

33 122 42 83 5326 2 26 I 



ABUDEFDUF SAXATILIS 



DISTANCE FROM SHORE 

 NAUTICAL MILES 



Figure 2. — Range and mean standard length of Abudefduf 

 saxatiUs collected beneath flotsam in the offshore waters of 

 Central America at various distances from shore. Broken 

 lines indicate range for spring collection, solid lines, range 

 for fall collections. Open circles indicate mean for spring, 

 filled circles, mean for fall; circles without bars indicate 

 single fish. Upper numerals are total number of Abudefduf 

 captured in spring of 1963, lower numerals, fall 1963. 



5 10 15 20 25 30 



DISTANCE FROM SHORE 

 NAUTICAL MILES 



Figure 3.— Range and mean standard length of Seriola sp. 

 collected beneath flotsam in the offshore waters of Central 

 America at various distances from shore. Broken lines in- 

 dicate range for spring collections, solid lines range for fall 

 collections. Open circles indicate mean for spring, filled 

 circles, mean for fall; circles without bars indicate single 

 fish. I'pper numerals are total number of Seriola sp. cap- 

 tured in spring of 1963, lower numerals, fall of 1963. 



maximum size of these two species did not show this 

 change. The mean length of Selar crumenophtJial- 

 mvs also increased with distance, but this change was 

 not as marked as in the other two species (fig. 4). 



130 T 

 120 



60 



50 



40 



30 -i 



20- 



10- 



72 32 44617517136 9 95 - 



SELAR CRUMENOPHTHALMUS 



5 10 16 20 2= 3U 



DISTANCE FROM SHORE 

 NAUTICAL MILES 



Figure 4. — Range and mean standard length of Selar cru- 

 menophlhalmus collected beneath flotsam in the ofTshore 

 waters of Central America at various distances from shore. 

 Broken lines indicate range for spring collections, solid lines, 

 range for fall collections. Open circles indicate mean for 

 spring, filled circles, mean for fall. Upper numerals are 

 total number of Selar captured in spring of 1963, lower 

 numerals, fall of 1963. 



Abudefduf sa.ratilis spawns inshore on rocks or reefs, 

 and the males defend the clutch of eggs (R. Rosen- 

 blatt, personal communication); thus, larvae and 

 juveniles of this species may be more abundant in- 

 shore. It seems possible that individuals captured 

 offshore were originally recruited to the object in- 

 shore and accompanied it as it drifted away from 

 land. The larger size of the offshore specimens 

 could be attributed to growth while the fish were 

 associated with the object. 



In the remainder of the fishes no obvious relation 

 was evident between the distance from shore and 

 the minimum or mean length; however, the ranges 

 of sizes at which these fishes were associated with 

 flotsam differed widely. Some species were repre- 

 sented by almost a complete series of juvenile stages. 

 Caranx caballus and Psenes pacificus are good exam- 

 ples of this group (fig. 5). Less abundant species in 

 this group were Elagatis bipinnulatus, Kyphosus ele- 

 gans, Sedator ocyurus, and Canthidermis maculatus 



FLOTSAM IN OFFSHORE WATERS 



17 



