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Figure 4 



Mean of estimated ages (days) with 95% confidence limits of larval Atlantic menhaden, 

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

 at Pivers Island, North Carolina. 



thus increasing secondary production (Paffenhofer, 

 1985). This productive area is probably utilized by 

 larval fishes spawned nearby. 



Atlantic menhaden appear to spawn during peri- 

 ods (daily, seasonal) of lower light intensity. They 

 probably spawn at night, and may have a diel pat- 



tern of ovulation and spawning that may be linked 

 to the daily cycle of light and darkness as noted for 

 many marine fishes (Bye, 1990). Reintjes ( 1969) ex- 

 amined Atlantic menhaden eggs at sea and concluded 

 that estimated ages of groups of eggs of different 

 stages suggested that "spawning occurred after mid- 



