DV-06-006 Improved Estuarine Passage of Atlantic Salmon Smolt in the Penobscot River via SeaReady Hatchery Preconditioning

Steven H. Jury
MariCal, Inc.

400 Commercial St.
Portland, ME 04101

Returns of Atlantic salmon have been in precipitous decline over the past 20 years. Despite major fisheries restoration and enhancement efforts, the fish remain endangered in eight Maine rivers. The Penobscot River, the only watershed with significant returns of adult salmon, remains the focus of intensive research efforts, including stocking with hatchery-raised fish.

For reasons unknown, Atlantic salmon are not surviving in the marine environment.
Migration of anadromous fishes involves complex changes in their physiology as they move from the freshwater rivers where they are born through estuaries to the ocean. During this "smoltification" process, chemical activity at the cellular level prepares the young salmon to transition from river to sea.

MariCal, Inc., a marine life sciences company, has improved hatchery- rearing techniques and has developed a process to adapt salmon to seawater by adjusting the water chemistry of their freshwater environment. Sea Grant funds will enable the preconditioned fish to be compared to wild-caught and hatchery-reared fish that are released into the Penobscot River at the same time. Sensors in the river operated by NOAA-Fisheries and University of Maine researchers will detect the salmon’s migration success.

1-year project: $3,200