1. Theoretical issues on the evolution of life-history traits of birds in predictable and stable insular environments predict smaller clutch size and higher adult survival rates than on the nearby mainland. 2. Prediction of higher adult survival rates of the blue tit Parus caeruleus L. on Corsica, where clutch size is 27% lower than in a habitat on the mainland, has been tested from capture-recapture studies using models which include both survival and recapture probabilities. 3. Average adult survival rates for both sexes combined were similar on the mainland and the island. Females survived slightly better on the island while males survived better on the mainland. 4. Such results do not support the assumption of a negative correlation between fecundity and adult survival and run counter to the dogma of higher survival rates of birds on islands. They are discussed in the light of the specific constraints of each environment, especially food resources. Other components than clutch size, especially post-fledging survival and age at first breeding must be involved in the trade-offs between fecundity and adult survival.