PHYSICAL OCEANOGRAPHIC, BIOLOGICAL, AND CHEMICAL DATA 



SOUTH ATLANTIC COAST OF THE UNITED STATES 



M/V THEODORE N.GILL CRUISE 8 



This is the eighth in a series of 

 reports presenting basic data from cruises 

 of the Theodore N. Gill in waters off the 

 South Atl£intic coast of the United States. 



Background of the investigations; ob- 

 jectives; procedures on station; and chemi- 

 cal, biological, and oceanographic methods 

 and procedures were presented in the report 

 for Cruise 1 (Anderson, Gehringer, and 

 Cohen, 1956). Biological methods and proce- 

 dures were the same as those modified on 

 Cruise 3 (Anderson and Gehringer, 1957). 

 The basic station plan is shown in figure 1. 



NARRATIVE ACCOUNT OF CRUISE 8 



The Gill departed from Brimswick, 

 Georgia on August 27, 1954 to begin the 

 southern leg of the cruise. The passage of 

 three hurricanes delayed operations during 

 the early stages of the cruise and caused 

 cancellation of special stations 5 through 8 

 and the standard station, all of which were 

 usually worked at the start of a cruise. On 

 August 29, in the vicinity of Grand Bahama 

 Bank, the vessel experienced a damaged rud- 

 der and was towed by the U. S. Coast Guard 

 to Miami, Florida for repairs. These were 

 completed on September 3, and the vessel 

 proceeded to Nassau, B.W.I., arriving on 

 September 4. Equipment was loaded and in- 

 stalled in Nassau for special ambient work 

 by Columbia University personnel, but strong 

 winds cuid continued heavy rain squjills were 

 experienced during the time allotted for the 

 work, and it was cancelled to avoid disrup- 

 tion of the remainder of the cruise schedule. 

 The Gill sailed on September 10 from Nassau 

 for regular station 1, arriving at and 

 occupying that station on September 11. (k)od 

 weather prevailed during the remainder of 

 the southern leg of the cruise, and the ves- 

 sel occupied regular stations 1 through 34, 

 and special station 9, arriving back in 

 Brunswick, (Georgia for supplies on Septem- 

 ber 15. 



On September 20 the vessel departed 

 Brunswick to begin the northern leg of the 

 cruise. Adverse weather chjiracterized the 

 early stages of this leg suid this, together 

 with Loran trouble, forced the vessel into 

 Charleston, South Carolina on September 22, 

 The weather improved on September 25, and 

 operations were resumed. Regular stations 

 40, 41, 42, and 76 and special Stations 1 

 through 4 were not occupied because of 

 adverse weather conditions. The vessel re- 

 turned to Brunswick on October 1. 



Seventy-seven hydrographic stations 

 were occupied (76 regular and 1 special) 

 with Nansen casts and bathythermograph 

 lowerings on each station. Determinations 

 for dissolved oxygen were run aboard vessel 

 for all stations and all levels except for 

 regular stations 32, 33, and 34. Water 

 samples were obtained from all stations and 

 levels for shore analysis of salinity, 

 total phosphorus, inorganic phosphate, car- 

 bohydrates, proteins, and nitrate-nitrite. 

 Bottom sajnples were taken with a modified 

 orange-peel dredge on those stations where 

 several samples had not been collected on 

 previous cruises. Attempts were made to 

 secure bottom sediments with a modified 

 Phleger corer on a number of inshore sta- 

 tions, but the bottom over most of this 

 area was too hard for effective penetration 

 by this corer. Secchi disk readings were 

 taken during daylight hours when conditions 

 permitted. Oblique plankton tows (surface 

 tows in shallow water) were mjide with the 

 Gulf III all-metal plankton sampler on all 

 stations occupied. Fifty runs between sta- 

 tions were obtained with the Gulf lA high- 

 speed plankton sampler, and 28 runs were 

 obtained with the continuous plankton sajn- 

 pler. Dip-net fishing was carried out both 

 at night (under a light) and during the day 

 while on stat ion--results were fair on the 

 southern leg jind poor on the northern leg. 

 Trolling with feather and bone jigs between 

 stations yielded fair results. 



