Chemical characterisation of potential pheromones from the shoulder gland of the Northern yellow-shouldered-bat, Sturnira parvidens (Phyllostomidae: Stenodermatinae)

Chris G Faulkes; J Stephen Elmore; David A Baines; Brock Fenton; Nancy B Simmons; Elizabeth L Clare

doi:10.7717/peerj.7734

Chemical characterisation of potential pheromones from the shoulder gland of the Northern yellow-shouldered-bat, Sturnira parvidens (Phyllostomidae: Stenodermatinae)

PeerJ. 2019 Sep 18:7:e7734. doi: 10.7717/peerj.7734. eCollection 2019.

Authors

Chris G Faulkes¹, J Stephen Elmore², David A Baines³, Brock Fenton⁴, Nancy B Simmons⁵, Elizabeth L Clare¹

Affiliations

¹ School of Biological & Chemical Sciences, Queen Mary University of London, London, UK.
² Department of Food and Nutritional Sciences, University of Reading, Reading, UK.
³ Baines Food Consultancy Ltd, Thornbury, Bristol, UK.
⁴ Department of Biology, University of Western Ontario, London, ON, Canada.
⁵ Department of Mammalogy Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, USA.

Abstract

Bats of the genus Sturnira (Family Phyllostomidae) are characterised by shoulder glands that are more developed in reproductively mature adult males. The glands produce a waxy secretion that accumulates on the fur around the gland, dyeing the fur a dark colour and giving off a pungent odour. These shoulder glands are thought to play a role in their reproductive behaviour. Using gas chromatography-mass spectrometry, we analysed solvent extracts of fur surrounding the shoulder gland in the northern-shouldered bat, Sturnira parvidens to (i) characterise the chemical composition of shoulder gland secretions for the first time, and (ii) look for differences in chemical composition among and between adult males, sub-adult/juvenile males and adult females. Fur solvent extracts were analysed as liquids and also further extracted using headspace solid-phase microextraction to identify volatile components in the odour itself. Odour fingerprint analysis using non-metric multidimensional scaling plots and multivariate analysis revealed clear and significant differences (P < 0.001) between adult males vs both juvenile males and adult females. The chemical components of the shoulder gland secretion included terpenes and phenolics, together with alcohols and esters, most likely derived from the frugivorous diet of the bat. Many of the compounds identified were found exclusively or in elevated quantities among adult (reproductive) males compared with adult females and non-reproductive (juvenile) males. This strongly suggests a specific role in male-female attraction although a function in male-male competition and/or species recognition is also possible.

Keywords: Chiroptera; Pheromone; Phyllostomidae; Shoulder gland; Sturnira.

Grants and funding

Funding for fieldwork was provided by the Taxonomic Mammalogy Fund of the American Museum of Natural History. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.