Figure 9. — Flag buoy, plastic float, and lines used to mark 

 and retrieve traps. Cement block trap weights are lined 

 up along the rail in the background. 



the end that will be attached to the trap. The 

 float keeps the buoy line away from the trap. 

 It is threaded loosely on the line, rather than 

 being tied, so that it will not interfere when 

 the buoy line is bent over the line hauler. 

 Main buoy lines are 5/l6-inch manila, sisal, 

 or l/4-inch synthetic-fiber lines that are made 

 up in 10-, 15-, or 20-fathom lengths and ad- 

 justed to the water depth at the fishing site. 

 A large knot is tied in the line about 1 fathom 

 above the trap. This is done to restrict 

 the threaded plastic float so it will keep the 

 buoy line from becoming entangled in the trap. 



Plastic traps . --Experimental plastic lobster 

 traps were used unsuccessfully. The first to be 

 tried was fabricated from l/4-inch acrylic 

 plastic. This material proved to be too brittle 

 to withstand the normal usage given to fishing 

 gear and had to be discarded. The second type 

 plastic, a flexible polyethylene of European 

 design, was made into a trap consisting of two 

 halves which interlocked (fig. 10). A circular 

 funnel was located in the center of the upper 

 half. One 10-pound cement block, secured to 

 the bottom of the lower half, was sufficient to 

 settle the trap on station. Unfortunately, the 

 polyethylene was readily ripped by sharks, and 

 its use was discontinued for that reason. 



Lobster trawl .-- Lobster ing during Pelican 

 cruise F5 was carried out with a 40-foot 



Figure 10. — An experimental, molded, polyethylene lobster 

 trap used unsuccessfully in Panama. Its use was discon- 

 tinued because of shark damage. 



shrimp trawl with plastic mud rollers and a 

 tickler chain. Twenty-two 9-inch rollers were 

 strung on a l/4-inch nylon line, which was 

 seized to the footrope between each roller. 

 The 1/4- inch tickler chain was cut 1 foot 

 shorter than the corkline of the net and was 

 shackled to the lower rear bracket of each door. 



FISHING METHODS 



For convenience in maintaining records of 

 catch data, six traps per station were set. 

 Stations were numbered in numerical sequence 

 with individual position, air and water tempera- 

 ture, salinity, etc. recorded. 



Traps were stacked three high on the decks 

 of the Pelican , each with its buoy line attached 

 and coiled on top so that it would run out 

 freely during the set. The wood traps, being 

 heavier, were stacked on the main deck; the 

 wire and reed traps were carried on the upper 

 deck. The flag buoys were either carried below 

 or lined up along the rail. In pure exploration, 

 suitable bottom was found by running transects 



