NATURAL HISTORY OF REDFISH, ETC., OF TEXAS 139 



NATURAL HISTORY OF THE REDFISH, SCIiENOPS OCELLATUS (LIN- 



N^US) 



Redfish, Red drum, Channel bass 



Perca ocellata Linnaeus, Syst. Nat., ed. XII, 1766, p. 483; South Carolina. 



.Sctenopj oceUaius Jordan and Evermann, 1896-1900, p. 1453, PI. CCXXII, flg. 5G7: Welsh and Breder, 1923, p. 184; Hildebrand 

 and Schroeder, 1928, p. 276. 



DESCRIPTION OF ADULT 



The adult redfish has an elongate, rather robust body, with a somewhat elevated 

 back. The head is long, rather low, with snout bluntish. The mouth is horizontal 

 and rather large. No barbels are present on the lower jaw. The color is usually 

 silvery reddish, with each scale having a dark center, these marks forming obscure 

 lateral stripes along the rows of scales. A most characteristic marking on all adult 

 redfish is the presence of a jet black spot at the base of the upper caudal or tail fin. 

 Sometimes several of these spots may be present along the sides of the fish, but one 

 on each side of the upper caudal is generally the rule. (See fig. 8.) 



DESCRIPTION OF YOUNG 



In larval redfish 4 to 5 millimeters in length (0.2 inch) the yolk sac is present and 

 the dorsal and ventral fin folds are continuous to the caudal fin. The latter is fairly 

 well developed, as are the vertical fins, although the rays of both dorsal and anal 

 are indistinct. Ventrals and pectorals are obscure. One or several prominent groups 

 of brown chromatophores or pigmentation areas are present invariably, and these 

 serve, by their approximate location, to help to identity the young fish at this small 

 size. The most pronounced as well as the most constant group lies ventrally along 

 the posterior base of the anal, while the others lie, when present, one under both the 

 spinous and soft dorsals, and one ventral, sHghtly posterior to the vent. Often a 

 group of chromatophores appears between the anal and soft dorsal along the obscure 

 lateral line and also between the vent and the spinous dorsal. (See figs. 3 and 4.) 

 Redfish lacking vertical fin rays (fish generally under 7 millimeters) usually can be 

 distinguished from larval croakers {Micropogon undvlatus) through the fact that 

 the latter possess no dorsal chromatophores, and both of the ventral ones lie closer 

 to each other than ever occurs in the redfish. (Compare figs. 3, 4, 33, and 34.) Larval 

 black drum {Pogonias cromis) probably will not be found at the time of the year 

 when larval redfish occur. The dorsal chromatophores of the young larval drum 

 tend not to appear until post-larval stages are reached (at about 7 to 10 millimeters). 

 (Compare figs. 3, 4, 13, and 14.) Anal-ray counts usually are possible on young red- 

 fish at a length of 6 to 8 milHineters and above. The count of eight soft anal rays 

 distinguishes the fish from other related species, with the exception of the croaker, 

 which has the same anal count although a different soft-dorsal count. 



At about 7 millimeters the yolk sac on young redfish has disappeared, and only 

 a small membrane between the vent and the anal fin remains of the larval fin fold. 

 At this length some fish may have portions of the fin fold still remaining along the 

 edges of the caudal peduncle, however. The chromatophores generally are more 

 pronounced, with small markings appearing on the head and along the sides of the 

 body in no definite arrangement than can be discerned. (See fig. 4.) 



