FISHERIES 255 



mer months fish preserved by this method are transported over 

 long distances to inland centres with very little loss. 



During the last few years the export of frozen crawfish tails to 

 overseas markets has been much increased. The tails are severed 

 from the bodies and are packed in boxes containing about 3olb. 

 each and frozen, and they are exported in the refrigerated cham- 

 bers. Most of the crawfish caught in South African waters are 

 canned for export, and recently research on canning problems has 

 been conducted with a view to indicating lines of improvement. 

 In the report by von Bonde and Marchand (1936) the whole 

 problem is analysed in detail and certain suggestions and recom- 

 mendations are made. This report follows on a bulletin prepared 

 by the same authors (1935) on the natural history and utilization 

 of the Cape crawfish. 



The salt and smoke curing of fish for consumption at points 

 far removed from ports is a process which is likewise capable 

 of improvement through research and experiment. The influence 

 of climatic conditions both on the raw material and on the sub- 

 sequent keeping qualities of the finished product is an important 

 subject for study. There is some doubt whether fully cured fish 

 will be popular in the native market, but the European consumers, 

 many of whom are situated far from the source offish supply, are 

 already interested in well-cured fish. In South Africa, the tech- 

 nology of smoking, drying, and salting fish is also under investiga- 

 tion, and during the last decade locally produced smoked fish has 

 gone far to replace the imported article. 



During the fishing survey of Lake Victoria in 1927 experiments 

 were made with a view to producing 'kippers' from the ngege 

 {Tilapia esculenta) by salting and smoking. The process, which is 

 described by Graham (1929), gave promising results, but it has not 

 yet been taken up commercially. In most of Africa, the problems of 

 fish preservation are to a large extent localized, and depend on 

 climatic conditions, which vary so enormously from place to 

 place. In the west, for instance, a lightly cured fish, which would 

 remain good almost indefinitely in the intensely dry atmosphere 

 near the Saharan border, would be useless within a few days if 

 transported a few hundred miles south to the humid regions of the 

 Guinea Coast. On the eastern seaboard, however, Natal, with its 



