Supernumerary teeth observed in a live True's beaked whale in the Bay of Biscay

James R Robbins; Travis Park; Ellen J Coombs

doi:10.7717/peerj.7809

Supernumerary teeth observed in a live True's beaked whale in the Bay of Biscay

PeerJ. 2019 Oct 14:7:e7809. doi: 10.7717/peerj.7809. eCollection 2019.

Authors

James R Robbins^{1

2}, Travis Park³, Ellen J Coombs^{3

4}

Affiliations

¹ ORCA, Portsmouth, United Kingdom.
² School of Biological and Marine Sciences, University of Plymouth, Plymouth, United Kingdom.
³ Department of Life sciences, Natural History Museum, London, United Kingdom.
⁴ Department of Genetics, Evolution, and Environment, University College London, University of London, London, United Kingdom.

Abstract

Mesoplodont beaked whales are one of the most enigmatic mammalian genera. We document a pod of four beaked whales in the Bay of Biscay breaching and tail slapping alongside a large passenger ferry. Photographs of the animals were independently reviewed by experts, and identified as True's beaked whales (Mesoplodon mirus). This is the first conclusive live sighting of these animals in the north-east Atlantic, and adds information to previous sightings that are likely to have been M. mirus. Photographs of an adult male appears to show two supernumerary teeth posterior to the apical mandibular tusks. Whilst analysed museum specimens (n = 8) did not show evidence of alveoli in this location, there is evidence of vestigial teeth and variable dentition in many beaked whale species. This is the first such record of supernumerary teeth in True's beaked whales.

Keywords: Bay of Biscay; Cetacea; Dentition; Mesoplodon mirus; Morpohology; True’s beaked whale.

Grants and funding

James Robbins was supported by ORCA, who are funded by memberships and supporters. This research was supported by a Marie Skłodowska-Curie Individual Fellowship (748167/ECHO) to Travis Park. The London Natural Environment Research Council Doctoral Training Partnership (London NERC DTP) training grant NE/L002485/1 supported Ellen Coombs. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.