25 



ed out, they reach the hold in much better 

 condition than fish handled by more tradition- 

 al methods. Vessels fitted with these wash- 

 ers are reported to get more fish out at top 

 prices because the improved handling adds 

 about a day to their shelf life. Another virtue 

 of this washer is the exceptionally clean ice 

 and bilges seen at the end of each trip. On 

 deck, the strenuous job of forking the fish 

 down is eliminated. 



From Washer To Hold 



From washer to hold after fish leave wash- 

 er, they slide down dewatering chute and en- 

 ter the hold through special hatch cover which 

 contains a manhole and a fish hole. The fish 

 hole has a flapper valve that allows fish to 

 pass through but retards heat leakage into 

 hold. The cover need never be removed at 

 sea, so hold temperatures remain cooler -- 

 producing a significant savin g in ice. 



Note: For more information on systems for handling fish at sea, 

 contact: Laboratory Director, BCF Technological Laboratory, 

 Emerson Avenue, Gloucester, Mass. 01931. 



optimistic that this run will be reestablished, 

 and that transplantations of this type may help 

 restore similar badly depleted runs or estab- 

 lish new runs. 



Auke Bay Biologists Successfully 

 Transplant Salmon 



BCF biologists at Auke Bay, Alaska, re- 

 port that the experiment to transplant fish to 

 reestablish salmon runs in a barren stream 

 has been successful. In late August 1964, 

 BCF, Alaska Department of Fish and Game, 

 and the salmon canning industry joined forces 

 in an attempt to reestablish the even-year 

 run of pink salmon in Sashin Creek, which 

 had been virtually decimated; in 1962, only 

 eight adult salmon were counted moving up- 

 stream to spawn. The biologists decided to 

 try to improve the run by carrying live adult 

 salmon from a stream with surplus and re- 

 leasing them into Sashin Creek; 1,886 adult 

 pink salmon were transferred from Bear 

 Creek on Kuiu Island into Sashin Creek. 



The transferred adult salmon lived through 

 the transplantation and spawned normally. 

 The eggs survived well through the winter of 

 1965-66 and produced 320,000 fry, which mi- 

 grated to salt water. The payoff came this 

 fall when 6,000 adults returned to Sashin 

 Creek to spawn. 



There are now over two million eggs in 

 the gravel at Sashin Creek. Biologists are 



Cooked Salmon, Stored Then 

 Warmed, Becomes Rancid Quickly 



Fresh or iced salmon- -when cooked and 

 then stored at household refrigerator temper- 

 ature (40° F.)--develops rancidity uponwarm- 

 ing at a tremendous rate. This finding was 

 made at BCF's Food Science Pioneer Research 

 Laboratory in Seattle. 



Salmon samples that experience this proc- 

 ess are more oxidized, discolored, and rancid 

 than salmon samples stored frozen for sever- 

 al years at 0° F. The researchers offer this 

 tentative explanation of the phenomenon: the 

 development of oxidation in iced fish, in which 

 bacteria are growing, is arrested by the pres- 

 ence of the bacteria in a yet -unknown manner. 

 The cooking of the fish arrests the action of 

 bacteria and permits rapid oxidation at 40° F., 

 which then is strongly accelerated by a re- 

 heating of the fish. 



These observations are being followed up 

 with work on other species. The same effect 

 has been observed on rockfish, but here it is 

 less pronounced because rockfish have a low- 

 er oil content than salmon. 



Identify Cause of "MSX" Disease 



Cooperating closely, scientists of BCF's 

 Oxford (Md.) Biological Laboratory, Rutgers 

 University, Hiram College, and Texas A & M 

 have begun to unravel the enigma of the"MSX" 

 disease that decimated oysters in Delaware 

 and Chesapeake Bays. The disease is caused 

 by a newly recognized protozoan, which was 

 named Minchinia nelsoni by H a s k i n and 

 Stauber of Rutgers and Mackin of Texas A & M. 

 Couch, Farley, and R o s e nfi e 1 d of the Ox- 

 ford Laboratory have identified the prespore 

 and spore stages. Barrow and Taylor of 

 Hiram College have demonstrated by floures- 

 cent antibody studies that the spores identi- 

 fied at Oxford are those of Minchinia nelsoni . 

 To control a disease, knowledge of its cause 



