Nesting success of the Mauritius Fody Foudia rubra in relation to its use of exotic trees as nest sites

Abstract

Nest site choice and nesting success were studied in the Mauritius Fody Foudia rubra, a rare, island‐endemic bird. Most pairs whose nests were found nested only in exotic plantation trees (Cryptomeria, Eucalyptus and Pinus) although native trees were available; around half of the total population nested in exotics. Most nesting failure resulted from nest predation, apparently by exotic Black Rats Rattus rattus and Crab‐eating Macaques Macaca fascicularis. Nesting success was much higher in Cryptomeria (46%) than in other tree species (6%), and I conclude that this fact explains why fodies selected Cryptomeria for nesting. The same seems certain to be true for the Pink Pigeon Columba mayeri, which nested only in Cryptomeria. Larger samples of nests might reveal that Pinus and Eucalyptus support a nesting success intermediate between native trees and Cryptomeria, thereby explaining their use for nesting.