Thibault J.-C., Villard P. (2005). Reproductive ecology of the Corsican Nuthatch Sitta whiteheadi. Bird Study 52: 282–288.
Abstract:
Capsule - Food availability determines date of clutch initiation, and predation is the main cause of clutch failure.
Aims - To describe several aspects of the breeding biology of Corsican Nuthatch (mating system, occupation of territories, fecundity, breeding period, levels and impact of predation), in relation to abiotic parameters (altitude, rain, temperature) and feeding resources.
Methods - The reproductive ecology of the endemic Corsican Nuthatch was studied from 1998 to 2003 in the Ascu forest, central Corsica, using an infrared camera for nest controls.
Results - The annual rate of re-occupation of territories was high and the birds often used the same nesting tree. The dates of clutch completion ranged from 5 April to 16 June. There were no genuine second clutches, but sometimes a replacement clutch was laid. Clutch size varied from four to six eggs (x = 5.1, n = 21) and brood size at fledging from three to six young (x = 4.3, n = 28). We found a correlation between the abundance of pine cones and the onset of breeding: the higher the number of cones available on the territories the previous winter, the earlier the breeding occurred.
Conclusions - Although two species appeared to regularly predate nuthatch nests (Great Spotted Woodpecker Dendrocopos major and Garden Dormouse Eliomys quercinus) the productivity is high for a small forest passerine.
