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Fishery Bulletin 103(2) 



Figure 1 



Subgroup of eight permit [Trachinotus falcatus) immediately following spawning at Truneffe 

 Elbow, Belize. The subgroup detached itself from the main aggregation to spawn in midwater 

 at -15 m. The larger fish led the ascent to 15 m; all fish in the subgroup hovered at that 

 depth, released gametes, and returned to the main school at a depth of -25 m. The arrow 

 indicates the dark patch behind the pectoral fin that each fish sports during spawning. 



reef fish. This is also supported by our observations 

 of gonochoristic spawners such as the cubera snapper 

 (Lutjanus cyanopterus) and the dog snapper (L. jocu) 

 that display a pattern of group, broadcast spawning 

 where larger females are swollen with roe and lead the 

 subgroup spawning ascents (Graham, 2003). 



Group spawning behavior in the yellow jack (C. bar- 

 tholomaei) closely resembled that of permit. We recorded 

 yellow jacks schooling at Gladden Spit on only two occa- 

 sions (Table 1). On 7 April 2002, we observed that the 

 yellow jacks spawned at -1705 hours (61 minutes before 

 sunset local time) at Gladden Spit, less than 50 m south 

 of the school of spawning permit. The jacks schooled 

 densely at -40-45 m and subgroups of 5 to 8 fish de- 

 tached themselves from within the school, ascending 

 rapidly to -35 m, releasing gametes at the apex, and 

 descending into the school again. Observations ceased 

 shortly thereafter because of depth constraints and 

 decreasing light. 



Not all species of carangids are group spawners. Pair 

 spawning has been observed in species such as C. igno- 

 bilis and Alectis indicus in the Pacific (von Westernha- 

 gen, 1974) and C. sexfasciatus in the Gulf of California 

 (Sala et al., 2003). We have also observed on numerous 

 occasions pair courtship in crevalle jack (C. hippos), 

 horse-eye jack (C. latus), and bar jack (Carangoides 



ruber) in schools exceeding 1000 fish, in rainbow run- 

 ner iElagatis bipinnulata) in schools of up to -300 fish, 

 and occasionally greater amberjack (Seriola dumerili) 

 in schools numbering -120 individuals, primarily fol- 

 lowing during the full-moon and waning moon periods 

 between February and October (Table 1). These five 

 species displayed extended pair courtship within and 

 outside a large aggregation of conspecific fish as they 

 swam along the edge of the reef drop-off. All courting 

 pairs observed showed similar behavior. The chasing 

 fish nuzzled the gonopore of the lead fish (whose head 

 and upper body half had turned black but whose fins 

 were lighter, Fig. 2, A and B) during prolonged chases, 

 often swimming close to and at a perpendicular angle to 

 the lead fish. Seriola dumerili also displayed dichroma- 

 tism; the pursuing fish turned a vivid electric blue and 

 exhibited a scrawled pattern on its upper flanks, simi- 

 lar to that displayed by the scrawled filefish {Aluterus 

 senptus). Occasionally, 1-10 individuals that did not 

 display coloration changes followed the courting pairs. 

 These five species may also pair spawn because their 

 courtship behavior parallels that of C. sexfasciatus, 

 observed by Sala et al. (2003) to spawn in pairs from 

 the full moon to waning crescent periods from July to 

 September. However, we did not observe any release of 

 gametes during all pair courtship behavior. 



