Funding for this research was provided by:
Department for the Economy
Text and Data Mining valid from 2020-03-18
Received: 18 December 2019
Accepted: 2 March 2020
First Online: 18 March 2020
Ethics approval and consent to participate
: This study was approved by the Queens University Belfast ethics committee (QUB-BS-AREC-19-004) and Belfast Zoo.
: Not applicable.
: The authors declare that they have no competing interests.