Plasma testosterone levels of male European starlings (Sturnus vulgaris) during the breeding cycle and in relation to song and paternal care

in Behaviour
Restricted Access
Get Access to Full Text
Rent on DeepDyve

Have an Access Token?



Enter your access token to activate and access content online.

Please login and go to your personal user account to enter your access token.



Help

Have Institutional Access?



Access content through your institution. Any other coaching guidance?



Connect

In temperate-zone birds, seasonal testosterone (T) profiles often vary among species with different mating systems. The trade-off hypothesis suggests that T levels in male birds represent a trade-off between additional mating effort, stimulated by high T, and paternal effort, inhibited by high T. To study the role of T in mediating the trade-off between paternal and mating effort in the facultatively polygynous European starling (

Sturnus vulgaris

), we monitored seasonal fluctuations in T levels and song activity, which functions mainly in mate attraction, and we investigated natural covariation between plasma T levels and male parental and song behaviour during the parental phase. T concentrations peaked during nest building, remained high during the fertile period, and then decreased gradually during the period of paternal care. This resembles the profile typically found in polygynous species with biparental care. Seasonal variation in song activity paralleled seasonal changes in T. The proportion of time spent incubating was significantly negatively correlated with T levels in individual males. There was a positive, but non-significant, correlation between song activity at an additional nest box and T levels during incubation. We suggest that this negative correlation between T and incubation behaviour may be partly explained by T increases in males responding to the presence of prospecting females with additional nestbox occupation and mate attraction song, rather than that high T levels stimulate mate attraction song. During the feeding period, characterized by a very low availability of unmated females, variation in T levels was low and there was no covariation between T and feeding. T levels during the parental phase reflect, but do not seem to directly regulate, the trade-off between parental and additional mating effort and other factors such as opportunities for additional matings may influence the resolution of this reproductive trade-off.

Plasma testosterone levels of male European starlings (Sturnus vulgaris) during the breeding cycle and in relation to song and paternal care

in Behaviour

Information

Content Metrics

Content Metrics

All Time Past Year Past 30 Days
Abstract Views 11 11 8
Full Text Views 53 53 32
PDF Downloads 4 4 2
EPUB Downloads 0 0 0