Funding for this research was provided by:
Associação para a promoção e desenvolvimento do turismo subaquático
Fundação para a Ciência e a Tecnologia (UID/MAR/04292/2013)
Received: 6 March 2018
Revised: 12 May 2018
Accepted: 29 May 2018
First Online: 3 June 2018
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with animals performed by any of the authors. Only non-invasive methods were applied to acquire the biological data.
: All necessary permits for sampling and observational field studies have been obtained by the authors from the competent authorities and are mentioned in the acknowledgements, if applicable.