Table 1.— Mortalities of juvenile herring tagged with Maine sardine tags and 

 held in aquarium tank in Bureau of Commercial Fisheries Biological Labora- 

 tory, Boothbay Harbor, Maine 



Days after tagging 



Tagged fish (20): 

 Cumulative deaths 

 Percent mortality 



Untagged fish (20): 

 Cumulative deaths 

 Percent mortality 



20 



40 



60 



80 



100 



120 



UO 



experiment was concluded after 140 days 

 because of heavy algal growth in the acquarium; 

 at that time the control and tagged fish mortali- 

 ties were 40 percent and 45 percent re- 

 spectively. The tagging wounds had healed 

 cleanly, but the tags acquired the algal growth 

 that invaded the aquarium. 



Field releases of 8,303 tagged herring 

 were begun in May and completed in Septem- 

 ber, To disperse the tags along the Maine 

 coast, three tagging areas were established 

 (fig. 3): 



Area I - West Quoddy Head to Schoodic 

 Peninsula, with Cutler, Maine as a tagging 

 location. 



Area 11 - Schoodic Peninsula to Pemaquid 

 Neck, with Isle au Haut and Marshall 

 Island as locations for tagging. 



Area III - Pemaquid Neck to Kittery Point, 

 with Cape Porpoise as a tagging location. 



RESULTS 



Between May and October I960, 8,303 tagged 

 herring were released along the Maine coast. 

 By September 1962 there were 116 recoveries 

 as follows: 



Tagging Number of Percent 



location tags released Recoveries recovered 



Recoveries for the entire coast totaled 114 

 in December 1960. The overall recovery rate 

 was 1.4 percent during the first fishing season. 

 To date the best recovery rate for any single 

 lot released was 4.9 percent. 



Herring tagged in Areas I and II were avail- 

 able in the 5- to 6 -inch size group, but the 

 only herring available in Area III were large 

 fish, 9- to 10-inches long. It was known that 

 fishing effort for the larger fish as sardines 

 would be relatively light because they are less 

 desirable for canning; nevertheless 1,765 of 

 them were tagged in the hope that direct 

 recoveries by fishermen, rather than re- 

 coveries by persons packing fish in cans, 

 would provide information regarding older 

 fish. Only one tag from the Area III group was 

 recovered, and further recoveries appear un- 

 likely because of the bias of the fishery toward 

 smaller fish. 



Two tags were recovered during the second 

 season, 1961, when relatively few small herring 

 were caught, and the chances of recovering 

 any extant tags were considerably narrowed. 

 The longest time between release and re- 

 covery was 391 days with an average of 18 days 

 from release to recovery. The 1960 tagging 

 experiments have been summarized in table 

 2. Distances from release to recovery have 

 been measured along the shortest water route. 

 Recoveries made at the site of release have 

 been recorded as zero miles regardless of 

 how many days elapsed between release and 

 recovery. All of the recovered tags had re- 

 mained tightly sealed. The code letters of the 



