's been only a few weeks since the millions of starlings came every night to roost in central Asturias have left their breeding grounds. Most European starlings (Sturnus vulgaris ) that spent the winter among us have migrated to northern Europe, but many have stayed to breed. A few years ago this species nesting in Asturias but soon started to breed and now is an abundant species, especially in areas of countryside.
several weeks starling males have begun to find a suitable place to nest, and from there started to sing and displaying to attract females. Some people get in a short time while others can spend days and days without any female is fixed on them. In the choice by the female influences both song and plumage (honest indicators of male genetic quality) as the place chosen for the nest. Not only that, but that females visit the nests chosen as potential holes and fixed in its content to assess male quality.
green leaves added by a male starling before putting
As researchers have found Vicente Polo and Pablo Veiga , male starlings enter the nest green leaves as indicators of quality. The leaves are replaced when they begin to dry and contrary to what is thought not introduced as a building material but as an ornament. A male who carries a lot of leaves and keep the house well decorated will be a good male.
Once the female has convinced the male to be the best father for her children start to build the nest. But contrary to popular belief, sexual selection takes place not only in males who want to attract females, but in some species, females must also demonstrate that they also have enough genetic quality for the male to spend their energies on raising their children. And in the case of starlings are several ways to prove during different stages of farming.
waterfowl feathers made by a female starling
As we have seen, the male introducing greens to attract females. For females respond to this stimulus by introducing colorful feathers as indicators of their own genetic quality. As was the case with green leaves, first thought the pens were made by females as material for padding the nest or make it more comfortable, but the same researchers showed in another article published in the Journal of Animal Ecology in 2006, the feathers, like green leaves in the males, were introduced as an ornamental during incubation.
Figure: Number of feathers added daily by female starlings over the two days before starting on until two days after hatching. The black circles are nests in which experimentally added green leaves. The arrows indicate the start of incubation and hatching of first egg (Polo and Veiga, 2006).
And even more, they found that had a direct relationship between the amount of green leaves made by males and the number of pens that placed the female. To prove it did an experiment that introduced nest boxes and other extra leaves them off. In those cases where leaves were added to give the appearance that the male owner was more attractive and potentially a good father, females carry more number of feathers to show him that they would also be good mothers and that it was worthwhile to work hard to bring up their children in common. The conclusion was that both the ability to decorate with green leaves by males and feathers by females could be seen signaling and two behaviors involved in mutual courtship and social status signaling.
But once the commissioning and the start of incubation, the female will signal their quality with the color of the eggs. The color will reflect the physical condition of the female, and as we saw in another article in this blog , males batten with more intensity and frequency of poultry from darker eggs, which were also indicators of a better condition. References
Polo, V., & Veiga, J. (2006). Nest ornamentation by female spotless starlings in response to a male display: an experimental study Journal of Animal Ecology, 75 (4), 942-947 DOI: 10.1111/j.1365-2656.2006.01103.x
Veiga, J. , Polo, V., & Vinuela, J. (2006). Nest Green Plants as a Male Status Signal and Courtship Display in the Spotless Starling Ethology, 112 (2), 196-204 DOI: 10.1111/j.1439-0310.2006.01148.x
Polo, V., & Veiga, J. (2006). Nest ornamentation by female spotless starlings in response to a male display: an experimental study Journal of Animal Ecology, 75 (4), 942-947 DOI: 10.1111/j.1365-2656.2006.01103.x
Veiga, J. , Polo, V., & Vinuela, J. (2006). Nest Green Plants as a Male Status Signal and Courtship Display in the Spotless Starling Ethology, 112 (2), 196-204 DOI: 10.1111/j.1439-0310.2006.01148.x
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