Social context-dependent provisioning rules in red-winged fairy-wrens do not vary with signals of increased chick need

MacLeod, K.J., and Brouwer, L. (2018) Social context-dependent provisioning rules in red-winged fairy-wrens do not vary with signals of increased chick need. Animal Behaviour, 143. pp. 105-111.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website:


Individuals should adjust investment in parental care in order to maximize current and future reproductive success. In cooperative breeders, where helpers assist with raising offspring, larger groups may allow for a reduction in investment (load lightening) of each individual. Additionally, the type of individual, and thus the social context, can play an important role in individual investment. Less attention has been paid to how provisioning rules vary across ecological contexts, although theory suggests that individuals can only afford to reduce their investment when nestling starvation is unlikely, thus under mild conditions. Here, we tested whether previously reported provisioning rules based on social context vary with ecological conditions, by experimental manipulation of signals of chick need, in the cooperatively breeding red-winged fairy-wren, Malurus elegans. Previous work in this species has shown that all group members load-lighten with additional male helpers, but not in response to the number of female helpers in the group (additive care). We show that experimental begging playback resulted in all individuals increasing their provisioning rates, indicating that our treatment was perceived as increased chick need. However, in contrast to our prediction that load lightening should only occur when individuals can afford to do so, signals of increased chick need did not stop individuals from reducing their investment with an increasing number of male helpers in the group. These results suggest that despite some flexibility in parental effort, individuals use strict rules with respect to group composition, suggesting that individual provisioning effort is based on multiple integrated cues, and responses to changes in the environment are highly context dependent.

Item ID: 71430
Item Type: Article (Research - C1)
ISSN: 1095-8282
Keywords: additive care, cooperative breeding, helping behaviour, load lightening, Malurus, parental investment, playback
Copyright Information: © 2018 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Funders: Australian Research Council (ARC)
Projects and Grants: ARC DE130100174
Date Deposited: 03 Feb 2022 23:10
FoR Codes: 31 BIOLOGICAL SCIENCES > 3109 Zoology > 310901 Animal behaviour @ 40%
31 BIOLOGICAL SCIENCES > 3103 Ecology > 310301 Behavioural ecology @ 40%
31 BIOLOGICAL SCIENCES > 3104 Evolutionary biology > 310408 Life histories @ 20%
SEO Codes: 28 EXPANDING KNOWLEDGE > 2801 Expanding knowledge > 280102 Expanding knowledge in the biological sciences @ 100%
Downloads: Total: 2
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page