was spent. He stated, "The number of fennales 

 in son-ie stage of development increased 

 steadily through August 1962. After this time, 

 total catches were much reduced but most of 

 the larger females were in a developing stage 

 through November. From December through 

 April, only 15 females were taken offshore 

 and all but 1 of these were undeveloped and 

 less than 140 mm. in length. One female, in 

 March, was in the 150-159 mm. range and 

 was developing." 



Figure 1 1 gives the size distributions and 

 table 7 the ovary developnnent of shrimp taken 

 in a series of hauls made off northeast Flor- 

 ida by the Oregon between about lat. 28°00' 

 and 29°30' N., and from 15 m. (8 fathoms) to 

 37 m. (20 fathoms) during July, August, and 

 September in 1965 and 1966. In samples frona 

 15 to 18 m. (8-10 fathoms), 24.3 percent were 

 undeveloped, 72.0 percent were developing, 

 and 3.7 percent were yellow. All of the few 

 females taken between 18 and 37 m. (10-20 

 fathoms) were developing; none were shorter 

 than 128 mm. These samples were from 

 waters offshore to the shallow coastal fishing 

 grounds. 



103 H3 123 133 143 153 163 173 183 193 203 

 98 I 108 I 118 I 128 I 138 I 148 | 158 I 168 I 178 i 188 i 198 | 



*- 17 



UJ 



U 16 



06 15 



13 



12 

 11 

 10 



9 



8 - 



7 



6 - 



5 



4 



3 



2 



1 



1 108 I 118 I 128 I 138 I 148 | 158 I 168 I 17 8 | 188 | 198 | 

 I I I I I I I ' I ' I ' I I I ' I ' I ■ I 



,/\ 



JULY TO SEPTEMBER 1965-66 



BETWEEN 15 AND18 METERS 



(8 TO 10 fathoms) 



142 MALES =43.0% 



190 FEMALES = 57.0% 





\ 



/\. 



I I I I I I I I I I 



I ■ I I I ' I I I I I 



AUGUST-SEPTEMBER 1965-66 



BETWEEN 18 AND37 METERS 



(10 TO 20 fathoms) 



18 MALES =48.6% 



• 19FEMALES = 51.4% 



I I I I I I I I I I ' I ■ I ' 



98 ' 108 ' 118 ' 128 ' 138 ' 148 ' 158 ' 168 ' 178 

 103 113 123 133 143 153 163 173 183 



I I ■ I 



188 ' 198 ' 



193 203 



TOTAL LENGTH (MM.) 

 Figure 11. — Size distribution and sex ratios of brown 

 shrimp off northeast Florida, between 15 and 37 m. 

 (8-20 fathoms), July to September, 1965-66. 



In a sample of II brown shrimp from Oregon 

 station 5341, lat. 28°03' N. and long. 80O02.5' 

 W., taken in 60 to 62 m. (33-34 fathoms) on 

 March 13, 1965, 3 were males (148-158 mm. 

 long) and 8 were fennales. All of the females -- 

 one 168 mm. long, and 7 ranging from 183 to 

 203 mm. (about maximum size for the species) 

 appeared to be spent. 



Ovary development of shrimp on the shallow 

 outside fishing grounds of northeast Florida 

 is the same as that of shrimp taken in Georgia: 

 females in the population of young shrimp dur- 

 ing May and June have undeveloped ovaries; 

 developing and yellow- stage ovaries increase 

 in frequency in July to September and a few 

 ripe females appear in September; and shrimp 

 disappear from the shallow outside fishing 

 grounds from fall to spring. In South Carolina 

 I found females with developing ovaries during 

 August and September but none with yellow or 

 ripe ovaries. 



From the records available, brown shrimp 

 must spawn in Florida waters in fall and winter 

 and almost entirely in waters offshore from 

 the shallow coastal fishing grounds, as very 

 few ripe females are captured on the shallow 

 grounds. The concentration of very large 

 brown shrimp in 55 to 66 nn. (30-36 fathoms) 

 off Cape Kennedy may well be the main spawn- 

 ing stock. 



North Carolina 



I have no brown shrimp records ironx this 

 State, but Williams (1955) gave evidence of 

 seasonal appearance of brown shrimp in the 

 shallow coastal fishery similar to that in 

 South Carolina, Georgia, and northeast Flor- 

 ida. In discussing recruitment of postlarvae 

 onto the nursery grounds he said, "Recruit- 

 ment to the annual populations is judged to 

 extend from late February to early June with 

 a peak in the first half of May." 



Regarding brown shrimp in the North Caro- 

 lina fishery, Williams (1955) said, "Penaeus 

 aztecus enters the commercial fishery in June 

 and recrmtment continues until September .... 

 The commercial shrimp season in North 

 Carolina has been opened during the first half 

 of May in recent years. During the first month 

 of the season, nearly all of the catch is com- 

 posed of P. duorarum , but in June P. aztecus 

 young adults rather suddenly appear in catches 

 made in the estuaries. Prior to this appear- 

 ance, the young have been on the nursery 

 grounds in the estuaries for two months or 

 more and their extremely rapid growth ac- 

 companied by nnigration toward deeper water 

 brings great numbers of the shrimp into fish- 

 able waters rather suddenly. The rapidly 

 maturing young swell the number of individ- 

 uals in the catches throughout the summer, 

 especially in Pamlico Sound. Broad (1951a) 

 wrote that this fishery reaches a peak in July 

 and August. The adult population also shows 



