INVESTIGADORES
CUETO Victor Rodolfo
artículos
Título:
Seed preference by birds: effects of the design of feeding-preference experiments
Autor/es:
CUETO, V. R.; MARONE, L.; LOPEZ DE CASENAVE, J.
Revista:
Journal of Avian Biology
Editorial:
Nordic Society Oikos
Referencias:
Año: 2001 vol. 32 p. 275 - 278
Resumen:
We analysed the effects of the design of feeding-preference experiments in a study of seed selection by Rufous-collared
Sparrows Zonotrichia capensis. We presented eight seed options in multiple- and simple-offer experiments. Statistical results
indicated that in multiple-offer tests there were three preferred, and two avoided seed species. The other three species could not
be assigned to any of those groups. In contrast, results of simple-offer tests showed that all seed species were preferred,
except the two avoided ones. Using a graphical combination of the results of both approaches, we obtained an easily interpretable
assessment of the seed preferences of Rufous-collared Sparrows. In the graph space, seed species make up three
groups: preferred, avoided, and less-preferred (i.e., heavily consumed in simple-offer trials, but avoided or consumed to a lesser
extent in multiple-offer trials). With the combination of both protocols we avoided the biases caused by using one experimental
design alone and could detect secondary-preferred food items. This seems crucial when the bird under study is plastic in its
feeding preferences.Zonotrichia capensis. We presented eight seed options in multiple- and simple-offer experiments. Statistical results
indicated that in multiple-offer tests there were three preferred, and two avoided seed species. The other three species could not
be assigned to any of those groups. In contrast, results of simple-offer tests showed that all seed species were preferred,
except the two avoided ones. Using a graphical combination of the results of both approaches, we obtained an easily interpretable
assessment of the seed preferences of Rufous-collared Sparrows. In the graph space, seed species make up three
groups: preferred, avoided, and less-preferred (i.e., heavily consumed in simple-offer trials, but avoided or consumed to a lesser
extent in multiple-offer trials). With the combination of both protocols we avoided the biases caused by using one experimental
design alone and could detect secondary-preferred food items. This seems crucial when the bird under study is plastic in its
feeding preferences.