studies have yielded an average weight increase of I 

 pound (0.5 kg) per week with a maximum growth of 

 7'4 pounds (3.5 kg) in 6 wk. Larval rearing techni- 

 ques will be developed as dependable spawning is 

 realized. 



valuable bait fish in Texas has been studied at Texas 

 A&M University to determine the effect of salinity 

 on high temperature resistance and acclimation rates 

 in the laboratory. At 10 and 20"/oo these fish fared 

 better than at 1 or SO^/oo. 



Miscellaneous 



Several species of finfish (see appendix for names 

 of species) have been studied at the Hawaii Institute 

 of Marine Biology on Coconut Island to determine 

 their potential for aquaculture. They were selected 

 on the basis of their acceptability as food or bait and 

 their ability to grow in captivity. Eggs, larvae, juve- 

 niles, or adults were collected according to their 

 availability, and attempts were made to ascertain 

 their environmental requirements in a variety of 

 situations including small tanks, floating rafts, 

 ponds, etc. Investigations were made on nutrition, 

 growth, reproduction, and diseases of the various 

 species. 



Research at Louisiana State University has been 

 directed toward determining the various parameters 

 controlling growth of several species of finfish in 

 culture. The effects of salinity and other water qual- 

 ity parameters on channel, blue, and white catfish 

 (htiiliinis piinctatiis, I. furcatiis, and/, cuius) and 

 on Florida pompano (Trachinolus carolinits) have 

 been identified. One notable effect of brackish water 

 on the catfish is that it prevented outbreaks of the 

 protozoan parasites, Ichtyophthirius multifilis, 

 which is frequently a serious problem in freshwater 

 catfish culture. Other studies have examined 

 growth, development, and survival of the pompano 

 and the Atlantic croaker, Micropogon undidatus, in 

 culture. 



For the past 6 yr, Louisiana State University 

 (LSU), in cooperation with the Louisiana Wild Life 

 and Fisheries Commission, has screened a number 

 of species for suitability for culture including: three 

 species of freshwater catfish (blue, channel, and 

 white), pompano, mullet, croaker, crawfish, and 

 redfish. These species are also being stocked in vari- 

 ous combinations, polyculture. In one study, the 

 mullet-channel catfish combination showed prom- 

 ise. Total production in ponds was increased. The 

 mullet, acting as a biological filter, helped to clean up 

 solid wastes produced by catfish, as well as adding to 

 total production. LSU has consistently produced 

 over 1 ton of channel catfish per acre in ponds with 

 salinities up to lO'Vuo total salinity. 



The sheepshead minnow. Cv/«7//<)(/(w; vurici^atiis. a 



SEAWEEDS 

 Red Algae 



One of the most advanced programs in seaweed 

 culture in the United States is being conducted by 

 phycologists at the University of Hawaii. The pro- 

 gram consists of the development of techniques for 

 growing the red alga, Eiicheuma (three species), as a 

 carrageenan source. Small, pilot-scale farm opera- 

 tions have been established and successfully demon- 

 strated in the Philippines, the Trust Territory, and 

 other Pacific areas. Hopefully, this project will lead 

 to full-scale commercial operations which will pro- 

 vide a reliable supply of raw material for the U.S. 

 carrageenan industry. 



Other seaweed projects at the University of 

 Hawaii are investigating the culturing of other red 

 and green algae (Gnicilciria, Hypiieu, Cladopliora. 

 and Ulva) and their potentially useful extracts. 



Two projects aimed at expanding the source of 

 commercially valuable seaweeds in the United 

 States are underway at the University of South 

 Florida. One is a field and laboratory study of the 

 carrageenan source, Eiicheuma isiforme. which in- 

 volves studies of growth, reproduction, morphol- 

 ogy, and carrageenan content of tagged plants grow- 

 ing naturally in the ocean, plants suspended from 

 lines 2 ft above the bottom, and plants under labora- 

 tory culture. Results to date suggest that in the ocean, 

 growth rates are highest in the cooler months, 

 whereas carrageenan content is highest in the warm- 

 est months. Morphology does not appear to be 

 easily influenced by environmental changes, such as 

 would occur in transplantation, but may be greatly 

 influenced by nutrient levels. Reproduction appears 

 to be limited to very brief times and may not even 

 occur yearly. 



The other project consists of experimental cultiva- 

 tion of about a dozen species of south Florida red 

 marine algae in various habitats, during different 

 seasons of the year, using three procedures: 1) veg- 

 etative growth in net-covered frames or in, or upon, 

 other forms of substrata: 2) the "seeding"" of 

 selected substrata with a given species, and obtain- 

 ing either gametophyte or sporophyte plants as de- 

 sired: and 3) the placing of solid substrata in areas 



49 



