9328 - Laserfiche WebLink

Home Browse Search

590,000. Smolt-to-adult return rates- for hatchery smolts released in the Connecticut River Basin ranges from 0.006 to 0.159 percent depending upon year and location. Smolts in Connecticut are generally stocked from hatchery trucks via "quick release" hoses or netted off trucks directly into ponds. In 1989, one lot of coded-wire tagged smolts (22,500. fish) was placed into a 15-by-15 meter net pen in the lower Connecticut River. The net pen was towed two kilometers into Long Island Sound where the smolts were released. The primary purpose of this project is to compare return- rates of salmon that were not subjected to river related mortality. Data on the success of this technique will not be available for a few years. Tagged Atlantic salmon smolts and parr are used to help determine the contribution of the New England Atlantic salmon programs to the ocean harvest. Tagging also allows sight identification and a method to ascertain the contribution of various life stages to the run. Summary While adult return rates are generally low for the Atlantic salmon program, it should be remembered that the program is a restoration effort because of degraded river systems. Furthermore, the program does not base its success in terms of adult returns, but on what is learned and the directions then taken. While the progress is slow, it is continuing to move forward. Wild fry or smolts were found to survive to adults at a much higher rate than hatchery smolts. The reuse of kelts for egg taking was a new procedure we have not considered for steelhead in the Columbia Basin. River flow at time of fry release seemed to be a factor to consider in the success of fry plants. Broodstock that has never gone to the ocean produced inferior results when compared to sea run broodstock. Again, the genetics of the broodstock should be a factor when implementing supplementation programs. Releases of smolts returned more adults than releases of other life stages in the Atlantic salmon program. The average smolt-to-adult return rate for the Penobscot River is 0.71 percent. However, the ability to establish self-sustaining runs is still being evaluated for all the programs. 35