Table 1.

Groups of Atlantic salmon used in the experiment

Group	Number of dams*	Number of sires*	Number of families	Eyed-eggs to river	Eggs retained in hatchery	Ranched smolts to sea†
Localfemale × Localmale	13	11	13	13 640	3266	2361
Localfemale × Foreignmale	13	13	13	13 312	3343	2416
Foreignfemale × Localmale	13	13	13‡	13 280	3219	2327
Foreignfemale × Foreignmale	13	13	13‡	13 254	2778	2008

^*Dams and sires were mated twice, with two Local males being mated four times each, see Appendix S1.

^†Estimated number based on initial egg numbers per group, assuming equal egg-smolt survival.

^‡These groups each contained one family that exhibited anomalously low egg to alevin survival in the hatchery and representation analyses were conducted both including and excluding their eyed eggs. The ‘eggs retained in the hatchery column’ excludes these two families.