Dear MARMAM community,
We’d like to let you know about a new publication on Antarctic fur seals
in the /Proceedings of the Royal Society B/: Evidence for an Allee
effect in a declining fur seal population. doi: 10.1098/rspb.2020.2882
<https://royalsocietypublishing.org/doi/10.1098/rspb.2020.2882?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed>
Abstract: Allee effects play an important role in the dynamics of many
populations and can increase the risk of local extinction. However, some
authors have questioned the weight of evidence for Allee effects in wild
populations. We therefore exploited a natural experiment provided by two
adjacent breeding colonies of contrasting density to investigate the
potential for Allee effects in an Antarctic fur seal (Please feel free
to contact me if you don't have access to the article! Arctocephalus
gazella) population that is declining in response to climate
change-induced reductions in food availability. Biometric time-series
data were collected from 25 pups per colony during two consecutive
breeding seasons, the first of which was among the worst on record in
terms of breeding female numbers, pup birth weights and foraging trip
durations. In previous decades when population densities were higher,
pup mortality was consistently negatively density dependent, with rates
of trauma and starvation scaling positively with density. However, we
found the opposite, with higher pup mortality at low density and the
majority of deaths attributable to predation. In parallel, body
condition was depressed at low density, particularly in the poor-quality
season. Our findings shed light on Allee effects in wild populations and
highlight a potential emerging role of predators in the ongoing decline
of a pinniped species.
Please feel free to contact me if you don't have access to the article!
Kind regards,
Rebecca Nagel
--
Dr. Rebecca Nagel
mail: [email protected]
tel.: +49 521 106-2192
room: VHF-203a
Bielefeld University
Department of Animal Behaviour
PO Box 10 01 31
33501 Bielefeld
Germany
_______________________________________________
MARMAM mailing list
[email protected]
https://lists.uvic.ca/mailman/listinfo/marmam
