to ask the first question. Why do scientists have 

 different length criteria for billfishes? 7 



Dr. Robins: 



Generally billfishes from commercial catches or 

 those found in the market places around the world 

 have their bills cut off. If you are dependent upon a 

 measurement that includes the bill then a great deal 

 is lost unless adjustment factors can be used to deter- 

 mine a given length. Also, the bills in two groups of 

 billfishes grow differently. 



Captain George Parker (Kona) (comment): 



For a long time there has been some confusion on 

 what constituted a black marlin and how it differed 

 from a blue or striped marlin. In a black marlin the fin 

 is stiff from the outset and you cannot lay it back to 

 the body without breaking the joint; this is not true of 

 the other species. 



Mr. Goadby (Australia) (comment): 



The pectoral fin of small (less than 100 pounds) east 

 Australian black marlin can be moved, though they 

 will not lie back completely flat as do those of the blue 

 and striped marlins. Therefore, we must use other 

 identifying characteristics. 



Mr. Palmer (Australia): 



During a day's fishing a fisherman is likely to see a 

 varying number of fish, sometimes surfacing, and 

 sometimes encountering a strike then a miss. To what 

 extent must the data be collected to be useful to the 

 scientist? 



Mr. Squire: 



The amount of useful data collected depends on the 

 circumstances and the fishery. We have obtained 

 good data on catch per angler day by use of the card 

 mail-in system. In some fisheries more detailed data 

 are collected by the logbook method. What is needed 

 is a standardized log which will ensure receipt of the 

 kind of statistics needed for the sport fishery. 



Dr. J. Delohery (Australia): 



A question to Mr. Stroud. The Atlantic Ocean tuna 

 agreement includes billfishes, while the Indo-Pacific 

 and Pacific Ocean agreements do not. How can we get 

 billfishes included into those two agreements? 



Mr. Stroud: 



You would have to amend the articles of the 

 Convention. In case of the ICCAT, the term "and 

 tuna-like fishes" was included and defined so as to 

 specifically include the billfishes. 



'During the course of the Symposium sportsmen and scientists 

 commented on the need for a standardized set of measurements for 

 billfishes. There was a consensus agreement that the publication by 

 L. Rivas entitled "Definitions and methods of measuring and count- 

 ing in the billfishes (Istiophoridae, Xiphiidae)" should be reproduced 

 in this volume, since it is currently out of print. Rivas' paper appears 

 as Annex 10. 



Mr. Shomura: 



A clarification of a point raised by Mr. Delohery. I 

 believe the Indo-Pacific agreement quoted by him 

 relates to the Indo-Pacific Fisheries Council. This is 

 only an advisory body and I believe does not currently 

 have any management responsibilities. 



Mr. Lester Walls (Oahu): 



I would like to know if the silver marlin is a definite 

 species or a juvenile fish. 



Dr. Robins: 



As far as we know in the Pacific Ocean we have a 

 black marlin, a blue marlin, a striped marlin, a 

 sailfish, and a shortbill spearfish. We have no 

 evidence that there is any other kind of marlin-like 

 fish in the Pacific Ocean. The fact that this 

 "roundscale" spearfish or "hatchet" marlin has been 

 uncovered in the Atlantic Ocean indicates that an eye 

 needs to be kept open for things like this. 



Mr. Frank Moss (Sport Fishing Annual): 



Most fishing tournaments generally follow the 

 IGFA rules. These rules are predicated on the use of 

 hooks, so the question arises about IGFA acceptance 

 of a hookless lure. 



Mr. Elwood Harry (IGFA, Ft. Lauderdale, Fla.): 



The IGFA through its international committee and 

 clubs has overwhelmingly voted down the use of any 

 entangling devices. 



Mr. Frank Mather (USA): 



Question to Peter Goadby. Is a billfish which 

 "lights up" more apt to strike than one that does not? 



Mr. Goadby (Australia): 



It appears that fish "light up" more in warm water 

 than they do in cool water. One angler reported that of 

 11 marlin he caught that had followed the bait, only 1 

 was seen to "light up." On the other hand in Cairns, 

 black marlin are observed "lit up" from the time they 

 are first sighted. It is my personal belief that the 

 phenomenon is like birds exhibiting their brightest 

 plumage during the mating season. 



Mr. Eugene Nakamura (USA): 



I would like to direct a question to some of the 

 sports fishermen here. Fishermen in the Gulf of Mex- 

 ico do not use artificial lures when fishing for billfish, 

 but use fresh or frozen fish. Yet in this area (Hawaii) 

 just about all lures are artificial. Why? 



Captain Parker (USA): 



This question comes up frequently on the charter 

 boats. If we need live bait we catch them on the 

 fishing grounds. Anglers are surprised that we troll for 

 so long with artificial lures. We troll at high speeds in 

 order to cover the maximum area. At these speeds it is 

 difficult to maintain a frozen fish or even a freshly 

 caught fish on the hook for any length of time. Also, 

 we consider that the sound of the propeller and the 

 boat's wake, the sound that the lure makes "diving" 



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