study may assist researchers to use baleen plate isotopic data to assign the origin of fin whales of uncertain provenance. CONCLUSIONS This study strengthens the stock subdivision currently accepted for management and conservation while recognizes a low level of exchange between the Mediterranean and temperate eastern North Atlantic subdivisions. Copyright © 2013 John Wiley & Sons, Ltd.Peer Reviewe

A review of the Norwegian whaling and whale research in the North-East Atlantic Ocean in post-war years

Whaling Committee

Improvements on colour histogram-based CBIR

NORSK: Denne oppgaven prøver ut en del nye metoder for innholdsbasert bildesøk, med det for øye å forbedre resultatene fra rene fargehistogram-baserte metoder. Oppgaven ser også på hvordan man kan måle resultatene fra disse metodene. I stedet for å kun basere seg på sannhetssett-databaser foreslår denne oppgaven en mer utstrakt bruk av spørreundersøkelser. Selv om bildesøkmetodene som blir foreslått ikke gav noe bedre resultat enn rene fargehistogram, så viste resultatene fra spørreundersøkelsen at folk ikke nødvendigvis mener det samme som resultatene fra sannhetssett-databaser