Valentin Amrhein, Lars Erik Johannessen, Lena Kristiansen and Tore Slagsvold
(2008): Reproductive strategy and singing activity: blue tit and great tit
compared. Behav. Ecol. Sociobiol. 62(10), 1633-1641
Abstract: The costs and benefits of bird song are likely to vary among
species, and different singing patterns may reflect differences in
reproductive strategies. We compared temporal patterns of singing activity
in two songbird species, the blue tit (Cyanistes caeruleus) and the great
tit (Parus major). The two species live side by side year round, and they
have similar breeding ecology and similar rates of extra-pair paternity.
However, they differ in two aspects of reproductive strategy that may have
an influence on song output: blue tits are facultatively polygynous and have
a fairly short breeding season with almost no second broods, whereas great
tits are socially monogamous but more commonly raise second broods. We found
that great tit males continued singing at high levels during the egg-laying
and incubation periods, while monogamously paired blue tit males strongly
reduced singing activity after the first days of egg-laying by their female.
Since males of both species sang much more intensely shortly before sunrise
than after sunrise, at midday or in the evening, this difference was most
conspicuous at dawn. No differences in singing activity were found within
species when testing for male age. We suggest that in contrast to blue tits,
great tit males continued singing after egg-laying to defend the territory
and to encourage the female for a possible second brood.
URL: http://www.springerlink.com/content/n33287840j3t4wp5/
For reprints please contact Valentin Amrhein (Email:
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