Home > Research > Publications & Outputs > Factors influencing overnight loss of body mass...
View graph of relations

Factors influencing overnight loss of body mass in the communal roosts of a social bird

Research output: Contribution to Journal/MagazineJournal articlepeer-review

Published

Standard

Factors influencing overnight loss of body mass in the communal roosts of a social bird. / Hatchwell, Ben J.; Sharp, Stuart P.; Simeoni, Michelle et al.
In: Functional Ecology, Vol. 23, No. 2, 04.2009, p. 367-372.

Research output: Contribution to Journal/MagazineJournal articlepeer-review

Harvard

Hatchwell, BJ, Sharp, SP, Simeoni, M & McGowan, A 2009, 'Factors influencing overnight loss of body mass in the communal roosts of a social bird', Functional Ecology, vol. 23, no. 2, pp. 367-372. https://doi.org/10.1111/j.1365-2435.2008.01511.x

APA

Vancouver

Hatchwell BJ, Sharp SP, Simeoni M, McGowan A. Factors influencing overnight loss of body mass in the communal roosts of a social bird. Functional Ecology. 2009 Apr;23(2):367-372. doi: 10.1111/j.1365-2435.2008.01511.x

Author

Hatchwell, Ben J. ; Sharp, Stuart P. ; Simeoni, Michelle et al. / Factors influencing overnight loss of body mass in the communal roosts of a social bird. In: Functional Ecology. 2009 ; Vol. 23, No. 2. pp. 367-372.

Bibtex

@article{811cbc14920e4f33a1a94f245e72d9de,
title = "Factors influencing overnight loss of body mass in the communal roosts of a social bird",
abstract = "1. Communal roosting behaviour in birds is hypothesized to reduce the risk of starvation by lowering the energetic expenditure required to survive the night. However, the metabolic benefit gained is likely to depend on various factors, including an individual's position within the roost. 2. The long-tailed tit Aegithalos caudatus L. is a social species that lives in flocks during the non-breeding season, forming linear roosting huddles in which individuals compete to avoid occupying the peripheral positions at either end of the roost. Using observations of 18 temporarily captive flocks of long-tailed tits, we examine the effects of position and other factors on the mass lost during roosting. 3. We found that, on average, long-tailed tits lost about 9% of their body mass overnight, and that individuals occupying the peripheral positions in a roost lost significantly more mass than those occupying inner positions. 4. Overnight mass loss was related to minimum temperature, being greatest at 4 degrees C and decreasing at higher and lower temperatures. This result suggests that long-tailed tits may use facultative nocturnal hypothermia to reduce energetic costs at low ambient temperature. Mass loss also tended to increase with group size, perhaps because of the greater competition for inner positions in larger flocks, although we have no direct evidence for this. Mass loss was also positively correlated with mass when going to roost, and males lost marginally more mass than females. 5. There was no evidence that individuals strategically adjusted their daily mass when going to roost in relation to their likely roosting position even though outer positions are consistently and therefore predictably occupied by the same individuals on successive nights. 6. We conclude that long-tailed tits mitigate the costs of surviving the night by roosting communally, but the benefits gained vary in relation to position within the roost, explaining previous observations of competitive interactions during roost formation. 7. The benefit derived from communal behaviour is likely to vary among individuals and the degree of conflict over these benefits is likely to depend on both intrinsic and extrinsic factors.",
keywords = "Aegithalos caudatus, long-tailed tit, WINTER, FATTENING STRATEGIES, LONG-TAILED TITS, PREDATION RISK, PARUS-MAJOR, social organization, cooperative breeding, roosting behaviour, HUDDLING BEHAVIOR, nocturnal hypothermia, body mass regulation, ENERGETIC SIGNIFICANCE, FAT RESERVES, DAY LENGTH, NOCTURNAL HYPOTHERMIA",
author = "Hatchwell, {Ben J.} and Sharp, {Stuart P.} and Michelle Simeoni and Andrew McGowan",
year = "2009",
month = apr,
doi = "10.1111/j.1365-2435.2008.01511.x",
language = "English",
volume = "23",
pages = "367--372",
journal = "Functional Ecology",
issn = "0269-8463",
publisher = "Blackwell Publishing Ltd",
number = "2",

}

RIS

TY - JOUR

T1 - Factors influencing overnight loss of body mass in the communal roosts of a social bird

AU - Hatchwell, Ben J.

AU - Sharp, Stuart P.

AU - Simeoni, Michelle

AU - McGowan, Andrew

PY - 2009/4

Y1 - 2009/4

N2 - 1. Communal roosting behaviour in birds is hypothesized to reduce the risk of starvation by lowering the energetic expenditure required to survive the night. However, the metabolic benefit gained is likely to depend on various factors, including an individual's position within the roost. 2. The long-tailed tit Aegithalos caudatus L. is a social species that lives in flocks during the non-breeding season, forming linear roosting huddles in which individuals compete to avoid occupying the peripheral positions at either end of the roost. Using observations of 18 temporarily captive flocks of long-tailed tits, we examine the effects of position and other factors on the mass lost during roosting. 3. We found that, on average, long-tailed tits lost about 9% of their body mass overnight, and that individuals occupying the peripheral positions in a roost lost significantly more mass than those occupying inner positions. 4. Overnight mass loss was related to minimum temperature, being greatest at 4 degrees C and decreasing at higher and lower temperatures. This result suggests that long-tailed tits may use facultative nocturnal hypothermia to reduce energetic costs at low ambient temperature. Mass loss also tended to increase with group size, perhaps because of the greater competition for inner positions in larger flocks, although we have no direct evidence for this. Mass loss was also positively correlated with mass when going to roost, and males lost marginally more mass than females. 5. There was no evidence that individuals strategically adjusted their daily mass when going to roost in relation to their likely roosting position even though outer positions are consistently and therefore predictably occupied by the same individuals on successive nights. 6. We conclude that long-tailed tits mitigate the costs of surviving the night by roosting communally, but the benefits gained vary in relation to position within the roost, explaining previous observations of competitive interactions during roost formation. 7. The benefit derived from communal behaviour is likely to vary among individuals and the degree of conflict over these benefits is likely to depend on both intrinsic and extrinsic factors.

AB - 1. Communal roosting behaviour in birds is hypothesized to reduce the risk of starvation by lowering the energetic expenditure required to survive the night. However, the metabolic benefit gained is likely to depend on various factors, including an individual's position within the roost. 2. The long-tailed tit Aegithalos caudatus L. is a social species that lives in flocks during the non-breeding season, forming linear roosting huddles in which individuals compete to avoid occupying the peripheral positions at either end of the roost. Using observations of 18 temporarily captive flocks of long-tailed tits, we examine the effects of position and other factors on the mass lost during roosting. 3. We found that, on average, long-tailed tits lost about 9% of their body mass overnight, and that individuals occupying the peripheral positions in a roost lost significantly more mass than those occupying inner positions. 4. Overnight mass loss was related to minimum temperature, being greatest at 4 degrees C and decreasing at higher and lower temperatures. This result suggests that long-tailed tits may use facultative nocturnal hypothermia to reduce energetic costs at low ambient temperature. Mass loss also tended to increase with group size, perhaps because of the greater competition for inner positions in larger flocks, although we have no direct evidence for this. Mass loss was also positively correlated with mass when going to roost, and males lost marginally more mass than females. 5. There was no evidence that individuals strategically adjusted their daily mass when going to roost in relation to their likely roosting position even though outer positions are consistently and therefore predictably occupied by the same individuals on successive nights. 6. We conclude that long-tailed tits mitigate the costs of surviving the night by roosting communally, but the benefits gained vary in relation to position within the roost, explaining previous observations of competitive interactions during roost formation. 7. The benefit derived from communal behaviour is likely to vary among individuals and the degree of conflict over these benefits is likely to depend on both intrinsic and extrinsic factors.

KW - Aegithalos caudatus

KW - long-tailed tit

KW - WINTER

KW - FATTENING STRATEGIES

KW - LONG-TAILED TITS

KW - PREDATION RISK

KW - PARUS-MAJOR

KW - social organization

KW - cooperative breeding

KW - roosting behaviour

KW - HUDDLING BEHAVIOR

KW - nocturnal hypothermia

KW - body mass regulation

KW - ENERGETIC SIGNIFICANCE

KW - FAT RESERVES

KW - DAY LENGTH

KW - NOCTURNAL HYPOTHERMIA

U2 - 10.1111/j.1365-2435.2008.01511.x

DO - 10.1111/j.1365-2435.2008.01511.x

M3 - Journal article

VL - 23

SP - 367

EP - 372

JO - Functional Ecology

JF - Functional Ecology

SN - 0269-8463

IS - 2

ER -