Dear MARMAM Colleagues,
On behalf of my co-authors, I am delighted
to announce the publication of our recent paper:
Shabangu FW, Hofmeyr GJG, Probert R, Connan
M, Buhrmann CA, Gridley T. 2022. In-air acoustic repertoire and associated
behaviour of wild juvenile crabeater seals during rehabilitation. Bioacoustics,
https://doi.org/10.1080/09524622.2022.2108145
Abstract
In-air sounds of pinnipeds are important
for interactions with conspecifics and threat displays. However, little is
known about the in-air acoustic repertoire and associated behaviour of
crabeater seals Lobodon carcinophaga. We investigated the in-air
acoustic repertoire and associated behaviour of two male and one female wild juvenile
crabeater seals that beached separately, and were rehabilitated in Durban and
Gqeberha, South Africa. In-air sounds were visually identified and categorised
into five classes validated via random forest model classification: brief,
intermediate, and long moan calls, croaks, and hisses. Hisses were common (n =
25,105 sounds from 136 hrs of acoustic recordings) and detected during heightened
arousal states and interactions with animal care staff and a conspecific.
Furthermore, hisses were also recorded in low arousal states during exhalation.
Moan calls (n = 241) were only detected from two of the three seals. During
rehabilitation, the female seal ceased producing moan calls and later produced a
series of croaks (n = 204). Acoustic characteristics of in-air moan calls
differed from published underwater moan calls according to duration, minimum,
and maximum frequencies, and pulse repetition rate. Our study shows that the
in-air acoustic repertoire and associated behaviour of these Antarctic seals
are dynamic, vary inter-individually and are context dependent.
Best
regards,
Fannie
_ _ _ _ _ _
_ _ _ _ _ _ _ _ _
Fannie W.
Shabangu, PhD
Marine
Biologist
Department
of Forestry, Fisheries and the Environment
Cape Town,
South Africa
Mobile: +27
74 220 0210
Tel: +27 21
402 3553
Research
Fellow
Mammal
Research Institute Whale Unit
University
of Pretoria
Hatfield,
South Africa