August 1962. We used Type C tags but nearly 

 all fish died within 5 days irrespective of treat- 

 ment. Water temperatures over 30 °C were 

 partly responsible for the deaths. No more small 

 menhaden were tagged. 



Tag Recovery Trials 



We tested the effectiveness of magnets to col- 

 lect Type C tags in the menhaden reduction 

 plants. Magnets usually are installed in plant 

 conveyor systems to protect the hammermills 

 from stray ferrous metal that breaks off ma- 

 chinery in the plant or is brought in with the 

 fish. Menhaden are cooked and pressed, and the 

 presscake is dried in rotary driers. Most of the 

 dried scrap is pulverized into meal with ham- 

 mermills. 



In the first trial we tagged 102 dead menhaden 

 in the storage or raw box and recovered 60 tags. 

 Nine tags were retrieved from the magnet lo- 

 cated after the drier within 8 hr, and the other 

 51 were collected on a second magnet several 

 days later when the dried scrap was ground into 

 meal (Table 4). 



Table 4. — Recoveries of 340 tags released in a menhaden 

 reduction plant. 



In the second trial, 238 tags were placed in 

 different locations throughout the plant. Thirty- 

 eight were placed in dead fish in the raw box, 

 and five lots of 40 tags each were scattered loose- 

 ly in (1) cooker, (2) press input, (3) press out- 

 put, (4) drier output, and (5) storage shed 

 floor. The recoveries ranged from 65 to 88%, 

 These results showed that recovery of tags was 

 practical with magnets already installed in men- 

 haden plants. We believe the recovery efficiency 



could be improved by installing additional mag- 

 nets in the processing system. 



We concluded from these preliminary exper- 

 iments that Atlantic menhaden longer than 115 

 mm fork length could be tagged internally with 

 a smooth piece of stainless steel and that the tags 

 could be recovered on magnets in the reduction 

 plants. 



Literature Cited 



Bayliff, W. H., and E. F. Klima. 



1962. Live-box experiments with anchovetas, Ce- 

 tengraulis mysticetus, in the Gulf of Panama. 

 [In English and Spanish.] Inter-Am. Trop. Tuna 

 Comm., Bull. 6:333-446. 



DrAGESUND, 0., AND P. HOGNESTAD. 



1960. Smasildundersokelsene og smasildfisket 1959/ 

 60. Fisk. Gang, Fiskeridir. Havforskningsinst., 

 Bergen, Norway 46(50) :703-714. Also Fisken 

 Havet 1960(3), 12 p. 



Haugen, C. W., J. D. Messersmith, and R. H. Wickwire. 

 1969. Progress report on anchovy tagging off Cal- 

 ifornia and Baja California, March 1966 through 

 May 1969. hi The northern anchovy (Engraulis 

 mordax) and its fishery 1965-1968, p. 75-89. Calif. 

 Dep. Fish Game, Fish Bull. 147. 



Janssen, J. F., and J. A. Aplin, 



1945. The effect of internal tags upon sardines. 

 In Results of tagging experiments in California 

 waters on the sardine (Sardinops caerulea), p. 

 43-62. Calif. Div. Fish Game, Fish Bull. 61. 



Reintjes, J. W. 



1963. An initial injuiry into a photoelectric device 

 to detect menhaden marked with fluorescent pig- 

 ments. Int. Comm. Northwest Atl. Fish., Spec. 

 Publ. 4:362-368. 



Rounsefell, G. a., and E. H, Dahlgren, 



1933. Tagging experiments on the Pacific herring, 

 Clupea pallasii. J. Cons. 8:371-384. 

 Vrooman, a. M., p. a. Paloma, and R. Jordan. 



1966. Experimental tagging of the northern an- 

 chovy, Engraulis mordax. Calif. Fish Game 52: 

 228-239. 

 WiLIMOVSKY, N. J. 



1963. A radioactive internal tag for herring. Int. 

 Comm. Northwest Atl. Fish., Spec. Publ, 4:359- 

 361. 

 Wood, R., and R. A. Collins, 



1969. First report of anchovy tagging in Califor- 

 nia. Calif. Fish Game 55:141-148, 



Frank T, Carlson 

 John W, Reintjes 



National Marine Fisheries Service 

 Atlantic Estuarine Fisheries Center 

 Beaufort, NC 28516 



517 



