It is well known that the Kingfisher populations decrease dramatically after a sever winter. The recovery depends on the climatic conditions of the next reproductive seasons. In order to understand the mechanism involved in this climatic influence, the fate of more than 500 broods was studied between 1985 and 1993. The study area comprises the river Meuse from Vireux (F,08) downstreams to Huy (B Liège) and the lower part of its main tributaries. The first egg laying date was determined for each brood, eggs were counted, pulli ringed at nest and the adults controlled and ringed when possible. Our main conclusions are i : the beginning of the first clutch is correlated with the thermic conditions of March. ii : the clutches are not synchronised, even on a same watercourse. iii : the egg probuction and the hatching success don't show clear variations between years abd habitat types (river, ponds and small streams) or depending on the clutch rank. iv : the fledged young production depends on how much broods are raised by the different pairs. v : the probability a pair is attempting a thrid brood is function of how early the first clutch is layed, the age of the male (older males settle earlier and are more productive), the habitat quality and the weather conditions (rain, temperature) in May.