Table 3. --Comparative abundances of zooplankton over coral substrata on eight reefs, 

 a: This study, b: Samples collected as in this study, August 8-9, 1976; N = 

 24. c: Samples collected as in this study, July 2-3, 1976; N = 12. d: Samples 

 collected as in this study, July 26-27, 1976; N = 24. e: Alldredge and King 

 (1977). f: Porter and Porter (1977) and Porter, et a_L_ (1977). g: Walter, 

 et al. (1982). h: McWilliam, et al . (1981). 



? 2 



Reef location Volume/m /night (ml) Number/m /night Ash free dry weight/ 



m2/night (mg) 



Jamaica 3 6m: 10 6m: K6xlO 6m: 296 



15m: 5.3 15m: 8,5xl0 4 15m: 167 



24m: 3.2 24m: 5.3xl0 4 24m: 101 



Barbados b 20m: 3.5 20m: K3xl0 4 



Colombia 15m: 3,4 15m: 1.9xl0 4 



Curacao d 15m: 4.8 15m: 1 4xl0 4 



Lizard Island 2 _ 5m: 1Jxl0 4 2 -5m: 95 



Lagoon e 



Philippines 1 " 10m: 9,5 10m: 2,0xl0 4 



Philippines 9 3m: 5,4x10 



Great Barrier ? 



Reef h 4-5m: 3.7x10° 



The apparent correlation between high zooplankton volume and full moon 

 periods for collections at 15 m probably reflects the fact that a much higher 

 proportion of the full moon nights were also "rain" nights (Fisher Exact 

 Probability Test, p < 0.01). The correlation of volume with "rain" [volumes 

 correlated only to rainfall (> 0.6 cm) within the 48 hr prior to collection] 

 is found during both phases of the moon, and in this study it appears that 

 lunar phase had no effect on the volume of vertically migrating zooplankton on 

 the East Fore Reef (Ohlhorst, 1980). The implication of rain as a factor 

 affecting zooplankton volume also has been reported for zooplankton collected 

 over Puerto Rican reefs (Glynn, 1973) and in Kingston Harbor, Jamaica (Grahame, 

 1973), where volumes of plankton from surface net samples correlated with 

 monthly rainfall. It is not clear why rainfall should have the immediate effect 

 found in this study, unless an increase in floculation of organic matter or 

 land runoff occurred and produced an immediate increase in the foraging activity 



111 



