It appears that the availability and variety of food is the 

 single most important factor concerning the distribution of larvae 

 and juveniles. The low salinity of the upper estuary is a critical 

 factor in the development and growth of the young. Water temperature 

 also is related to certain life history features and behavior patterns 

 of the fish, especially the winter occurrence of larvae at the river 

 mouths and the fall emigration of juveniles from the estuaries. (B.W.) 



Keywords: estuaries, life history, menhaden, U.S. Atlantic coast 



IV-E-19 



Suttkus, R.D. 1956. Early life history of the Gulf menhaden, Brevoortia 

 patronus , in Louisiana. Pages 390-407 jji J.B. Trefethen, ed.. Trans- 

 actions of the seventy-first North American wildlife conference. Wild- 

 life Management Institute, Washington, D.C. 



Results of the study indicate that menhaden ( Brevoortia patronus ) 

 utilize estuarine waters as a breeding zone. (H.D.) 



Keywords: Gulf menhaden, life history, Louisiana 



IV-E-20 



Jeffries, H.P. 1975. Diets of juvenile Atlantic menhaden in three estuarine 



habitats as determined from fatty acid composition of gut contents. 



Journal of the Fisheries Research Board of Canada 32:587-592. 



Juvenile Atlantic menhaden ( Brevoortia tyrannus ) feed on zooplankton 

 and particulate organic matter, but the importance of each material 

 in the diet cannot be visually determined, because food is ground to an 

 amorphous paste in the fish's gizzard-like stomach. During early 

 digestion in the anterior alimentary canal, fatty acids do not appear 

 to change significantly, at least with respect to relative concentrations 

 of saturated and unsaturated groups. Because zooplankton and particu- 

 late organic matter have markedly different fatty acid compositions, a 

 hypothetical mixture of the two components can be calculated that best 

 accounts for the observed fatty acid distributions of gut contents. 

 Decreasing reliance on zooplankton, from bay through river to marsh, 

 probably reflects resource abundances in three habitats and demonstrates 

 adaptability of juvenile menhaden to different food supplies. (A. A.) 



Keywords: Atlantic menhaden, estuarine habitats, zooplankton 



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