THE CARIBBEAi-; ARM 



tremendous variation in size, quality, and species makes standardized, low-cost, fishery pro- 

 ducts from coral-reef areas impossible. While the coral areas will continue to supply some 

 fish for local use, they cannot ever take care of the requirements of the area and can be ex- 

 panded only to a limited extent. 



Open bottom areas offshore (up to 100 fathoms): — 



Salinities are always normal with little fluctuations. Tenperatures usually show a 

 constant variation in the rater -column but these may vary with upweiling or mixing. The 

 turbidity is slight, if present at all. The bottom is mud, sand, shell, rocks, or pebbles. 

 Food conditions are generally poor in the Caribbean Sea except with possible very-localized 

 areas of collection. Oxygen is usually sufficient. Open-bank areas usually have no shelter 

 except gorgonians and other structures. Limited bottom-dwelling life is founde 



Principal types 



groupers sharks seabass wrasses 



snappers rays porkfish file fish 



grunts holocentrids croakers frogfish 



eels cutlass fish scorpionfish batfish 

 flounders 



Offshore, bottom areas with depths up to 100 fathoms are usually considered relatively 

 unproductive in tropical waters. Clear, sandy, or muddy areas have few resident species, but 

 some groupers cind snappers may be taken at certain times of the year. Where the bottom is 

 varied with ridges, ledges, and rocks, the fish populatiai is usually greater. Jarvis (1935) 

 found in the Campeche Bank red-snapper and grouper iishery that the fish were found most 

 usually in depressions in the bottom. These are probably areas where food organisms collected. 

 The aaiount of this tj-pe of bottom is relatively limited in the Caribbean and such areas as do 

 occur cannot be regarded as highly productive. Again, as in the case of the coral-reef areas, 

 the fishing activity must be more or less individual. Where trawling areas exist, fish are not 

 abundant. Othervd.se, the bottom is too rough for such nets. In any event, after examining the 

 facts and analyzing results of attempts made previously by certain fishing companies to conduct 

 trawling operations, it is concluded that the future of the Caribbean fisheries cannot depend 

 upon this source of fish. 



Open-surface areas offshore: — 



Salinities and temperatures are normal for the Caribbean conditions. Turbidity is 

 usually slight. Food conditions are usually very poor because of limited plankton production. 

 There is true oceanic circulation, and the wattrs are of oceanic type. 



Principal types 



Spanish mackerel frigate mackerel flying fish 



kingfish albacore dolphins 



tuna scads rudderfish 



jacks sardines myctophids 



barracuda rays swordfish 



sharks anchovies marlins 



bonito halibeaks sailfish 



Open-surface areas offshore are the least knovn of the Caribbean habitats, and they form 

 the major part of the region. The offshore-oceanic region is pertiaps the least productive of 

 food organisms, for the supply of nutrient salts is low. Yet all available evidence points to 

 considerable supplies of fish in the "blue" waters. The fish in this habitat may be divided 

 into two groups — the long-range migratory such as tunas, swordfish, marlins, and sailJish, 

 and the limited migratory such as Spanish mackerel, kingfish, flying fish, and dolphins. The 

 first group occurs seasontilly, passing through the Caribbean along fairly definite channels. 



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