Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?

The current study provides details of sleep (or inactivity) in two wild, free-roaming African elephant matriarchs studied in their natural habitat with remote monitoring using an actiwatch subcutaneously implanted in the trunk, a standard elephant collar equipped with a GPS system and gyroscope, and...

Full description

Bibliographic Details
Main Authors: Nadine Gravett, Adhil Bhagwandin, Robert Sutcliffe, Kelly Landen, Michael J Chase, Oleg I Lyamin, Jerome M Siegel, Paul R Manger
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC5382951?pdf=render
_version_ 1811235562116349952
author Nadine Gravett
Adhil Bhagwandin
Robert Sutcliffe
Kelly Landen
Michael J Chase
Oleg I Lyamin
Jerome M Siegel
Paul R Manger
author_facet Nadine Gravett
Adhil Bhagwandin
Robert Sutcliffe
Kelly Landen
Michael J Chase
Oleg I Lyamin
Jerome M Siegel
Paul R Manger
author_sort Nadine Gravett
collection DOAJ
description The current study provides details of sleep (or inactivity) in two wild, free-roaming African elephant matriarchs studied in their natural habitat with remote monitoring using an actiwatch subcutaneously implanted in the trunk, a standard elephant collar equipped with a GPS system and gyroscope, and a portable weather station. We found that these two elephants were polyphasic sleepers, had an average daily total sleep time of 2 h, mostly between 02:00 and 06:00, and displayed the shortest daily sleep time of any mammal recorded to date. Moreover, these two elephants exhibited both standing and recumbent sleep, but only exhibited recumbent sleep every third or fourth day, potentially limiting their ability to enter REM sleep on a daily basis. In addition, we observed on five occasions that the elephants went without sleep for up to 46 h and traversed around 30 km in 10 h, possibly due to disturbances such as potential predation or poaching events, or a bull elephant in musth. They exhibited no form of sleep rebound following a night without sleep. Environmental conditions, especially ambient air temperature and relative humidity, analysed as wet-bulb globe temperature, reliably predict sleep onset and offset times. The elephants selected novel sleep sites each night and the amount of activity between sleep periods did not affect the amount of sleep. A number of similarities and differences to studies of elephant sleep in captivity are noted, and specific factors shaping sleep architecture in elephants, on various temporal scales, are discussed.
first_indexed 2024-04-12T11:54:13Z
format Article
id doaj.art-d49d342f7de24630993a480f71d8b750
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-12T11:54:13Z
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-d49d342f7de24630993a480f71d8b7502022-12-22T03:34:05ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01123e017190310.1371/journal.pone.0171903Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?Nadine GravettAdhil BhagwandinRobert SutcliffeKelly LandenMichael J ChaseOleg I LyaminJerome M SiegelPaul R MangerThe current study provides details of sleep (or inactivity) in two wild, free-roaming African elephant matriarchs studied in their natural habitat with remote monitoring using an actiwatch subcutaneously implanted in the trunk, a standard elephant collar equipped with a GPS system and gyroscope, and a portable weather station. We found that these two elephants were polyphasic sleepers, had an average daily total sleep time of 2 h, mostly between 02:00 and 06:00, and displayed the shortest daily sleep time of any mammal recorded to date. Moreover, these two elephants exhibited both standing and recumbent sleep, but only exhibited recumbent sleep every third or fourth day, potentially limiting their ability to enter REM sleep on a daily basis. In addition, we observed on five occasions that the elephants went without sleep for up to 46 h and traversed around 30 km in 10 h, possibly due to disturbances such as potential predation or poaching events, or a bull elephant in musth. They exhibited no form of sleep rebound following a night without sleep. Environmental conditions, especially ambient air temperature and relative humidity, analysed as wet-bulb globe temperature, reliably predict sleep onset and offset times. The elephants selected novel sleep sites each night and the amount of activity between sleep periods did not affect the amount of sleep. A number of similarities and differences to studies of elephant sleep in captivity are noted, and specific factors shaping sleep architecture in elephants, on various temporal scales, are discussed.http://europepmc.org/articles/PMC5382951?pdf=render
spellingShingle Nadine Gravett
Adhil Bhagwandin
Robert Sutcliffe
Kelly Landen
Michael J Chase
Oleg I Lyamin
Jerome M Siegel
Paul R Manger
Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?
PLoS ONE
title Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?
title_full Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?
title_fullStr Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?
title_full_unstemmed Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?
title_short Inactivity/sleep in two wild free-roaming African elephant matriarchs - Does large body size make elephants the shortest mammalian sleepers?
title_sort inactivity sleep in two wild free roaming african elephant matriarchs does large body size make elephants the shortest mammalian sleepers
url http://europepmc.org/articles/PMC5382951?pdf=render
work_keys_str_mv AT nadinegravett inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT adhilbhagwandin inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT robertsutcliffe inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT kellylanden inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT michaeljchase inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT olegilyamin inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT jeromemsiegel inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers
AT paulrmanger inactivitysleepintwowildfreeroamingafricanelephantmatriarchsdoeslargebodysizemakeelephantstheshortestmammaliansleepers