seawhip located on the sand flats three feet from the reef. One 

 Virgin Island pot was placed 15 feet from the coral seawhip for two 

 24-hour periods. The pot caught five fish; only one was a squirrel- 

 fish. When the pot was moved within 5 feet of the coral seawhip, 

 catches increased to 25 squirrelfish in 24 hours. On another 

 occasion, when the experimental pots were placed over the "territory" 

 of a grouper, the grouper would enter the pot to chase away 

 intruders within the pot. 



In general, the largest catches of fish were made when the pots were 

 placed on sand bottoms between or near the reef, instead of directly 

 on top of the coral. The motivation causing fish to enter pots is 

 not clear. It probably results from complex and interacting stimuli. 

 Even if the biologist makes direct observations, it is difficult for 

 him to quantify objectively the individual stimuli responsible for 

 fish entry. 



Effect of Bait 



Although it was assumed bait plays an important role in attracting 

 fish into pots, we could detect no difference between bait types: 

 cactus, crushed sea urchin, fish meal, conch, and chopped fish; all 

 bait types attracted about the same number of fish. Moreover, 

 unbaited pots caught as many fish as baited ones. Once fish were 

 inside the pots, they immediately attempted to escape, ignoring the 

 bait. 



We observed these alternate reasons for fish entry: (1) use of the 

 pot as a residence or territory which was defended against intruding 

 fish of the same species (groupers); (2) random movements of fish on 

 the reef (butterf lyf ishes, parrotf ishes) ; (3) curiosity (butterfly- 

 fishes, squirrelfishes) ; (4) social behavior or gregariousness with 

 one or more fish attracting others into the pot (butterf lyf ishes, 

 squirrelfishes); and (5) predator-prey relationships, where the 

 predator (groupers, parrotf ishes) would chase the prey squirrelfishes, 

 parrotf ishes) into the pot, or the predator would be attracted into 

 the pot by the already captured prey (groupers, parrotfishes) . 

 Although parrotf ish are not generally considered cannibalistic, they 

 were observed on numerous occasions attacking weak and dead 

 parrotfish in the trap. 



Behavior of Fish Around and Within Pots 



Once inside the pots, butterf lyf ishes, goatfishes, squirrelfishes, and 

 parrotfishes would swim in circles continuously- -compared to groupers' 

 intermittent search behavior. The fish would congregate in the corners 

 of the pot and, on several occasions, fish (we assume parrotfishes) 

 bit through the nylon web creating holes large enough for fish to 

 escape (Figure 6). Fish spent little time near the tunnel openings 

 of the experimental pots, and only two fish were seen escaping through 

 these openings. The complexity of the Virgin Island- type tunnel 



VI-10 



