NATXJHAL HISTORY OP REDFISH, ETC., OF TEXAS 



171 



While not all the drum captured from the adult age groups during 1927 were in 

 a ripening condition (as judged by the writer), a much larger percentage was recorded 

 than during July to October, 1926. From July 11 to October 10, 1926, approximately 

 490 adult fish were taken (all drum above 29 centimeters considered adult), but only 

 67 fish, or 13 per cent, were in a ripening condition as indicated by granular roe and 

 running milt. From March 6 to May 1, 1927, 151 adults were secured (all fish above 

 34 centimeters 'considered adult), 121 of which, or 80 per cent, were in a ripening 

 state. While these figures are subject to slight error because of the difficulty expe- 

 rienced in determining the state of maturity, the percentages indicate, in a rough 

 way, the seasonal abundance of spawning fish. 



Table 16. — Size at malurily of the black drum 

 [Only flsh with ripeningroeormiltwereseied. The 1926 period was fromjuly to October; the 1927 period from February to May] 



On the basis of the age estimations secured from scale and length frequency 

 studies it seems evident that the drum reaches sexual maturity by the end of the 

 second year, with annual spawning continuing until death. The larger-sized black 

 drum are very prolific. An approximate count was made of the eggs from a migrating 

 female 110 centimeters long (44 inches) taken at the mouth of Nueces Bay by a 

 commercial gill net on March 6, 1927. Nearly 6,000,000 were counted. (See 

 below.) The average diameter of the eggs was 0.6 millimeter, most of them being 

 equally developed. 



Total weight, in grams, of eggs from 110-centimeter black drum 996 



Total weight, in mUligrams, of 60 uuseleoted eggs 10 



Total calculated number of eggs in 1 gram 6,000 



Total calculated number of eggs in 996 grams 5, 976, 000 



Figure 23 presents the relation of weight to length in 77 black drum. A fish 

 about 30 centimeters long (11.8 inches) usually is slightly over 1 year of age and 

 weighs about 1 pound. Weight increases rapidly after 70 centimeters in length 

 (27.5 inches) has been reached. A drum measuring 90 centimeters (35.4 inches) 

 weighs close to 22 pounds, while a fish measuring 105 centimeters (41 inches) weighs 

 371^ pounds. 



SEASONAL DISTRIBUTION AND MOVEMENTS 



The young drum, usually in a larval or post-larval condition when brought in 

 through the passes from the Gulf spawning areas, make their way soon after enter- 

 ing to a few extremely shallow and muddy bodies of water typified, along the central 

 section of the Texas coast, by Laguna Madre and Oso and Nueces Bays. 



