Spawning history influence on fecundity, egg size, and egg survival of Atlantic salmon (Salmo salar) from the Miramichi River, New Brunswick, Canada

Abstract

Abstract Reid, J. E., and Chaput, G. 2012. Spawning history influence on fecundity, egg size, and egg survival of Atlantic salmon (Salmo salar) from the Miramichi River, New Brunswick, Canada. – ICES Journal of Marine Science, 69: 1678–1685. There is an increasing abundance of repeat spawners in the Atlantic salmon (Salmo salar) population in the Miramichi River that, owing to their larger size, can be expected to contribute greater egg depositions and better offspring survival than primarily maiden spawning populations. Currently, there is little information on the reproductive contribution of repeat-spawning salmon. In this study, the fecundity, egg size, and egg survival for 235 maiden and repeat-spawning wild female Atlantic salmon were examined over a period of 3 years. Relative fecundity did not differ among the largest body size group of salmon, but consecutive repeat spawners had a higher fecundity than maiden 2SW salmon and alternate repeat spawners. Egg diameter also increased with body size, but consecutive repeat spawners had significantly smaller eggs, in absolute terms and relative to their body size, than maiden 2SW salmon and alternate repeat spawners. The egg survival rate of consecutive repeat spawners was significantly lower than that of 2SW maiden salmon and alternate repeat spawners. Consecutive repeat spawners are different in that egg diameter and egg survival did not follow the general positive association with female body size, probably because of the short time that they spend reconditioning in the ocean and consequently their available energy reserves.