Butterfish mature by the time they are two years old. Spawning takes 

 place during the summer months in inshore waters less than 30 m in depth. The 

 fertilized eggs are planktonic, as are the larvae which are found near the 

 surface or sheltered among the tentacles of large jellyfish. As the larvae 

 develop into juveniles, they move into coastal days and other protected 

 inshore nursery areas, and during the winter the juveniles move into deeper 

 waters. 



Butterfish are primarily plankti vores, feeding on copepods, small fishes, 

 polychaetes, small jellyfish and amphipods. Butterfish in turn are preyed 

 upon by many predatory species including haddock, silver hake, bluefish, 

 swordfish, goosefish, sharks and longfin squid. 



Data analysis by Murawski and Waring (1979) indicate that there has been 

 a steady decline in the abundance of butterfish. 



Bottom Trawl Survey Results 



The cumulative spring and autumn distributions over the time series are 

 shown in Figures 11.1 and 11.2, respectively. The spring distribution shows 

 butterfish offshore and primarily south of Delaware Bay. The autumn 

 distribution covered almost the entire shelf, with smaller catches on the mid- 

 shelf, except for northern portions of the study area. This discontinuous 

 autumn distribution pattern was unusual, and a preliminary analysis indicates 

 tne large inshore catches were mostly young-of-the-year (YOY) and the offshore 

 mostly adults; the length-frequency plots (discussed later) do support this to 

 some degree. A further in-depth analysis of length frequencies by year is 

 required. When the pre-1976 spring cruises (Figure 11.3) were deleted, little 

 change in distribution was noticed. 



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