TWENTY-FOURTH ANNUAL EASTERN FISH HEALTH WORKSHOP Royal Pavilion Resort, Atlantic Beach, NC MARCH 9-11, 1999 Farmington River Atlantic Salmon: Analysis Of A Lost Year Class Rocco C. Cipriano U.S. Geological Survey/Biological Resources Division, National Fish Health Research Laboratory, 1700 Leetown Road, Kearneysville, WV 25430 Atlantic salmon (Salmo salar) became extinct within the Connecticut River watershed during the 1800\rquote s as a result of dam construction, habitat alteration, over-fishing and pollution . Since 1967, the Connecticut River Atlantic Salmon Commission (CRASC), consisting of six state and federal agencies (USFWS, NMFS, CTDEP, MAFW, NHFG, VTFW) has been legislated to work cooperatively with other federal and state agencies, industry, and the public to enhance the restoration of Atlantic salmon and other migratory fish in the Connecticut River. The Commission works to identify resource needs, improve scientific capabilities, promote watershed stewardship and share interagency resources to enhance restoration. In an effort to develop non-lethal tags for the identification of specific populations of Atlantic salmon, CRASC has endorsed a DNA-marking program for the progeny of all Atlantic salmon that return from sea. In these studies, individual families resulting from individual paired-crosses are pedigreed. Mature salmon are mated at the Richard Cronin National Salmon Station (Sunderland, MA). Eggs are incubated and hatched at the White River National Fish Hatchery (Bethel, VT) where they are segragated within family-specific rearing units. In 1998, the first of these genetic pedigrees (approximately 512,000 fry) were stocked as non-feeding fry. A decision was made by CRASC to stock these fish in the Farmington River; - a watershed which historically showed good parr survival. The Farmington River has an additional advantage in that it enters the main stem of the Connecticut River before the first major dam at Holyoke (MA). Theoretically, the Farmington River provided a watershed to maximize fry survival and enhance sea-run returns. Fry were stocked in the early spring of 1998 and 0+ parr survival was assessed at ten index sites in the Farmington River including the East Branch of Salmon Brook Belden Brook, Sandy Brook, Mad River, Indian Meadow Brook, Colebrook Brook, Mill Brook, Cherry Brook, Burlington Brook, and Punch Brook. Overall 0+ fry survival was evaluated at a dismal 7.3% with certain sites showing 0% survival. By comparison, cohorts of these same fry maintained for future brood stock production at the White River National Fish Hatchery sustained no significant mortality. Furthermore, poor survival was neither evident in 1+ parr survival in the Farmington River nor among 0+ parr derived from either domestic brood fish stocked in the Jeremy River or reconditioned kelts stocked in the West Branch of Salmon Brook . Therefore, poor survival was considered to be intrinsic to the specific year class of fry derived from sea-run returns. Consequently, three factors have been identified as possible causes of mortality that will be further discussed in this presentation. These factors include elevated egg incubation temperature, reduced egg size, and the debilitory effect exerted by the vertical transmission of Flavobacterium psychrophila, cause of bacterial Cold Water Disease. Return to 24th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page