Patterns and dynamics of rest-phase hypothermia in wild and captive blue tits during winter.
(2009) In Journal of Comparative Physiology B 179. p.737-745- Abstract
- We evaluated biotic and abiotic predictors of rest-phase hypothermia in wintering blue tits (Cyanistes caeruleus) and also assessed how food availability influences nightly thermoregulation. On any given night, captive blue tits (with unrestricted access to food) remained largely homeothermic, whereas free-ranging birds decreased their body temperature (T (b)) by about 5 degrees C. This was not an effect of increased stress in the aviary as we found no difference in circulating corticosterone between groups. Nocturnal T (b) in free-ranging birds varied with ambient temperature, date and time. Conversely, T (b) in captive birds could not be explained by climatic or temporal factors, but differed slightly between the sexes. We argue that the... (More)
- We evaluated biotic and abiotic predictors of rest-phase hypothermia in wintering blue tits (Cyanistes caeruleus) and also assessed how food availability influences nightly thermoregulation. On any given night, captive blue tits (with unrestricted access to food) remained largely homeothermic, whereas free-ranging birds decreased their body temperature (T (b)) by about 5 degrees C. This was not an effect of increased stress in the aviary as we found no difference in circulating corticosterone between groups. Nocturnal T (b) in free-ranging birds varied with ambient temperature, date and time. Conversely, T (b) in captive birds could not be explained by climatic or temporal factors, but differed slightly between the sexes. We argue that the degree of hypothermia is controlled predominantly by birds' ability to obtain sufficient energy reserves during the day. However, environmental factors became increasingly important for thermoregulation when resources were limited. Moreover, as birds did not enter hypothermia in captivity when food was abundant, we suggest that this strategy has associated costs and hence is avoided whenever resource levels permit. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1392311
- author
- Nord, Andreas LU ; Nilsson, Johan LU ; Sandell, Maria LU and Nilsson, Jan-Åke LU
- organization
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Comparative Physiology B
- volume
- 179
- pages
- 737 - 745
- publisher
- Springer
- external identifiers
-
- wos:000268312100008
- scopus:70349773844
- pmid:19352685
- ISSN
- 0174-1578
- DOI
- 10.1007/s00360-009-0357-1
- language
- English
- LU publication?
- yes
- id
- 06db743c-a67f-491b-8812-4b8760f5458e (old id 1392311)
- date added to LUP
- 2016-04-01 12:24:30
- date last changed
- 2024-04-09 12:11:54
@article{06db743c-a67f-491b-8812-4b8760f5458e,
abstract = {{We evaluated biotic and abiotic predictors of rest-phase hypothermia in wintering blue tits (Cyanistes caeruleus) and also assessed how food availability influences nightly thermoregulation. On any given night, captive blue tits (with unrestricted access to food) remained largely homeothermic, whereas free-ranging birds decreased their body temperature (T (b)) by about 5 degrees C. This was not an effect of increased stress in the aviary as we found no difference in circulating corticosterone between groups. Nocturnal T (b) in free-ranging birds varied with ambient temperature, date and time. Conversely, T (b) in captive birds could not be explained by climatic or temporal factors, but differed slightly between the sexes. We argue that the degree of hypothermia is controlled predominantly by birds' ability to obtain sufficient energy reserves during the day. However, environmental factors became increasingly important for thermoregulation when resources were limited. Moreover, as birds did not enter hypothermia in captivity when food was abundant, we suggest that this strategy has associated costs and hence is avoided whenever resource levels permit.}},
author = {{Nord, Andreas and Nilsson, Johan and Sandell, Maria and Nilsson, Jan-Åke}},
issn = {{0174-1578}},
language = {{eng}},
pages = {{737--745}},
publisher = {{Springer}},
series = {{Journal of Comparative Physiology B}},
title = {{Patterns and dynamics of rest-phase hypothermia in wild and captive blue tits during winter.}},
url = {{http://dx.doi.org/10.1007/s00360-009-0357-1}},
doi = {{10.1007/s00360-009-0357-1}},
volume = {{179}},
year = {{2009}},
}