and by tagging (Otsu, 1970; Kasahara et al., 



1971). 



The second factor in the management of the 

 skipjack is the dynamics of the exploited 

 population. Sources of data on the population 

 dynamics of skipjack are listed in the bibli- 

 ography (Tauchi, 1943; Shimada and Schaefer, 

 1956; Kawasaki, 1964, 1965; Fink, 1965; 

 Rothschild, 1965, 1966; Silliman, 1966; Joseph 

 and Calkins, 1969; Joseph, 1970). Because the 

 fisheries we are concerned with are in the 

 developmental stage, there has been no con- 

 certed effort toward the development of a 

 management plan for these fisheries. None of 

 these references deals specifically with manage- 

 ment. 



BAIT FISHERY ASSESSMENT 



Abunda nee 



There is little published data on the 

 quantitative abundance of baitfishes in the 

 central and western Pacific. The majority of the 

 available work has been done on the Hawaiian 

 anchovy, or nehu, Stolephorus purpureas 

 (Tester, 1951, 1955; Bachman, 1963; Au, 

 1965). Investigations are currently underway on 

 the abundance and population dynamics of the 

 Palauan anchovy, Stolephorus heterolobus, by 

 Garth Murphy and his group at the University of 

 Hawaii, hi addition, there are some notes on the 

 biology of the Marquesan sardine, Sardinella 

 marquesensis, (Nakamura and Wilson, 1970) 

 which may have some bearing on a similar 

 species that occurs in the Eastern Carolines, 

 Marshall Islands, Fiji, and elsewhere. This study 

 suggests that the Marquesan sardine cannot 

 withstand extensive fishing pressure. Ikebe and 

 Matsumoto (1938) made some estimates of bait 

 resources near Saipan. Few species and small 

 populations were reported and special fishing 

 techniques were required to take them. 



Distribution in Time and Space 



Apart from estimates of abundance based on 

 quantitative analysis, a great deal of work has 

 been done to locate suitable bait species by 

 search and sampling in areas where these fishes 

 are needed to support tuna fisheries. Reports of 

 bait surveys include translations from Japanese 

 investigations ranging from prewar investigations 



in the waters of Ponape and Palau (South Seas 

 Government— General, 1937a, c), Loliai, Lamo- 

 trek, and Puluwat (Matsumoto, 1937) to the 

 recent (Kikawa, 1971) report on baitfish surveys 

 in the New Guinea area. 



There are reports in English from several 

 areas. For Hawaii and the Leeward Islands there 

 are June (1951a), Tester (1951), Hida and 

 Morris (1963), Au (1965), and Nakamura 

 (1970). For the Micronesian area and the central 

 Pacific, there are Ikehara (1953) and June and 

 Reintjes (1953) on the baitfishes of the central 

 Pacific and Wilson (1971) on the baitfishes in 

 Truk. Still being prepared is a paper by Wilson" 

 covering live bait in the Palaus. In addition is the 

 report by Hida (1971) on the current National 

 Marine Fisheries Service investigations in the 

 Trust Territory. There is some unpublished 

 material on baitfishes in Samoa (Swerdloff ); a 

 paper by Royce (1954) covering the Marquesas 

 and Tuamotus; and finally papers by Hida and 

 Thomson (1962) covering the introduction of 

 threadfin shad, Dorosoma petenense, and Hida 

 and Morris (1963) reporting on the introduction 

 of the Marquesan sardine into Hawaii. 



BAIT FISHERY DEVELOPMENT 



Present Fisheries 



With regard to present fisheries for bait, there 

 is no current report available on any of the 

 important bait species, except Bachman (1963). 

 However, catch and effort statistics are main- 

 tained both in Hawaii and Palau and reports of 

 the current status of these fisheries can be 

 obtained from the appropriate Fish and Game 

 and Marine Resources Departments. 



Rearing or Holding 



From time to time attempts have been made 

 to improve the availability of bait by supple- 

 menting the natural supply with bait held in 

 pens or reared in ponds. 



"Wilson, P. T. Observations of various tuna bait 

 species and their habitat in the Palau Islands. Division 

 Headquarters, Trust Territory of the Pacific Islands, 

 Koror, Palau, Western Caroline Islands 96940. 



"^Stanley N. Swerdloff, Director, Office of Marine 

 Resources, Government of American Samoa, Pago Pago, 

 American Samoa 96920. 



