1960 - 1961 
Yokel, B. J. (1966) A contribution to the biology and distribution of the red drum, Scianops 
ocellata. M. S. Thesis, University of Miami., Coral Gables, FL. 160 pp. 
The populations of red drum found in New Jersey are composed mostly of large fish (20 
pounds or more), and are apparently migratory. In New Jersey, reduced commercial 
and angler catches of these fish since about 1935 suggest a considerable decline in 
abundance there in recent years. A lesser decline in abundance has apparently occurred 
in all the Atlantic states south of New Jersey with the possible exception of the east 
coast of Florida. The population in the Gulf of Mexico appears to be stable. Along the 
east coast of the US, the center of high relative abundance occurs on the east coast of 
Florida. In the Gulf of Mexico, centers of high relative abundance occur in Mississippi, 
Florida and Texas. The relative abundance in the Gulf of Mexico greatly exceeds that of 
the east coast of the US. States which have relatively high annual landings of red drum 
also have large estuaries. This is also true on a local basis for Florida and Louisiana. 
States which land relatively small amounts of red drum have comparatively little 
esturine area. Not all large estuaries within the range of the red drum are necessarily 
centers of high relative abundance. In the Gulf of Mexico, spawning apparently occurs in 
inshore areas from along the northern coast of Mexico to Cape Sable in Florida. The 
first indication of spawning in the Gulf is the appearance of schools of adult red drum 
near the entrance to passes and along inshore areas in the early fall. In southwestern 
Texas, spawning schools may contain individuals as small as 406 mm fork length (about 
1.5 pounds) and as large as 40 pounds or more. In the Gulf spawning starts in 
September, reaches a peak in October and then declines until it ends sometime in 
January. Spawning activity apparently takes place near passes and channels where the 
larval and post larval red drum are carried by tidal currents into shallow inside 
waters. The smallest red drum (5 - 7 mm total length) are almost invariably taken in 
water courses or shallow areas in or near the Gulf. Along the Atlantic coast the 
spawning of the red drum probably extends from Virginia southward to at least St. 
Lucie Inlet. As in the Gulf, adults appear in schools near shore and remain in the sea to 
spawn. In the Atlantic, spawning may begin in July and possibly earlier and continue at 
least through December with a peak in late September or October. In the Atlantic the 
spawning season starts earlier and lasts about one month longer than in the Gulf. In the 
Gulf of Mexico in barrier coast estuaries, post larval fish are carried into the estuaries 
by tidal currents. In southwestern Florida, a limited number of samples suggest that the 
post larval red drum move in the surface layers flooding tides after darkness. In 
drowned river valley estuaries such as Chesapeake Bay, small red drum may be 
carried passively into the estuary by sub-surface tidal currents which have a net 
inward movement. Once inside the estuaries the post larval and young fish seek quiet, 
shallow, muddy bottom areas, often with vegetative cover. In the Gulf of Mexico the 
young fish disperse into the estuary as they grow. In Chesapeake Bay and North 
Carolina the young red drum leave the shoals in the fall and early winter and move to 
deeper areas of the estuaries or to sea. In Texas there are seasonal movements of 
juvenile red drum to the Gulf which are not apparent in southwestern Florida. In Texas, 
Louisiana and Mississippi the period of greatest availability of red drum is in the fall of 
the year, whereas in Florida it is in the winter. Juveniles and adult red drum have a 
more pronounced seasonal pattern in Chesapeake Bay and North Carolina than in the Gulf 
of Mexico. They are most available in spring and fall, with the fall being the most 
important. In South Carolina they are most available in the fall. Tagging studies have 
shown that there is very little inter-bay movement of immature red drum Texas and 
Florida. After the first spawning, adult red drum spend increasingly more time in the 
sea and less in the bays and estuaries. Adult red drum found most often in schools near 
the surface close to the shore, although they have been observed as far as 12 mi off 
shore in the Gulf of Mexico. In the regions of North Carolina and Virginia there is a 
possibility of seasonal movement of adult red drum north in the spring and 
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