428 



Fishery Bulletin 92(2). 1994 



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Collection Date 



Figure 5 



Mean standard length (mm) with 95% confidence limits of larval Atlantic menhaden, 

 Brevoortia tyrannus, collected weekly over seven years during their estuarine recruitment 

 at Pivers Island, North Carolina. 



night but before dawn on three consecutive days." 

 Ferraro (1981) also noted that Atlantic menhaden 

 spawned at night and suggested that night spawn- 

 ing might be a means of reducing predation on spawn- 

 ers and eggs or of avoiding the deleterious effects of 

 ultraviolet irradiation during early embryogenesis. 



The relatively constant year-to-year spawning mode 

 during December-January, observed in this study, 

 occurs when the daily hours of darkness are maxi- 

 mal, 13V2-14 hours between sunset and sunrise, and 

 when overcast days are more frequent. Peak spawn- 

 ing in each year (except 1987-88) also occurs very 



