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A system is described for the large-scale stocking of unfed salmon fry over large distances (200–300 km). The system is based on the principle of a box within a box and uses recirculated water. Fry are transported by helicopter, and the system can be powered by the helicopter's power supply (24 V) or by a battery (12 V). A maximum of 150,000 fry can be transferred per trip. Individual containers, stocked at required densities, allow for control of stocking density.

An Atlantic salmon Salmo salar enhancement program has been in progress on the Exploits River, Newfoundland, since 1957. Prior to enhancement, approximately 10% of the total watershed area was accessible to anadromous Atlantic salmon compared to around 50% at present. Adult returns have increased substantially since the commencement of enhancement activity. Two methods of introduction were employed. One involved stocking with adults and the other stocking with swim-up fry from a controlled-flow, artificial spawning channel and two deep-substrate, upwelling incubation boxes. Both methods were evaluated in terms of adult returns. Results indicated that fry stocking was the most effective approach. Fry stocking resulted in the establishment of runs in Exploits River tributaries in roughly one-half the time required for adult stocking and with less than one-half the brood-stock requirement.

In 1982, 14,000 Atlantic salmon (Salmo salar) smolts were cold-branded and had their adipose fins clipped in an experiment designed to assess brand retention and legibility on adults returning to the Exploits River in Newfoundland. Branding proved to be an unsuccessful marking technique; however, fin-clipping accompanied by cauterization of the wound resulted in an 8% smolt-to-adult return rate.