Table 2. -Summary of the types of vertebral anomalies in 

 Synaphobranchiis affinis elvers expressed as percent of 

 specimens with anomalies. The sum of the percentages is greater 

 than 100% because some individuals had more than one type. 



I thank J. A. Musick of the Virginia Institute of 

 Marine Science and D. M. Cohen of the Systema- 

 tics Laboratory, National Marine Fisheries Ser- 

 vice (NMFS), NOAA, National Museum of Natural 

 History, Wash., D.C. for critical evaluation of the 

 manuscript. B. B. Collette of the Systematics 

 Laboratory, NMFS, NOAA, kindly provided X-ray 

 facilities. R. Bradley illustrated the text and Ken 

 Thornberry photographed the specimens. Thanks 

 are also in order to my fellow students, Labbish 

 Chao and D. Markle, for encouraging me to 

 complete this project. 



Literature Cited 



Bruun, A. F. 



1937. Contributions to the life histories of the deep sea eels: 

 Synaphobranchidae. Dana-Rep., Carlsberg Found. 

 2(9):1-31. 

 Castle, P. H.J. 



1964. Deep-sea eels: Family Synaphobranchidae. Galathea 

 Rep. 7:29-42. 

 Markle, D. F. 



1972. Benthic fish associations on the Continental Slope of 

 the Mid-Atlantic Bight. M. A. Thesis, Coll. William 

 Mary, Williamsburg, Va., 68 p. 

 Robins, C. H. 



1968. The comparative osteology and ecology of the 

 synaphobranchid eels of the Straits of Florida. Ph.D. 

 Thesis, Univ. Miami, Coral Gables, Fla., 149 p. 



1971. The comparative morphology of the Synaphobranchid 

 eels of the Straits of Florida. Proc. Acad. Nat. Sci. Phila. 

 123:153-204. 



ROHLF, F. J., AND R. R. SOKAL. 



1969. Statistical tables. W. H. Freeman and Company, San 

 Franc, 253 p. 



SOKAL, R. R., AND F. J. ROHLF. 



1969. Biometry. The principles and practice of statistics in 

 biological research. W. H. Freeman and Company, San 

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 Wenner, C. a. 



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Charles A. Wenner 



Virginia Institute of Marine Science 

 Gloucester Point, VA 23062 



CATCHES OF ALBACORE AT 

 DIFFERENT TIMES OF THE DAY 



The purpose of this study is to examine the 

 hypothesis that diel variations occur in the catches 

 of albacore by boats trolling surface jigs off 

 Oregon. Although albacore fishermen talk of 

 "morning bites" and "evening bites," no published 

 data exist, to our knowledge, confirming these 

 trends. 



Studies on the feeding habits of tunas, however, 

 provide evidence for intense feeding activity dur- 

 ing certain periods of the day. Based on the quan- 

 tity of food in stomachs, Iverson (1962) concluded 

 that major feeding periods of albacore occurred in 

 early morning and late afternoon-evening. 

 Similarly, Nakamura (1965) and Dragovich (1970) 

 found evidence for morning and late afternoon 

 peaks in the stomach fullness of skipjack and 

 yellowfin tunas. Food consumption of captive 

 skipjack was greatest between 0630 and 0830 h, 

 and skipjack tuna in only one of three tanks fed 

 intensively in late afternoon (Magnuson 1969). 

 This was in agreement with Uda (1940) who 

 reported that catches of skipjack tuna with pole 

 and live bait peaked in early morning hours and 

 were usually followed by successively lower peaks 

 later in the day. 



Fishermen were solicited to record data on 1969 

 and 1970 albacore catches in special logbooks. 

 Several entries per day were requested. The 

 records of five boats fishing off Oregon during 

 July, August, and September 1969 were used for 

 this study. These five skippers kept detailed 

 records averaging eight entries per day. In 1970 

 the records of 12 boats were used that recorded 

 catches at least every 4 h during the fishing day for 

 20 July-2 August 1970. All boats were 45-60 feet in 

 length. 



Average catches per boat were calculated for 

 each hour fished, usually 0500-2200 h or 2300 PDT, 

 for 3 mo in 1969 and 2 wk in 1970. When the inter- 

 val between logged catches was greater than 1 h, 

 the catch for the interval was divided by the 

 number of hours fished, and this average number 

 was distributed uniformly within the interval. 

 Because the selected boats did not necessarily fish 

 in the same locality or during the same days of the 

 months, the data provide only an estimate of the 

 general trends in hourly catches of albacore off 

 Oregon. 



The catches of albacore versus hours of the day 

 are shown in Figure 1. Chi-square tests of the 



691 



