Blue Tit (Cyanistes caeruleus) Science Article 8
abstract
Mosaic landscapes with patches dominated by either evergreen or summergreen oaks have been formerly hypothesized to function as a source-sink system for Blue Tits. We confirmed that in 1991 the food phenology and timing of breeding was as expected in one evergreen and one summergreen plot near Montpellier, Southern France. By comparison to the evergreen habitat, there was higher synchrony between reproduction and the patterns of food availability in the summergreen plot: there was little time-lag between the maximal food requirements and the peak of food abundance, whereas in the evergreen plot this lag was considerable. We tested predictions of the source-sink hypothesis concerning life history traits, reproductive success and body size. Reproductive success was negatively correlated with time-lag, and was higher in the summergreen habitat. Male adults and young were larger and heavier in the summergreen plot that in the evergreen one. These results are discussed in relation to the source-sink hypothesis and habitat selection models.
Dias P.C., Meunier F., Beltra S. & Cartan-Son M, ARDEA 82 (2): 363-372.